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• How to Prevent PostBack Event Handler from Firing

  - by user331744

  I have a custom class (ServerSideValidator.vb) that validates user input on server side (it doesn't use any of the .NET built in validators, therefore Page.Validate() is not an option for me). I am calling the Validate() method on page.IsPostback event and the class performs without any problem My issue is, when validation fails (returns false), I want to stop the postback event handler from firing, but load the page along with all the controls and user-input values in them. If I do, Response.End(), the page comes up blank. I can programmatically instruct the page to go to the previous page (original form before postback), but it loses all user-inputs. I thought of creating a global boolean variable in the page code behind file and check the value before performing any postback method, but this approach takes away from my plan to provide all functionalities inside the class itself. The page object is being referenced to ServerSideValidator. Seems like all the postback related properties/variables I come across inside Page class are 'Readonly' and I can't assign value(s) to control/prevent postback event from firing. Any idiea on how I can accomplish this? Please let me know if you need further details

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• Pre Project Documentation

  - by DeanMc

  I have an issue that I feel many programmers can relate to... I have worked on many small scale projects. After my initial paper brain storm I tend to start coding. What I come up with is usually a rough working model of the actual application. I design in a disconnected fashion so I am talking about underlying code libraries, user interfaces are the last thing as the library usually dictates what is needed in the UI. As my projects get bigger I worry that so should my "spec" or design document. The above paragraph, from my investigations, is echoed all across the internet in one fashion or another. When a UI is concerned there is a bit more information but it is UI specific and does not relate to code libraries. What I am beginning to realise is that maybe code is code is code. It seems from my extensive research that there is no 1:1 mapping between a design document and the code. When I need to research a topic I dump information into OneNote and from there I prioritise features into versions and then into related chunks so that development runs in a fairly linear fashion, my tasks tend to look like so: Implement Binary File Reader Implement Binary File Writer Create Object to encapsulate Data for expression to the caller Now any programmer worth his salt is aware that between those three to do items could be a potential wall of code that could expand out to multiple files. I have tried to map the complete code process for each task but I simply don't think it can be done effectively. By the time one mangles pseudo code it is essentially code anyway so the time investment is negated. So my question is this: Am I right in assuming that the best documentation is the code itself. We are all in agreement that a high level overview is needed. How high should this be? Do you design to statement, class or concept level? What works for you?

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• In ArrayBlockingQueue, why copy final member field into local final variable?

  - by mjlee

  In ArrayBlockingQueue, any method that requires lock will get set 'final' local variable before calling 'lock()'. public boolean offer(E e) { if (e == null) throw new NullPointerException(); final ReentrantLock lock = this.lock; lock.lock(); try { if (count == items.length) return false; else { insert(e); return true; } } finally { lock.unlock(); } } Is there any reason to set a local variable 'lock' from 'this.lock' when field 'this.lock' is final also. Additionally, it also set local variable of E[] before acting on. private E extract() { final E[] items = this.items; E x = items[takeIndex]; items[takeIndex] = null; takeIndex = inc(takeIndex); --count; notFull.signal(); return x; } Is there any reason for copying to local final variable?

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• Java: Comparing a class with another within that class using a my own .equals

  - by user1670252

  I am making a method .equals replacing the equals method used. It accepts a object. I want it to check if that object equals the class that runs the .equals class. I know I want to compare all the private methods I have to that object. Is there a way to do this without making another private class to get the private variables from the object? How do I do this to compare equality not identity? I am stuck on this. Do i have to use == to compare? Also looking online i see others use recursion. If this is the way i have to do it can you show and explain it to me? so an example i have public boolean equals(Object o) { this is in a class we will call bobtheBuilder (first thing to pop in my head) I want to check if the object o is equal to the class he has private object array and a private int. I assume I want to check if the array and int of this class equal the array and int of the object.

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• Parsing CSS by regex

  - by Ross

  I'm creating a CSS editor and am trying to create a regular expression that can get data from a CSS document. This regex works if I have one property but I can't get it to work for all properties. I'm using preg/perl syntax in PHP. Regex (?<selector>[A-Za-z]+[\s]*)[\s]*{[\s]*((?<properties>[A-Za-z0-9-_]+)[\s]*:[\s]*(?<values>[A-Za-z0-9#, ]+);[\s]*)*[\s]*} Test case body { background: #f00; font: 12px Arial; } Expected Outcome Array( [0] => Array( [0] => body { background: #f00; font: 12px Arial; } [selector] => Array( [0] => body ) [1] => Array( [0] => body ) [2] => font: 12px Arial; [properties] => Array( [0] => font ) [3] => Array( [0] => font ) [values] => Array( [0] => 12px Arial [1] => background: #f00 ) [4] => Array( [0] => 12px Arial [1] => background: #f00 ) ) ) Real Outcome Array( [0] => Array ( [0] => body { background: #f00; font: 12px Arial; } [selector] => body [1] => body [2] => font: 12px Arial; [properties] => font [3] => font [values] => 12px Arial [4] => 12px Arial ) ) Thanks in advance for any help - this has been confusing me all afternoon!

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• query sql database for specific value in vb.net

  - by user2952298

  I am trying to convert VBA code to vb.net, im having trouble trying to search the database for a specific value around an if statement. any suggestions would be greatly appriciated. thedatabase is called confirmation, type is the column and email is the value im looking for. could datasets work? Function SendEmails() As Boolean Dim objOutlook As Outlook.Application Dim objOutlookMsg As Outlook.MailItem Dim objOutlookRecip As Outlook.Recipient Dim objOutlookAttach As Outlook.Attachment Dim intResponse As Integer Dim confirmation As New ADODB.Recordset Dim details As New ADODB.Recordset On Error GoTo Err_Execute Dim MyConnObj As New ADODB.Connection Dim cn As New ADODB.Connection() MyConnObj.Open( _ "Provider = sqloledb;" & _ "Server=myserver;" & _ "Database=Email_Text;" & _ "User Id=bla;" & _ "Password=bla;") confirmation.Open("Confirmation_list", MyConnObj) details.Open("MessagesToSend", MyConnObj) If details.EOF = False Then confirmation.MoveFirst() Do While Not confirmation.EOF If confirmation![Type] = "Email" Then ' Create the Outlook session. objOutlook = CreateObject("Outlook.Application") ' Create the message. End IF

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• check if two subsets of integers are equal using equals method

  - by MAS

  I have this java method in class called IntArray. The class has methods to add integers to a set or remove integers from a set,check size of a set, and check if 2 sets are equal. the 2 sets are created using 2 different objects of type IntArray in main, lets say object A and B. equals method supposed to check if two sets of integers are equal. for example set A = {1,2,3} and B = {1,2,3,4}. The method still return true even though one set is a subset of the other set. What exactly I am doing wrong? Thanks. //part of the code in main IntArray A = new IntArray(); IntArray B = new IntArray(); if(A.equals(B)) System.out.println("A and B are equal"); //equals method in IntArray class public boolean equals(Object b) { if (b instanceof IntArray) { IntArray A = (IntArray) b; for (int i = 0; i < data.length; i++) if (countOccurrences(data[i]) != A.countOccurrences(data[i])) return false; return true; } else return false; }

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• [Rails] checkbox to update attribute

  - by Jeff

  [Updated a bit] I have a Task model that has a :completed boolean attribute. If I click on it I want it to execute the 'finish' method. The main problem is that I am displays a series of checkboxes in a list and subsequent checkboxes after the first one are ignored. The method is never called for the given task/checkbox combo. I have this chunk of code in my view: <% current_user.tasks.each do |t|%> <% if t.completed == false %> <%= check_box_tag :completed, true, checked = false %> <%= observe_field :completed, :url => { :controller => 'tasks', :action => :finish , :id => t.id }, :frequency => 0.25, :update => :completed, :with => true %> and my finish method looks like this: def finish @task = Task.find(params[:id]) new = {:completed => true} @task.update_attributes(new) render :update do |page| page.replace_html "taskListing", :partial => 'home/task_listing' end

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• Indirect property notification

  - by Carlo

  Hello, this question might look a little trivial, but it might not be. I'm just wondering which of the following two cases is better for indirect property notification, or perhaps there is an even better way. The scenario: I have two properties, the first one is an object called HoldingObject, the second one is a boolean called IsHoldingObject, which is false if HoldingObject == null, otherwise it's true. I'm just wondering what is the best notification mechanism for IsHoldingObject: Case (A) - Notify IsHoldingObject changed from the HoldingObject proeperty: public class NotifyingClass1 : INotifyPropertyChanged { private object _holdingObject; public object HoldingObject { get { return _holdingObject; } set { if (_holdingObject != value) { _holdingObject = value; NotifyPropertyChanged("HoldingObject"); // Notify from the property that is being checked NotifyPropertyChanged("IsHoldingObject"); } } } public bool IsHoldingObject { get { return this.HoldingObject == null; } } #region INotifyPropertyChanged Members public event PropertyChangedEventHandler PropertyChanged; private void NotifyPropertyChanged(string propertyName) { if (this.PropertyChanged != null) this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName)); } #endregion } Case (B) - Notify IsHoldingObject changed from the IsHoldingObject directly, by setting it to false or true from HoldingObject property: public class NotifyingClass2 : INotifyPropertyChanged { private object _holdingObject; public object HoldingObject { get { return _holdingObject; } set { if (_holdingObject != value) { _holdingObject = value; NotifyPropertyChanged("HoldingObject"); // 1) Set the property here this.IsHoldingObject = _holdingObject != null; } } } private bool _isHoldingObject; public bool IsHoldingObject { get { return _isHoldingObject; } set { if (_isHoldingObject != value) { _isHoldingObject = value; // 2) Notify directly from the property NotifyPropertyChanged("IsHoldingObject"); } } } #region INotifyPropertyChanged Members public event PropertyChangedEventHandler PropertyChanged; private void NotifyPropertyChanged(string propertyName) { if (this.PropertyChanged != null) this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName)); } #endregion } I personally lean to the first one because it requires less code, but I'm not sure how recommendable it is to do that. Let me know if there is another (better) way. Thanks!

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• CAML query returns wrong results?

  - by Abe Miessler

  I have the following code: SPQuery oQuery = new SPQuery(); oQuery.Query = @"<Query> <Where> <And> <Eq> <FieldRef Name='PublishToSM' /> <Value Type='Boolean'>1</Value> </Eq> <IsNull> <FieldRef Name='SMUpdateDate' /> </IsNull> </And> </Where> </Query>"; SPListItemCollection collListItems = list.GetItems(oQuery); NevCoSocialMedia.NevCoFacebook fb = new NevCoSocialMedia.NevCoFacebook(); foreach (SPListItem oListItem in collListItems) { if (oListItem.Fields.ContainsField("PublishToSM") && Convert.ToBoolean(oListItem["PublishToSM"]) == true) { . . . My question is why do I need to have the last if statement? If I don't have this it will throw an error saying that the identifier does not exist when it tries to do oListItem["PublishToSM"]. This seems impossible since my CAML query is checking that that has an appropriate value...

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• In ActionScript, is there a way to test for existence of variable with datatype "Function"

  - by Robusto

  So I have a class where I instantiate a variable callback like so: public var callback:Function; So far so good. Now, I want to add an event listener to this class and test for existence of the callback. I'm doing like so: this.addEventListener(MouseEvent.MOUSE_OVER, function(event:MouseEvent) : void { if (callback) { // do some things } }); This works great, doesn't throw any errors, but everywhere I test for callback I get the following warning: 3553: Function value used where type Boolean was expected. Possibly the parentheses () are missing after this function reference. That bugged me, so I tried to get rid of the warning by testing for null and undefined. Those caused errors. I can't instantiate a Function as null, either. I know, I know, real programmers only care about errors, not warnings. I will survive if this situation is not resolved. But it bothers me! :) Am I just being neurotic, or is there actually some way to test whether a real Function has been created without the IDE bitching about it?

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• How do I use the Enum value from a class in another part of code?

  - by ChiggenWingz

  Coming from a C# background from a night course at a local college, I've sort of started my way in C++. Having a lot pain getting use to the syntax. I'm also still very green when it comes to coding techniques. From my WinMain function, I want to be able to access a variable which is using an enum I declared in another class. (inside core.h) class Core { public: enum GAME_MODE { INIT, MENUS, GAMEPLAY }; GAME_MODE gameMode; Core(); ~Core(); ...OtherFunctions(); }; (inside main.cpp) Core core; int WINAPI WinMain(...) { ... startup code here... core.gameMode = Core.GAME_MODE.INIT; ...etc... } Basically I want to set that gameMode to the enum value of Init or something like that from my WinMain function. I want to also be able to read it from other areas. I get the error... expected primary-expression before '.' token If I try to use core.gameMode = Core::GAME_MODE.INIT;, then I get the same error. I'm not fussed about best practices, as I'm just trying to get the basic understanding of passing around variables in C++ between files. I'll be making sure variables are protected and neatly tucked away later on once I am use to the flexibility of the syntax. If I remember correctly, C# allowed me to use Enums from other classes, and all I had to do was something like Core.ENUMNAME.ENUMVALUE. I hope what I'm wanting to do is clear :\ As I have no idea what a lot of the correct terminology is.

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• problem linking vba modules in MS Access 2007

  - by Ted

  I am upgrading a database system from Access 2000 db to Access 2007, which communicates with several chemistry measuring devices(pH meter, scale, etc) via an RS 232 serial port. The first db consists of several modules containing vba code that enables the communications with the ports, as well as supports the code behind the forms in the second db. The user, or lab tech, navigates through the forms in the second db to interact with the lab devices, and also to generate the reports which display the info. from the devices. The reports are also part of the second db. The code works in Access 2000, but once I convert it to 2007, the code in the second db cannot find the function calls in the first db that dictate the progression from screen to screen. I have tried importing the modules into the second db, and I have tried linking them, but it still doesn't work. The error message is #438: "Object doesn't support this property or method." Any suggestions would be greatly appreciated. Here is the code for the first function that is not being called correctly: Description: ' This routine is used to return to the calling form and close the active form. ' ' Input: ' strFormCalled --- the active form ' strCallingForm --- the form that called the active form ' blnUnhideOrOpen --- whether to open or just unhide form Public Sub basReturnToCallingForm(ByVal strFormCalled As String, ByVal _ strCallingForm As Variant, Optional blnUnhideOrOpen As Boolean = True) On Error GoTo err_basReturnToCaliingForm If Not basIsBlankString(strCallingForm) And blnUnhideOrOpen Then DoCmd.OpenForm strCallingForm, acNormal Else Call basUnHideForm(strCallingForm) End If Call basCloseForm(strFormCalled) exit_basReturnToCaliingForm: Exit Sub err_basReturnToCaliingForm: Err.Raise Err.Number, "basReturnToCaliingForm", Err.Description End Sub I will post the second function shortly, but I have to go to a meeting... The second funtion that isn't 'working' is a cmdStartClick that is supposed to be called when a user initializes a pump. However, within that function, it's also sticking on a line that is supposed to progress to the next form in the db. The other thing is that the code works in Access 2002, but not in Access 2007...

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• TreeView update bug in the VB.NET

  - by CFP

  Consider the following code: Dim Working As Boolean = False Private Sub TreeView1_AfterCheck(ByVal sender As Object, ByVal e As System.Windows.Forms.TreeViewEventArgs) Handles TreeView1.AfterCheck If Working Then Exit Sub Working = True e.Node.Checked = Not e.Node.Checked Working = False End Sub Private Sub TreeView1_MouseClick(ByVal sender As System.Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles TreeView1.MouseClick If e.Button = Windows.Forms.MouseButtons.Right Then MsgBox("Checked = " & TreeView1.SelectedNode.Checked) End Sub Where TreeView1 is a TreeView added to the form, with CheckBoxes set to true and one node added. The code basically cancel any node checking occuring on the form. Single-clicking the top node to check it works well : your click is immediately canceled. Yet if you double-click the checkbox, it will display a tick. But verifying the check state through a right click will yield a Checked = False dialog. How come? Is it a bug (I'm using the latest .Net Framework 4.0, and he same occurs in 2.0), or am I doing something wrong here? Is there a work around? Thanks! EDIT: Additionally, the MouseDoubleClick event is not raised before you click once again. EDIT 2: Posted a bug report at Microsoft Connect

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• Dynamic Select boxes page load

  - by Chris

  Hello, I have a dynamic chained select box that I am attempting to show the value of on a page load. In my chained select box, it will default to the first option within the select box on page load, could anyone provide assitance? I stumbled upon this thread, but I can't seem to translate what they are doing with that answer to my language of CF. Dynamic chained drop downs on page refresh Here is the JS script I am using. function dynamicSelect(id1, id2) { // Feature test to see if there is enough W3C DOM support if (document.getElementById && document.getElementsByTagName) { // Obtain references to both select boxes var sel1 = document.getElementById(id1); var sel2 = document.getElementById(id2); // Clone the dynamic select box var clone = sel2.cloneNode(true); // Obtain references to all cloned options var clonedOptions = clone.getElementsByTagName("option"); // Onload init: call a generic function to display the related options in the dynamic select box refreshDynamicSelectOptions(sel1, sel2, clonedOptions); // Onchange of the main select box: call a generic function to display the related options in the dynamic select box sel1.onchange = function() { refreshDynamicSelectOptions(sel1, sel2, clonedOptions); } } } function refreshDynamicSelectOptions(sel1, sel2, clonedOptions) { // Delete all options of the dynamic select box while (sel2.options.length) { sel2.remove(0); } // Create regular expression objects for "select" and the value of the selected option of the main select box as class names var pattern1 = /( |^)(select)( |$)/; var pattern2 = new RegExp("( |^)(" + sel1.options[sel1.selectedIndex].value + ")( |$)"); // Iterate through all cloned options for (var i = 0; i < clonedOptions.length; i++) { // If the classname of a cloned option either equals "select" or equals the value of the selected option of the main select box if (clonedOptions[i].className.match(pattern1) || clonedOptions[i].className.match(pattern2)) { // Clone the option from the hidden option pool and append it to the dynamic select box sel2.appendChild(clonedOptions[i].cloneNode(true)); } } } Thanks so much for any assistance

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• File mkdirs() method not working in android/java

  - by Leif Andersen

  I've been pulling out my hair on this for a while now. The following method is supposed to download a file, and save it to the location specified on the hard drive. private static void saveImage(Context context, boolean backgroundUpdate, URL url, File file) { if (!Tools.checkNetworkState(context, backgroundUpdate)) return; // Get the image try { // Make the file file.getParentFile().mkdirs(); // Set up the connection URLConnection uCon = url.openConnection(); InputStream is = uCon.getInputStream(); BufferedInputStream bis = new BufferedInputStream(is); // Download the data ByteArrayBuffer baf = new ByteArrayBuffer(50); int current = 0; while ((current = bis.read()) != -1) { baf.append((byte) current); } // Write the bits to the file OutputStream os = new FileOutputStream(file); os.write(baf.toByteArray()); os.close(); } catch (Exception e) { // Any exception is probably a newtork faiilure, bail return; } } Also, if the file doesn't exist, it is supposed to make the directory for the file. (And if there is another file already in that spot, it should just not do anything). However, for some reason, the mkdirs() method never makes the directory. I've tried everything from explicit parentheses, to explicitly making the parent file class, and nothing seems to work. I'm fairly certain that the drive is writable, as it's only called after that has already been determined, also that is true after running through it while debugging. So the method fails because the parent directories aren't made. Can anyone tell me if there is anything wrong with the way I'm calling it? Also, if it helps, here is the source for the file I'm calling it in: https://github.com/LeifAndersen/NetCatch/blob/master/src/net/leifandersen/mobile/android/netcatch/services/RSSService.java Thank you

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• AudioRecord - empty buffer

  - by Arxas

  I' m trying to record some audio using AudioRecord class. Here is my code: int audioSource = AudioSource.MIC; int sampleRateInHz = 44100; int channelConfig = AudioFormat.CHANNEL_IN_MONO; int audioFormat = AudioFormat.ENCODING_PCM_16BIT; int bufferSizeInShorts = 44100; int bufferSizeInBytes = 2*bufferSizeInShorts; short Data[] = new short[bufferSizeInShorts]; Thread recordingThread; AudioRecord audioRecorder = new AudioRecord(audioSource, sampleRateInHz, channelConfig, audioFormat, bufferSizeInBytes); @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } @Override public boolean onCreateOptionsMenu(Menu menu) { getMenuInflater().inflate(R.menu.activity_main, menu); return true; } public void startRecording(View arg0) { audioRecorder.startRecording(); recordingThread = new Thread(new Runnable() { public void run() { while (Data[bufferSizeInShorts-1] == 0) audioRecorder.read(Data, 0, bufferSizeInShorts); } }); audioRecorder.stop(); } Unfortunately my short array is empty after the recording is over. May I kindly ask you to help me figure out what's wrong?

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• Removing Item from Collection / Changing field of Object

  - by x Nuclear 213

  public void searchOwner(List<Appointments> appts, String owner) { Appointments theOne = null; for (Appointments temp : appts) { if (owner.equalsIgnoreCase(temp.owner.name)) { System.out.println(temp.data); temp.setResolved(true); } } } public void checkRemoval() { for (Appointments appts : appointments) { if (appts.resolved == true) { appointments.remove(appts); } //Iterator method used before enhanced for-loop public void checkRemovalI(){ Iterator<Appointments> it = appointments.iterator(); while(it.hasNext()){ if(it.next().resolved = true){ it.remove(); } } } So far this is where I am encountering my problem. I am trying to check the arrayList of Appointments and see if the field (resolved) is set to true, however I am receiving an ConcurrentModification exception during the searchOwner method when trying to set resolved = to true. I've tried using an Iterator in checkRemoval instead of an enhanced for-loop however that didn't help either. I really only need to get the part where the appointment is set to true to work, the checkRemoval seemed to be working early before implementing the changing of the boolean resolved. Any help will be greatly appreciated, thank you.

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• [VB.Net] TreeView update bug in the .net framework

  - by CFP

  Consider the following code: Dim Working As Boolean = False Private Sub TreeView1_AfterCheck(ByVal sender As Object, ByVal e As System.Windows.Forms.TreeViewEventArgs) Handles TreeView1.AfterCheck If Working Then Exit Sub Working = True e.Node.Checked = Not e.Node.Checked Working = False End Sub Private Sub TreeView1_MouseClick(ByVal sender As System.Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles TreeView1.MouseClick If e.Button = Windows.Forms.MouseButtons.Right Then MsgBox("Checked = " & TreeView1.SelectedNode.Checked) End Sub Where TreeView1 is a TreeView added to the form, with CheckBoxes set to true and one node added. The code basically cancel any node checking occuring on the form. Single-clicking the top node to check it works well : your click is immediately canceled. Yet if you double-click the checkbox, it will display a tick. But verifying the check state through a right click will yield a Checked = False dialog. How come? Is it a bug (I'm using the latest .Net Framework 4.0, and he same occurs in 2.0), or am I doing something wrong here? Is there a work around? Thanks! EDIT: Additionally, the MouseDoubleClick event is not raised before you click once again.

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• Find window with specific text for a Process

  - by Axarydax

  Hello, I'm trying to find if a window with specific has been open by a Process. That process spawns multiple windows, and I need to check them all. I have no trouble finding the process, with foreach (Process p in Process.GetProcesses()) { if (p.MainModule.FileName.ToLower().EndsWith("foo.exe")) FindChildWindowWithText(p); //do work the problem is what to do next. I cannot use Process' MainWindowText, because it changes with whichever window is activated. Then I've tried to use Windows function EnumChildWindows and GetWindowText, but I am not sure if I'm passing a correct handle to EnumChildWindows. The EnumChildWindows works as expected when passed MainWindowHandle, but of course the MainWindowHandle changes with active window. So I passed Process.Handle, but I get different handles and different results when switching the app's windows. (I understand that EnumChildWindows returns handles to not only windows, but controls in .net speak, that's no problem if I could get the caption of the window too) Maybe I am doing this the wrong way and I need a different approach - again, my problem is as simple as finding a window with text that matches specific regular expression. So I would probably need a function that enumerates all windows, that are visible in the taskbar or so. Thanks

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• Speed comparison - Template specialization vs. Virtual Function vs. If-Statement

  - by Person

  Just to get it out of the way... Premature optimization is the root of all evil Make use of OOP etc. I understand. Just looking for some advice regarding the speed of certain operations that I can store in my grey matter for future reference. Say you have an Animation class. An animation can be looped (plays over and over) or not looped (plays once), it may have unique frame times or not, etc. Let's say there are 3 of these "either or" attributes. Note that any method of the Animation class will at most check for one of these (i.e. this isn't a case of a giant branch of if-elseif). Here are some options. 1) Give it boolean members for the attributes given above, and use an if statement to check against them when playing the animation to perform the appropriate action. Problem: Conditional checked every single time the animation is played. 2) Make a base animation class, and derive other animations classes such as LoopedAnimation and AnimationUniqueFrames, etc. Problem: Vtable check upon every call to play the animation given that you have something like a vector<Animation>. Also, making a separate class for all of the possible combinations seems code bloaty. 3) Use template specialization, and specialize those functions that depend on those attributes. Like template<bool looped, bool uniqueFrameTimes> class Animation. Problem: The problem with this is that you couldn't just have a vector<Animation> for something's animations. Could also be bloaty. I'm wondering what kind of speed each of these options offer? I'm particularly interested in the 1st and 2nd option because the 3rd doesn't allow one to iterate through a general container of Animations. In short, what is faster - a vtable fetch or a conditional?

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• When to define SDD operations System->Actor?

  - by devoured elysium

  I am having some trouble understanding how to make SDDs, as I don't fully grasp why in some cases one should define operations for System - Actor and in others don't. Here is an example: 1) The User tells the System that wants to buy some tickets, stating his client number. 2) The System confirms that the given client number is valid. 3) The User tells the System the movie that wants to see. 4) The System shows the set of available sessions and seats for that movie. 5) The System asks the user which session/seat he wants. 6) The user tells the System the chosen session/seat. This would be converted to: a) -----> tellClientNumber(clientNumber) b) <----- validClientNumber c) -----> tellMovieToSee(movie) d) <----- showsAvailableSeatsHours e) -----> tellSystemChosenSessionSeat(session, seat) I know that when we are dealing with SDD's we are still far away from coding. But I can't help trying to imagine how it how it would have been had I to convert it right away to code: I can understand 1) and 2). It's like if it was a C#/Java method with the following signature: boolean tellClientNumber(clientNumber) so I put both on the SDD. Then, we have the pair 3) 4). I can imagine that as something as: SomeDataStructureThatHoldsAvailableSessionsSeats tellSystemMovieToSee(movie) Now, the problem: From what I've come to understand, my lecturer says that we shouldn't make an operation on the SDD for 5) as we should only show operations from the Actor to the System and when the System is either presenting us data (as in c)) or validating sent data (such as in b)). I find this odd, as if I try to imagine this like a DOS app where you have to put your input sequencially, it makes sense to make an arrow even for 5). Why is this wrong? How should I try to visualize this? Thanks

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• Save as Ringtone from ContextMenu

  - by kostas_menu

  I have created a button that onClick plays a mp3 file.I have also create a context menu that when you press the button for 2 secs it prompts you to save it as ringtone.How can i save it somewhere in my sd?this is my code: public void onCreate(Bundle icicle) { super.onCreate(icicle); setContentView(R.layout.main); Toast.makeText(a.this, "Touch and listen", Toast.LENGTH_SHORT).show(); Button button = (Button) findViewById(R.id.btn1); registerForContextMenu(button); button.setOnClickListener(new View.OnClickListener() { public void onClick(View v){ MediaPlayer mp = MediaPlayer.create(a.this, R.raw.myalo); mp.start(); Toast.makeText(a.this, "Eisai sto myalo", Toast.LENGTH_SHORT).show(); } }); @Override public void onCreateContextMenu(ContextMenu menu, View v,ContextMenuInfo menuInfo) { super.onCreateContextMenu(menu, v, menuInfo); menu.setHeaderTitle("Save As:"); menu.add(0, v.getId(), 0, "Ringtone"); } @Override public boolean onContextItemSelected(MenuItem item) { if(item.getTitle()=="Ringtone"){function1(item.getItemId());} else {return false;} return true; } public void function1(int id){ Toast.makeText(this, "Ringtone Saved", Toast.LENGTH_SHORT).show(); } }

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• WPF: How do I bind a Control to a formula composed of several dependency properties?

  - by Pablo

  Hi all, I'm working on Expression Blend and I'm currently designing a custom control which has a Grid with 5 rows inside, and also has two Dependency properties: "Value", and "Maximum". Three of the rows have fixed height, and what I'm trying to do is set the remaining rows height to "Value/Maximum" and "1-Value/Maximum" respectively. How do I go and do that? When I set the height to "Value" it seems to react, but when I go and set it to "Value/Maximum" it stops working. I'm still a bit new around WPF, so there must be another way to achieve what I'm intending, but after searching I couln't find my problem elsewhere. Code: <Grid x:Name="LayoutRoot" Width="Auto" Background="Transparent"> <Grid.RowDefinitions> <RowDefinition Height="32"/> <RowDefinition Height="{Binding Path=(Value/Maximum), ElementName=UserControl, Mode=Default}"/> <RowDefinition Height="16"/> <RowDefinition Height="{Binding Path=(1-Value/Maximum), ElementName=UserControl, Mode=Default}"/> <RowDefinition Height="32"/> </Grid.RowDefinitions> (...) By the way, Value is always a not negative double less than or equal to Maximum; so the result of the division will be number between 0.0 a 1.0. I want a "star" instead of "pixel" row height.

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• passing reference of class to another class android error

  - by prolink007

  I recently asked the precursor to this question and had a great reply. However, when i was working this into my android application i am getting an unexpected error and was wondering if everyone could take a look at my code and help me see what i am doing wrong. Link to the initial question: passing reference of class to another class My ERROR: "The constructor ConnectDevice(new View.OnClickListener(){}) is undefined" The above is an error detected by eclipse. Thanks in advance! Below are My code snippets: public class SmartApp extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.intro); final Button connectDeviceButton = (Button) findViewById(R.id.connectDeviceButton); connectDeviceButton.setOnClickListener( new View.OnClickListener() { @Override public void onClick(View v) { Thread cThread = new Thread(new ConnectDevice(this)); cThread.start(); } }); } } public class ConnectDevice implements Runnable { private boolean connected; private SmartApp smartAppRef; private ObjectInputStream ois; public ConnectDevice(SmartApp smartAppRef) { this.smartAppRef = smartAppRef; } }

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