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  • Best practice for debug Asserts during Unit testing

    - by Steve Steiner
    Does heavy use of unit tests discourage the use of debug asserts? It seems like a debug assert firing in the code under test implies the unit test shouldn't exist or the debug assert shouldn't exist. "There can be only one" seems like a reasonable principle. Is this the common practice? Or do you disable your debug asserts when unit testing, so they can be around for integration testing? Edit: I updated 'Assert' to debug assert to distinguish an assert in the code under test from the lines in the unit test that check state after the test has run. Also here is an example that I believe shows the dilema: A unit test passes invalid inputs for a protected function that asserts it's inputs are valid. Should the unit test not exist? It's not a public function. Perhaps checking the inputs would kill perf? Or should the assert not exist? The function is protected not private so it should be checking it's inputs for safety.

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  • How to pass javascript/jQuery settings from page to page in rails?

    - by aronchick
    When doing javascript manipulation of what's visible, how does one pass that from page to page (ideally in Rails)? For example, let's say I have the following simple jQuery code: <% link_to "Next Page", report_path %> <div class="clickable-div" style="background-color:#FFFFFF;"></div> <script> $('.clickable-div').click(function () { var color = $(this).css("background-color", "#000000"); }); </script> If it's not clear, the code is just supposed to change the color of the div based on whether or not it has been clicked. Regardless, there's also a link on the page that allows someone to go to the reporting page. What's a way to pass the state of the div to the action call? EDIT It seems unnecessary to do it in a session - am I wrong? This is just something from one page to the next, I couldn't care less anywhere else on the site. EDIT 2 To confirm, Rails needs to have access to the action that occurred in Javascript on the previous page.

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  • Keyboard not dismissed

    - by sgosha
    I am developing a messaging application that have SMS.app-like UI. Conversation screen has text input field at the bottom which is moved up with keyboard. Tapping on conversation area dismisses keyboard by calling resignFirstResponder method on UITextView that we use. This usually works fine, but users report a weird bug which I can't reproduce and fix. People say that sometimes onscreen keyboard doesn't go away when they tap on conversation area, though text input field loses input focus. Once the view enters that abnormal state users are able to type with keyboard, but text that is being entered is not visible anywhere. This bug happens in one of conversation views and since then no one text input field in other views doesn't work as expected. The only way to stop this weird behavior is killing application from multitasking bar. Even more weird thing is that keyboard stays visible while navigating between view controllers in UINavigationController. I noticed two things: - if tap on ' Anyone else experiencing same problems. Any ideas on what may cause this bug?

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  • Rails: creating a model in the new action

    - by Joseph Silvashy
    I have an interesting situation, well it's probably not that unique at all, but I'm not totally sure how to tackle it. I have a model, in this case a recipe and the user navigates to the new path /recipes/new however the situation is that I need to be able to have the user upload images and make associations to that model in the new action, but the model doesn't have an ID yet. So I assume I need to rethink my controller, but I don't want to have redirects and whatnot, how can accomplish this? Here is the basic controller, barebones obviously: ... def new # I should be creating the model first, so it has an ID @recipe = Recipe.new end def create @recipe = Recipe.new(params[:recipe]) if @recipe.save redirect_to @recipe else render 'new' end end ... update Perhaps I can have a column thats like state which could have values like new/incomplete/complete or what-have-you. I'm mostly trying to figure out what would also be most efficient for the DB. It would be nice if I could still have a url that said '/new', instead of it be the edit path with the id, for usability sake, but I'm not sure this can be simply accomplished in the new action of my controller. Thoughts?

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  • Cross-platform HTML application options

    - by Charles
    I'd like to develop a stand-alone desktop application targeting Windows (XP through 7) and Mac (Tiger through Snow Leopard), and if possible iPhone and Android. In order to make it all work with as much common code as possible (and because it's the only thing I'm good at), I'd like to handle the main logic with HTML and JS. Using Adobe AIR is a possibility. And I think I can do this with various application wrappers, using .NET for Windows XP, Objective C for iPhone, Java for Android and native "widget" platform support for Mac and Windows Vista & 7 (though I'd like to keep the widget in the foreground, so the Mac dashboard isn't ideal). Does anyone have any suggestions on where to start? The two sticking points are: I'll certainly need some form of persistent storage (cookies perhaps) to keep state between sessions I'll also probably need access to remote data files, so if I use AJAX and the hosting HTML file resides on the device, it will need to be able to do cross-domain requests. I've done this on the iPhone without any problems, but I'd be surprised if this were possible on other platforms. For me, Android and iPhone will be the easiest to handle, and it looks like I can use Adobe AIR to handle the rest. But I wanted to know if there are any other alternatives. Does anyone have any suggesions?

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  • ExecuteNonQuery: Connection property has not been initialized

    - by 20151012
    I get an error in my code: The error point at dbcom.ExecuteNonQuery();. Code(connection) public admin_addemp() { InitializeComponent(); con = new OleDbConnection(@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=|DataDirectory|\EMPS.accdb;Persist Security Info=True"); con.Open(); ds.Tables.Add(dt); ds.Tables.Add(dt2); } Code (Save button) private void save_btn_Click(object sender, EventArgs e) { OleDbCommand check = new OleDbCommand(); check.Connection = con; check.CommandText = "SELECT COUNT(*) FROM employeeDB WHERE ([EmployeeName]=?)"; check.Parameters.AddWithValue("@EmployeeName", tb_name.Text); if (Convert.ToInt32(check.ExecuteScalar()) == 0) { dbcom2 = new OleDbCommand("SELECT EmployeeID FROM employeeDB WHERE EmployeeID='" + tb_id.Text + "'", con); OleDbParameter param = new OleDbParameter(); param.ParameterName = tb_id.Text; dbcom.Parameters.Add(param); OleDbDataReader read = dbcom2.ExecuteReader(); if (read.HasRows) { MessageBox.Show("The Employee ID '" + tb_id.Text + "' already exist. Please choose another Employee ID."); read.Dispose(); read.Close(); } else { string q = "INSERT INTO employeeDB (EmployeeID, EmployeeName, IC, Address, State, " + " Postcode, DateHired, Phone, ManagerName) VALUES ('" + tb_id.Text + "', " + " '" + tb_name.Text + "', '" + tb_ic.Text + "', '" + tb_add1.Text + "', '" + cb_state.Text + "', " + " '" + tb_postcode.Text + "', '" + dateTimePicker1.Value + "', '" + tb_hp.Text + "', '" + cb_manager.Text + "')"; dbcom = new OleDbCommand(q, con); dbcom.ExecuteNonQuery(); MessageBox.Show("New Employee '" + tb_name.Text + "'- Successfuly Added."); } } else { MessageBox.Show("Employee name '" + tb_name.Text + "' already added into the database"); } ds.Dispose(); } I'm using Microsoft Access 2010 as my database and this is stand alone system. Please help me.

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  • .NET binary serialization conditionally without ISerializable

    - by SillyWhy
    I got 2 classes, for example: public class A { private B b; ... } public class B { ... } I need to serialize an object A using BinaryFormatter. When remoting it shall include the field b, but not when serialize to file. Here is what I added: [Serializable] public class A : MarshalByRefObject { private B b; [OnSerializing] private void OnSerializing(StreamingContext context) { if (context.State == StreamingContextStates.File) { this.b = null; } } ... } [Serializable] public class B : MarshalByRefObject { ... } I think this is a bad design because if another class C also contains B, in class C we must add the duplicate OnSerializing() logic as in A. Class B should decide what to do, not class A or C. I don't want to use ISerializable interface because there are too many variables in class B have to be added to SerializationInfo. I can create a SerializationSurrogate for class B, which perform nothing in GetObjectData() & SetObjectData(), then use it when serializing to file. However the same maintenance issue because whoever modify class B can't notice what going to happen during serialization & the existence of SerializationSurrogate. Is there a better alternative?

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  • Hide / Show menu code not working after postback

    - by WraithNath
    I have a button on my web page that toggles the menu, After a postback the menu comes back despite me updating a hidden field value to store its state. Am I doing something wrong here? If there is a better way of doing it, let me know! Markup: <asp:Button ID="btnMenu" runat="server" Text="Hide Menu" UseSubmitBehavior="False" OnClientClick="return toggleMenu(this);" /> <asp:Panel runat="server" ID="pnlMenuToggle"> //Main Menu </asp:Panel> <asp:Panel runat="server" ID="pnlSubMenuToggle"> //Sub Menu </asp:Panel> <asp:HiddenField ID="hfMenuState" runat="server" Value="true" /> <script> //Toggles menu visibility function toggleMenu(menuButton) { var menuVisible = $('#<%=hfMenuState.ClientID%>').val() == 'true' ? true : false; $('#<%=pnlMenuToggle.ClientID%>').slideToggleWidth(); $('#<%=pnlSubMenuToggle.ClientID%>').slideToggle('slow'); //Update whether the menu is visible menuVisible = !menuVisible; //Update menu button text $(menuButton).val(menuVisible ? 'Hide Menu' : 'Show Menu'); $('#<%=hfMenuState.ClientID%>').val(menuVisible) return false; } </script> Code Behind: (Page Load) bool menu = Convert.ToBoolean( hfMenuState.Value ); pnlMenuToggle.Visible = menu; pnlSubMenuToggle.Visible = menu; The javascripts updates the hidden field value but it looks like this is never posted back to the server. What can I do to make sure the menu stays hidden after postbacks. I have also tried putting the hidden field in an Update Panel with Update Mode set to Always

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  • Converting to MVC3 - some views still want 'System.Web.Mvc, Version=1.0.0.0,

    - by justSteve
    I've used the directions from the release notes and have been able to navigate most pages - my unit tests are not comprehensive but most all pass. However...when I attempt to edit an existing or create a new user I'm getting the error pasted below - notice that it's references version=1... - this project started life as a v1 and was converted to mvc2 at the RTM. I'm still working with V2 projects but no longer any v1. Am i due for a GAC cleansing? Server Error in '/' Application. Could not load file or assembly 'System.Web.Mvc, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The system cannot find the file specified. === Pre-bind state information === LOG: User = STUDIO11\mUser LOG: DisplayName = System.Web.Mvc, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35 (Fully-specified) LOG: Appbase = file:///C:/Users/C:\Users\[path to project]/ LOG: Initial PrivatePath = C:\Users\[path to project]\bin Calling assembly : App_Web_qcjylaoc, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null. === LOG: This bind starts in default load context. LOG: Using application configuration file: C:\Users\[path to project]\web.config LOG: Using host configuration file: LOG: Using machine configuration file from C:\Windows\Microsoft.NET\Framework\v4.0.30319\config\machine.config. LOG: Post-policy reference: System.Web.Mvc, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35 LOG: The same bind was seen before, and was failed with hr = 0x80070002.

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  • Sending a password securely using gwt and app engine?

    - by user246114
    Hi, I set up session handling on a google app project. This is supposed to allow my users to login and maintain state across pages. I just dumped it into the default greeting service to try it out: public class GreetingServiceImpl extends RemoteServiceServlet implements GreetingService { public void sessionTest(String username) { HttpSession session = getThreadLocalRequest().getSession(false); session.setAttribute("username", username); } } then attempting to pull it out in my landing project.jsp page: <% String username = null; HttpSession mysession = request.getSession(false); if (mysession.getAttribute("username") != null) { username = (String)mysession.getAttribute("username"); } else { username = "(not logged in yet)"; } <p>You are: <%= username %> </p> %> It works, but I don't know how to send the data in sessionTest() securely. If I were sending the user's password in there too, it would be in the clear. This would be ok (I think) if I was using https, but google app engine does not allow you to use https under custom domains (like www.mysite.com), they have to be under the (mysite.appspot.com) domain. I'm kind of stuck here - how do we send passwords securely? If I was using php, I think I could use digest authentication (I'm not too experienced here) - can we do something like that with gwt + gae? Thanks

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  • Expanders inside listbox leaving blank space on collapse

    - by siz
    We have a rather complex UI that is presenting some problems for us. I have a ListBox that contains a set of DataItems. The DataTemplate for each item is an Expander. The header is text, the content of the Expander is a ListBox. The ListBox contains SubDataItems. The DataTemplate for each SubDataItem is an Expander. Here is a simplified XAML in which I reproduce the issue: <ListBox ItemsSource="{Binding Items}"> <ListBox.ItemTemplate> <DataTemplate> <Expander Header="{Binding Header}"> <ListBox ItemsSource="{Binding SubItems}"> <ListBox.ItemTemplate> <DataTemplate> <Expander Header="{Binding SubHeader}"> <Grid Height="40"> <TextBlock Text="{Binding SubText}" /> </Grid> </Expander> </DataTemplate> </ListBox.ItemTemplate> </ListBox> </Expander> </DataTemplate> </ListBox.ItemTemplate> </ListBox> There is a problem with how the layout is produced. If any Expander corresponding to the SubDataItem is expanded, the ListBoxItem containing this ListBox (the Expander.Content in the parent DataTemplate) correctly requests more space. So I can expand all SubDataItems and correctly see my data. However, when I collapse, the space I previously asked to expand, remains blank, instead of being reclaimed by the ListBoxItem. This is a problem because if I have say 10 SubDataItems and happen to expand all of them at the same time and then collapse, there is a significant amount of white space wasting my real estate. How can I force WPF to resize the ListBoxItem to the correct state?

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  • How to get notified about changes of the history via history.pushState?

    - by Felix Kling
    So now that HTML5 introduces history.pushState to change the browsers history, websites start using this in combination with Ajax instead of changing the fragment identifier of the URL. Sadly that means that those calls cannot be detect anymore by onhashchange. My question is: Is there a reliable way (hack? ;)) to detect when a website uses history.pushState? The specification does not state anything about events that are raised (at least I couldn't find anything). I tried to create a facade and replaced window.history with my own JavaScript object, but it didn't have any effect at all. Further explanation: I'm developing a Firefox add-on that needs to detect these changes and act accordingly. I know there was a similar question a few days ago that asked whether listening to some DOM events would be efficient but I would rather not rely on that because these events can be generated for a lot of different reasons. Update: Here is a jsfiddle (use Firefox 4 or Chrome 8) that shows that onpopstate is not triggered when pushState is called (or am I doing something wrong? Feel free to improve it!). Update 2: Another (side) problem is that window.location is not updated when using pushState (but I read about this already here on SO I think).

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  • Reserve space for initially hidden widget in QVBoxLayout

    - by Skinniest Man
    I am using a QVBoxLayout to arrange a vertical stack of widgets. I want some of them to be initially hidden and only show up when a check box is checked. Here is an example of the code I'm using. MyWidget::MyWidget(QWidget *parent) : QWidget(parent) { QVBoxLayout *layout = new QVBoxLayout(this); QLabel *labelLogTypes = new QLabel(tr("Log Types")); m_checkBoxCsv = new QCheckBox(tr("&Delimited File (CSV)")); m_labelDelimiter = new QLabel(tr("Delimiter:")); m_lineEditDelimiter = new QLineEdit(","); checkBoxCsv_Toggled(m_checkBoxCsv-isChecked()); connect(m_checkBoxCsv, SIGNAL(toggled(bool)), SLOT(checkBoxCsv_Toggled(bool))); QHBoxLayout *layoutDelimitedChar = new QHBoxLayout(); layoutDelimitedChar-addWidget(m_labelDelimiter); layoutDelimitedChar-addWidget(m_lineEditDelimiter); m_checkBoxXml = new QCheckBox(tr("&XML File")); m_checkBoxText = new QCheckBox(tr("Plain &Text File")); // Now that everything is constructed, put it all together // in the main layout. layout-addWidget(labelLogTypes); layout-addWidget(m_checkBoxCsv); layout-addLayout(layoutDelimitedChar); layout-addWidget(m_checkBoxXml); layout-addWidget(m_checkBoxText); layout-addStretch(); } MyWidget::checkBoxCsv_Toggled(bool checked) { m_labelDelimiter-setVisible(checked); m_lineEditDelimiter-setVisible(checked); } I want m_labelDelimiter and m_lineEditDelimiter both to be initially invisible and I want their visibility to toggle with the state of m_checkBoxCsv. This code acheives the functionality I desire, but it doesn't seem to reserve space for the two initially hidden widgets. When I check the checkbox, they become visible, but everything is kind of scrunched to accomodate them. If I leave them initially visible, everything is laid out just the way I would like it. Is there any way to make the QVBoxLayout reserve space for these widgets even if they're initially invisible?

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  • How to get JTree expanded?

    - by Dzmitry Zhaleznichenka
    I have a wizard with several screens where user has to fill his/her details for further processing. At the second screen I have a radio group with three radio buttons that enable additional elements. To proceed, user has to choose one of them. When user selects third button, single-selection JTree filled in with data enables and user has to select an option from it. Then user has to press "Next" to get to next screen. The option he\she had selected is stored as a TreePath. So far so good. My problem is the following. If the user wants to come back from the following screen to the screen with a JTree, I want to provide him\her with the JTree expanded to the option that had been selected and to highlight the option. However, whatsoever I try to do for that (any combinations of expandPath, scrollPathToVisible, addSelectionPath, makeVisible) always provides me with a collapsed tree. I try to expand both leaves and nodes. My code looks like this: rbProcessJTree.setSelected(isProcessJTree()); if (null != getSelectedTablePath()){ trTables.addSelectionPath(getSelectedTablePath()); trTables.expandPath(getSelectedTablePath()); trTables.scrollPathToVisible(getSelectedTablePath()); } When setSelected() is called, state change listener is invoked that enables JTree. The model is loaded during the form initialization. Each time I switch between screens, I save the input data from previous screen and dispose it. Then, when I need to open previous screen back, I save data from the following screen, dispose it, load data to this screen and show it. So each time the screen is generating from scratch. Could you please explain, what sequence of operations has to be done to get JTree expanded in a newly created form,with data model loaded and selection path provided?

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  • How to repair Java in Ubuntu after trying to switch to Java 6 using update-java-alternatives

    - by Kau-Boy
    I tried to switch from Java 5 to Java 6 using the "update-java-alternatives" command like explained on this page: https://help.ubuntu.com/community/Java But afterwards I get the following error when I tried to execute java: root@webserver:~# java Error occurred during initialization of VM Could not reserve enough space for object heap Could not create the Java virtual machine. I also tried to reinstall the java binaries using "apt-get" but I didn't succeed reinstalling it. I would like to post the "apt-get" errors, but unfortunately I don't know how to print out the error messages in English and not in German. My system is a Ubuntu 8.04 ROOT server. Here is the (Google translated) english text tring to install Java 6 again: root@server:~# apt-get install sun-java6-jdk Reading package lists ... Ready Dependency tree Reading state information ... Ready sun-java6-jdk is already the newest version. sun-java6-jdk set to manually installed. 0 upgraded, 0 newly installed, 0 to remove and 86 not upgraded. 1 not fully installed or removed. After this operation, 0B of additional disk space will be used. Set up a sun-java6-bin (6-03-0ubuntu2) ... Could not create the Java virtual machine. dpkg: error processing sun-java6-bin (- configure): Subprocess post-installation script returned error exit status 1 Errors were encountered while processing: sun-java6-bin E: Sub-process / usr / bin / dpkg returned an error code (1) I hope that this might help you helping me.

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  • Is this feasbile with GIS?

    - by Gnu Engineer
    I'm just getting myself to familiarize with GIS but i like to know before hand if the following is feasible with current GIS apps/tools... I get the point for an address by geocoding. Easy part. Now if the point falls within a boundary (may be a city/county/state) then i need to get the data (any id/flag) associated with the boundary. Based on the id/flag i then apply some business logic. My question is... How do i define the boundary? What tools should i use for it? How can i store the boundary definition in database in order to check if the point falls within it? This has to be done in the back end and not in visual maps as we don't intend to show/use maps. How do i associate my custom data (id/flag) with the above boundary definition? Hope i'm having right assumption on capabilities of GIS. Most of examples what i see is around people trying to show maps with data which is exactly not what i'm looking for. Also please suggest me some tools/books on this.

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  • How can I serialize functions using JSON or some other serialization library?

    - by Oragamster
    I am trying to create a program that uses javascript to write a simple textadventure that I can then post on my blog and run on my iphone. I have run into a problem though. I was trying to make it so that my program would save it's state into cookies using JSON to convert it into strings and then post it into a cookie but then I realised that I couldn't serialize the functions that are on my item object. I was trying to make it so that my item would have an associative array that would contain the name of the use as the key and the function as the value. This worked well untill I tried to serialize it. I learned that I could create a JSON like serialization for functions by storing the body into a string and using escape charectors for the double quotes but for some reason I was unable to make my cookie with the function as the string stored. When I posted the cookie and then tried to get it back the string wasn't there. My code and the over all project are on my site if you want to look at that, though my full code including the item actions are not posted yet.

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  • How to re-enable the idle timer in ios once it has been disabled (to allow the display to sleep again)?

    - by lindon fox
    I have figured out how to stop an iOS device from going to sleep (see below), but I am having troubles undoing that setting. According to the Apple Documentation, it should just be changing the value of the idleTimerDisabled property. But when I test this, it does not work. This is how I am initially stopping the device from going to sleep: //need to switch off and on for it to work initially [UIApplication sharedApplication].idleTimerDisabled = NO; [UIApplication sharedApplication].idleTimerDisabled = YES; I would have thought that the following would do the trick: [UIApplication sharedApplication].idleTimerDisabled = NO; From the Apple Documentation: The default value of this property is NO. When most applications have no touches as user input for a short period, the system puts the device into a "sleep” state where the screen dims. This is done for the purposes of conserving power. However, applications that don't have user input except for the accelerometer—games, for instance—can, by setting this property to YES, disable the “idle timer” to avert system sleep. Important: You should set this property only if necessary and should be sure to reset it to NO when the need no longer exists. Most applications should let the system turn off the screen when the idle timer elapses. This includes audio applications. With appropriate use of Audio Session Services, playback and recording proceed uninterrupted when the screen turns off. The only applications that should disable the idle timer are mapping applications, games, or similar programs with sporadic user interaction. Has anyone come across this problem? I am testing on iOS6 and iOS5. Thanks in advance.

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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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  • How to convert a lambda to an std::function using templates

    - by retep998
    Basically, what I want to be able to do is take a lambda with any number of any type of parameters and convert it to an std::function. I've tried the following and neither method works. std::function([](){});//Complains that std::function is missing template parameters template <typename T> void foo(function<T> f){} foo([](){});//Complains that it cannot find a matching candidate The following code does work however, but it is not what I want because it requires explicitly stating the template parameters which does not work for generic code. std::function<void()>([](){}); I've been mucking around with functions and templates all evening and I just can't figure this out, so any help would be much appreciated. As mentioned in a comment, the reason I'm trying to do this is because I'm trying to implement currying in C++ using variadic templates. Unfortunately, this fails horribly when using lambdas. For example, I can pass a standard function using a function pointer. template <typename R, typename...A> void foo(R (*f)(A...)) {} void bar() {} int main() { foo(bar); } However, I can't figure out how to pass a lambda to such a variadic function. Why I'm interested in converting a generic lambda into an std::function is because I can do the following, but it ends up requiring that I explicitly state the template parameters to std::function which is what I am trying to avoid. template <typename R, typename...A> void foo(std::function<R(A...)>) {} int main() { foo(std::function<void()>([](){})); }

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  • Recreating a workflow instance with the same instance id

    - by Miron Brezuleanu
    We have some objects that have an associated workflow instance. The objects are identified with a GUID, which is also the GUID of the workflow instance associated with the object. We need to restart (see NOTE 3 for the meaning of 'restart') the workflow instance if the workflow definition changed (there is no state in the workflow itself and it is written to support restarting in this manner). The restarting is performed by calling Terminate on the WorkflowInstance, then recreating the instance with the same GUID. The weird part is that this works every other attempt (odd attempts - the workflow is stopped, but for some reason doesn't restart, even attempt - the already terminated workflow is recreated and started successfully). While I admit that using 'second hand' GUIDs is a sign of extraordinary cheapness (and something we plan to change), I'm wondering why this isn't working. Any ideas? NOTES: The terminated workflow instance is passivated (waiting for a notification) at the time of the termination. The Terminate call successfully deletes the data persisted in the database for that instance. We're using 'restarting' with a meaning that's less common in the context of WF - not restarting a passivated instance, but force the workflow to start again from the beginning of its definition. Thanks!

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  • I just discovered why all ASP.Net websites are slow, and I am trying to work out what to do about it

    - by James
    I just discovered that every request in an ASP.Net web application gets a Session lock at the begging of a request, and then releases it at the end of the request!!! I mean, WTF Microsoft! In case the implication is lost on you, as it was from me at first, this basically means the following: Anytime an ASP.Net webpage is taking a long time to load (maybe due to a slow database call or whatever), and the user decides they want to navigate to a different page because they are tired of waiting, THEY CANT! The ASP.Net session lock forces the new page request to wait until the original request has finished its painfully slow load. Arrrgh. Anytime an UpdatePanel is loading slowly, and the user decides to navigate to a different page before the UpdadePanel has finished updating... THEY CANT! The ASP.Net session lock forces the new page request to wait until the original request has finished its painfully slow load. Double Arrrgh! So what are the options? So far I have come up with: Implement a Custom SessionStateDataStore, which ASP.Net supports. I haven't found too many out there to copy, and it seems kind of high risk and easy to mess up. Keep track of all requests in progress, and if a request comes in from the same user, cancel the original request. Seems kind of extreme, but it would work (I think) Don't user Session! When I need some kind of state for the user, I could just user Cache instead, and key items on the authenticated user's name, or some such thing. Again seems kind of extreme I really can't believe that the ASP.Net Microsoft team would have left such a huge performance bottleneck in the framework at version 4.0! Am I missing something obvious? How hard would it be to use a ThreadSafe collection for the Session? Arrrrghhhhhh. Any advice much appreciated.

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  • Is it possible to load an entire SQL Server CE database into RAM?

    - by DanM
    I'm using LinqToSql to query a small SQL Server CE database. I've noticed that any operations involving sub-properties are disappointingly slow. For example, if I have a Customer table that is referenced by an Order table via a foreign key, LinqToSql will automatically create an EntitySet<Order> property. This is a nice convenience, allowing me to do things like Customer.Order.Where(o => o.ProductName = "Stopwatch"), but for some reason, SQL Server CE hangs up pretty bad when I try to do stuff like this. One of my queries, which isn't really that complicated takes 3-4 seconds to complete. I can get the speed up to acceptable, even fast, if I just grab the two tables individually and convert them to List<Customer> and List<Order>, then join then manually with my own query, but this is throwing out a lot of the appeal of LinqToSql. So, I'm wondering if I can somehow get the whole database into RAM and just query that way, then occasionally save it. Is this possible? How? If not, is there anything else I can do to boost the performance? Note: My database in its initial state is about 250K and I don't expect it to grow to more than 1-2Mb. So, loading the data into RAM certainly wouldn't be a problem from a memory point of view.

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  • Getting a particular menu item from MainMenu

    - by Garry
    I have a nib (winA.xib) that contains a window. My app delegate contains an NSWindowController subclass called WinAController. WinAController has a property (NSMenu *mainMenu) that I want to point to the MainMenu. I have set it after I instantiate WinAController with this code: WinAController = [[WinAController alloc] initWithWindowNibName:@"WinA"]; WinAController.mainMenu = [NSApp mainMenu]; I have a menu item underneath the "Window" top-level menu item on MainMenu that invokes the [WinAController showWindow] method and displays WinA. I want to toggle the on/off state of this menu item depending on whether WinA is visible or not. WinAController also has another property (NSMenuItem *myMenuItem). How can I get a reference to a sub menu of the "Window" top-level menu item. The title of sub menu item I want to get is "Command". I have tried this: if (mainMenu != nil) { myMenuItem = [mainMenu itemAtIndex:[mainMenu indexOfItemWithTitle:@"Command"]]; } But it doesn't seem to work. Where am I going wrong? Thanks,

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  • What techniques can I employ to create a series of UI Elements from a collection of objects using WP

    - by elggarc
    I'm new to WPF and before I dive in solving a problem in completely the wrong way I was wondering if WPF is clever enough to handle something for me. Imagine I have a collection containing objects. Each object is of the same known type and has two parameters. Name (a string) and Picked (a boolean). The collection will be populated at run time. I would like to build up a UI element at run time that will represent this collection as a series of checkboxes. I want the Picked parameter of any given object in the collection updated if the user changes the selected state of the checkbox. To me, the answer is simple. I iterate accross the collection and create a new checkbox for each object, dynamically wiring up a ValueChanged event to capture when Picked should be changed. It has occured to me, however, that I may be able to harness some unknown feature of WPF to do this better (or "properly"). For example, could data binding be employed here? I would be very interested in anyone's thoughts. Thanks, E FootNote: The structure of the collection can be changed completely to better fit any chosen solution but ultimately I will always start from, and end with, some list of string and boolean pairs.

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