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  • Why the databinding fails in ListView (WPF) ?

    - by Ashish Ashu
    I have a ListView of which ItemSource is set to my Custom Collection. I have defined a GridView CellTemplate that contains a combo box as below : <ListView MaxWidth="850" Grid.Row="1" SelectedItem="{Binding Path = SelectedCondition}" ItemsSource="{Binding Path = Conditions}" FontWeight="Normal" FontSize="11" Name="listview"> <ListView.View> <GridView> <GridViewColumn Width="175" Header="Type"> <GridViewColumn.CellTemplate> <DataTemplate> <ComboBox Style="{x:Null}" x:Name="TypeCmbox" Height="Auto" Width="150" SelectedValuePath="Key" DisplayMemberPath="Value" SelectedItem="{Binding Path = MyType}" ItemsSource="{Binding Path = MyTypes}" HorizontalAlignment="Center" /> </DataTemplate> </GridViewColumn.CellTemplate> </GridViewColumn> </ListView> My Custom collection is the ObservableCollection. I have a two buttons - Move Up and Move Down on top of the listview control . When user clicks on the Move Up or Move Down button I call MoveUp and MoveDown methods of Observable Collection. But when I Move Up and Move Down the rows then the Selected Index of a combo box is -1. I have ensured that selectedItem is not equal to null when performing Move Up and Move Down commands. Please Help!!

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  • Is there a case for parameterising using Abstract classes rather than Interfaces?

    - by Chris
    I'm currently developing a component based API that is heavily stateful. The top level components implement around a dozen interfaces each. The stock top-level components therefore sit ontop of a stack of Abstract implementations which in turn contain multiple mixin implementations and implement multiple mixin interfaces. So far, so good (I hope). The problem is that the base functionality is extremely complex to implement (1,000s of lines in 5 layers of base classes) and therefore I do not wish for component writers to implement the interfaces themselves but rather to extend my base classes (where all the boiler plate code is already written). If the API therefore accepts interfaces rather than references to the Abstract implementation that I wish for component writers to extends, then I have a risk that the implementer will not perform the validation that is both required and assumed by other areas of code. Therefore, my question is, is it sometimes valid to paramerise API methods using an abstract implementation reference rather than a reference to the interface(s) that it implements? Do you have an example of a well-designed API that uses this technique or am I trying to talk myself into bad-practice?

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  • How to model and handle presentation DTO's to abstract from complicated domain model?

    - by arrages
    Hi I am developing an application that needs to work with a complex domain model using Hibernate. This application uses Spring MVC and using the domain objects in the presentation layer is very messy so I think I should use DTO's that go to and from my service layer so that these match what I need in my views. Now lets assume I have a CarLease entity whose properties are not simple java primitives but it's composed with other entities like Make, Model, etc public class CarLease { private Make make; Private Model model; . . . } most properties are in this fashion and they are selectable using drop down selects on the jsp view, each will post back an ID to the controller. Now considering some standard use cases: create, edit, display How would you go about modeling the presentation DTO's to be used as form backing objects and communication between presentation and service layers?? Would you create a different DTO for each case (create, edit, display), would you make DTO's for the complex attributes? if so where would you translate the ID to entity? how and where would you handle validation, DTO/Domain assembly, what would you return from service layer methods? (create, edit, get) As you can see, I now I will benefit by separating my view from the domain objects (very complex with lots of stuff I don't need.) but I am having a hard time finding any real world examples and best practices for this. I need some architecture guidance from top to bottom, please keep in mind I will use Spring MVC in case that may leverage on your anwser. thanks in advance.

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  • Calling base Text method on custom TextBox

    - by The Demigeek
    I'm trying to create a CurrencyTextBox that inherits from TextBox. I'm seeing some really weird behavior that I just don't understand. After lots of testing, I think I can summarize as follows: In the class code, when I access base.Text (to get the textbox's text), I'm actually getting the return value of my overridden Text property. I thought the base keyword would ensure that the underlying object's methods get called. To demonstrate: public class cTestTextBox : System.Windows.Forms.TextBox { string strText = ""; public cTestTextBox() { SetVal("AAA"); base.Text = "TEST"; } public override string Text { get { string s = strText; s = "++" + s + "++"; return s; } } public void SetVal(string val) { strText = val; } } Place this control on a form and set a breakpoint on the constructor. Run the app. Hover your mouse over the base.Text expression. Note that the tooltip shows you the value of the overridden property, not the base property. Execute the SetVal() statement and again hover your mouse over the base.Text expression. Note that the tooltop shows you the value of the overridden property, not the base property. How do I reliably access the Text property of the textbox from which I'm inheriting?

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  • Confused about Android API's and compatability

    - by Keith
    I have purchased an HTC Incredible and have dived into the world of android! Only to find myself totally confused about the API levels and backward compatibility. My device runs the 2.1 OS, but I know that most of the devices out there run 1.5 or 1.6; and soon the 2.2 OS will be running on new devices. The SDK has gone through such enormous changes, that even constants have been renamed (from VIEW_ACTION to ACTION_VIEW for example). Methods have been added and removed (onPause replacing the earlier call, etc al). So, If I want to write an application that will work from 1.6+, does that mean I have to install and write my code using the 1.6 API; then test on later versions? Or can I write using the 2.1 SDK and just set the minSDK level and not use "new" features? I have never worked with an SDK that changes SO drastically from release to release! So I am not sure what to do.... I read through an article on the Android Development site(and this posting on stack overflow that references it: http://stackoverflow.com/questions/2076150/should-a-legacy-android-application-be-rebuilt-using-sdk-2-1), but it was still not very clear to me. Any help would be appreciated

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  • How to implement the API/SPI Pattern in Java?

    - by Adam Tannon
    I am creating a framework that exposes an API for developers to use: public interface MyAPI { public void doSomeStuff(); public int getWidgets(boolean hasRun); } All the developers should have to do is code their projects against these API methods. I also want them to be able to place different "drivers"/"API bindings" on the runtime classpath (the same way JDBC or SLF4J work) and have the API method calls (doSomeStuff(), etc.) operate on different 3rd party resources (files, servers, whatever). Thus the same code and API calls will map to operations on different resources depending on what driver/binding the runtime classpath sees (i.e. myapi-ftp, myapi-ssh, myapi-teleportation). How do I write (and package) an SPI that allows for such runtime binding, and then maps MyAPI calls to the correct (concrete) implementation? In other words, if myapi-ftp allows you to getWidgets(boolean) from an FTP server, how would I could this up (to make use of both the API and SPI)? Bonus points for concrete, working Java code example! Thanks in advance!

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  • How to use accessors within the same class in Objective C?

    - by Azeworai
    Hi, I have a few properties defined in my header file like so @property (assign) bool connectivity_N; @property (assign) bool isConnected_N; In my implementation file I have an init and the synthesized properties like so @implementation Map @synthesize connectivity_N; @synthesize isConnected_N; a init to set the initial values like so -(id) init { if( (self=[super init]) ) { //initialise default properties self.connectivity_N=NO; self.isConnected_N=NO; } return self; } I'm running into an error that states Error: accessing unknown 'connectivity_N' class method. In this public method within the class +(bool) isConnectable:(directions) theDirection{ bool isTheDirectionConnectable= NO; switch (theDirection) { case north: isTheDirectionConnectable= self.connectivity_N; break; I'm not sure why is this so as I'm trying to grab the value of the property. According to the apple developer documentation "The default names for the getter and setter methods associated with a property are propertyName and setPropertyName: respectively—for example, given a property “foo”, the accessors would be foo and setFoo:" That has given me a clue that I've done something wrong here, I'm fairly new to objective C so would appreciate anyone who spends the time to explain this to me. Thanks!

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  • NDK app onDestroy cleanup - how to DetachCurrentThread

    - by Aristarhys
    So if we attach we must detach thread after after it finish, right? JNIEnv* get_jni_env() { JNIEnv* res; JAVA_VM->GetEnv((void**) &res, JNI_VERSION_1_6);//Using cached JavaVM JAVA_VM->AttachCurrentThread(&res, NULL); return res; } I call next native method from @Override protected void onDestroy() of my Activity class void free_jni_manager() { JNIEnv* env = get_jni_env(); ... //Here i delete global refs (jclass) //JAVA_VM->DetachCurrentThread(); } ERROR: detaching thread with interp frames (count=16) - main thread still running and we try to detach it. Even if we take any function that use JNIEnv (for example calling java methods), putting DetachCurrentThread will cause same error. DetachCurrentThread works flawlessly if used in pthread function static void* thread_func(void* arg) { get_jni_env(); // attach new thread //Do thread stuff JAVA_VM->DetachCurrentThread();//thread done detached it with ok return NULL; } Do we need detach main thread then we done with JNI, there do it? Or then activity will be destroyed, it will freed itself with JavaVM? Do we need do call DestroyJavaVM() (just doing crash if use onDestroy), how free cached JavaVM or garbage cleaner will handle this? P.S. What benefits of using AttachCurrentThreadAsDaemon()

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  • Modal QMessageBox does not behave like native Windows dialogs

    - by Philip Daubmeier
    My application has a dialog that asks the user via a QMessageBox whether he wants to discard all changes he made or wants to keep editing. I want this dialog to be modal to the whole application. I read somewhere that this is the standard behavior for a QMessageBox, so I dont have to set it explicitly with something like: mbox.setWindowModality(Qt::ApplicationModal); I wonder why it behaves differently from other modal dialogs in the OS (Windows 7 in my case). On the one hand it functions like it should, i.e. all other input methods in the application are blocked until the user answeres the dialog. However, it doesn't 'blink'* if the user clicks any other window of the application. Is there any way to get Qt to behave like a native Windows dialog? Thanks in advance! *If you don't know what I mean with this 'blinking': Just open notepad on a Windows OS, type some text and try to close it. A dialog pops up that asks to save, discard or keep editing. Now click somewhere on the editor window - the border and titlebar of the dialog flashes/blinks a few times.

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  • Interesting Scala typing solution, doesn't work in 2.7.7?

    - by djc
    I'm trying to build some image algebra code that can work with images (basically a linear pixel buffer + dimensions) that have different types for the pixel. To get this to work, I've defined a parametrized Pixel trait with a few methods that should be able to get used with any Pixel subclass. (For now, I'm only interested in operations that work on the same Pixel type.) Here it is: trait Pixel[T <: Pixel[T]] { def mul(v: Double): T def max(v: T): T def div(v: Double): T def div(v: T): T } Now I define a single Pixel type that has storage based on three doubles (basically RGB 0.0-1.0), I've called it TripleDoublePixel: class TripleDoublePixel(v: Array[Double]) extends Pixel[TripleDoublePixel] { var data: Array[Double] = v def this() = this(Array(0.0, 0.0, 0.0)) def toString(): String = { "(" + data(0) + ", " + data(1) + ", " + data(2) + ")" } def increment(v: TripleDoublePixel) { data(0) += v.data(0) data(1) += v.data(1) data(2) += v.data(2) } def mul(v: Double): TripleDoublePixel = { new TripleDoublePixel(data.map(x => x * v)) } def div(v: Double): TripleDoublePixel = { new TripleDoublePixel(data.map(x => x / v)) } def div(v: TripleDoublePixel): TripleDoublePixel = { var tmp = new Array[Double](3) tmp(0) = data(0) / v.data(0) tmp(1) = data(1) / v.data(1) tmp(2) = data(2) / v.data(2) new TripleDoublePixel(tmp) } def max(v: TripleDoublePixel): TripleDoublePixel = { val lv = data(0) * data(0) + data(1) * data(1) + data(2) * data(2) val vv = v.data(0) * v.data(0) + v.data(1) * v.data(1) + v.data(2) * v.data(2) if (lv > vv) (this) else v } } Now I want to write code to use this, that doesn't have to know what type the pixels are. For example: def idiv[T](a: Image[T], b: Image[T]) { for (i <- 0 until a.data.size) { a.data(i) = a.data(i).div(b.data(i)) } } Unfortunately, this doesn't compile: (fragment of lindet-gen.scala):145: error: value div is not a member of T a.data(i) = a.data(i).div(b.data(i)) I was told in #scala that this worked for someone else, but that was on 2.8. I've tried to get 2.8-rc1 going, but it doesn't compile for me. Is there any way to get this to work in 2.7.7?

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  • lambda expressions in VB.NET... what am I doing wrong???

    - by Bob
    when I run this C# code, no problems... but when I translate it into VB.NET it compiles but blows due to 'CompareString' member not being allowed in the expression... I feel like I'm missing something key here... private void PrintButton_Click(object sender, EventArgs e) { if (ListsListBox.SelectedIndex > -1) { //Context using (ClientOM.ClientContext ctx = new ClientOM.ClientContext(UrlTextBox.Text)) { //Get selected list string listTitle = ListsListBox.SelectedItem.ToString(); ClientOM.Web site = ctx.Web; ctx.Load(site, s => s.Lists.Where(l => l.Title == listTitle)); ctx.ExecuteQuery(); ClientOM.List list = site.Lists[0]; //Get fields for this list ctx.Load(list, l => l.Fields.Where(f => f.Hidden == false && (f.CanBeDeleted == true || f.InternalName == "Title"))); ctx.ExecuteQuery(); //Get items for the list ClientOM.ListItemCollection listItems = list.GetItems( ClientOM.CamlQuery.CreateAllItemsQuery()); ctx.Load(listItems); ctx.ExecuteQuery(); // DOCUMENT CREATION CODE GOES HERE } MessageBox.Show("Document Created!"); } } but in VB.NET code this errors due to not being allowed 'CompareString' members in the ctx.Load() methods... Private Sub PrintButton_Click(sender As Object, e As EventArgs) If ListsListBox.SelectedIndex > -1 Then 'Context Using ctx As New ClientOM.ClientContext(UrlTextBox.Text) 'Get selected list Dim listTitle As String = ListsListBox.SelectedItem.ToString() Dim site As ClientOM.Web = ctx.Web ctx.Load(site, Function(s) s.Lists.Where(Function(l) l.Title = listTitle)) ctx.ExecuteQuery() Dim list As ClientOM.List = site.Lists(0) 'Get fields for this list ctx.Load(list, Function(l) l.Fields.Where(Function(f) f.Hidden = False AndAlso (f.CanBeDeleted = True OrElse f.InternalName = "Title"))) ctx.ExecuteQuery() 'Get items for the list Dim listItems As ClientOM.ListItemCollection = list.GetItems(ClientOM.CamlQuery.CreateAllItemsQuery()) ctx.Load(listItems) ' DOCUMENT CREATION CODE GOES HERE ctx.ExecuteQuery() End Using MessageBox.Show("Document Created!") End If End Sub

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  • C# WinForms populating TreeView from List<myObj>

    - by user743354
    I have this structure of classes: public class L3Message { public int Number { get; set; } public string MessageName { get; set; } public string Device { get; set; } public string Time { get; set; } public string ScramblingCode { get; set; } public List<Parameter> Parameters { get; set; } public L3Message() { Parameters = new List<Parameter>(); } } public class Parameter { public int numOfWhitespaces { get; set; } public string ParameterName { get; set; } public string ParameterValue { get; set; } public Parameter Parent { get; set; } public List<Parameter> SubParameters { get; set; } public Parameter() { SubParameters = new List<Parameter>(); } } So, as return type from one of my Methods I have List of L3Messages (List < L3Message ), and I need to map that to TreeView in WinForms (populate TreeView from that List). If possible, I would like to that in separate thread. How can I achieve that?

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  • Clarification/explanation of RegisterClientScriptInclude method

    - by mpminnich
    I've been looking on the Internet for a fairly clear explanation of the different methods of registering javascript in an asp.net application. I think I have a basic understating of the difference between registerStartupScript and registerClientScriptBlock (the main difference being where in the form the script is inserted). I'm not sure I understand what the RegisterClientScriptInclude method does or when it is used. From what I can gather, it is used to register an external .js file. Does this then make any and all javascript functions in that file available to the aspx page it was registered on? For example, if it was registered in the onLoad event of a master page, would all pages using that master page be able to use the javascript functions in the .js file? What problems would arise when trying to use document.getElementById in this case, if any? Also, when it is necessary/advantageous to use multiple .js files and register them separately? I appreciate any help you can give. If you know of any really good resources I can use to get a thorough understanding of this concept, I'd appreciate it!

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  • Implementations details of drag and drop of file path in cocoa.

    - by foo
    Hi, I'm trying to get a part of my window to react to drag and drop. In this case to copy the file path to the file being dropped on the view. I have looked over some documentation but I still have some problems to see exactly where I should implement my methods for drag and drop. I have seen some examples but almost all of them assumes that I want to drop an image on the view. I'm pretty new to cocoa and Xcode so, I have some problems with seeing the exact relation between interface builder and the generated code. I have created a subclass to NSView, called drop zone like this: #import <Cocoa/Cocoa.h> @interface dropZone : NSView { } @end I then use an NSRect to color it grey like this: #import "dropZone.h" @implementation dropZone - (void)drawRect:(NSRect)rect { NSRect bounds = [self bounds]; [[NSColor grayColor] set]; [NSBezierPath fillRect:bounds]; } @end I then drag this class to my window in interface builder. But I will need to implement the registerForDraggingTypes method, but where? I have also seen a convenience method in the Apple docs for file paths like this: dragFile:fromRect:slideBack:event: that might work.

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  • Unknown ListView Behavior

    - by st0le
    I'm currently making a SMS Application in Android, the following is a code snippet from Inbox Listactivity, I have requested a cursor from the contentresolver and used a custom adapter to add custom views into the list. Now, in the custom view i've got 2 TextViews (tvFullBody,*tvBody*)... tvFullBody contains the Full SMS Text while tvBody contains a short preview (35 characters) The tvFullBody Visibility is by default set to GONE. My idea is, when the user clicks on a list item, the tvBody should dissappear(GONE) and the tvFullBody should become visible (VISIBLE). On Clicking again, it should revert back to its original state. //isExpanded is a BitSet of the size = no of list items...keeps track of which items are expanded and which are not @Override protected void onListItemClick(ListView l, View v, int position, long id) { if(isExpanded.get(position)) { v.findViewById(R.id.tvFullBody).setVisibility(View.GONE); v.findViewById(R.id.tvBody).setVisibility(View.VISIBLE); }else { v.findViewById(R.id.tvFullBody).setVisibility(View.VISIBLE); v.findViewById(R.id.tvBody).setVisibility(View.GONE); } isExpanded.flip(position); super.onListItemClick(l, v, position, id); } The Code works as it is supposed to :) except for an undesired sideeffect.... Every 10th (or so) List Item also gets "toggled". eg. If i Expand the 1st, then the 11th, 21th list items are also expanded...Although they remain off screen, but on scrolling you get to see the undesired "expansion". By my novice analysis, i'm guessing Listview keeps track of 10 list items that are currently visible, upon scrolling, it "reuses" those same variables, which is causing this problem...(i didn't check the android source code yet.) I'd be gratefull for any suggestion, on how i should tackle this! :) I'm open to alternative methods aswell....Thanks in advance! :)

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  • Is there a faster way to access a property member of a class using reflection?

    - by Ross Goddard
    I am currently using the following code to access the property of an object using reflection: Dim propInfo As Reflection.PropertyInfo = myType.GetProperty(propName) Dim objValue As Object = propInfo.GetValue(myObject, Nothing) I am having some issues with the speed since this type of code is being called many times and is causing some slowdown. I have been looking into using Refelction.Emit or dynamic methods, but I am not sure exactly how to make use of them. Background Information: I am creating a list of a subset of the properties of the object, associating then with some meta information (such as if they can be loaded from the database or xml, if they are editable, can the user see them). This is for later consumption so we can write code such as : foreach prop as BaseWrapper in graphNode.NodeProperties prop.LoadFromDataRow(dr) next The application makes heavy use of having access to this list. The problem is that on the initial load of a project, a larger number of objects are being created that make use of this, so for each object created it is looping through this code a number of times. I initially tried adding each property to the list manually, but this ran into problems with not everything being initialized at the correct time and some other issues. If there is no other good way, then I may have to rethink some of the design and see what else can be done to improve the performance.

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  • Creating mock Objects in PHP unit

    - by Mike
    Hi, I've searched but can't quite find what I'm looking for and the manual isn't much help in this respect. I'm fairly new to unit testing, so not sure if I'm on the right track at all. Anyway, onto the question. I have a class: <?php class testClass { public function doSomething($array_of_stuff) { return AnotherClass::returnRandomElement($array_of_stuff); } } ?> Now, clearly I want the AnotherClass::returnRandomElement($array_of_stuff); to return the same thing every time. My question is, in my unit test, how do I mockup this object? I've tried adding the AnotherClass to the top of the test file, but when I want to test AnotherClass I get the "Cannot redeclare class" error. I think I understand factory classes, but I'm not sure how I would apply that in this instance. Would I need to write an entirely seperate AnotherClass class which contained test data and then use the Factory class to load that instead of the real AnotherClass? Or is using the Factory pattern just a red herring. I tried this: $RedirectUtils_stub = $this->getMockForAbstractClass('RedirectUtils'); $o1 = new stdClass(); $o1->id = 2; $o1->test_id = 2; $o1->weight = 60; $o1->data = "http://www.google.com/?ffdfd=fdfdfdfd?route=1"; $RedirectUtils_stub->expects($this->any()) ->method('chooseRandomRoot') ->will($this->returnValue($o1)); $RedirectUtils_stub->expects($this->any()) ->method('decodeQueryString') ->will($this->returnValue(array())); in the setUp() function, but these stubs are ignored and I can't work out whether it's something I'm doing wrong, or the way I'm accessing the AnotherClass methods. Help! This is driving me nuts.

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  • MVC JsonResult with the [Authorize] attribute going to Logon but not displaying the view

    - by likestoski
    I am seeing odd behavior with MVC 3 methods that return a JsonResult when used with the Authorize attribute. What looks like happens is the Authorize is correctly evaluated when I am not logged in but instead of redirecting to the logon form the Json response is the logon form. Is there an addition attribute that directs the response to not return a value but instead redirect the user to the logon form, preferebly with the correct returnUrl value? What I did as a demo was to setup a new MVC3 site and added AspNetMembership to my DB using the aspnet_regsql.exe command. All that is setup and logging me in correctly. The behavior of the JsonResult doesn't seem right and I'm hoping I have just missed an attribute to make it work properly. Any help is greatly appreciated, thanks in advance. Here is the Account Controller (leaving out the Post action which is not part of this question). public class AccountController : Controller { public ActionResult LogOn() { return View(); } [Authorize] public JsonResult AuthorizedAction() { return Json("Only returns if I am authorized"); } } Here is the Html markup: <script src="@Url.Content("~/Scripts/jquery-ui-1.8.11.min.js")" type="text/javascript"></script> <script type="text/javascript"> $(document).ready(function () { $("#btnTest").click(function () { $.ajax({ type: "POST", url: "Account/AuthorizedAction", data: {}, success: function (result) { $("#testMe").html(result); }, error: function (result) { $("#testMe").html('Something broke in the ajax request'); } }); }); }); </script> <input type="button" id="btnTest" value="Test me" /> <div id="testMe">I have initial text</div> The Result: 1) When logged in I get 'Only returns if I am authorized' in my test div 2) When not logged and I have a break point in my Logon() method I see this value Request["returnUrl"] "/Account/AuthorizedAction" The test div I have displays the logon form :) this seems like I'm just not handling this properly.

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  • java template design

    - by Sean Nguyen
    Hi, I have this class: public class Converter { private Logger logger = Logger.getLogger(Converter.class); public String convert(String s){ if (s == null) throw new IllegalArgumentException("input can't be null"); logger.debug("Input = " + s); String r = s + "abc"; logger.debug("Output = " + s); return r; } public Integer convert(Integer s){ if (s == null) throw new IllegalArgumentException("input can't be null"); logger.debug("Input = " + s); Integer r = s + 10; logger.debug("Output = " + s); return r; } } The above 2 methods are very similar so I want to create a template to do the similar things and delegate the actual work to the approriate class. But I also want to easily extends this frame work without changing the template. So for example: public class ConverterTemplate { private Logger logger = Logger.getLogger(Converter.class); public Object convert(Object s){ if (s == null) throw new IllegalArgumentException("input can't be null"); logger.debug("Input = " + s); Object r = doConverter(); logger.debug("Output = " + s); return r; } protected abstract Object doConverter(Object arg); } public class MyConverter extends ConverterTemplate { protected String doConverter(String str) { String r = str + "abc"; return r; } protected Integer doConverter(Integer arg) { Integer r = arg + 10; return r; } } But that doesn't work. Can anybody suggest me a better way to do that? I want to achieve 2 goals: 1. A template that is extensible and does all the similar work for me. 2. I ant to minimize the number of extended class. Thanks,

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  • Python: Calling method A from class A within class B?

    - by Tommo
    There are a number of questions that are similar to this, but none of the answers hits the spot - so please bear with me. I am trying my hardest to learn OOP using Python, but i keep running into errors (like this one) which just make me think this is all pointless and it would be easier to just use methods. Here is my code: class TheGUI(wx.Frame): def __init__(self, title, size): wx.Frame.__init__(self, None, 1, title, size=size) # The GUI is made ... textbox.TextCtrl(panel1, 1, pos=(67,7), size=(150, 20)) button1.Bind(wx.EVT_BUTTON, self.button1Click) self.Show(True) def button1Click(self, event): #It needs to do the LoadThread function! class WebParser: def LoadThread(self, thread_id): #It needs to get the contents of textbox! TheGUI = TheGUI("Text RPG", (500,500)) TheParser = WebParser TheApp.MainLoop() So the problem i am having is that the GUI class needs to use a function that is in the WebParser class, and the WebParser class needs to get text from a textbox that exists in the GUI class. I know i could do this by passing the objects around as parameters, but that seems utterly pointless, there must be a more logical way to do this that doesn't using classes seem so pointless? Thanks in advance!

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  • A question of long-running and disruptive branches

    - by Matt Enright
    We are about to begin prototyping a new application that will share some existing infrastructure assemblies with an existing application, and also involve a significant subset of the existing domain model. Parts of the domain model will likely undergo some serious changes for this new application, and the endgame for all of this, once the new application has been fully specified and is launch-ready is that we would like to re-unify the models of the two applications (as well as share a database, link functionality, etc.), but for the duration of development, prototyping, etc, we will be using a separate database so that we can change things without worrying about impact to development or use of the existing application. Since it is a prototype, there will be a pretty long window during which serious changes or rearchitecturing can occur as product management experiments with different workflows, different customer bases are surveyed, and we try and keep up. We have already made a Subversion branch, so as to not impact concurrent development on the mature application, and are toying with 2 potential ways of moving forward with this: Use the svn branch as the sole mechanism of separation. Make our changes to the existing domain models, and evaluate their impact on the existing application (and make requisite changes to ProjectA) when we have established that our long-running side branch is stable enough for re-entry to trunk. "Fork" the shared code (temporarily): Copy ProjectA.Entities to NewProject.Entities, and treat all of the NewProject code as self-contained. When all of the perturbations around the model have died down and we feel satisfied, manually re-integrate the changes (as granular or sweeping as warranted) back into ProjectA.Entities, updating ProjectA to use the improved models at each step (this can take place either before or after the subversion merge has occurred). The subversion merge will then not handle recombination of any of the heavy changes here. Note: the "fork" method only applies to the code we see significant changes in store for, and whose modification will break ProjectA - shared infrastructure stuff for example, we would just modify in place (on our branch) and let the merge sort out. Development is hard, go shopping. Naturally, after not coming to an agreement, we're turning it over to the oracle of power that is SO. Any experience with any of these methods, pain points to watch out for, something new entirely?

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  • Best Practices For Secure APIs?

    - by Ferrett Steinmetz
    Let's say I have a website that has a lot of information on our products. I'd like some of our customers (including us!) to be able to look up our products for various methods, including: 1) Pulling data from AJAX calls that return data in cool, JavaScripty-ways 2) Creating iPhone applications that use that data; 3) Having other web applications use that data for their own end. Normally, I'd just create an API and be done with it. However, this data is in fact mildly confidential - which is to say that we don't want our competitors to be able to look up all our products every morning and then automatically set their prices to undercut us. And we also want to be able to look at who might be abusing the system, so if someone's making ten million complex calls to our API a day and bogging down our server, we can cut them off. My next logical step would be then to create a developers' key to restrict access - which would work fine for web apps, but not so much for any AJAX calls. (As I see it, they'd need to provide the key in the JavaScript, which is in plaintext and easily seen, and hence there's actually no security at all. Particularly if we'd be using our own developers' keys on our site to make these AJAX calls.) So my question: after looking around at Oauth and OpenID for some time, I'm not sure there is a solution that would handle all three of the above. Is there some sort of canonical "best practices" for developers' keys, or can Oauth and OpenID handle AJAX calls easily in some fashion I have yet to grok, or am I missing something entirely?

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  • Best way to design a class in python

    - by Fraz
    So, this is more like a philosophical question for someone who is trying to understand classes. Most of time, how i use class is actually a very bad way to use it. I think of a lot of functions and after a time just indent the code and makes it a class and replacing few stuff with self.variable if a variable is repeated a lot. (I know its bad practise) But anyways... What i am asking is: class FooBar: def __init__(self,foo,bar): self._foo = foo self._bar = bar self.ans = self.__execute() def __execute(self): return something(self._foo, self._bar) Now there are many ways to do this: class FooBar: def __init__(self,foo): self._foo = foo def execute(self,bar): return something(self._foo, bar) Can you suggest which one is bad and which one is worse? or any other way to do this. This is just a toy example (offcourse). I mean, there is no need to have a class here if there is one function.. but lets say in __execute something() calls a whole set of other methods.. ?? Thanks

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  • How to implement iterator as an attribute of a class in Java

    - by de3
    Hi, let's say I have this simple MyArray class, with two simple methods: add, delete and an iterator. In the main method we can see how it is supposed to be used: public class MyArray { int start; int end; int[] arr; myIterator it; public MyArray(){ this.start=0; this.end=0; this.arr=new int[500]; it=new myIterator(); } public void add(int el){ this.arr[this.end]=el; this.end++; } public void delete(){ this.arr[this.start]=0; this.start++; } public static void main(String[] args){ MyArray m=new MyArray(); m.add(3); m.add(299); m.add(19); m.add(27); while(m.it.hasNext()){ System.out.println(m.it.next()); } } And then MyIterator should be implemented somehow: import java.util.Iterator; public class myIterator implements Iterator{ @Override public boolean hasNext() { // TODO Auto-generated method stub return false; } @Override public Object next() { // TODO Auto-generated method stub return null; } @Override public void remove() { // TODO Auto-generated method stub } } MyIterator should iterate arr from MyArray class, from start to end values; both are also attributes of MyArray. So, as MyIterator should use MyArray attributes, how should MyIterator be implemented? Perhaps I can send the current object in the initialization: it=new myIterator(this); But I guess it's not the best soultion. Or maybe MyArray itself should implement Iterator interface? How is this solved?

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  • Database/Object Mapping

    - by Eric
    Hello everyone, This is a beginner question, but it's been frustrating me... I am using C#, by the way. I'd like to make a few classes, each with their own properties and methods. I would also like to have a database to store certain instances of these classes in case I would ever need to look at them again. So, for example... class Polygon { String name; Double perimiter; int numSides; public Double GetArea() { // ... } } class Circle { String name; Double radius; public void PrintName() { // ... } } Say I've got these classes. I also want a database that has the TABLES "Polygon" and "Circle" with the COLUMNS "name" "perimeter" "radius" etc. And I want an easy way to save a class instance into the database, or pull a class instance out of the database. I have previously been using MS Access for my database stuff, which I don't mind using, but I would prefer if nothing other than .NET need to be installed. I've been researching online a bit, but I wanted to get some opinions on here. I have looked at Linq-to-Sql, but it seems you need Sql-Server. Is this true? If so, I'd really rather not use it because I don't want to have to have it installed everywhere. Anway, I'm just fishing for some ideas/insights/suggestions/etc. so please help me out if you can. Thanks.

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