Search Results

Search found 50550 results on 2022 pages for 'method resolution order'.

Page 297/2022 | < Previous Page | 293 294 295 296 297 298 299 300 301 302 303 304  | Next Page >

• C# mysql one return last_insert_id

  - by Bernhard

  I am trying to create a method in which I can exequte mysql UPDATE, DELETE or INSERT query. The method must work when with an INSERT I ask or do not ask the last_insert_id(). Below is the code that I have at the moment: public int executeUID(MySqlCommand msCommand) { try { this.Open(); msCommand.Connection = this.msCon; return int.Parse(msCommand.ExecuteScalar().ToString()); } catch (MySqlException ex) { throw ex; } finally { this.Close(); } } The problem with this is is that when I use an insert query that returns a last_insert_id() the method works greatly. But when the query doesn't return an last_insert_id() the method malfunctions. How can I get this method to work?

  Read the article

• Mysql question about UPDATE

  - by Beck

  UPDATE counter_reports SET `counter`=`counter`+1,`date`=? WHERE report_id IN( (SELECT report_id FROM counter_reports WHERE report_name="emails_sent" AND `year`=1 ORDER BY report_id DESC LIMIT 1), (SELECT report_id FROM counter_reports WHERE report_name="emails_sent" AND `month`=1 ORDER BY report_id DESC LIMIT 1), (SELECT report_id FROM counter_reports WHERE report_name="emails_sent" AND `week`=1 ORDER BY report_id DESC LIMIT 1), (SELECT report_id FROM counter_reports WHERE report_name="emails_sent" AND `day`=1 ORDER BY report_id DESC LIMIT 1) ) Is there any alternative for such sql? I need to update(increment by 1) last counter reports for day,week,month and year. If I'm adding manually, sql works fine, but with subqueries it fails to launch. Thanks. :)

  Read the article

• Strangest LINQ to SQL case I have ever seen

  - by kubaw

  OK, so this is the strangest issue in .net programming I have ever seen. It seems that object fields are serialized in .net web services in order of field initialization. It all started with Flex not accepting SOAP response from .net web service. I have found out that it was due to the order of serialized fields was statisfying the order of fields in declared serializable class. It had something to do with generic lists and LINQ to SQL but I can't find out what. This one is really hard to reproduce. Example to get the idea: [Serializable] public class SomeSample { public int A; public int B; public int C; } I was querying some data tables within asmx web service using linq and returning list of SomeSample objects: var r = (from ...... select new SomeSample { A = 1, C = 3 }).ToList(); Now the list was once more iterated and B field was applied some value (ex. 2). However the returned soap envelope contained following excerpt: <A>1</A><C>3</C><B>2</B> Please notice the order of serialization. If I initially initialized all fields: var r = (from ...... select new SomeSample { A = 1, B = 2, C = 3 }).ToList(); object was serialized in correct order. I must add, that in both cases the debugger shows exactly the same content of "r" variable. Am I losing my mind or is this normal behavior? Thanks in advance.

  Read the article

• PHP sort multidimensional array by value

  - by stef

  How can I sort this array by the value of the "order" key? Even though the values are currently sequential, they will not always be. Array ( [0] => Array ( [hashtag] => a7e87329b5eab8578f4f1098a152d6f4 [title] => Flower [order] => 3 ) [1] => Array ( [hashtag] => b24ce0cd392a5b0b8dedc66c25213594 [title] => Free [order] => 2 ) [2] => Array ( [hashtag] => e7d31fc0602fb2ede144d18cdffd816b [title] => Ready [order] => 1 ) )

  Read the article

• JQUERY - how to get updated value after ajax removes data from within it?

  - by Brian

  I have a an element with thumbnails. I allow users to sort their display order (which fires off an update to the DB via ajax). I also allow them to delete images (which, after deletion, fires off a request to update the display order for all remaining images). My problem is with binding or live I think, but I don't know where to apply it. The array fired off upon delete contains ALL the ids for the images that were there on page load. The issue is that after they delete an image the array STILL contains the original ids (including the one that was deleted) so it is obviously not refreshing the value of the element after ajax has removed things from inside it. I need to tell it to go get the refreshed contents... From what I have been reading, this is normal but I don't understand how to tie it into my routine. I need to trigger the mass re-ordering after any deletion. Any ideas gurus? $('a.delimg').click(function(){ var parent = $(this).parent().parent(); var id = $(this).attr('id'); $.ajax({ type: "POST", url: "../updateImages.php", data: "action=delete&id=" + id, beforeSend: function() { parent.animate({'backgroundColor':'#fb6c6c'},300); $.jnotify("<strong>Deleting This Image & Updating The Image Order</strong>", 5000); }, success: function(data) { parent.slideUp(300,function() { parent.remove(); $("#images ul").sortable(function() { //NEEDS TO GET THE UPDATED CONTENT var order = $(this).sortable("serialize") + '&action=updateRecordsListings'; $.post("../updateImages.php", order, function(theResponse){ $.jnotify("<strong>" + theResponse + "</strong>", 2000); }); }); }); } }); return false; }); Thanks for any help you can be.

  Read the article

• Can anyone decipher this for me? PHP (I think)

  - by Josh

  This code is being used to parse email, it's stored as a table in a mySQL database. I believe it's PHP code. What does the (.+) do? /A new order has been successfully placed through(.+)Name:(.+)Company:(.+)Email:(.+)Address 1(.+)Order ID:(.+)Date:(.+)Payment Type:(.+)Order Status:(\s*)Accepted(.*)\n(.+)\$([\d\.]+)\s+X/si Thanks, super-brainiacs!

  Read the article

• Using jQuery .find() with multiple conditions at the same time?

  - by fuzzybabybunny

  I know that there are other ways of grabbing radio button values, but I want to know how to do this with .find(). I only want to log the value of the selected radio button, so it requires finding by two conditions at the same time: The button with name=area The button with selected=selected <div class="radio"> <label> <input class="track-order-change" type="radio" name="area" id="area1" value="area1" checked="checked"> Area 1 </label> </div> <div class="radio"> <label> <input class="track-order-change" type="radio" name="area" id="area2" value="area2"> Area 2 </label> </div> <div class="radio"> <label> <input class="track-order-change" type="radio" name="area" id="area3" value="area3"> Area 3 </label> </div> When anything with the class track-order-change changes, it will run the function UpdateOrderSubmission. $('.track-order-change').on('change', function() { updateOrderSubmission() }); I want the updateOrderSubmission function to console log the value of the radio button that is selected. var updateOrderSubmission = function() { var orderSubmission = { area: $('#submit-initial-form').find('[name=area],[checked=checked]').this.val() } console.log(orderSubmission) }; The code above doesn't work. How do I grab the value of the selected radio button? I need to do .find() with two conditions (name and checked), not just one condition.

  Read the article

• Multiple &(AND) fails in query

  - by N e w B e e

  here is my query $sql = 'SELECT * FROM Orders INNER JOIN [Order Details] ON Orders.OrderNumber = [Order Details].OrderNumber WHERE Orders.CartID =2 AND [Order Details].Option10 Is Null AND [Order Details].Status="Shipped"'; this queries when entered in MS_Access sql view, returns the correct results, but when I copy and paste the same query in my php script, it fails and gives the error Too few parameters, expected 1... although data is there, query is working in access... Please note if I omitted on AND condition, it works eg if I removed shipped conidtion or is null condition, it works then too.. any hint? whats wrong with it?? any help?thanks

  Read the article

• Java Programming Help

  - by user215049

  hi, im a bit confused on this and i dont know how to solve this question that i have been asked, id be grateful if you could assist me on this question, maybe try to tell me what needs to be done, and how. the question is: Write a method called countChars which takes an InputStream as a parameter, reads the stream and returns the number of characters it contains as an int. Any IOExceptions which might occur in the method should be passed back to the method's caller. Note that the method header should show that it is possible that an exception might occur. i attempted this question with the following code: public class countChars { public int countChars(int InputStream) { return InputStream; } } and i get an error message saying : Main.java:26: cannot find symbol symbol : method countChars(java.io.InputStream) location: class Main s1 = "" + countChars(f1); ^ 1 error

  Read the article

• When should methods be made private?

  - by AaronSzy

  There are lots of times where i'm not sure whether a particular method should be made private or not. For example, i'm building a class right now, which, is responsible for generating a report. This class has a buildReport method and several methods which collect the necessary data for buildReport. // single public method // uses a set of helper methods public buildReport() // helper methods private avgSurveyTime() private fetchVendors() private fetchSendCounts() private ... Im debating whether i should make these helper methods public. The only method i really plan on calling outside at the moment is buildReport. However, it might be useful to get just a list of the vendors with fetchVendors etc. I see two schools of thought on this: You can always expose as little as possible. (In which case, many of my classes would only have one public method) OR you can expose all you can that might be useful to the user of the class. Is there a good rule of thumb to use for deciding when methods should be made public/private?

  Read the article

• prescription nolvadex pharmacy

  - by prescription nolvadex pharmacy

  Discount system Fast worldwide shipping No prescription required Special internet price 24/7/365 costumer support TO BUY NOLVADEX CLICK HERE Related tags:Nolvadex buy nolvadex nolvadex no prescription purchase nolvadex order nolvadex online buy nolvadex d 20 buy nolvadex no prescription buy nolvadex tamoxifen citrate cheap nolvadex no prescription buy nolvadex estrogen order nolvadex online generic nolvadex prescription buy nolvadex online prescription nolvadex pharmacy order nolvadex

  Read the article

• @MustOverride annotation?

  - by Harrypotter2k5

  In .NET, one can specify a "mustoverride" attribute to a method in a particular superclass to ensure that subclasses override that particular method. I was wondering whether anybody has a custom java annotation that could achieve the same effect. Essentially what i want is to push for subclasses to override a method in a superclass that itself has some logic that must be run-through. I dont want to use abstract methods or interfaces, because i want some common functionality to be run in the super method, but more-or-less produce a compiler warning/error denoting that derivative classes should override a given method.

  Read the article

• Retrieving Json Array

  - by Rahul Varma

  Hi, I am trying to retrieve the values from the following url: http://rentopoly.com/ajax.php?query=Bo. I want to get the values of all the suggestions to be displayed in a list view one by one. This is how i want to do... public class AlertsAdd { public ArrayList<JSONObject> retrieveJSONArray(String urlString) { String result = queryRESTurl(urlString); ArrayList<JSONObject> ALERTS = new ArrayList<JSONObject>(); if (result != null) { try { JSONObject json = new JSONObject(result); JSONArray alertsArray = json.getJSONArray("suggestions"); for (int a = 0; a < alertsArray.length(); a++) { JSONObject alertitem = alertsArray.getJSONObject(a); ALERTS.add(alertitem); } return ALERTS; } catch (JSONException e) { Log.e("JSON", "There was an error parsing the JSON", e); } } JSONObject myObject = new JSONObject(); try { myObject.put("suggestions",myObject.getJSONArray("suggestions")); ALERTS.add(myObject); } catch (JSONException e1) { Log.e("JSON", "There was an error creating the JSONObject", e1); } return ALERTS; } private String queryRESTurl(String url) { // URLConnection connection; HttpClient httpclient = new DefaultHttpClient(); HttpGet httpget = new HttpGet(url); HttpResponse response; try { response = httpclient.execute(httpget); HttpEntity entity = response.getEntity(); if (entity != null) { InputStream instream = entity.getContent(); String result = convertStreamToString(instream); instream.close(); return result; } } catch (ClientProtocolException e) { Log.e("REST", "There was a protocol based error", e); } catch (IOException e) { Log.e("REST", "There was an IO Stream related error", e); } return null; } /** * To convert the InputStream to String we use the * BufferedReader.readLine() method. We iterate until the BufferedReader * return null which means there's no more data to read. Each line will * appended to a StringBuilder and returned as String. */ private String convertStreamToString(InputStream is) { BufferedReader reader = new BufferedReader(new InputStreamReader(is)); StringBuilder sb = new StringBuilder(); String line = null; try { while ((line = reader.readLine()) != null) { sb.append(line + "\n"); } } catch (IOException e) { e.printStackTrace(); } finally { try { is.close(); } catch (IOException e) { e.printStackTrace(); } } return sb.toString(); } } Here's the adapter code... public class AlertsAdapter extends ArrayAdapter<JSONObject> { public AlertsAdapter(Activity activity, List<JSONObject> alerts) { super(activity, 0, alerts); } @Override public View getView(int position, View convertView, ViewGroup parent) { Activity activity = (Activity) getContext(); LayoutInflater inflater = activity.getLayoutInflater(); View rowView = inflater.inflate(R.layout.list_text, null); JSONObject imageAndText = getItem(position); TextView textView = (TextView) rowView.findViewById(R.id.last_build_stat); try { textView.setText((String)imageAndText.get("suggestions")); } catch (JSONException e) { textView.setText("JSON Exception"); } return rowView; } } Here's the logcat... 04-30 13:09:46.656: INFO/ActivityManager(584): Starting activity: Intent { act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] flg=0x10000000 cmp=com.WorldToyota/.Alerts } 04-30 13:09:50.417: ERROR/JSON(924): There was an error parsing the JSON 04-30 13:09:50.417: ERROR/JSON(924): org.json.JSONException: JSONArray[0] is not a JSONObject. 04-30 13:09:50.417: ERROR/JSON(924): at org.json.JSONArray.getJSONObject(JSONArray.java:268) 04-30 13:09:50.417: ERROR/JSON(924): at com.WorldToyota.AlertsAdd.retrieveJSONArray(AlertsAdd.java:30) 04-30 13:09:50.417: ERROR/JSON(924): at com.WorldToyota.Alerts.onCreate(Alerts.java:20) 04-30 13:09:50.417: ERROR/JSON(924): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1123) 04-30 13:09:50.417: ERROR/JSON(924): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2364) 04-30 13:09:50.417: ERROR/JSON(924): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2417) 04-30 13:09:50.417: ERROR/JSON(924): at android.app.ActivityThread.access$2100(ActivityThread.java:116) 04-30 13:09:50.417: ERROR/JSON(924): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1794) 04-30 13:09:50.417: ERROR/JSON(924): at android.os.Handler.dispatchMessage(Handler.java:99) 04-30 13:09:50.417: ERROR/JSON(924): at android.os.Looper.loop(Looper.java:123) 04-30 13:09:50.417: ERROR/JSON(924): at android.app.ActivityThread.main(ActivityThread.java:4203) 04-30 13:09:50.417: ERROR/JSON(924): at java.lang.reflect.Method.invokeNative(Native Method) 04-30 13:09:50.417: ERROR/JSON(924): at java.lang.reflect.Method.invoke(Method.java:521) 04-30 13:09:50.417: ERROR/JSON(924): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791) 04-30 13:09:50.417: ERROR/JSON(924): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549) 04-30 13:09:50.417: ERROR/JSON(924): at dalvik.system.NativeStart.main(Native Method) 04-30 13:09:50.688: ERROR/JSON(924): There was an error creating the JSONObject 04-30 13:09:50.688: ERROR/JSON(924): org.json.JSONException: JSONObject["suggestions"] not found. 04-30 13:09:50.688: ERROR/JSON(924): at org.json.JSONObject.get(JSONObject.java:287) 04-30 13:09:50.688: ERROR/JSON(924): at org.json.JSONObject.getJSONArray(JSONObject.java:362) 04-30 13:09:50.688: ERROR/JSON(924): at com.WorldToyota.AlertsAdd.retrieveJSONArray(AlertsAdd.java:41) 04-30 13:09:50.688: ERROR/JSON(924): at com.WorldToyota.Alerts.onCreate(Alerts.java:20) 04-30 13:09:50.688: ERROR/JSON(924): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1123) 04-30 13:09:50.688: ERROR/JSON(924): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2364) 04-30 13:09:50.688: ERROR/JSON(924): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2417) 04-30 13:09:50.688: ERROR/JSON(924): at android.app.ActivityThread.access$2100(ActivityThread.java:116) 04-30 13:09:50.688: ERROR/JSON(924): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1794) 04-30 13:09:50.688: ERROR/JSON(924): at android.os.Handler.dispatchMessage(Handler.java:99) 04-30 13:09:50.688: ERROR/JSON(924): at android.os.Looper.loop(Looper.java:123) 04-30 13:09:50.688: ERROR/JSON(924): at android.app.ActivityThread.main(ActivityThread.java:4203) 04-30 13:09:50.688: ERROR/JSON(924): at java.lang.reflect.Method.invokeNative(Native Method) 04-30 13:09:50.688: ERROR/JSON(924): at java.lang.reflect.Method.invoke(Method.java:521) 04-30 13:09:50.688: ERROR/JSON(924): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791) 04-30 13:09:50.688: ERROR/JSON(924): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549) 04-30 13:09:50.688: ERROR/JSON(924): at dalvik.system.NativeStart.main(Native Method) Plz help me parsing this script and displaying the values in list format....

  Read the article

• Yet another (13)Permission denied error on Apache2 server

  - by lollercoaster

  I just can't figure it out. I'm running apache2 on a Ubuntu 10.04 i386 server. Whenever I visit my server (has an IP address, and is connected to internet with static IP xxx.xxx.xxx.xxx) so that's not the problem) in browser, mysub.domain.edu (renamed here), I get the following: Forbidden You don't have permission to access /index.html on this server The apache2 error log confirms this: [Mon Apr 18 02:38:20 2011] [error] [client zzz.zzz.zzz.zzz] (13)Permission denied: access to / denied I'll try to provide all necessary information below: 1) Contents of /etc/apache2/httpd.conf DirectoryIndex index.html index.php 2) Contents of /etc/apache2/sites-available/default <VirtualHost *:80> ServerAdmin [email protected] DocumentRoot /home/myusername/htdocs <Directory /> Options FollowSymLinks AllowOverride None </Directory> <Directory "/home/myusername/htdocs/"> Options Indexes FollowSymLinks MultiViews AllowOverride None order allow,deny allow from all DirectoryIndex index.html index.php Satisfy any </Directory> ScriptAlias /cgi-bin/ /usr/lib/cgi-bin/ <Directory "/usr/lib/cgi-bin"> AllowOverride None Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch Order allow,deny Allow from all </Directory> ErrorLog /var/log/apache2/error.log # Possible values include: debug, info, notice, warn, error, crit, # alert, emerg. LogLevel warn CustomLog /var/log/apache2/access.log combined Alias /doc/ "/usr/share/doc/" <Directory "/usr/share/doc/"> Options Indexes MultiViews FollowSymLinks AllowOverride None Order deny,allow Deny from all Allow from 127.0.0.0/255.0.0.0 ::1/128 </Directory> ServerName mysub.domain.edu </VirtualHost> 3) Contents of /etc/apache2/sites-enabled/000-default <VirtualHost *:80> ServerAdmin [email protected] DocumentRoot /home/myusername/htdocs <Directory /> Options FollowSymLinks AllowOverride None </Directory> <Directory "/home/myusername/htdocs/"> Options Indexes FollowSymLinks MultiViews AllowOverride None order allow,deny allow from all DirectoryIndex index.html index.php Satisfy any </Directory> ScriptAlias /cgi-bin/ /usr/lib/cgi-bin/ <Directory "/usr/lib/cgi-bin"> AllowOverride None Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch Order allow,deny Allow from all </Directory> ErrorLog /var/log/apache2/error.log # Possible values include: debug, info, notice, warn, error, crit, # alert, emerg. LogLevel warn CustomLog /var/log/apache2/access.log combined Alias /doc/ "/usr/share/doc/" <Directory "/usr/share/doc/"> Options Indexes MultiViews FollowSymLinks AllowOverride None Order deny,allow Deny from all Allow from 127.0.0.0/255.0.0.0 ::1/128 </Directory> ServerName mysub.domain.edu </VirtualHost> 4) Result of ls -l (when I'm using sudo -i to be root): root@myserver:/home/myusername# ls -l total 4 drwxr-xr-x 2 www-data root 4096 2011-04-18 03:04 htdocs 5) ps auxwww | grep -i apache root@myserver:/home# ps auxwww | grep -i apache root 15121 0.0 0.4 5408 2544 ? Ss 16:55 0:00 /usr/sbin/apache2 -k start www-data 15122 0.0 0.3 5180 1760 ? S 16:55 0:00 /usr/sbin/apache2 -k start www-data 15123 0.0 0.5 227020 2788 ? Sl 16:55 0:00 /usr/sbin/apache2 -k start www-data 15124 0.0 0.5 227020 2864 ? Sl 16:55 0:00 /usr/sbin/apache2 -k start root 29133 0.0 0.1 3320 680 pts/0 R+ 16:58 0:00 grep --color=auto -i apache 6) ls -al /home/myusername/htdocs/ root@myserver:/# ls -al /home/myusername/htdocs/ total 20 drwxr-xr-x 2 www-data root 4096 2011-04-18 03:04 . drw-r--r-- 4 myusername myusername 4096 2011-04-18 02:13 .. -rw-r--r-- 1 root root 69 2011-04-18 02:14 index.html I'm not currently using any .htaccess files in my web root (htdocs) folder in my user folder. I don't know what is wrong, I've been trying to fix his for over 12 hours and I've gotten nowhere. If you have any suggestions, I'm all ears...

  Read the article

• Multiple Homed Windows 2008 Server / Windows 7 Client

  - by Daniel Scott

  I have a small Windows 2008 network, with some Windows 7 clients. The clients are both laptops with docking stations and I would like them to communicate with the Windows 2008 server (for filesharing) through the wired network whilst they're docked. Internet connectivity for all machines (clients and server) is via a Wireless LAN, so the wireless adapter in the Windows 7 clients stays active while they're docked. When the laptops are un-docked, it would be nice to still be able to contact the windows 2008 server for print sharing (and slower file sharing) - hence the server also being on the wireless LAN. The windows 2008 server is running Active Directory, DHCP and DNS. It controls DHCP leases on the wired network and holds the DNS records for "myserver.mycompany.local", which is what the filesharing clients connect to. Ideally I'd like the DNS records to return the wired IP first so that this is the address that the laptops will attempt initially - but there doesn't seem to be a way to do that? At present the server's IP on the wireless LAN comes out of an nslookup above the wired Lan IP. The multi-homing works perfectly - but in the wrong order! Switch on the wireless lan and ping myserver and it goes to the wireless IP. Disable the wireless on the client and do the same ping again and after a couple of seconds it starts pinging the wired address. Does anyone have any suggestions on how to make this work in a predictable order? - or even if it can work. Alternative 1? If it can't work, then would this work: Remove the wireless adapter from the server, put a wireless router/bridge on the wired network (set up to route to/from the wireless LAN's subnet), then configure the clients with two routes to the (now) single IP of the server with metrics favouring direct communication over the wired LAN first? Alternative 2? Should I instead single-home the laptops so all of their connectivity is via the wired-LAN while they're docked? (and route via the windows 2008 server - or a dedicated wireless bridge/router)? My concern here is that I'd like undocking to be seamless - and if the clients are in the middle of downloading something from the internet I wouldn't want whatever they're doing interupted as they switch IP addresses onto the Wireless network. Perhaps this isn't the case and I'm concerned over nothing? Any thoughts? :) UPDATE I seem to have cracked it (at least DNS entries come out in the order I hope for - and pinging the server with various combinations of wired, wireless and both interfaces enabled uses the IP I want) ... I set the binding order of the NICs on the Server (which is acting as Domain Controller, DHCP and DNS server) so that the Wired NIC is before the Wireless adapter. (Start -- type "Network Interfaces" -- Select "View Network Connections" -- Press Alt to show classic dropdown menus -- Advanced -- Advanced Settings) Now, an nslookup (from the client) of the server's hostname returns the Wired IP first, followed by the Wireless IP. The wired IP now seems to be used whenever it's contactable. Incidentally, the metrics on the wired and wireless routes (on the client) also favour the wired LAN (based on Windows' automatically assigned metrics) - but this was always the case, even when I was having trouble getting the wired IP to be "favoured". I'm not entirely sure if this is coincidence - or if a DNS server running on Windows, handing back IP addresses for itself does actually take the binding order of it's own network interfaces into account? It would be interesting to hear from someone who can confirm or deny that (or confirm that the binding order on the server plays a role for some other reason?)

  Read the article

• Apache, ISPConfig & Roundcube alias

  - by Jay Zus

  I'm using ISPConfig to setup all the websites on my server but I also like to try to fiddle with the files myself to see how it works. Like you guessed, yes, I've broken something. I can't access my webmail setup by default on the server with the alias /webmail (I access it via the http://xxx.xxx.xx.xx/webmail) Firefox tells me that The page isn't redirecting properly Firefox has detected that the server is redirecting the request for this address in a way that will never complete. So I cleaned up my vhost files and the one of my websites work as intended, I think that the problem comes from my default.vhost. Here's the content of it <Directory /var/www/> AllowOverride None Order Deny,Allow Deny from all </Directory> <VirtualHost *:80> DocumentRoot /var/www/ ServerAdmin [email protected] <Directory /var/www/> Options FollowSymLinks AllowOverride All Order allow,deny Allow from all </Directory> </VirtualHost> This isn't a lot and I can't really see what's wrong with it, all I know is that it isn't the one that came with ISPConfig and I can't find an original one. Here's the roundcube.conf that loads with apache # Those aliases do not work properly with several hosts on your apache server # Uncomment them to use it or adapt them to your configuration # Alias /roundcube/program/js/tiny_mce/ /usr/share/tinymce/www/ # Alias /roundcube /var/lib/roundcube Alias /webmail /var/lib/roundcube/ # Access to tinymce files <Directory "/usr/share/tinymce/www/"> Options Indexes MultiViews FollowSymLinks AllowOverride None Order allow,deny allow from all </Directory> <Directory /var/lib/roundcube/> Options +FollowSymLinks # This is needed to parse /var/lib/roundcube/.htaccess. See its # content before setting AllowOverride to None. AllowOverride All order allow,deny allow from all </Directory> # Protecting basic directories: <Directory /var/lib/roundcube/config> Options -FollowSymLinks AllowOverride None </Directory> <Directory /var/lib/roundcube/temp> Options -FollowSymLinks AllowOverride None Order allow,deny Deny from all </Directory> <Directory /var/lib/roundcube/logs> Options -FollowSymLinks AllowOverride None Order allow,deny Deny from all </Directory> I didn't touch that file, but I guess it has something to do with the problem. I just can't find why it doesn't work. EDIT: This is the errors in my apache's log [21/Jun/2013:21:10:54 +0200] "GET /webmail/ HTTP/1.1" 302 540 "-" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:21.0) Gecko/20100101 Firefox/21.0" [21/Jun/2013:21:10:54 +0200] "GET /webmail/ HTTP/1.1" 302 475 "-" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:21.0) Gecko/20100101 Firefox/21.0" [21/Jun/2013:21:10:54 +0200] "GET /webmail/ HTTP/1.1" 302 475 "-" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:21.0) Gecko/20100101 Firefox/21.0" [21/Jun/2013:21:10:54 +0200] "GET /webmail/ HTTP/1.1" 302 475 "-" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:21.0) Gecko/20100101 Firefox/21.0" [21/Jun/2013:21:10:54 +0200] "GET /webmail/ HTTP/1.1" 302 475 "-" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:21.0) Gecko/20100101 Firefox/21.0" [21/Jun/2013:21:10:54 +0200] "GET /webmail/ HTTP/1.1" 302 475 "-" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:21.0) Gecko/20100101 Firefox/21.0" [21/Jun/2013:21:10:54 +0200] "GET /webmail/ HTTP/1.1" 302 475 "-" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:21.0) Gecko/20100101 Firefox/21.0"

  Read the article

• Rails program is not being run on apache + passenger - only directory listing

  - by user909943

  I have successfully installed Phusion passenger + Apache 2 + Rails 3.1 program + git on a linux Debian 6. I ran passenger-install-apache2-module and followed the configuration instructions. I followed also the setup instructions at https://help.ubuntu.com/community/RubyOnRails#Configure%20Apache My program is in /var/www/myrailsproject and runs fine on webrick on my mac. When going to myhomepage.com (example) I only see directory listing. By preventing directory listing and setting Options -Indexes in < Document tag in /etc/apache2/sites-available default or myhomepage.com I get an error on my website: Forbidden You don't have permission to access / on this server. Apache/2.2.19 (Debian) Server at myhomepage.com Port 80 In /etc/apache2/apache.conf I added: ServerName myhomepage.com LoadModule passenger_module /usr/lib/ruby/gems/1.8/gems/passenger-3.0.8/ext/apache2/mod_passenger.so PassengerRoot /usr/lib/ruby/gems/1.8/gems/passenger-3.0.8 PassengerRuby /usr/bin/ruby1.8 In /etc/apache2/sites-available myhomepage.com: < VirtualHost *:80 ServerName myhomepage.com ServerAlias www.myhomepage.com DocumentRoot /var/www/myrailsproject/public ErrorLog /var/www/logs/error.log CustomLog /var/www/logs/access.log combined RailsEnv test RackEnv test RailsBaseURI /mayrailsproject < Directory /var/www/myrailsproject> Options -Indexes FollowSymLinks -MultiViews AllowOverride all Order allow,deny allow from all < /Directory> < Directory /var/www/myrailsproject/public> AllowOverride All Options -Indexes +FollowSymLinks MultiViews Order allow,deny Allow from all < /Directory> RailsSpawnMethod smart PassengerPoolIdleTime 1000 RailsAppSpawnerIdleTime 0 RailsFrameworkSpawnerIdleTime 0 PassengerMaxRequests 5000 PassengerStatThrottleRate 5 < /VirtualHost I think I have tried all possible combinations of values and variables in < Directory (and < Directory /, < Directory /var/www etc.) the dafault looks like: < VirtualHost *:80 ServerName myhomepage.com RailsBaseURI /myrailsproject DocumentRoot /var/www/myrailsproject/public RackEnv test RailsEnv test < Directory /var/www/myrailsproject> Options -Indexes FollowSymLinks -MultiViews AllowOverride None Order deny,allow Deny from all < /Directory> <Directory /root/public/myrailsproject/public> Options -Indexes FollowSymLinks -MultiViews AllowOverride All Order allow,deny allow from all </Directory> ScriptAlias /cgi-bin/ /usr/lib/cgi-bin/ <Directory "/usr/lib/cgi-bin"> AllowOverride None Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch Order allow,deny Allow from all </Directory> ErrorLog ${APACHE_LOG_DIR}/error.log LogLevel warn CustomLog ${APACHE_LOG_DIR}/access.log combined Alias /doc/ "/usr/share/doc/" < Directory "/usr/share/doc/"> Options Indexes MultiViews FollowSymLinks AllowOverride None Order deny,allow Deny from all Allow from 127.0.0.0/255.0.0.0 ::1/128 < /Directory> < /VirtualHost So I wonder why my rails project is not being run, only directory listing. I do not have any index file in my project, routes.rb routes to root :to = 'static_pages#home' I think all permissions are as they should be. Thanks a lot in advance Regards Íris

  Read the article

• Custom ASP.Net MVC 2 ModelMetadataProvider for using custom view model attributes

  - by SeanMcAlinden

  There are a number of ways of implementing a pattern for using custom view model attributes, the following is similar to something I’m using at work which works pretty well. The classes I’m going to create are really simple: 1. Abstract base attribute 2. Custom ModelMetadata provider which will derive from the DataAnnotationsModelMetadataProvider   Base Attribute MetadataAttribute using System; using System.Web.Mvc; namespace Mvc2Templates.Attributes {     /// <summary>     /// Base class for custom MetadataAttributes.     /// </summary>     public abstract class MetadataAttribute : Attribute     {         /// <summary>         /// Method for processing custom attribute data.         /// </summary>         /// <param name="modelMetaData">A ModelMetaData instance.</param>         public abstract void Process(ModelMetadata modelMetaData);     } } As you can see, the class simple has one method – Process. Process accepts the ModelMetaData which will allow any derived custom attributes to set properties on the model meta data and add items to its AdditionalValues collection.   Custom Model Metadata Provider For a quick explanation of the Model Metadata and how it fits in to the MVC 2 framework, it is basically a set of properties that are usually set via attributes placed above properties on a view model, for example the ReadOnly and HiddenInput attributes. When EditorForModel, DisplayForModel or any of the other EditorFor/DisplayFor methods are called, the ModelMetadata information is used to determine how to display the properties. All of the information available within the model metadata is also available through ViewData.ModelMetadata. The following class derives from the DataAnnotationsModelMetadataProvider built into the mvc 2 framework. I’ve overridden the CreateMetadata method in order to process any custom attributes that may have been placed above a property in a view model.   CustomModelMetadataProvider using System; using System.Collections.Generic; using System.Linq; using System.Web.Mvc; using Mvc2Templates.Attributes; namespace Mvc2Templates.Providers {     public class CustomModelMetadataProvider : DataAnnotationsModelMetadataProvider     {         protected override ModelMetadata CreateMetadata(             IEnumerable<Attribute> attributes,             Type containerType,             Func<object> modelAccessor,             Type modelType,             string propertyName)         {             var modelMetadata = base.CreateMetadata(attributes, containerType, modelAccessor, modelType, propertyName);               attributes.OfType<MetadataAttribute>().ToList().ForEach(x => x.Process(modelMetadata));               return modelMetadata;         }     } } As you can see, once the model metadata is created through the base method, a check for any attributes deriving from our new abstract base attribute MetadataAttribute is made, the Process method is then called on any existing custom attributes with the model meta data for the property passed in.   Hooking it up The last thing you need to do to hook it up is set the new CustomModelMetadataProvider as the current ModelMetadataProvider, this is done within the Global.asax Application_Start method. Global.asax protected void Application_Start()         {             AreaRegistration.RegisterAllAreas();               RegisterRoutes(RouteTable.Routes);               ModelMetadataProviders.Current = new CustomModelMetadataProvider();         }   In my next post, I’m going to demonstrate a cool custom attribute that turns a textbox into an ajax driven AutoComplete text box. Hope this is useful. Kind Regards, Sean McAlinden.

  Read the article

• 5 reason why you should upgrade to new iPad (3rd generation)

  - by Gopinath

  Apple released the new iPad, 3rd generation, couple of days ago and they will be available in stores from March 16 onwards.  It’s the best tablet available in the market and for first time buyers it’s a no brainer to choose it. What about the iPad owners? Should they upgrade their iPad 2 to the new iPad? This is the question on the lips of most of the iPad owners. In this post we will provide you 5 reasons why you should upgrade your iPad, if more than two reasons are convincing then you should upgrade to the new iPad. Retina display – The best display ever made for mobile device, a game changer The new iPad comes with Retina display with screen resolution of 2048 x 1536, which is twice the resolution of iPad 2. Undoubtedly the iPad 3’s display is the best display ever made for a mobile device and it’s a game changer. With better resolution on iPad 3 eBook reading is going to be a pleasure with clear and crisp text Watching HD movies on iPad is going to be unbelievably good The new Games targeted for Retina display are going to be more realistic and needless to explain the pleasure of playing such games Graphic artists and photo editors get a professional on screen rendering support to create beautiful graphics 2x Faster & 2x Memory – Better Games and powerful Apps The new iPad is more powerful with 2x faster graphics and 2x more memory. Apple claims that the A5x processor of new iPad is 2x faster than iPad 2 and 4x faster than the best graphic chips available from other vendors. The RAM of  new iPad  is upgraded to 1 GB compared from 512 MB of iPad 2. With the fast processor and more memory, Apps and games are going to be blazing fast. 4G Internet – Browse the web at the speeds of 42 MB/sec Half of the iPad owners are frequent commuters who access internet over cellular networks, the new iPad’s 4G LTE is going to be a big boom for their  high data access needs. With the new iPad’s 4G LTE connectivity you can browse the web at 42 MB/sec and it mean you can watch a HD video without buffering issues. iPad 2 comes with 3G network support and it’s browsing speeds are way less than the new iPad. 5MP Camera – HD Movie Recording & gorgeous Photography iPad 2 has a 0.7 mega pixel camera and the new iPad comes with 5 megapixels camera. That is a huge boost for hobbyist  photographers and videographers. With the new iPad you can shoot gorgeous photos and 1080p HD video. The iSight camera of new iPad uses advanced optics with features like auto exposure, auto focus and face detection up to 10 faces. Amazon Pays up to $300 for old iPad 2 16 GB Wifi and more for other models Do you know that you can trade in your iPad 2 16 GB Wifi for upto $300? Amazon has an excellent trade in program for selling your used iPad 2s. Depending on the condition of the iPad 2  Amazon offers $234, $270, $300.00 for 16 GB Wifi versions that in Acceptable, Good and Like New conditions respectively.  The higher models of iPad 2s fetch you more money. With this great deal from Amazon the amount of extra money you need to spend for new iPad is almost half of their price. Visit Amazon Trade In’s website or read Amazon’s brilliant plan to pay you crazy money for your iPad 2 for more details. Related: New IPad Vs. IPad 2–Side By Side Comparison Of Hardware Specification [Infographic]

  Read the article

• Distinctly LINQ &ndash; Getting a Distinct List of Objects

  - by David Totzke

  Let’s say that you have a list of objects that contains duplicate items and you want to extract a subset of distinct items.  This is pretty straight forward in the trivial case where the duplicate objects are considered the same such as in the following example: List<int> ages = new List<int> { 21, 46, 46, 55, 17, 21, 55, 55 }; IEnumerable<int> distinctAges = ages.Distinct(); Console.WriteLine("Distinct ages:"); foreach (int age in distinctAges) { Console.WriteLine(age); } /* This code produces the following output: Distinct ages: 21 46 55 17 */ What if you are working with reference types instead?  Imagine a list of search results where items in the results, while unique in and of themselves, also point to a parent.  We’d like to be able to select a bunch of items in the list but then see only a distinct list of parents.  Distinct isn’t going to help us much on its own as all of the items are distinct already.  Perhaps we can create a class with just the information we are interested in like the Id and Name of the parents.  public class SelectedItem { public int ItemID { get; set; } public string DisplayName { get; set; } } We can then use LINQ to populate a list containing objects with just the information we are interested in and then get rid of the duplicates. IEnumerable<SelectedItem> list = (from item in ResultView.SelectedRows.OfType<Contract.ReceiptSelectResults>() select new SelectedItem { ItemID = item.ParentId, DisplayName = item.ParentName }) .Distinct(); Most of you will have guessed that this didn’t work.  Even though some of our objects are now duplicates, because we are working with reference types, it doesn’t matter that their properties are the same, they’re still considered unique.  What we need is a way to define equality for the Distinct() extension method. IEqualityComparer<T> Looking at the Distinct method we see that there is an overload that accepts an IEqualityComparer<T>.  We can simply create a class that implements this interface and that allows us to define equality for our SelectedItem class. public class SelectedItemComparer : IEqualityComparer<SelectedItem> { public new bool Equals(SelectedItem abc, SelectedItem def) { return abc.ItemID == def.ItemID && abc.DisplayName == def.DisplayName; } public int GetHashCode(SelectedItem obj) { string code = obj.DisplayName + obj.ItemID.ToString(); return code.GetHashCode(); } } In the Equals method we simply do whatever comparisons are necessary to determine equality and then return true or false.  Take note of the implementation of the GetHashCode method.  GetHashCode must return the same value for two different objects if our Equals method says they are equal.  Get this wrong and your comparer won’t work .  Even though the Equals method returns true, mismatched hash codes will cause the comparison to fail.  For our example, we simply build a string from the properties of the object and then call GetHashCode() on that. Now all we have to do is pass an instance of our IEqualitlyComarer<T> to Distinct and all will be well: IEnumerable<SelectedItem> list =     (from item in ResultView.SelectedRows.OfType<Contract.ReceiptSelectResults>()         select new SelectedItem { ItemID = item.dahfkp, DisplayName = item.document_code })                         .Distinct(new SelectedItemComparer());   Enjoy. Dave Just because I can… Technorati Tags: LINQ,C#

  Read the article

• ASP.NET MVC for the php/asp noob

  - by dotjosh

  I was talking to a friend today, who's foremost a php developer, about his thoughts on Umbraco and he said "Well they're apparently working feverishly on the new version of Umbraco, which will be MVC... which i still don't know what that means, but I know you like it." I ended up giving him a ground up explanation of ASP.NET MVC, so I'm posting this so he can link this to his friends and for anyone else who finds it useful.  The whole goal was to be as simple as possible, not being focused on proper syntax. Model-View-Controller (or MVC) is just a pattern that is used for handling UI interaction with your backend.  In a typical web app, you can imagine the *M*odel as your database model, the *V*iew as your HTML page, and the *C*ontroller as the class inbetween.  MVC handles your web request different than your typical php/asp app.In your php/asp app, your url maps directly to a php/asp file that contains html, mixed with database access code and redirects.In an MVC app, your url route is mapped to a method on a class (the controller).  The body of this method can do some database access and THEN decide which *V*iew (html/aspx page) should be displayed;  putting the controller in charge and not the view... a clear seperation of concerns that provides better reusibility and generally promotes cleaner code. Mysite.com, a quick example:Let's say you hit the following url in your application: http://www.mysite.com/Product/ShowItem?Id=4 To avoid tedious configuration, MVC uses a lot of conventions by default. For instance, the above url in your app would automatically make MVC search for a .net class with the name "Product" and a method named "ShowItem" based on the pattern of the url.  So if you name things properly, your method would automatically be called when you entered the above url.  Additionally, it would automatically map/hydrate the "int id" parameter that was in your querystring, matched by name.Product.cspublic class Product : Controller{    public ViewResult ShowItem(int id)    {        return View();    }} From this point you can write the code in the body of this method to do some database access and then pass a "bag" (also known as the ViewData) of data to your chosen *V*iew (html page) to use for display.  The view(html) ONLY needs to be worried about displaying the flattened data that it's been given in the best way it can;  this allows the view to be reused throughout your application as *just* a view, and not be coupled to HOW the data for that view get's loaded.. Product.cspublic class Product : Controller{    public ViewResult ShowItem(int id)    {        var database = new Database();        var item = database.GetItem(id);        ViewData["TheItem"] = item;        return View();    }} Again by convention, since the class' method name is "ShowItem", it'll search for a view named "ShowItem.aspx" by default, and pass the ViewData bag to it to use. ShowItem.aspx<html>     <body>      <%        var item =(Item)ViewData["TheItem"]       %>       <h1><%= item.FullProductName %></h1>     </body></html> BUT WAIT! WHY DOES MICROSOFT HAVE TO DO THINGS SO DIFFERENTLY!?They aren't... here are some other frameworks you may have heard of that use the same pattern in a their own way: Ruby On Rails Grails Spring MVC Struts Django    

  Read the article

• WCF RIA Services DomainContext Abstraction Strategies–Say That 10 Times!

  - by dwahlin

  The DomainContext available with WCF RIA Services provides a lot of functionality that can help track object state and handle making calls from a Silverlight client to a DomainService. One of the questions I get quite often in our Silverlight training classes (and see often in various forums and other areas) is how the DomainContext can be abstracted out of ViewModel classes when using the MVVM pattern in Silverlight applications. It’s not something that’s super obvious at first especially if you don’t work with delegates a lot, but it can definitely be done. There are various techniques and strategies that can be used but I thought I’d share some of the core techniques I find useful. To start, let’s assume you have the following ViewModel class (this is from my Silverlight Firestarter talk available to watch online here if you’re interested in getting started with WCF RIA Services): public class AdminViewModel : ViewModelBase { BookClubContext _Context = new BookClubContext(); public AdminViewModel() { if (!DesignerProperties.IsInDesignTool) { LoadBooks(); } } private void LoadBooks() { _Context.Load(_Context.GetBooksQuery(), LoadBooksCallback, null); } private void LoadBooksCallback(LoadOperation<Book> books) { Books = new ObservableCollection<Book>(books.Entities); } } Notice that BookClubContext is being used directly in the ViewModel class. There’s nothing wrong with that of course, but if other ViewModel objects need to load books then code would be duplicated across classes. Plus, the ViewModel has direct knowledge of how to load data and I like to make it more loosely-coupled. To do this I create what I call a “Service Agent” class. This class is responsible for getting data from the DomainService and returning it to a ViewModel. It only knows how to get and return data but doesn’t know how data should be stored and isn’t used with data binding operations. An example of a simple ServiceAgent class is shown next. Notice that I’m using the Action<T> delegate to handle callbacks from the ServiceAgent to the ViewModel object. Because LoadBooks accepts an Action<ObservableCollection<Book>>, the callback method in the ViewModel must accept ObservableCollection<Book> as a parameter. The callback is initiated by calling the Invoke method exposed by Action<T>: public class ServiceAgent { BookClubContext _Context = new BookClubContext(); public void LoadBooks(Action<ObservableCollection<Book>> callback) { _Context.Load(_Context.GetBooksQuery(), LoadBooksCallback, callback); } public void LoadBooksCallback(LoadOperation<Book> lo) { //Check for errors of course...keeping this brief var books = new ObservableCollection<Book>(lo.Entities); var action = (Action<ObservableCollection<Book>>)lo.UserState; action.Invoke(books); } } This can be simplified by taking advantage of lambda expressions. Notice that in the following code I don’t have a separate callback method and don’t have to worry about passing any user state or casting any user state (the user state is the 3rd parameter in the _Context.Load method call shown above). public class ServiceAgent { BookClubContext _Context = new BookClubContext(); public void LoadBooks(Action<ObservableCollection<Book>> callback) { _Context.Load(_Context.GetBooksQuery(), (lo) => { var books = new ObservableCollection<Book>(lo.Entities); callback.Invoke(books); }, null); } } A ViewModel class can then call into the ServiceAgent to retrieve books yet never know anything about the DomainContext object or even know how data is loaded behind the scenes: public class AdminViewModel : ViewModelBase { ServiceAgent _ServiceAgent = new ServiceAgent(); public AdminViewModel() { if (!DesignerProperties.IsInDesignTool) { LoadBooks(); } } private void LoadBooks() { _ServiceAgent.LoadBooks(LoadBooksCallback); } private void LoadBooksCallback(ObservableCollection<Book> books) { Books = books } } You could also handle the LoadBooksCallback method using a lambda if you wanted to minimize code just like I did earlier with the LoadBooks method in the ServiceAgent class.  If you’re into Dependency Injection (DI), you could create an interface for the ServiceAgent type, reference it in the ViewModel and then inject in the object to use at runtime. There are certainly other techniques and strategies that can be used, but the code shown here provides an introductory look at the topic that should help get you started abstracting the DomainContext out of your ViewModel classes when using WCF RIA Services in Silverlight applications.

  Read the article

• Adventures in MVVM &ndash; ViewModel Location and Creation

  - by Brian Genisio's House Of Bilz

  More Adventures in MVVM In this post, I am going to explore how I prefer to attach ViewModels to my Views.  I have published the code to my ViewModelSupport project on CodePlex in case you'd like to see how it works along with some examples.  Some History My approach to View-First ViewModel creation has evolved over time.  I have constructed ViewModels in code-behind.  I have instantiated ViewModels in the resources sectoin of the view. I have used Prism to resolve ViewModels via Dependency Injection. I have created attached properties that use Dependency Injection containers underneath.  Of all these approaches, I continue to find issues either in composability, blendability or maintainability.  Laurent Bugnion came up with a pretty good approach in MVVM Light Toolkit with his ViewModelLocator, but as John Papa points out, it has maintenance issues.  John paired up with Glen Block to make the ViewModelLocator more generic by using MEF to compose ViewModels.  It is a great approach, but I don’t like baking in specific resolution technologies into the ViewModelSupport project. I bring these people up, not to name drop, but to give them credit for the place I finally landed in my journey to resolve ViewModels.  I have come up with my own version of the ViewModelLocator that is both generic and container agnostic.  The solution is blendable, configurable and simple to use.  Use any resolution mechanism you want: MEF, Unity, Ninject, Activator.Create, Lookup Tables, new, whatever. How to use the locator 1. Create a class to contain your resolution configuration: public class YourViewModelResolver: IViewModelResolver { private YourFavoriteContainer container = new YourFavoriteContainer(); public YourViewModelResolver() { // Configure your container } public object Resolve(string viewModelName) { return container.Resolve(viewModelName); } } Examples of doing this are on CodePlex for MEF, Unity and Activator.CreateInstance. 2. Create your ViewModelLocator with your custom resolver in App.xaml: <VMS:ViewModelLocator x:Key="ViewModelLocator"> <VMS:ViewModelLocator.Resolver> <local:YourViewModelResolver /> </VMS:ViewModelLocator.Resolver> </VMS:ViewModelLocator> 3. Hook up your data context whenever you want a ViewModel (WPF): <Border DataContext="{Binding YourViewModelName, Source={StaticResource ViewModelLocator}}"> This example uses dynamic properties on the ViewModelLocator and passes the name to your resolver to figure out how to compose it. 4. What about Silverlight? Good question.  You can't bind to dynamic properties in Silverlight 4 (crossing my fingers for Silverlight 5), but you CAN use string indexing: <Border DataContext="{Binding [YourViewModelName], Source={StaticResource ViewModelLocator}}"> But, as John Papa points out in his article, there is a silly bug in Silverlight 4 (as of this writing) that will call into the indexer 6 times when it binds.  While this is little more than a nuisance when getting most properties, it can be much more of an issue when you are resolving ViewModels six times.  If this gets in your way, the solution (as pointed out by John), is to use an IndexConverter (instantiated in App.xaml and also included in the project): <Border DataContext="{Binding Source={StaticResource ViewModelLocator}, Converter={StaticResource IndexConverter}, ConverterParameter=YourViewModelName}"> It is a bit uglier than the WPF version (this method will also work in WPF if you prefer), but it is still not all that bad.  Conclusion This approach works really well (I suppose I am a bit biased).  It allows for composability from any mechanisim you choose.  It is blendable (consider serving up different objects in Design Mode if you wish... or different constructors… whatever makes sense to you).  It works in Cider.  It is configurable.  It is flexible.  It is the best way I have found to manage View-First ViewModel hookups.  Thanks to the guys mentioned in this article for getting me to something I love using.  Enjoy.

  Read the article

• Hidden exceptions

  - by user12617285

  Occasionally you may find yourself in a Java application environment where exceptions in your code are being caught by the application framework and either silently swallowed or converted into a generic exception. Either way, the potentially useful details of your original exception are inaccessible. Wouldn't it be nice if there was a VM option that showed the stack trace for every exception thrown, whether or not it's caught? In fact, HotSpot includes such an option: -XX:+TraceExceptions. However, this option is only available in a debug build of HotSpot (search globals.hpp for TraceExceptions). And based on a quick skim of the HotSpot source code, this option only prints the exception class and message. A more useful capability would be to have the complete stack trace printed as well as the code location catching the exception. This is what the various TraceException* options in in Maxine do (and more). That said, there is a way to achieve a limited version of the same thing with a stock standard JVM. It involves the use of the -Xbootclasspath/p non-standard option. The trick is to modify the source of java.lang.Exception by inserting the following: private static final boolean logging = System.getProperty("TraceExceptions") != null; private void log() { if (logging && sun.misc.VM.isBooted()) { printStackTrace(); } } Then every constructor simply needs to be modified to call log() just before returning: public Exception(String message) { super(message); log(); } public Exception(String message, Throwable cause) { super(message, cause); log(); } // etc... You now need to compile the modified Exception.java source and prepend the resulting class to the boot class path as well as add -DTraceExceptions to your java command line. Here's a console session showing these steps: % mkdir boot % javac -d boot Exception.java % java -DTraceExceptions -Xbootclasspath/p:boot -cp com.oracle.max.vm/bin test.output.HelloWorld java.util.zip.ZipException: error in opening zip file at java.util.zip.ZipFile.open(Native Method) at java.util.zip.ZipFile.(ZipFile.java:127) at java.util.jar.JarFile.(JarFile.java:135) at java.util.jar.JarFile.(JarFile.java:72) at sun.misc.URLClassPath$JarLoader.getJarFile(URLClassPath.java:646) at sun.misc.URLClassPath$JarLoader.access$600(URLClassPath.java:540) at sun.misc.URLClassPath$JarLoader$1.run(URLClassPath.java:607) at java.security.AccessController.doPrivileged(Native Method) at sun.misc.URLClassPath$JarLoader.ensureOpen(URLClassPath.java:599) at sun.misc.URLClassPath$JarLoader.(URLClassPath.java:583) at sun.misc.URLClassPath$3.run(URLClassPath.java:333) at java.security.AccessController.doPrivileged(Native Method) at sun.misc.URLClassPath.getLoader(URLClassPath.java:322) at sun.misc.URLClassPath.getLoader(URLClassPath.java:299) at sun.misc.URLClassPath.getResource(URLClassPath.java:168) at java.net.URLClassLoader$1.run(URLClassLoader.java:194) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:190) at sun.misc.Launcher$ExtClassLoader.findClass(Launcher.java:229) at java.lang.ClassLoader.loadClass(ClassLoader.java:306) at java.lang.ClassLoader.loadClass(ClassLoader.java:295) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301) at java.lang.ClassLoader.loadClass(ClassLoader.java:247) java.security.PrivilegedActionException at java.security.AccessController.doPrivileged(Native Method) at sun.misc.URLClassPath$JarLoader.ensureOpen(URLClassPath.java:599) at sun.misc.URLClassPath$JarLoader.(URLClassPath.java:583) at sun.misc.URLClassPath$3.run(URLClassPath.java:333) at java.security.AccessController.doPrivileged(Native Method) at sun.misc.URLClassPath.getLoader(URLClassPath.java:322) ... It's worth pointing out that this is not as useful as direct VM support for tracing exceptions. It has (at least) the following limitations: The trace is shown for every exception, whether it is thrown or not. It only applies to subclasses of java.lang.Exception as there appears to be bootstrap issues when the modification is applied to Throwable.java. It does not show you where the exception was caught. It involves overriding a class in rt.jar, something should never be done in a non-development environment.

  Read the article

• Speeding up procedural texture generation

  - by FalconNL

  Recently I've begun working on a game that takes place in a procedurally generated solar system. After a bit of a learning curve (having neither worked with Scala, OpenGL 2 ES or Libgdx before), I have a basic tech demo going where you spin around a single procedurally textured planet: The problem I'm running into is the performance of the texture generation. A quick overview of what I'm doing: a planet is a cube that has been deformed to a sphere. To each side, a n x n (e.g. 256 x 256) texture is applied, which are bundled in one 8n x n texture that is sent to the fragment shader. The last two spaces are not used, they're only there to make sure the width is a power of 2. The texture is currently generated on the CPU, using the updated 2012 version of the simplex noise algorithm linked to in the paper 'Simplex noise demystified'. The scene I'm using to test the algorithm contains two spheres: the planet and the background. Both use a greyscale texture consisting of six octaves of 3D simplex noise, so for example if we choose 128x128 as the texture size there are 128 x 128 x 6 x 2 x 6 = about 1.2 million calls to the noise function. The closest you will get to the planet is about what's shown in the screenshot and since the game's target resolution is 1280x720 that means I'd prefer to use 512x512 textures. Combine that with the fact the actual textures will of course be more complicated than basic noise (There will be a day and night texture, blended in the fragment shader based on sunlight, and a specular mask. I need noise for continents, terrain color variation, clouds, city lights, etc.) and we're looking at something like 512 x 512 x 6 x 3 x 15 = 70 million noise calls for the planet alone. In the final game, there will be activities when traveling between planets, so a wait of 5 or 10 seconds, possibly 20, would be acceptable since I can calculate the texture in the background while traveling, though obviously the faster the better. Getting back to our test scene, performance on my PC isn't too terrible, though still too slow considering the final result is going to be about 60 times worse: 128x128 : 0.1s 256x256 : 0.4s 512x512 : 1.7s This is after I moved all performance-critical code to Java, since trying to do so in Scala was a lot worse. Running this on my phone (a Samsung Galaxy S3), however, produces a more problematic result: 128x128 : 2s 256x256 : 7s 512x512 : 29s Already far too long, and that's not even factoring in the fact that it'll be minutes instead of seconds in the final version. Clearly something needs to be done. Personally, I see a few potential avenues, though I'm not particularly keen on any of them yet: Don't precalculate the textures, but let the fragment shader calculate everything. Probably not feasible, because at one point I had the background as a fullscreen quad with a pixel shader and I got about 1 fps on my phone. Use the GPU to render the texture once, store it and use the stored texture from then on. Upside: might be faster than doing it on the CPU since the GPU is supposed to be faster at floating point calculations. Downside: effects that cannot (easily) be expressed as functions of simplex noise (e.g. gas planet vortices, moon craters, etc.) are a lot more difficult to code in GLSL than in Scala/Java. Calculate a large amount of noise textures and ship them with the application. I'd like to avoid this if at all possible. Lower the resolution. Buys me a 4x performance gain, which isn't really enough plus I lose a lot of quality. Find a faster noise algorithm. If anyone has one I'm all ears, but simplex is already supposed to be faster than perlin. Adopt a pixel art style, allowing for lower resolution textures and fewer noise octaves. While I originally envisioned the game in this style, I've come to prefer the realistic approach. I'm doing something wrong and the performance should already be one or two orders of magnitude better. If this is the case, please let me know. If anyone has any suggestions, tips, workarounds, or other comments regarding this problem I'd love to hear them.

  Read the article

< Previous Page | 293 294 295 296 297 298 299 300 301 302 303 304  | Next Page >