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  • Java SWT - placing image buttons on the image background

    - by foma
    I am trying to put buttons with images(gif) on the background which has already been set as an image (shell.setBackgroundImage(image)) and I can't figure out how to remove transparent border around buttons with images. I would be grateful if somebody could give me some tip about this issue. Here is my code: import org.eclipse.swt.widgets.*; import org.eclipse.swt.layout.*; import org.eclipse.swt.*; import org.eclipse.swt.graphics.*; public class Main_page { public static void main(String[] args) { Display display = new Display(); Shell shell = new Shell(display); Image image = new Image(display, "bg.gif"); shell.setBackgroundImage(image); shell.setBackgroundMode(SWT.INHERIT_DEFAULT); shell.setFullScreen(true); Button button = new Button(shell, SWT.PUSH); button.setImage(new Image(display, "button.gif")); RowLayout Layout = new RowLayout(); shell.setLayout(Layout); shell.open(); while (!shell.isDisposed()) { if (!display.readAndDispatch()) display.sleep(); } display.dispose(); } } Sorceror, thanks for your answer I will definitely look into this article. Maybe I will find my way. So far I have improved my code a little bit. Firstly, I managed to get rid of the gray background noise. Secondly, I finally succeeded in creating the button as I had seen it in the first place. Yet, another obstacle has arisen. When I removed image(button) transparent border it turned out that the button change its mode(from push button to check box). The problem is that I came so close to the thing I was looking for and now I am a little puzzled. If you have some time please give a glance at my code. Here is the code, if you launch it you will see what the problem is(hope you didn't have problems downloading images): import org.eclipse.swt.widgets.*; import org.eclipse.swt.layout.*; import org.eclipse.swt.*; import org.eclipse.swt.graphics.*; public class Main_page { public static void main(String[] args) { Display display = new Display(); Shell shell = new Shell(display); Image image = new Image(display, "bg.gif"); // Launch on a screen 1280x1024 shell.setBackgroundImage(image); shell.setBackgroundMode(SWT.TRANSPARENT); shell.setFullScreen(true); GridLayout gridLayout = new GridLayout(); gridLayout.marginTop = 200; gridLayout.marginLeft = 20; shell.setLayout(gridLayout); // If you replace SWT.PUSH with SWT.COLOR_TITLE_INACTIVE_BACKGROUND // you will see what I am looking for, despite nasty check box Button button = new Button(shell, SWT.PUSH); button.setImage(new Image(display, "moneyfast.gif")); shell.open(); while (!shell.isDisposed()) { if (!display.readAndDispatch()) display.sleep(); } display.dispose(); }

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  • VHDL gate basics

    - by balina
    Hello. I'm learning VHDL and I've come to a halt. I'd like to create a simple gate out of smaller gates (a NAND gate here). Here's the code: library IEEE; use IEEE.STD_LOGIC_1164.all; entity ANDGATE2 is port( x,y : in STD_LOGIC; z : out STD_LOGIC ); end ANDGATE2; architecture ANDGATE2 of ANDGATE2 is begin z <= x AND y; end ANDGATE2; library IEEE; use IEEE.STD_LOGIC_1164.all; entity NOTGATE1 is port( x : in STD_LOGIC; z : out STD_LOGIC ); end NOTGATE1; architecture NOTGATE1 of NOTGATE1 is begin z <= NOT x; end NOTGATE1; library ieee; use ieee.std_logic_1164.all; entity NANDGATE2 is port( x : in STD_LOGIC; y : in STD_LOGIC; z : out STD_LOGIC ); end NANDGATE2; architecture NANDGATE2 of NANDGATE2 is signal c, d: std_logic; component NOTGATE1 port( n_in : in STD_LOGIC; n_out : out STD_LOGIC ); end component; component ANDGATE2 port( a_in1, a_in2 : in STD_LOGIC; a_out : out STD_LOGIC ); end component; begin N0: ANDGATE2 port map(x, y, c); N1: NOTGATE1 port map(c, d); z <= d; end NANDGATE2; Here's the code from some tutorial I've been using as a template; it compiles with no problems. library ieee; use ieee.std_logic_1164.all; -- definition of a full adder entity FULLADDER is port ( a, b, c: in std_logic; sum, carry: out std_logic ); end FULLADDER; architecture fulladder_behav of FULLADDER is begin sum <= (a xor b) xor c ; carry <= (a and b) or (c and (a xor b)); end fulladder_behav; -- 4-bit adder library ieee; use ieee.std_logic_1164.all; entity FOURBITADD is port ( a, b: in std_logic_vector(3 downto 0); Cin : in std_logic; sum: out std_logic_vector (3 downto 0); Cout, V: out std_logic ); end FOURBITADD; architecture fouradder_structure of FOURBITADD is signal c: std_logic_vector (4 downto 0); component FULLADDER port ( a, b, c: in std_logic; sum, carry: out std_logic ); end component; begin FA0: FULLADDER port map (a(0), b(0), Cin, sum(0), c(1)); FA1: FULLADDER port map (a(1), b(1), C(1), sum(1), c(2)); FA2: FULLADDER port map (a(2), b(2), C(2), sum(2), c(3)); FA3: FULLADDER port map (a(3), b(3), C(3), sum(3), c(4)); V <= c(3) xor c(4); Cout <= c(4); end fouradder_structure; My code compiles with no errors, but with two warnings: # Warning: ELAB1_0026: p2.vhd : (85, 0): There is no default binding for component "andgate2".(Port "a_in1" is not on the entity). # Warning: ELAB1_0026: p2.vhd : (87, 0): There is no default binding for component "notgate1".(Port "n_in" is not on the entity). What gives?

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  • jquery drag and drop script and problem in reading json array

    - by Mac Taylor
    i made a script , exactly like wordpress widgets page and u can drag and drop objects this is my jquery script : <script type="text/javascript" >$(function(){ $('.widget') .each(function(){ $(this).hover(function(){ $(this).find('h4').addClass('collapse'); }, function(){ $(this).find('h4').removeClass('collapse'); }) .find('h4').hover(function(){ $(this).find('.in-widget-title').css('visibility', 'visible'); }, function(){ $(this).find('.in-widget-title').css('visibility', 'hidden'); }) .click(function(){ $(this).siblings('.widget-inside').toggle(); //Save state on change of collapse state of panel updateWidgetData(); }) .end() .find('.in-widget-title').css('visibility', 'hidden'); }); $('.column').sortable({ connectWith: '.column', handle: 'h4', cursor: 'move', placeholder: 'placeholder', forcePlaceholderSize: true, opacity: 0.4, start: function(event, ui){ //Firefox, Safari/Chrome fire click event after drag is complete, fix for that if($.browser.mozilla || $.browser.safari) $(ui.item).find('.widget-inside').toggle(); }, stop: function(event, ui){ ui.item.css({'top':'0','left':'0'}); //Opera fix if(!$.browser.mozilla && !$.browser.safari) updateWidgetData(); } }) .disableSelection(); }); function updateWidgetData(){ var items=[]; $('.column').each(function(){ var columnId=$(this).attr('id'); $('.widget', this).each(function(i){ var collapsed=0; if($(this).find('.widget-inside').css('display')=="none") collapsed=1; //Create Item object for current panel var item={ id: $(this).attr('id'), collapsed: collapsed, order : i, column: columnId }; //Push item object into items array items.push(item); }); }); //Assign items array to sortorder JSON variable var sortorder={ items: items }; //Pass sortorder variable to server using ajax to save state $.post("blocks.php"+"&order="+$.toJSON(sortorder), function(data){ $('#console').html(data).fadeIn("slow"); }); } </script> main part is saving object orders in table and this is my php part : function stripslashes_deep($value) { $value = is_array($value) ? array_map('stripslashes_deep', $value) : stripslashes($value); return $value; } $order = $_GET['order']; $order = sql_quote($order); if(empty($order)){ echo "Invalid data"; exit; } global $db,$prefix; if (get_magic_quotes_gpc()) { $_POST = array_map('stripslashes_deep', $_POST); $_GET = array_map('stripslashes_deep', $_GET); $_COOKIE = array_map('stripslashes_deep', $_COOKIE); $_REQUEST = array_map('stripslashes_deep', $_REQUEST); } $data=json_decode($order); foreach($newdata->items as $item) { //Extract column number for panel $col_id=preg_replace('/[^\d\s]/', '', $item->column); //Extract id of the panel $widget_id=preg_replace('/[^\d\s]/', '', $item->id); $sql="UPDATE blocks_tbl SET bposition='$col_id', weight='".$item->order."' WHERE id='".$widget_id."'"; mysql_query($sql) or die('Error updating widget DB'); } print_r($order); now forexample the output is this : items\":[{\"id\":\"item26\",\"collapsed\":1,\"order\":0,\"column\":\"c\"},{\"id\":\"item0\",\"collapsed\":1,\"order\":0,\"column\":\"i\"},{\"id\":\"item0\",\"collapsed\":1,\"order\":1,\"column\":\"i\"},{\"id\":\"item1\",\"collapsed\":1,\"order\":2,\"column\":\"i\"},{\"id\":\"item3\",\"collapsed\":1,\"order\":3,\"column\":\"i\"},{\"id\":\"item16\",\"collapsed\":1,\"order\":4,\"column\":\"i\"},{\"id\":\"item0\",\"collapsed\":1,\"order\":5,\"column\":\"i\"},{\"id\":\"item6\",\"collapsed\":1,\"order\":6,\"column\":\"i\"},{\"id\":\"item17\",\"collapsed\":1,\"order\":7,\"column\":\"i\"},{\"id\":\"item19\",\"collapsed\":1,\"order\":8,\"column\":\"i\"},{\"id\":\"item10\",\"collapsed\":1,\"order\":9,\"column\":\"i\"},{\"id\":\"item11\",\"collapsed\":1,\"order\":10,\"column\":\"i\"},{\"id\":\"item0\",\"collapsed\":1,\"order\":0,\"column\":\"l\"},{\"id\":\"item5\",\"collapsed\":1,\"order\":1,\"column\":\"l\"},{\"id\":\"item8\",\"collapsed\":1,\"order\":2,\"column\":\"l\"},{\"id\":\"item13\",\"collapsed\":1,\"order\":3,\"column\":\"l\"},{\"id\":\"item21\",\"collapsed\":1,\"order\":4,\"column\":\"l\"},{\"id\":\"item28\",\"collapsed\":1,\"order\":5,\"column\":\"l\"},{\"id\":\"item7\",\"collapsed\":1,\"order\":0,\"column\":\"r\"},{\"id\":\"item20\",\"collapsed\":1,\"order\":1,\"column\":\"r\"},{\"id\":\"item15\",\"collapsed\":1,\"order\":2,\"column\":\"r\"},{\"id\":\"item18\",\"collapsed\":1,\"order\":3,\"column\":\"r\"},{\"id\":\"item14\",\"collapsed\":1,\"order\":4,\"column\":\"r\"}]} question is how can i find out column_id or order im a little bit confused

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  • java will this threading setup work or what can i be doing wrong

    - by Erik
    Im a bit unsure and have to get advice. I have the: public class MyApp extends JFrame{ And from there i do; MyServer = new MyServer (this); MyServer.execute(); MyServer is a: public class MyServer extends SwingWorker<String, Object> { MyServer is doing listen_socket.accept() in the doInBackground() and on connection it create a new class Connection implements Runnable { I have the belove DbHelper that are a singleton. It holds an Sqlite connected. Im initiating it in the above MyApp and passing references all the way in to my runnable: class Connection implements Runnable { My question is what will happen if there are two simultaneous read or `write? My thought here was the all methods in the singleton are synchronized and would put all calls in the queue waiting to get a lock on the synchronized method. Will this work or what can i change? public final class DbHelper { private boolean initalized = false; private String HomePath = ""; private File DBFile; private static final String SYSTEM_TABLE = "systemtable"; Connection con = null; private Statement stmt; private static final ContentProviderHelper instance = new ContentProviderHelper (); public static ContentProviderHelper getInstance() { return instance; } private DbHelper () { if (!initalized) { initDB(); initalized = true; } } private void initDB() { DBFile = locateDBFile(); try { Class.forName("org.sqlite.JDBC"); // create a database connection con = DriverManager.getConnection("jdbc:sqlite:J:/workspace/workComputer/user_ptpp"); } catch (SQLException e) { e.printStackTrace(); } catch (ClassNotFoundException e) { e.printStackTrace(); } } private File locateDBFile() { File f = null; try{ HomePath = System.getProperty("user.dir"); System.out.println("HomePath: " + HomePath); f = new File(HomePath + "/user_ptpp"); if (f.canRead()) return f; else { boolean success = f.createNewFile(); if (success) { System.out.println("File did not exist and was created " + HomePath); // File did not exist and was created } else { System.out.println("File already exists " + HomePath); // File already exists } } } catch (IOException e) { System.out.println("Maybe try a new directory. " + HomePath); //Maybe try a new directory. } return f; } public String getHomePath() { return HomePath; } private synchronized String getDate(){ SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); Date date = new Date(); return dateFormat.format(date); } public synchronized String getSelectedSystemTableColumn( String column) { String query = "select "+ column + " from " + SYSTEM_TABLE ; try { stmt = con.createStatement(ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_READ_ONLY); ResultSet rs = stmt.executeQuery(query); while (rs.next()) { String value = rs.getString(column); if(value == null || value == "") return ""; else return value; } } catch (SQLException e ) { e.printStackTrace(); return ""; } finally { } return ""; } }

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  • Clearcase - selective merge.

    - by Keshav
    Hi, I have a peculiar Clearcase doubt. I cannot fully describe why I'm doing such a confusing architecture, but I need to do it (thanks to the mistake done by someone long back). Ok, here's a bit of detail: B1 is a contaminated branch where both my group's changes and another group's changes got mixed together so badly that there is no way of finding which code is whose). So the solution proposed is to create a new branch called B2 (at the same level as B1) and put all the unmodified code of the other group on it (The way to do that would be to merge B1 with B2 and then go about removing all changes from it till it becomes original). Then create a CR branch on B1 and keep only my group's newly added files or modified files on that branch. Finally create an integration branch out of B2 and merge the changes from CR branch of B1 to integration branch of B2. So here is what I did: (The use case is where I have dir D where file a, b and c are there. My group ended up modifying file a while b and c are not modified at all). There is a branch B1 on which there are files a, b and c. There is another branch B2. A merge is done from B1 to B2. Now B2 also has a, b and c. At this point both branch B1 and B2 are same. Now I delete file a from branch B2 (rmname). Now B2 has b and c only. I put a label to this branch called Label1. This makes the code with label Label1 as the unmodified code from other group. Now I create a sub branch called CR1 from B1 and delete all the files that are there in B2 branch (i.e b and c) such that it contains only the modified code from original code on it. In my case it is file a. At this point branch B2 with label Label1 has files b and c (those are unmodified code) and branch CR1 coming off B1 has only a (that is modified by us). Now I create another branch called integration branch that comes off B2 Label1. And then I do a merge of CR branch on to that expecting that it will have all three files a, b and c for me. All I'd need to do is to do a version tree view and see who modified what. But the problem I face is that since I had done a rmname of file a on branch B2 earlier to putting Label. The merge does not really take the file a from CR branch. How to I get around that problem. I want to selectively merge. Is it possible? sorry if it is a bad design. I'm not really conversant with Clear case and have limited options and time to clear some one else's mess.

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  • Fastest way to pad a number in Java to a certain number of digits

    - by Martin
    Am trying to create a well-optimised bit of code to create number of X-digits in length (where X is read from a runtime properties file), based on a DB-generated sequence number (Y), which is then used a folder-name when saving a file. I've come up with three ideas so far, the fastest of which is the last one, but I'd appreciate any advice people may have on this... 1) Instantiate a StringBuilder with initial capacity X. Append Y. While length < X, insert a zero at pos zero. 2) Instantiate a StringBuilder with initial capacity X. While length < X, append a zero. Create a DecimalFormat based on StringBuilder value, and then format the number when it's needed. 3) Create a new int of Math.pow( 10, X ) and add Y. Use String.valueOf() on the new number and then substring(1) it. The second one can obviously be split into outside-loop and inside-loop sections. So, any tips? Using a for-loop of 10,000 iterations, I'm getting similar timings from the first two, and the third method is approximately ten-times faster. Does this seem correct? Full test-method code below... // Setup test variables int numDigits = 9; int testNumber = 724; int numIterations = 10000; String folderHolder = null; DecimalFormat outputFormat = new DecimalFormat( "#,##0" ); // StringBuilder test long before = System.nanoTime(); for ( int i = 0; i < numIterations; i++ ) { StringBuilder sb = new StringBuilder( numDigits ); sb.append( testNumber ); while ( sb.length() < numDigits ) { sb.insert( 0, 0 ); } folderHolder = sb.toString(); } long after = System.nanoTime(); System.out.println( "01: " + outputFormat.format( after - before ) + " nanoseconds" ); System.out.println( "Sanity check: Folder = \"" + folderHolder + "\"" ); // DecimalFormat test before = System.nanoTime(); StringBuilder sb = new StringBuilder( numDigits ); while ( sb.length() < numDigits ) { sb.append( 0 ); } DecimalFormat formatter = new DecimalFormat( sb.toString() ); for ( int i = 0; i < numIterations; i++ ) { folderHolder = formatter.format( testNumber ); } after = System.nanoTime(); System.out.println( "02: " + outputFormat.format( after - before ) + " nanoseconds" ); System.out.println( "Sanity check: Folder = \"" + folderHolder + "\"" ); // Substring test before = System.nanoTime(); int baseNum = (int)Math.pow( 10, numDigits ); for ( int i = 0; i < numIterations; i++ ) { int newNum = baseNum + testNumber; folderHolder = String.valueOf( newNum ).substring( 1 ); } after = System.nanoTime(); System.out.println( "03: " + outputFormat.format( after - before ) + " nanoseconds" ); System.out.println( "Sanity check: Folder = \"" + folderHolder + "\"" );

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  • Having trouble storing a CRTP based class in a vector

    - by user366834
    Hi, Im not sure if this can be done, im just delving into templates so perhaps my understanding is a bit wrong. I have a Platoon of soldiers, the platoon inherits from a formation to pick up the formations properties, but because i could have as many formations as i can think of I chose to use the CRTP to create the formations, hoping that i could make a vector or array of Platoon to store the platoons in. but, of course, when i make a Platoon, it wont store it in the vector, "types are unrelated" Is there any way around this ? i read about "Veneers" which are similar and that they work with arrays but i cant get it to work, perhaps im missing something. here's some code: (sorry about the formatting, the code is here in my post but its not showing up for some reason ) template < class TBase > class IFormation { public : ~IFormation(){} bool IsFull() { return m_uiMaxMembers == m_uiCurrentMemCount; } protected: unsigned int m_uiCurrentMemCount; unsigned int m_uiMaxMembers; IFormation( unsigned int _uiMaxMembers ): m_uiMaxMembers( _uiMaxMembers ), m_uiCurrentMemCount( 0 ){} // only allow use as a base class. void SetupFormation( std::vector<MySoldier*>& _soldierList ){}; // must be implemented in derived class }; ///////////////////////////////////////////////////////////////////////////////// // PHALANX FORMATION class Phalanx : public IFormation<Phalanx> { public: Phalanx( ): IFormation( 12 ), m_fDistance( 4.0f ) {} ~Phalanx(){} protected: float m_fDistance; // the distance between soldiers void SetupFormation( std::vector<MySoldier*>& _soldierList ); }; /////////////////////////////////////////////////////////////////////////////////// // COLUMN FORMATINO class Column : public IFormation< Column > { public : Column( int _numOfMembers ): IFormation( _numOfMembers ) {} ~Column(); protected: void SetupFormation( std::vector<MySoldier*>& _soldierList ); }; I then use these formations in the platoon class to derive, so that platoon gets the relevant SetupFormation() function: template < class Formation > class Platoon : public Formation { public: **** platoon code here }; everything works great and as expected up until this point. now, as my general can have multiple platoons, I need to store the platoons. typedef Platoon< IFormation<> > TPlatoon; // FAIL typedef std::vector<TPlatoon*> TPlatoons; TPlatoon m_pPlatoons m_pPlatoons.push_back( new Platoon<Phalanx> ); // FAIL, types unrelated. typedef Platoon< IFormation< TPlatoon; fails because i need to specify a template parameter, yet specifying this will only allow me to store platoons created with the same template parameter. so i then created FormationBase class FormationBase { public: virtual bool IsFull() = 0; virtual void SetupFormation( std::vector<MySoldier*>& _soldierList ) = 0; }; and made IFormation publicly inherit from that, and then changed the typedef to typedef Platoon< IFormation< FormationBase > > TPlatoon; but still no love. now in my searches i have not found info that says this is possible - or not possible.

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  • (SQL) Selecting from a database based on multiple pairs of pairs

    - by Owen Allen
    The problem i've encountered is attempting to select rows from a database where 2 columns in that row align to specific pairs of data. IE selecting rows from data where id = 1 AND type = 'news'. Obviously, if it was 1 simple pair it would be easy, but the issue is we are selecting rows based on 100s of pair of data. I feel as if there must be some way to do this query without looping through the pairs and querying each individually. I'm hoping some SQL stackers can provide guidance. Here's a full code break down: Lets imagine that I have the following dataset where history_id is the primary key. I simplified the structure a bit regarding the dates for ease of reading. table: history history_id id type user_id date 1 1 news 1 5/1 2 1 news 1 5/1 3 1 photo 1 5/2 4 3 news 1 5/3 5 4 news 1 5/3 6 1 news 1 5/4 7 2 photo 1 5/4 8 2 photo 1 5/5 If the user wants to select rows from the database based on a date range we would take a subset of that data. SELECT history_id, id, type, user_id, date FROM history WHERE date BETWEEN '5/3' AND '5/5' Which returns the following dataset history_id id type user_id date 4 3 news 1 5/3 5 4 news 1 5/3 6 1 news 1 5/4 7 2 photo 1 5/4 8 2 photo 1 5/5 Now, using that subset of data I need to determine how many of those entries represent the first entry in the database for each type,id pairing. IE is row 4 the first time in the database that id: 3, type: news appears. So I use a with() min() query. In real code the two lists are programmatically generated from the result sets of our previous query, here I spelled them out for ease of reading. WITH previous AS ( SELECT history_id, id, type FROM history WHERE id IN (1,2,3,4) AND type IN ('news','photo') ) SELECT min(history_id) as history_id, id, type FROM previous GROUP BY id, type Which returns the following data set. history_id id type user_id date 1 1 news 1 5/1 2 1 news 1 5/1 3 1 photo 1 5/2 4 3 news 1 5/3 5 4 news 1 5/3 6 1 news 1 5/4 7 2 photo 1 5/4 8 2 photo 1 5/5 You'll notice it's the entire original dataset, because we are matching id and type individually in lists, rather than as a collective pairs. The result I desire is, but I can't figure out the SQL to get this result. history_id id type user_id date 1 1 news 1 5/1 4 3 news 1 5/3 5 4 news 1 5/3 7 2 photo 1 5/4 Obviously, I could go the route of looping through each pair and querying the database to determine it's first result, but that seems an inefficient solution. I figured one of the SQL gurus on this site might be able to spread some wisdom. In case I'm approaching this situation incorrectly, the gist of the whole routine is that the database stores all creations and edits in the same table. I need to track each users behavior and determine how many entries in the history table are edits or creations over a specific date range. Therefore I select all type:id pairs from the date range based on a user_id, and then for each pairing I determine if the user is responsible for the first that occurs in the database. If first, then creation else edit. Any assistance would be awesome.

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  • Accessing Layout Items from inside Widget AppWidgetProvider

    - by cam4mav
    I am starting to go insane trying to figure this out. It seems like it should be very easy, I'm starting to wonder if it's possible. What I am trying to do is create a home screen widget, that only contains an ImageButton. When it is pressed, the idea is to change some setting (like the wi-fi toggle) and then change the Buttons image. I have the ImageButton declared like this in my main.xml <ImageButton android:id="@+id/buttonOne" android:src="@drawable/button_normal_ringer" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center" /> my AppWidgetProvider class, named ButtonWidget * note that the RemoteViews class is a locally stored variable. this allowed me to get access to the RViews layout elements... or so I thought. @Override public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) { remoteViews = new RemoteViews(context.getPackageName(), R.layout.main); Intent active = new Intent(context, ButtonWidget.class); active.setAction(VIBRATE_UPDATE); active.putExtra("msg","TESTING"); PendingIntent actionPendingIntent = PendingIntent.getBroadcast(context, 0, active, 0); remoteViews.setOnClickPendingIntent(R.id.buttonOne, actionPendingIntent); appWidgetManager.updateAppWidget(appWidgetIds, remoteViews); } @Override public void onReceive(Context context, Intent intent) { // v1.5 fix that doesn't call onDelete Action final String action = intent.getAction(); Log.d("onReceive",action); if (AppWidgetManager.ACTION_APPWIDGET_DELETED.equals(action)) { final int appWidgetId = intent.getExtras().getInt( AppWidgetManager.EXTRA_APPWIDGET_ID, AppWidgetManager.INVALID_APPWIDGET_ID); if (appWidgetId != AppWidgetManager.INVALID_APPWIDGET_ID) { this.onDeleted(context, new int[] { appWidgetId }); } } else { // check, if our Action was called if (intent.getAction().equals(VIBRATE_UPDATE)) { String msg = "null"; try { msg = intent.getStringExtra("msg"); } catch (NullPointerException e) { Log.e("Error", "msg = null"); } Log.d("onReceive",msg); if(remoteViews != null){ Log.d("onReceive",""+remoteViews.getLayoutId()); remoteViews.setImageViewResource(R.id.buttonOne, R.drawable.button_pressed_ringer); Log.d("onReceive", "tried to switch"); } else{ Log.d("F!", "--naughty language used here!!!--"); } } super.onReceive(context, intent); } } so, I've been testing this and the onReceive method works great, I'm able to send notifications and all sorts of stuff (removed from code for ease of reading) the one thing I can't do is change any properties of the view elements. To try and fix this, I made RemoteViews a local and static private variable. Using log's I was able to see that When multiple instances of the app are on screen, they all refer to the one instance of RemoteViews. perfect for what I'm trying to do The trouble is in trying to change the image of the ImageButton. I can do this from within the onUpdate method using this. remoteViews.setImageViewResource(R.id.buttonOne, R.drawable.button_pressed_ringer); that doesn't do me any good though once the widget is created. For some reason, even though its inside the same class, being inside the onReceive method makes that line not work. That line used to throw a Null pointer as a matter of fact, until I changed the variable to static. now it passes the null test, refers to the same layoutId as it did at the start, reads the line, but it does nothing. Its like the code isn't even there, just keeps chugging along. SO...... Is there any way to modify layout elements from within a widget after the widget has been created!? I want to do this based on the environment, not with a configuration activity launch. I've been looking at various questions and this seems to be an issue that really hasn't been solved, such as link text and link text oh and for anyone who finds this and wants a good starting tutorial for widgets, this is easy to follow (though a bit old, it gets you comfortable with widgets) .pdf link text hopefully someone can help here. I kinda have the feeling that this is illegal and there is a different way to go about this. I would LOVE to be told another approach!!!! Thanks

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  • AJAX Generated Select Won't Redirect

    - by James
    So, basically I have this select / drop down menu that I use AJAX to retrieve and create, though when an option is selected (so onChange) I want it to redirect! Though, this still isn't working, I don't get any errors thrown when trying, and tried to do alert() debug methods yet the alerts don't get called. jquery $("#schoolMenu").change(function() { option = $("#schoolMenu option:selected").text(); alert(option); if(option != "- Please Select -") { window.location = "http://www.itmustbecollege.com/pics/pics-from-"+$("#schoolMenu option:selected").val(); } }); This is what is used to call the AJAX // // Populate Schools // $("#state").change(function() { option = $("#state option:selected").text(); if($(this).attr("class") == "menu") { if(option != "- Please Select -") { $.ajax({ type: "GET", url: "/includes/functions.php", data: "f=school&p="+option+"&m=yes", success: function(msg) { $("#fSchool").html("<p style=\"margin-left: 20px;\">Select School:</p>"+ msg); $("#fSchool").show(); $("#school").focus(); } }); } else { $("#fSchool").html(""); $("#fSchool").hide(); } } else { if(option != "- Please Select -") { $.ajax({ type: "GET", url: "/includes/functions.php", data: "f=school&p="+option, success: function(msg) { $("#fSchool").html(msg); $("#fSchool").show(); $("#school").focus(); } }); } else { $("#fSchool").html(""); $("#fSchool").hide(); } } }); It loads perfectly, if you look at http://www.itmustbecollege.com/quotes/ on that bar where you can do "sort by" of Popular | Newest | Category | School if you hover over school a dropdown comes up, select any country and another one appears, though when that is changed nothing happens. here is the PHP for that second drop down // Get College List function getCollege($state, $m = "no", $l = "no") { // Displays Schools if($m == "yes") { $options = '<select id="schoolMenu" name="school"><option value="select" selected="selected">- Please Select -</option>'; } else if($l == "yes" || $l == "yes2") { $options = ''; } else { $options = '<select name="school"><option value="select" selected="selected">- Please Select -</option>'; } $listArray = split("\|\\\\", $list); for($i=0; $i < count($listArray); $i++) { if($m == "yes") { $options .= '<option value="'. trim(titleReplace($listArray[$i])) .'">'. trim($listArray[$i]) .'</option>'; } else if($l == "yes") { $options .= '<li><a href="/quotes/quotes-from-'. titleReplace($listArray[$i]) .'" title="'. trim($listArray[$i]) .' Quotes">'. trim($listArray[$i]) .'</a></li>'; } else if($l == "yes2") { $options .= '<li><a href="/pics/pics-from-'. titleReplace($listArray[$i]) .'" title="'. trim($listArray[$i]) .' Pictures">'. trim($listArray[$i]) .'</a></li>'; } else { $options .= '<option value="'. trim($listArray[$i]) .'">'. trim($listArray[$i]) .'</option>'; } } echo $options .='</select>'; return false; } any help would be great! EDIT: Also, the way I have those drop downs coming for the menus is a bit weird and when you hover over any other "sort by" link they disappear, this is a problem with the "sort by school" because the first select box shows the list up, and if you go and select a school then somehow float over another link it disappears, any help on how to delay that or fix that minor problem?

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  • error in assigning a const character to an unsigned char array in C++

    - by mekasperasky
    #include <iostream> #include <fstream> #include <cstring> using namespace std; typedef unsigned long int WORD; /* Should be 32-bit = 4 bytes */ #define w 32 /* word size in bits */ #define r 12 /* number of rounds */ #define b 16 /* number of bytes in key */ #define c 4 /* number words in key */ /* c = max(1,ceil(8*b/w)) */ #define t 26 /* size of table S = 2*(r+1) words */ WORD S [t],L[c]; /* expanded key table */ WORD P = 0xb7e15163, Q = 0x9e3779b9; /* magic constants */ /* Rotation operators. x must be unsigned, to get logical right shift*/ #define ROTL(x,y) (((x)<<(y&(w-1))) | ((x)>>(w-(y&(w-1))))) #define ROTR(x,y) (((x)>>(y&(w-1))) | ((x)<<(w-(y&(w-1))))) void RC5_DECRYPT(WORD *ct, WORD *pt) /* 2 WORD input ct/output pt */ { WORD i, B=ct[1], A=ct[0]; for (i=r; i>0; i--) { B = ROTR(B-S [2*i+1],A)^A; A = ROTR(A-S [2*i],B)^B; } pt [1] = B-S [1] ;pt [0] = A-S [0]; } void RC5_SETUP(unsigned char *K) /* secret input key K 0...b-1] */ { WORD i, j, k, u=w/8, A, B, L [c]; /* Initialize L, then S, then mix key into S */ for (i=b-1,L[c-1]=0; i!=-1; i--) L[i/u] = (L[i/u]<<8)+K[ i]; for (S [0]=P,i=1; i<t; i++) S [i] = S [i-1]+Q; for (A=B=i=j=k=0; k<3*t; k++,i=(i+1)%t,j=(j+1)%c) /* 3*t > 3*c */ { A = S[i] = ROTL(S [i]+(A+B),3); B = L[j] = ROTL(L[j]+(A+B),(A+B)); } } void printword(WORD A) { WORD k; for (k=0 ;k<w; k+=8) printf("%02.2lX",(A>>k)&0xFF); } int main() { WORD i, j, k, pt [2], pt2 [2], ct [2] = {0,0}; unsigned char key[b]; ofstream out("cpt.txt"); ifstream in("key.txt"); if(!in) { cout << "Cannot open file.\n"; return 1; } if(!out) { cout << "Cannot open file.\n"; return 1; } key="111111000001111"; RC5_SETUP(key); ct[0]=2185970173; ct[1]=3384368406; for (i=1;i<2;i++) { RC5_DECRYPT(ct,pt2); printf("\n plaintext "); printword(pt [0]); printword(pt[1]); } return 0; } When I compile this code, I get two warnings and also an error saying that I can't assign a char value to my character array. Why is that?

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  • Can't figure out this file behavior in IOS 4.2

    - by Don Jones
    Odd behavior with file behavior. Here's the thing: I'm using the phone camera to snap a picture, and internally generating a thumbnail. I'm saving those as temp files in the Documents directory. Here's the complete code: - (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info { UIImage *photo = [info objectForKey:@"UIImagePickerControllerOriginalImage"]; photo = [self scaleAndRotateImage:photo]; // save photo NSString *docsDir = [NSHomeDirectory() stringByAppendingPathComponent:@"Documents"]; NSLog(@"Writing to %@",docsDir); // save photo file NSLog(@"Saving photo as %@",[NSString stringWithFormat:@"%@/temp_photo.png",docsDir]); [UIImagePNGRepresentation(photo) writeToFile:[NSString stringWithFormat:@"%@/temp_photo.png",docsDir] atomically:YES]; // make and save thumbnail NSLog(@"Saving thumbnail as %@",[NSString stringWithFormat:@"%@/temp_thumb.png",docsDir]); UIImage *thumb = [self makeThumbnail:photo]; [UIImagePNGRepresentation(thumb) writeToFile:[NSString stringWithFormat:@"%@/temp_thumb.png",docsDir] atomically:YES]; NSFileManager *manager = [NSFileManager defaultManager]; NSError *error; NSArray *files = [manager contentsOfDirectoryAtPath:docsDir error:&error]; NSLog(@"\n\nThere are %d files in the documents directory %@",(files.count),docsDir); for (int i = 0; i < files.count; i++) { NSString *filename = [files objectAtIndex:i]; NSLog(@"Seeing filename %@",filename); } // done //[photo release]; //[thumb release]; [self dismissModalViewControllerAnimated:NO]; [delegate textInputFinished]; } As you can see, I've put quite a bit of logging in here in an attempt to figure out my problem (which is coming up). The log output to this point is: Writing to /var/mobile/Applications/77D792DC-A224-4A47-8A4C-BB7C557626F3/Documents Saving photo as /var/mobile/Applications/77D792DC-A224-4A47-8A4C-BB7C557626F3/Documents/temp_photo.png Saving thumbnail as /var/mobile/Applications/77D792DC-A224-4A47-8A4C-BB7C557626F3/Documents/temp_thumb.png There are 3 files in the documents directory /var/mobile/Applications/77D792DC-A224-4A47-8A4C-BB7C557626F3/Documents Seeing filename temp_photo.png Seeing filename temp_text.txt Seeing filename temp_thumb.png This is absolutely as-expected. I clearly have three files on the device. Here's the very next code that operates - the code that received the textInputFinished message: - (void)textInputFinished { NSFileManager *fileManager = [NSFileManager defaultManager]; NSString *docsDir = [NSHomeDirectory() stringByAppendingPathComponent:@"Documents"]; NSError *error; // get next filename NSString *filename; int i = 0; do { i++; filename = [NSString stringWithFormat:@"%@/reminder_%d",docsDir,i]; NSLog(@"Trying filename %@",filename); } while ([fileManager fileExistsAtPath:[filename stringByAppendingString:@".txt"]]); NSLog(@"New base filename is %@",filename); NSArray *files = [fileManager contentsOfDirectoryAtPath:docsDir error:&error]; NSLog(@"There are %d files in the directory %@",(files.count),docsDir); This is testing to get a new, non-temp, not-in-use filename. It does that - but then it says there aren't any files in the documents folder! Here's the logged output: Trying filename /var/mobile/Applications/77D792DC-A224-4A47-8A4C-BB7C557626F3/Documents/reminder_1 New base filename is /var/mobile/Applications/77D792DC-A224-4A47-8A4C-BB7C557626F3/Documents/reminder_1 There are 0 files in the directory /var/mobile/Applications/77D792DC-A224-4A47-8A4C-BB7C557626F3/Documents What the heck? Where did the three files go?

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  • Logcat error: "addView(View, LayoutParams) is not supported in AdapterView" in a ListView

    - by HacKreatorz
    I'm doing an aplication for Android and something I need is that it shows a list of all files and directories in the SD Card and it has to be able to move through the different directories. I found a good tutorial in anddev: http://bit.ly/h4GyFC I modified a few things so the aplication moves in the SD Card and not in Android root Directories but the rest is mostly the same. This is my xml file for the activity: <?xml version="1.0" encoding="utf-8"?> <ListView xmlns:android="http://schemas.android.com/apk/res/android" android:id="@id/android:list" android:layout_width="fill_parent" android:layout_height="fill_parent"> <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" /> </ListView> And this is the code for the Activity: import hackreatorz.cifrador.R; import java.io.File; import java.util.ArrayList; import android.app.ListActivity; import android.content.res.Configuration; import android.os.Bundle; import android.view.View; import android.widget.ArrayAdapter; import android.widget.ListView; import android.widget.Toast; public class ArchivosSD extends ListActivity { private ArrayList<String> directoryEntries = new ArrayList<String>(); private File currentDirectory = new File("/sdcard/"); @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); browseToSD(); } @Override public void onConfigurationChanged(Configuration newConfig) { super.onConfigurationChanged(newConfig); } private void browseToSD() { browseTo(new File("/sdcard/")); } private void upOneLevel() { if(this.currentDirectory.getParent() != null) this.browseTo(this.currentDirectory.getParentFile()); } private void browseTo(final File directory) { if (directory.isDirectory()) { this.currentDirectory = directory; fill(directory.listFiles()); } else { Toast.makeText(ArchivosSD.this, this.directoryEntries.get(this.getSelectedItemPosition()), Toast.LENGTH_SHORT).show(); } } private void fill(File[] files) { this.directoryEntries.clear(); this.directoryEntries.add(getString(R.string.current_dir)); if(this.currentDirectory.getParent() != null) this.directoryEntries.add(getString(R.string.up_one_level)); int currentPathStringLength = (int) this.currentDirectory.getAbsoluteFile().length(); for (File file : files) { this.directoryEntries.add(file.getAbsolutePath().substring(currentPathStringLength)); } setListAdapter(new ArrayAdapter<String>(this, R.layout.archivos_sd, this.directoryEntries)); } @Override protected void onListItemClick(ListView l, View v, int position, long id) { int selectionRowID = (int) this.getSelectedItemPosition(); String selectedFileString = this.directoryEntries.get(selectionRowID); if (selectedFileString.equals(".")) { this.browseToSD(); } else if(selectedFileString.equals("..")) { this.upOneLevel(); } else { File clickedFile = null; clickedFile = new File(this.currentDirectory.getAbsolutePath() + this.directoryEntries.get(selectionRowID)); if(clickedFile != null) this.browseTo(clickedFile); } } } I don't get any errores in Eclipse, but I get a Force Close when running the aplication on my phone and when I look at Logcat I see the following: 01-01 23:30:29.858: ERROR/AndroidRuntime(14911): FATAL EXCEPTION: main *01-01 23:30:29.858: ERROR/AndroidRuntime(14911): java.lang.UnsupportedOperationException: addView(View, LayoutParams) is not supported in AdapterView* I don't have a clue what to do, I've looked up in Google and I didn't find anything and I did the same at stackoverflow. This is my first aplication in Java and for Android so I'm a real n00b and if the answer was there, I didn't understand it so I would really apreciate if you could explain what I should do to fix this error and why. Thanks for everything in advanced.

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  • Insert a transformed integer_sequence into a variadic template argument?

    - by coderforlife
    How do you insert a transformed integer_sequence (or similar since I am targeting C++11) into a variadic template argument? For example I have a class that represents a set of bit-wise flags (shown below). It is made using a nested-class because you cannot have two variadic template arguments for the same class. It would be used like typedef Flags<unsigned char, FLAG_A, FLAG_B, FLAG_C>::WithValues<0x01, 0x02, 0x04> MyFlags. Typically, they will be used with the values that are powers of two (although not always, in some cases certain combinations would be made, for example one could imagine a set of flags like Read=0x1, Write=0x2, and ReadWrite=0x3=0x1|0x2). I would like to provide a way to do typedef Flags<unsigned char, FLAG_A, FLAG_B, FLAG_C>::WithDefaultValues MyFlags. template<class _B, template <class,class,_B> class... _Fs> class Flags { public: template<_B... _Vs> class WithValues : public _Fs<_B, Flags<_B,_Fs...>::WithValues<_Vs...>, _Vs>... { // ... }; }; I have tried the following without success (placed inside the Flags class, outside the WithValues class): private: struct _F { // dummy class which can be given to a flag-name template template <_B _V> inline constexpr explicit _F(std::integral_constant<_B, _V>) { } }; // we count the flags, but only in a dummy way static constexpr unsigned _count = sizeof...(_Fs<_B, _F, 1>); static inline constexpr _B pow2(unsigned exp, _B base = 2, _B result = 1) { return exp < 1 ? result : pow2(exp/2, base*base, (exp % 2) ? result*base : result); } template <_B... _Is> struct indices { using next = indices<_Is..., sizeof...(_Is)>; using WithPow2Values = WithValues<pow2(_Is)...>; }; template <unsigned N> struct build_indices { using type = typename build_indices<N-1>::type::next; }; template <> struct build_indices<0> { using type = indices<>; }; //// Another attempt //template < _B... _Is> struct indices { // using WithPow2Values = WithValues<pow2(_Is)...>; //}; //template <unsigned N, _B... _Is> struct build_indices // : build_indices<N-1, N-1, _Is...> { }; //template < _B... _Is> struct build_indices<0, _Is...> // : indices<_Is...> { }; public: using WithDefaultValues = typename build_indices<_count>::type::WithPow2Values; Of course, I would be willing to have any other alternatives to the whole situation (supporting both flag names and values in the same template set, etc). I have included a "working" example at ideone: http://ideone.com/NYtUrg - by "working" I mean compiles fine without using default values but fails with default values (there is a #define to switch between them). Thanks!

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  • Flash Mouse.hide() cmd+tab(alt+tab) bring the mouse back

    - by DickieBoy
    Having a bit of trouble with Mouse.show() and losing focus of the swf This isn't my demo: but its showing the same bug http://www.foundation-flash.com/tutorials/as3customcursors/ What i do to recreate it is: mouse over the swf, hit cmd+tab to highlight another window, result is that the mouse is not brought back and is still invisible, (to get it back go to the window bar at the top of the screen and click something). I have an area in which movement is detected and an image Things I have tried package { import flash.display.Sprite; import flash.display.MovieClip; import com.greensock.*; import flash.events.*; import flash.utils.Timer; import flash.events.TimerEvent; import flash.utils.*; import flash.ui.Mouse; public class mousey_movey extends MovieClip { public var middle_of_the_flash; //pixels per second public var speeds = [0,1,3,5,10]; public var speed; public var percentage_the_mouse_is_across_the_screen; public var mouse_over_scrollable_area:Boolean; public var image_move_interval; public function mousey_movey() { middle_of_the_flash = stage.stageWidth/2; hot_area_for_movement.addEventListener(MouseEvent.MOUSE_OVER, mouseEnter); hot_area_for_movement.addEventListener(MouseEvent.MOUSE_OUT, mouseLeave); hot_area_for_movement.addEventListener(MouseEvent.MOUSE_MOVE, mouseMove); stage.addEventListener(Event.MOUSE_LEAVE, show_mouse); stage.addEventListener(MouseEvent.MOUSE_OUT, show_mouse); stage.addEventListener(Event.DEACTIVATE,show_mouse); hot_area_for_movement.alpha=0; hot_area_for_movement.x=0; hot_area_for_movement.y=34; } public function show_mouse(e) { trace(e.type) trace('show_mouse') Mouse.show(); } public function onActivate(e) { trace('activate'); Mouse.show(); } public function onDeactivate(e) { trace('deactivate'); } public function get_speed(percantage_from_middle):int { if(percantage_from_middle > 80) { return speeds[4] } else { if(percantage_from_middle > 60) { return speeds[3] } else { if(percantage_from_middle > 40) { return speeds[2] } else { if(percantage_from_middle > 20) { return speeds[1] } else { return 0; } } } } } public function mouseLeave(e:Event):void{ Mouse.show(); clearInterval(image_move_interval); } public function mouseEnter(e:Event):void{ Mouse.hide(); image_move_interval = setInterval(moveImage,1); } public function mouseMove(e:Event):void { percentage_the_mouse_is_across_the_screen = Math.round(((middle_of_the_flash-stage.mouseX)/middle_of_the_flash)*100); speed = get_speed(Math.abs(percentage_the_mouse_is_across_the_screen)); airplane_icon.x = stage.mouseX; airplane_icon.y = stage.mouseY; } public function stageMouseMove(e:Event):void{ Mouse.show(); } public function moveImage():void { if(percentage_the_mouse_is_across_the_screen > 0) { moving_image.x+=speed; airplane_icon.scaleX = -1; } else { moving_image.x-=speed; airplane_icon.scaleX = 1; } } } } Nothing too fancy, im just scrolling an image left of right at a speed which is generated by how far you are from the middle of the stage, and making an airplane moveclip follow the mouse. The events: stage.addEventListener(Event.MOUSE_LEAVE, show_mouse); stage.addEventListener(MouseEvent.MOUSE_OUT, show_mouse); stage.addEventListener(Event.DEACTIVATE,show_mouse); All fire and work correctly when in the browser, seem a little buggy when running a test through flash, was expecting this as ive experienced it before. The deactivate call even runs when testing and cmd+tabbing but shows no mouse. Any help on the matter is appreciated Thanks, Dickie

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  • C++ Optimize if/else condition

    - by Heye
    I have a single line of code, that consumes 25% - 30% of the runtime of my application. It is a less-than comparator for an std::set (the set is implemented with a Red-Black-Tree). It is called about 180 Million times within 52 seconds. struct Entry { const float _cost; const long _id; // some other vars Entry(float cost, float id) : _cost(cost), _id(id) { } }; template<class T> struct lt_entry: public binary_function <T, T, bool> { bool operator()(const T &l, const T &r) const { // Most readable shape if(l._cost != r._cost) { return r._cost < l._cost; } else { return l._id < r._id; } } }; The entries should be sorted by cost and if the cost is the same by their id. I have many insertions for each extraction of the minimum. I thought about using Fibonacci-Heaps, but I have been told that they are theoretically nice, but suffer from high constants and are pretty complicated to implement. And since insert is in O(log(n)) the runtime increase is nearly constant with large n. So I think its okay to stick to the set. To improve performance I tried to express it in different shapes: return l._cost < r._cost || r._cost > l._cost || l._id < r._id; return l._cost < r._cost || (l._cost == r._cost && l._id < r._id); Even this: typedef union { float _f; int _i; } flint; //... flint diff; diff._f = (l._cost - r._cost); return (diff._i && diff._i >> 31) || l._id < r._id; But the compiler seems to be smart enough already, because I haven't been able to improve the runtime. I also thought about SSE but this problem is really not very applicable for SSE... The assembly looks somewhat like this: movss (%rbx),%xmm1 mov $0x1,%r8d movss 0x20(%rdx),%xmm0 ucomiss %xmm1,%xmm0 ja 0x410600 <_ZNSt8_Rb_tree[..]+96> ucomiss %xmm0,%xmm1 jp 0x4105fd <_ZNSt8_Rb_[..]_+93> jne 0x4105fd <_ZNSt8_Rb_[..]_+93> mov 0x28(%rdx),%rax cmp %rax,0x8(%rbx) jb 0x410600 <_ZNSt8_Rb_[..]_+96> xor %r8d,%r8d I have a very tiny bit experience with assembly language, but not really much. I thought it would be the best (only?) point to squeeze out some performance, but is it really worth the effort? Can you see any shortcuts that could save some cycles? The platform the code will run on is an ubuntu 12 with gcc 4.6 (-stl=c++0x) on a many-core intel machine. Only libraries available are boost, openmp and tbb. I am really stuck on this one, it seems so simple, but takes that much time. I have been crunching my head since days thinking how I could improve this line... Can you give me a suggestion how to improve this part, or is it already at its best?

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  • Javascript style objects in Objective-C

    - by awolf
    Background: I use a ton of NSDictionary objects in my iPhone and iPad code. I'm sick of the verbose way of getting/setting keys to these state dictionaries. So a little bit of an experiment: I just created a class I call Remap. Remap will take any arbitrary set[VariableName]:(NSObject *) obj selector and forward that message to a function that will insert obj into an internal NSMutableDictionary under the key [vairableName]. Remap will also take any (zero argument) arbitrary [variableName] selector and return the NSObject mapped in the NSMutableDictionary under the key [variableName]. e.g. Remap * remap = [[Remap alloc] init]; NSNumber * testNumber = [NSNumber numberWithInt:46]; [remap setTestNumber:testNumber]; testNumber = [remap testNumber]; [remap setTestString:@"test string"]; NSString * testString = [remap testString]; NSMutableDictionary * testDict = [NSMutableDictionary dictionaryWithObject:testNumber forKey:@"testNumber"]; [remap setTestDict:testDict]; testDict = [remap testDict]; where none of the properties testNumber, testString, or testDict are actually defined in Remap. The crazy thing? It works... My only question is how can I disable the "may not respond to " warnings for JUST accesses to Remap? P.S. : I'll probably end up scrapping this and going with macros since message forwarding is quite inefficient... but aside from that does anyone see other problems with Remap? Here's Remap's .m for those who are curious: #import "Remap.h" @interface Remap () @property (nonatomic, retain) NSMutableDictionary * _data; @end @implementation Remap @synthesize _data; - (void) dealloc { relnil(_data); [super dealloc]; } - (id) init { self = [super init]; if (self != nil) { NSMutableDictionary * dict = [[NSMutableDictionary alloc] init]; [self set_data:dict]; relnil(dict); } return self; } - (void)forwardInvocation:(NSInvocation *)anInvocation { NSString * selectorName = [NSString stringWithUTF8String: sel_getName([anInvocation selector])]; NSRange range = [selectorName rangeOfString:@"set"]; NSInteger numArguments = [[anInvocation methodSignature] numberOfArguments]; if (range.location == 0 && numArguments == 4) { //setter [anInvocation setSelector:@selector(setData:withKey:)]; [anInvocation setArgument:&selectorName atIndex:3]; [anInvocation invokeWithTarget:self]; } else if (numArguments == 3) { [anInvocation setSelector:@selector(getDataWithKey:)]; [anInvocation setArgument:&selectorName atIndex:2]; [anInvocation invokeWithTarget:self]; } } - (NSMethodSignature *) methodSignatureForSelector:(SEL) aSelector { NSString * selectorName = [NSString stringWithUTF8String: sel_getName(aSelector)]; NSMethodSignature * sig = [super methodSignatureForSelector:aSelector]; if (sig == nil) { NSRange range = [selectorName rangeOfString:@"set"]; if (range.location == 0) { sig = [self methodSignatureForSelector:@selector(setData:withKey:)]; } else { sig = [self methodSignatureForSelector:@selector(getDataWithKey:)]; } } return sig; } - (NSObject *) getDataWithKey: (NSString *) key { NSObject * returnValue = [[self _data] objectForKey:key]; return returnValue; } - (void) setData: (NSObject *) data withKey:(NSString *)key { if (key && [key length] >= 5 && data) { NSRange range; range.length = 1; range.location = 3; NSString * firstChar = [key substringWithRange:range]; firstChar = [firstChar lowercaseString]; range.length = [key length] - 5; // the 4 we have processed plus the training : range.location = 4; NSString * adjustedKey = [NSString stringWithFormat:@"%@%@", firstChar, [key substringWithRange:range]]; [[self _data] setObject:data forKey:adjustedKey]; } else { //assert? } } @end

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  • ActionScript MovieClip moves to the left, but not the right

    - by Defcon
    I have a stage with a movie clip with the instance name of "mc". Currently I have a code that is suppose to move the player left and right, and when the left or right key is released, the "mc" slides a little bit. The problem I'm having is that making the "mc" move to the left works, but the exact some code used for the right doesn't. All of this code is present on the Main Stage - Frame One //Variables var mcSpeed:Number = 0;//MC's Current Speed var mcJumping:Boolean = false;//if mc is Jumping var mcFalling:Boolean = false;//if mc is Falling var mcMoving:Boolean = false;//if mc is Moving var mcSliding:Boolean = false;//if mc is sliding var mcSlide:Number = 0;//Stored for use when creating slide var mcMaxSlide:Number = 1.6;//Max Distance the object will slide. //Player Move Function p1Move = new Object(); p1Move = function (dir:String, maxSpeed:Number) { if (dir == "left" && _root.mcSpeed<maxSpeed) { _root.mcSpeed += .2; _root.mc._x -= _root.mcSpeed; } else if (dir == "right" && _root.mcSpeed<maxSpeed) { _root.mcSpeed += .2; _root.mc._x += _root.mcSpeed; } else if (dir == "left" && speed>=maxSpeed) { _root.mc._x -= _root.mcSpeed; } else if (dir == "right" && _root.mcSpeed>=maxSpeed) { _root.mc._x += _root.mcSpeed; } } //onEnterFrame for MC mc.onEnterFrame = function():Void { if (Key.isDown(Key.LEFT)) { if (_root.mcMoving == false && _root.mcSliding == false) { _root.mcMoving = true; } else if (_root.mcMoving == true && _root.mcSliding == false) { _root.p1Move("left",5); } } else if (!Key.isDown(Key.LEFT)) { if (_root.mcMoving == true && _root.mcSliding == false) { _root.mcSliding = true; } else if (_root.mcMoving == true && _root.mcSliding == true && _root.mcSlide<_root.mcMaxSlide) { _root.mcSlide += .2; this._x -= .2; } else if (_root.mcMoving == true && _root.mcSliding == true && _root.mcSlide>=_root.mcMaxSlide) { _root.mcMoving = false; _root.mcSliding = false; _root.mcSlide = 0; _root.mcSpeed = 0; } } else if (Key.isDown(Key.RIGHT)) { if (_root.mcMoving == false && _root.mcSliding == false) { _root.mcMoving = true; } else if (_root.mcMoving == true && _root.mcSliding == false) { _root.p1Move("right",5); } } else if (!Key.isDown(Key.RIGHT)) { if (_root.mcMoving == true && _root.mcSliding == false) { _root.mcSliding = true; } else if (_root.mcMoving == true && _root.mcSliding == true && _root.mcSlide<_root.mcMaxSpeed) { _root.mcSlide += .2; this._x += .2; } else if (_root.mcMoving == true && _root.mcSliding == true && _root.mcSlide>=_root.mcMax) { _root.mcMoving = false; _root.mcSliding = false; _root.mcSlide = 0; _root.mcSpeed = 0; } } }; I just don't get why when you press the left arrow its works completely fine, but when you press the right arrow it doesn't respond. It is literally the same code.

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  • LINQ-like or SQL-like DSL for end-users to run queries to select (not modify) data?

    - by Mark Rushakoff
    For a utility I'm working on, the client would like to be able to generate graphic reports on the data that has been collected. I can already generate a couple canned graphs (using ZedGraph, which is a very nice library); however, the utility would be much more flexible if the graphs were more programmable or configurable by the end-user. TLDR version I want users to be able to use something like SQL to safely extract and select data from a List of objects that I provide and can describe. What free tools or libraries will help me accomplish this? Full version I've given thought to using IronPython, IronRuby, and LuaInterface, but frankly they're all a bit overpowered for what I want to do. My classes are fairly simple, along the lines of: class Person: string Name; int HeightInCm; DateTime BirthDate; Weight[] WeighIns; class Weight: int WeightInKg; DateTime Date; Person Owner; (exact classes have been changed to protect the innocent). To come up with the data for the graph, the user will choose whether it's a bar graph, scatter plot, etc., and then to actually obtain the data, I would like to obtain some kind of List from the user simply entering something SQL-ish along the lines of SELECT Name, AVG(WeighIns) FROM People SELECT WeightInKg, Owner.HeightInCm FROM Weights And as a bonus, it would be nice if you could actually do operations as well: SELECT WeightInKg, (Date - Owner.BirthDate) AS Age FROM Weights The DSL doesn't have to be compliant SQL in any way; it doesn't even have to resemble SQL, but I can't think of a more efficient descriptive language for the task. I'm fine filling in blanks; I don't expect a library to do everything for me. What I would expect to exist (but haven't been able to find in any way, shape, or form) is something like Fluent NHibernate (which I am already using in the project) where I can declare a mapping, something like var personRequest = Request<Person>(); personRequest.Item("Name", (p => p.Name)); personRequest.Item("HeightInCm", (p => p.HeightInCm)); personRequest.Item("HeightInInches", (p => p.HeightInCm * CM_TO_INCHES)); // ... var weightRequest = Request<Weight>(); weightRequest.Item("Owner", (w => w.Owner), personRequest); // Indicate a chain to personRequest // ... var people = Table<Person>("People", GetPeopleFromDatabase()); var weights = Table<Weight>("Weights", GetWeightsFromDatabase()); // ... TryRunQuery(userInputQuery); LINQ is so close to what I want to do, but AFAIK there's no way to sandbox it. I don't want to expose any unnecessary functionality to the end user; meaning I don't want the user to be able to send in and process: from p in people select (p => { System.IO.File.Delete("C:\\something\\important"); return p.Name }) So does anyone know of any free .NET libraries that allow something like what I've described above? Or is there some way to sandbox LINQ? cs-script is close too, but it doesn't seem to offer sandboxing yet either. I'd be hesitant to expose the NHibernate interface either, as the user should have a read-only view of the data at this point in the usage. I'm using C# 3.5, and pure .NET solutions would be preferred. The bottom line is that I'm really trying to avoid writing my own parser for a subset of SQL that would only apply to this single project.

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  • UIButton performance in UITableViewCell vs UIView

    - by marcel salathe
    I'd like to add a UIButton to a custom UITableViewCell (programmatically). This is easy to do, but I'm finding that the "performance" of the button in the cell is slow - that is, when I touch the button, there is quite a bit of delay until the button visually goes into the highlighted state. The same type of button on a regular UIView is very responsive in comparison. In order to isolate the problem, I've created two views - one is a simple UIView, the other is a UITableView with only one UITableViewCell. I've added buttons to both views (the UIView and the UITableViewCell), and the performance difference is quite striking. I've searched the web and read the Apple docs but haven't really found the cause of the problem. My guess is that it somehow has to do with the responder chain, but I can't quite put my finger on it. I must be doing something wrong, and I'd appreciate any help. Thanks. Demo code: ViewController.h #import <UIKit/UIKit.h> @interface ViewController : UIViewController <UITableViewDelegate, UITableViewDataSource> @property UITableView* myTableView; @property UIView* myView; ViewController.m #import "ViewController.h" #import "CustomCell.h" @implementation ViewController @synthesize myTableView, myView; - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil { self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]; if (self) { [self initMyView]; [self initMyTableView]; } return self; } - (void) initMyView { UIView* newView = [[UIView alloc] initWithFrame:CGRectMake(0,0,[[UIScreen mainScreen] bounds].size.width,100)]; self.myView = newView; // button on regularView UIButton* myButton = [UIButton buttonWithType:UIButtonTypeRoundedRect]; [myButton addTarget:self action:@selector(pressedMyButton) forControlEvents:UIControlEventTouchUpInside]; [myButton setTitle:@"I'm fast" forState:UIControlStateNormal]; [myButton setFrame:CGRectMake(20.0, 10.0, 160.0, 30.0)]; [[self myView] addSubview:myButton]; } - (void) initMyTableView { UITableView *newTableView = [[UITableView alloc] initWithFrame:CGRectMake(0,100,[[UIScreen mainScreen] bounds].size.width,[[UIScreen mainScreen] bounds].size.height-100) style:UITableViewStyleGrouped]; self.myTableView = newTableView; self.myTableView.delegate = self; self.myTableView.dataSource = self; } -(void) pressedMyButton { NSLog(@"pressedMyButton"); } - (void)viewDidLoad { [super viewDidLoad]; [[self view] addSubview:self.myView]; [[self view] addSubview:self.myTableView]; } - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { return 1; } - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { return 1; } - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { CustomCell *customCell = [tableView dequeueReusableCellWithIdentifier:@"CustomCell"]; if (customCell == nil) { customCell = [[CustomCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:@"CustomCell"]; } return customCell; } @end CustomCell.h #import <UIKit/UIKit.h> @interface CustomCell : UITableViewCell @property (retain, nonatomic) UIButton* cellButton; @end CustomCell.m #import "CustomCell.h" @implementation CustomCell @synthesize cellButton; - (id)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier { self = [super initWithStyle:style reuseIdentifier:reuseIdentifier]; if (self) { // button within cell cellButton = [UIButton buttonWithType:UIButtonTypeRoundedRect]; [cellButton addTarget:self action:@selector(pressedCellButton) forControlEvents:UIControlEventTouchUpInside]; [cellButton setTitle:@"I'm sluggish" forState:UIControlStateNormal]; [cellButton setFrame:CGRectMake(20.0, 10.0, 160.0, 30.0)]; [self addSubview:cellButton]; } return self; } - (void) pressedCellButton { NSLog(@"pressedCellButton"); } @end

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  • Find the right value in recursive array

    - by fire
    I have an array with multiple sub-arrays like this: Array ( [0] => Array ( [Page_ID] => 1 [Page_Parent_ID] => 0 [Page_Title] => Overview [Page_URL] => overview [Page_Type] => content [Page_Order] => 1 ) [1] => Array ( [0] => Array ( [Page_ID] => 2 [Page_Parent_ID] => 1 [Page_Title] => Team [Page_URL] => overview/team [Page_Type] => content [Page_Order] => 1 ) ) [2] => Array ( [Page_ID] => 3 [Page_Parent_ID] => 0 [Page_Title] => Funds [Page_URL] => funds [Page_Type] => content [Page_Order] => 2 ) [3] => Array ( [0] => Array ( [Page_ID] => 4 [Page_Parent_ID] => 3 [Page_Title] => Strategy [Page_URL] => funds/strategy [Page_Type] => content [Page_Order] => 1 ) [1] => Array ( [0] => Array ( [Page_ID] => 7 [Page_Parent_ID] => 4 [Page_Title] => A Class Fund [Page_URL] => funds/strategy/a-class-fund [Page_Type] => content [Page_Order] => 1 ) [1] => Array ( [0] => Array ( [Page_ID] => 10 [Page_Parent_ID] => 7 [Page_Title] => Information [Page_URL] => funds/strategy/a-class-fund/information [Page_Type] => content [Page_Order] => 1 ) [1] => Array ( [Page_ID] => 11 [Page_Parent_ID] => 7 [Page_Title] => Fund Data [Page_URL] => funds/strategy/a-class-fund/fund-data [Page_Type] => content [Page_Order] => 2 ) ) [2] => Array ( [Page_ID] => 8 [Page_Parent_ID] => 4 [Page_Title] => B Class Fund [Page_URL] => funds/strategy/b-class-fund [Page_Type] => content [Page_Order] => 2 ) I need a function to find the right Page_URL so if you know the $url is "funds/strategy/a-class-fund" I need to pass that to a function that returns a single array result (which would be the Page_ID = 7 array in this example). Having a bit of a stupid day, any help would be appreciated!

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  • error in assigning a const character to a usigned char array in C++

    - by mekasperasky
    #include <iostream> #include <fstream> #include <cstring> using namespace std; typedef unsigned long int WORD; /* Should be 32-bit = 4 bytes */ #define w 32 /* word size in bits */ #define r 12 /* number of rounds */ #define b 16 /* number of bytes in key */ #define c 4 /* number words in key */ /* c = max(1,ceil(8*b/w)) */ #define t 26 /* size of table S = 2*(r+1) words */ WORD S [t],L[c]; /* expanded key table */ WORD P = 0xb7e15163, Q = 0x9e3779b9; /* magic constants */ /* Rotation operators. x must be unsigned, to get logical right shift*/ #define ROTL(x,y) (((x)<<(y&(w-1))) | ((x)>>(w-(y&(w-1))))) #define ROTR(x,y) (((x)>>(y&(w-1))) | ((x)<<(w-(y&(w-1))))) void RC5_DECRYPT(WORD *ct, WORD *pt) /* 2 WORD input ct/output pt */ { WORD i, B=ct[1], A=ct[0]; for (i=r; i>0; i--) { B = ROTR(B-S [2*i+1],A)^A; A = ROTR(A-S [2*i],B)^B; } pt [1] = B-S [1] ;pt [0] = A-S [0]; } void RC5_SETUP(unsigned char *K) /* secret input key K 0...b-1] */ { WORD i, j, k, u=w/8, A, B, L [c]; /* Initialize L, then S, then mix key into S */ for (i=b-1,L[c-1]=0; i!=-1; i--) L[i/u] = (L[i/u]<<8)+K[ i]; for (S [0]=P,i=1; i<t; i++) S [i] = S [i-1]+Q; for (A=B=i=j=k=0; k<3*t; k++,i=(i+1)%t,j=(j+1)%c) /* 3*t > 3*c */ { A = S[i] = ROTL(S [i]+(A+B),3); B = L[j] = ROTL(L[j]+(A+B),(A+B)); } } void printword(WORD A) { WORD k; for (k=0 ;k<w; k+=8) printf("%02.2lX",(A>>k)&0xFF); } int main() { WORD i, j, k, pt [2], pt2 [2], ct [2] = {0,0}; unsigned char key[b]; ofstream out("cpt.txt"); ifstream in("key.txt"); if(!in) { cout << "Cannot open file.\n"; return 1; } if(!out) { cout << "Cannot open file.\n"; return 1; } key="111111000001111"; RC5_SETUP(key); ct[0]=2185970173; ct[1]=3384368406; for (i=1;i<2;i++) { RC5_DECRYPT(ct,pt2); printf("\n plaintext "); printword(pt [0]); printword(pt[1]); } return 0; } when i run this code i get two warnings and also an error saying that i cant assign a char value to my character array . Why is that ?

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  • Is it possible to shuffle a 2D matrix while preserving row AND column frequencies?

    - by j_random_hacker
    Suppose I have a 2D array like the following: GACTG AGATA TCCGA Each array element is taken from a small finite set (in my case, DNA nucleotides -- {A, C, G, T}). I would like to randomly shuffle this array somehow while preserving both row and column nucleotide frequencies. Is this possible? Can it be done efficiently? [EDIT]: By this I mean I want to produce a new matrix where each row has the same number of As, Cs, Gs and Ts as the corresponding row of the original matrix, and where each column has the same number of As, Cs, Gs and Ts as the corresponding column of the original matrix. Permuting the rows or columns of the original matrix will not achieve this in general. (E.g. for the example above, the top row has 2 Gs, and 1 each of A, C and T; if this row was swapped with row 2, the top row in the resulting matrix would have 3 As, 1 G and 1 T.) It's simple enough to preserve just column frequencies by shuffling a column at a time, and likewise for rows. But doing this will in general alter the frequencies of the other kind. My thoughts so far: If it's possible to pick 2 rows and 2 columns so that the 4 elements at the corners of this rectangle have the pattern XY YX for some pair of distinct elements X and Y, then replacing these 4 elements with YX XY will maintain both row and column frequencies. In the example at the top, this can be done for (at least) rows 1 and 2 and columns 2 and 5 (whose corners give the 2x2 matrix AG;GA), and for rows 1 and 3 and columns 1 and 4 (whose corners give GT;TG). Clearly this could be repeated a number of times to produce some level of randomisation. Generalising a bit, any "subrectangle" induced by a subset of rows and a subset of columns, in which the frequencies of all rows are the same and the frequencies of all columns are the same, can have both its rows and columns permuted to produce a valid complete rectangle. (Of these, only those subrectangles in which at least 1 element is changed are actually interesting.) Big questions: Are all valid complete matrices reachable by a series of such "subrectangle rearrangements"? I suspect the answer is yes. Are all valid subrectangle rearrangements decomposable into a series of 2x2 swaps? I suspect the answer is no, but I hope it's yes, since that would seem to make it easier to come up with an efficient algorithm. Can some or all of the valid rearrangements be computed efficiently? This question addresses a special case in which the set of possible elements is {0, 1}. The solutions people have come up with there are similar to what I have come up with myself, and are probably usable, but not ideal as they require an arbitrary amount of backtracking to work correctly. Also I'm concerned that only 2x2 swaps are considered. Finally, I would ideally like a solution that can be proven to select a matrix uniformly at random from the set of all matrices having identical row frequencies and column frequencies to the original. I know, I'm asking for a lot :)

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  • Please clarify how create/update happens against child entities of an aggregate root

    - by christian
    After much reading and thinking as I begin to get my head wrapped around DDD, I am a bit confused about the best practices for dealing with complex hierarchies under an aggregate root. I think this is a FAQ but after reading countless examples and discussions, no one is quite talking about the issue I'm seeing. If I am aligned with the DDD thinking, entities below the aggregate root should be immutable. This is the crux of my trouble, so if that isn't correct, that is why I'm lost. Here is a fabricated example...hope it holds enough water to discuss. Consider an automobile insurance policy (I'm not in insurance, but this matches the language I hear when on the phone w/ my insurance company). Policy is clearly an entity. Within the policy, let's say we have Auto. Auto, for the sake of this example, only exists within a policy (maybe you could transfer an Auto to another policy, so this is potential for an aggregate as well, which changes Policy...but assume it simpler than that for now). Since an Auto cannot exist without a Policy, I think it should be an Entity but not a root. So Policy in this case is an aggregate root. Now, to create a Policy, let's assume it has to have at least one auto. This is where I get frustrated. Assume Auto is fairly complex, including many fields and maybe a child for where it is garaged (a Location). If I understand correctly, a "create Policy" constructor/factory would have to take as input an Auto or be restricted via a builder to not be created without this Auto. And the Auto's creation, since it is an entity, can't be done beforehand (because it is immutable? maybe this is just an incorrect interpretation). So you don't get to say new Auto and then setX, setY, add(Z). If Auto is more than somewhat trivial, you end up having to build a huge hierarchy of builders and such to try to manage creating an Auto within the context of the Policy. One more twist to this is later, after the Policy is created and one wishes to add another Auto...or update an existing Auto. Clearly, the Policy controls this...fine...but Policy.addAuto() won't quite fly because one can't just pass in a new Auto (right!?). Examples say things like Policy.addAuto(VIN, make, model, etc.) but are all so simple that that looks reasonable. But if this factory method approach falls apart with too many parameters (the entire Auto interface, conceivably) I need a solution. From that point in my thinking, I'm realizing that having a transient reference to an entity is OK. So, maybe it is fine to have a entity created outside of its parent within the aggregate in a transient environment, so maybe it is OK to say something like: auto = AutoFactory.createAuto(); auto.setX auto.setY or if sticking to immutability, AutoBuilder.new().setX().setY().build() and then have it get sorted out when you say Policy.addAuto(auto) This insurance example gets more interesting if you add Events, such as an Accident with its PolicyReports or RepairEstimates...some value objects but most entities that are all really meaningless outside the policy...at least for my simple example. The lifecycle of Policy with its growing hierarchy over time seems the fundamental picture I must draw before really starting to dig in...and it is more the factory concept or how the child entities get built/attached to an aggregate root that I haven't seen a solid example of. I think I'm close. Hope this is clear and not just a repeat FAQ that has answers all over the place.

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  • Haskell Monad bind currying

    - by Chime
    I am currently in need of a bit of brain training and I found this article on Haskell and Monads I'm having trouble with exercise 7 re. Randomised function bind. To make the problem even simpler to experiment, I replaced the StdGen type with an unspecified type. So instead of... bind :: (a -> StdGen -> (b,StdGen)) -> (StdGen -> (a,StdGen)) -> (StdGen -> (b,StdGen)) I used... bind :: (a -> c -> (b,c)) -> (c -> (a,c)) -> (c -> (b,c)) and for the actual function impelemtation (just straight from the exercise) bind f x seed = let (x',seed') = x seed in f x' seed' and also 2 randomised functions to trial with: rndf1 :: (Num a, Num b) => a -> b -> (a,b) rndf1 a s = (a+1,s+1) rndf2 :: (Num a, Num b) => a -> b -> (a,b) rndf2 a s = (a+8,s+2) So with this in a Haskell compiler (ghci), I get... :t bind rndf2 bind rndf2 :: (Num a, Num c) => (c -> (a, c)) -> c -> (a, c) This matches the bind curried with rndf2 as the first parameter. But the thing I don't understand is how... :t bind rndf2 . rndf1 Suddenly gives bind rndf2 . rndf1 :: (Num a, Num c) => a -> c -> (a, c) This is the correct type of the composition that we are trying to produce because bind rndf2 . rndf1 Is a function that: takes the same parameter type(s) as rndf1 AND takes the return from rndf1 and pipes it as an input of rndf2 to return the same type as rndf2 rndf1 can take 2 parameters a -> c and rndf2 returns (a, c) so it matches that a composition of these function should have type: bind rndf2 . rndf1 :: (Num a, Num c) => a -> c -> (a, c) This does not match the naive type that I initially came up with for bind bind f :: (a -> b -> (c, d)) -> (c, d) -> (e, f) Here bind mythically takes a function that takes two parameters and produces a function that takes a tuple in order that the output from rndf1 can be fed into rndf2 why the bind function needs to be coded as it is Why the bind function does not have the naive type

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