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  • Textblock doesnt get updated when rendered in memory?

    - by veechi
    I have a text block which as part of a custom control.I added the custom control as a child of grid which in turn is added as child of a Canvas.All of these contorl are instantiated in memory and are not rendered on the UI.When I update the value of the TextBlock and emboss the canvas on an image, the updated value doesnt appear on the embossed image.Here is the code snippet:- System.Windows.Controls.Canvas embossCanvas = new System.Windows.Controls.Canvas(); System.Windows.Controls.Grid grid = new Grid(); MyControl myctrl= new MyControl(); int wd = (int)myctrl.ActualWidth; int ht = (int)myctrl.ActualHeight; embossCanvas.Width = wd; embossCanvas.Height = ht; grid.Children.Add(myctrl); embossCanvas.Children.Add(grid); myctrl.txtBlk.UpdateLayout(); grid.UpdateLayout(); embossCanvas.Measure(new System.Windows.Size(embossCanvas.Width, embossCanvas.Height)); embossCanvas.Arrange(new System.Windows.Rect(0, 0, embossCanvas.Width, (int)embossCanvas.Height)); embossCanvas.UpdateLayout(); RenderTargetBitmap renderBmp = new RenderTargetBitmap(wd, ht, 96, 96, System.Windows.Media.PixelFormats.Default); renderBmp.Render(embossCanvas);

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  • [IE6] Cannot upload non-existent file

    - by geff_chang
    I am asking the same question as this: http://stackoverflow.com/questions/691323/trying-to-upload-a-non-existent-file-in-internet-explorer-form-is-not-submitted I'm not sure if the topic starter found a solution, since he did not post the answer. So, I'd like to ask you guys this question again. I have type=input in my form, and a submit button. If I type garbage input into the textbox (like the text "abc") in the file control's textbox, and click the submit button, the form is not submitted to the server. AND, no feedback is given to the user. Instead of this "Is-the-submit-button-broken?" behavior, is there a way I could notify the user that the file does not exist? (I am aware this is not possible, except with ActiveX, but I don't want to go into that) My client wants to hide the textbox of the file control, but I'm not sure if this is a good design. What do you guys suggest? (If it makes any difference, I am also using this jquery plugin: http://www.fyneworks.com/jquery/multiple-file-upload/)

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  • Firefox not honoring must-revalidate cache headers returned by jQuery.ajax() request

    - by Oliver Weichhold
    UPDATE 1: Judging by this thread I am not the only one having this problem in FF 12 and only in 12. UPDATE 2: The problem does not seem to be limited to Ajax requests. From the looks of it everything that makes it into Firefox 12's cache will be fetched from there. No matter what. The server can specify cache control headers all day long. Bummer! What I'm trying to achieve is the following behavior: Browser may cache the response without revalidating for up to 5 minutes I don't care if the browser revalidates on every request (Both Chrome and IE9 do for example) When the expiration is up the browser MUST revalidate (which in my case will result in fresh data) Chrome and IE9 exhibit the desired behavior when issuing a jquery.ajax() request with ifModified: true and cache: true while Firefox 12 never revalidates, which poses a serious problem. These are the actual response headers: HTTP/1.1 200 OK Server: nginx Date: Sun, 03 Jun 2012 07:13:43 GMT Content-Type: text/javascript; charset=UTF-8 Transfer-Encoding: chunked Connection: keep-alive Vary: Accept-Encoding Cache-Control: private, must-revalidate, max-age=300 Last-Modified: Sun, 03 Jun 2012 07:07:13 GMT Content-Encoding: gzip Any suggestions?

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  • How to get TextWidth of string (without Canvas)?

    - by lyborko
    Hi, I would like to get text width of a string before an application starts. Everything works fine untill Application.MainForm canvas present. The problem is, when I try dynamicaly create TOrdinarium in the OnCreate event of the app. main form, "Canvas does not allow drawing" error occures. (Application.MainForm is nil....). I tried several ways to create Canvas dynamicaly (one of them is written below), but it can not measure text sizes without being attached to parented control. Is there way how to make it work somehow? Thanx I tried this: TOrdinarium = class (TCustomControl) private function GetVirtualWidth:integer; end; constructor TOrdinarium.Create(AOwner:TComponent); begin inherited; Width:=GetVirtualWidth; end; function TOrdinarium.GetVirtualWidth:integer; var ACanvas : TControlCanvas; begin ACanvas := TControlCanvas.Create; TControlCanvas(ACanvas).Control := Application.MainForm; ACanvas.Font.Assign(Font); result:=ACanvas.TextWidth('0'); ACanvas.Free; end;

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  • C++ creating generic template function specialisations

    - by Fire Lancer
    I know how to specialise a template function, however what I want to do here is specialise a function for all types which have a given method, eg: template<typename T> void foo(){...} template<typename T, if_exists(T::bar)>void foo(){...}//always use this one if the method T::bar exists T::bar in my classes is static and has different return types. I tried doing this by having an empty base class ("class HasBar{};") for my classes to derive from and using boost::enable_if with boost::is_base_of on my "specialised" version. However the problem then is that for classes that do have bar, the compiler cant resolve which one to use :(. template<typename T> typename boost::enable_if<boost::is_base_of(HasBar, T>, void>::type f() {...} I know that I could use boost::disable_if on the "normal" version, however I do not control the normal version (its provided by a third party library and its expected for specialisations to be made, I just don't really want to make explicit specialisations for my 20 or so classes), nor do I have that much control over the code using these functions, just the classes implementing T::bar and the function that uses it. Is there some way to tell the compiler to "always use this version if possible no matter what" without altering the other versions?

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  • Problems with Unity BuildUp Method

    - by Voice
    Hi everybody) I'm using Unity App Block for my project (version 1.2.0.0). I have a problem with Unity Container BuildUp method which I'm using for my ascx controls. Here is some code (that's pretty simple) public class BaseUserControl<T>:UserControl where T:class { protected override void OnInit(EventArgs e) { InjectDependencies(); base.OnInit(e); } protected virtual void InjectDependencies() { var context = HttpContext.Current; if (context == null) { return; } var accessor = context.ApplicationInstance as IContainerAccessor; if (accessor == null) { return; } var container = accessor.Container; if (container == null) { throw new InvalidOperationException("No Unity container found"); } container.BuildUp<T>(this as T); } } This method is called in base control for ascx controls in my solution. And here the property that should be injected in child control: [Dependency] private IStock Stock { get; set; } So after buildup Stock property is still empty. Resolve method works fine for IStock with the same container and configuration. I've tried buildup with simple test class with only one property IStock and got the same result. So what can be wrong with buildup?

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  • I want to prevent ASP.NET GridView from reacting to the enter button

    - by StephaneT
    I have an ASP.NET page with a gridview control on it with a CommandButton column with delete and select commands active. Pressing the enter key causes the first command button in the gridview to fire, which deletes a row. I don't want this to happen. Can I change the gridview control in a way that it does not react anymore to pressing the enter key? There is a textbox and button on the screen as well. They don't need to be responsive to hitting enter, but you must be able to fill in the textbox. Currently we popup a confirmation dialog to prevent accidental deletes, but we need something better than this. This is the markup for the gridview, as you can see it's inside an asp.net updatepanel (i forgot to mention that, sorry): (I left out most columns and the formatting) <asp:UpdatePanel ID="upContent" runat="server" UpdateMode="Conditional"> <Triggers> <asp:AsyncPostBackTrigger ControlID="btnFilter" /> <asp:AsyncPostBackTrigger ControlID="btnEdit" EventName="Click" /> </Triggers> <ContentTemplate> <div id="CodeGrid" class="Grid"> <asp:GridView ID="dgCode" runat="server"> <Columns> <asp:CommandField SelectImageUrl="~/Images/Select.GIF" ShowSelectButton="True" ButtonType="Image" CancelText="" EditText="" InsertText="" NewText="" UpdateText="" DeleteImageUrl="~/Images/Delete.GIF" ShowDeleteButton="True" /> <asp:BoundField DataField="Id" HeaderText="ID" Visible="False" /> </Columns> </asp:GridView> </div> </ContentTemplate> </asp:UpdatePanel>

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  • IE textarea wrap bug?

    - by user2227033
    It seems that IE starting from IE7 to IE10 wraps text in the textarea control incorrectly when using \n (or \r\n - doesn't matter - results are the same). Is this a bug in IE or they treat the html standard differently than other browsers - who is right? I have defined: <textarea id="TextArea1" runat="server" style="width: 190px; height: 390px; white-space: normal; word-wrap: normal; overflow: scroll" ></textarea> When I try to add long string like "VeryLongStringEndingWithNewLine\n" by using JavaScript code (obj.value += text;) the text is shown in one line with scroll (this is ok) but added with an additional empty line (\r\n) - why? When I try to add short string like "Short\n" multiple times, again via JavaScript code the text is on the same line (should be on the separate lines because normal wrapping should be applied). Moreover when I do postback then all \r\n's are replaced with spaces (why?) and then text parsed correctly (assuming if I used spaces instead of crlf normal wraping with space only wraps when does not fit in the area). When using FF or Chrome same control behaves correctly - long lines are shown without an additional empty next line, short lines are on the different lines, no replacement with spaces when doing postback. I know I could probably use other options or white space characters, but I feel that above is not correct about IE. Any comments? Mindaugas

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  • Force Installing a Radeon HD 2100 on Windows 8

    - by Click Ok
    I'm trying force installing a Radeon HD 2100 on Windows 8. I've found that link from AMD with the drivers for Windows7: http://support.amd.com/us/gpudownload/windows/legacy/Pages/legacy-radeonaiw-vista64.aspx I know too that AMD will stop support Radeon HD 400 and older: http://www.techspot.com/news/48321-amd-drops-windows-8-support-for-radeon-hd-4000-and-older.html Now, let's go to the problem. If I try install the 12.6 driver, Windows will stick with the "basic display adapter", and this is bad for 3d games like Minecraft, that runs really slow now compared with the previous Windows7 installation. Forcing install the catalyst driver can help to fix it. So, I follow that steps: Extract the Catalist Driver (C:\AMD\Support\12-6-legacy_vista_win7_64_dd_ccc_whql) Right click the "basic display adapter" on device manager, and "update driver" Search on PC I will choose the driver "With Disk" "C:\AMD\Support\12-6-legacy_vista_win7_64_dd_ccc_whql\Packages\Drivers\Display\W76A_INF" There is a big list of drivers and the nearest driver to HD 2100 is "Radeon HD 2350 Series" My questions: Why isn't "Radeon HD 2100 Series" listed? (or Where is it listed?) In theory it must be listed" The first link above show that "This article applies to the following configuration(s):" (...) "AMD Radeon HD 2000 Series" Am I doing something wrong?

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  • server controls complex properties with sub collections.

    - by Richard Friend
    Okay i have a custom server control that has some autocomplete settings, i have this as follows and it works fine. /// <summary> /// Auto complete settings /// </summary> [System.ComponentModel.DesignerSerializationVisibility (System.ComponentModel.DesignerSerializationVisibility.Content), PersistenceMode(PersistenceMode.InnerProperty), Category("Data"), Description("Auto complete settings"), NotifyParentProperty(true)] public AutoCompleteLookupSettings AutoComplete { private set; get; } I also have a ParameterCollection that is really related to the auto complete settings, currently this collection resides off the control itself like so : /// <summary> /// Parameters for any data lookups /// </summary> [System.ComponentModel.DesignerSerializationVisibility(System.ComponentModel.DesignerSerializationVisibility.Content), PersistenceMode(PersistenceMode.InnerProperty)] public ParameterCollection Parameters { get; set; } What i would like to do is move the parameter collection inside of the AutoCompleteSettings as it really relates to my autocomplete, i have tried this but to no avail.. I would like to move from <cc1:TextField ID="TextField1" runat='server'> <AutoComplete MethodName="GetTest" TextField="Item1" TypeName ="AppFrameWork.Utils" /> <Parameters> <asp:ControlParameter ControlID="txtTest" PropertyName="Text" Name="test" /> </Parameters> </cc1:TextField> To <cc1:TextField ID="TextField1" runat='server'> <AutoComplete MethodName="GetTest" TextField="Item1" TypeName ="AppFrameWork.Utils" > <Parameters> <asp:ControlParameter ControlID="txtTest" PropertyName="Text" Name="test" /> </Parameters> </AutoComplete> </cc1:TextField>

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  • Display Consistent Value of an Item using MVVM and WPF

    - by Blake Blackwell
    In my list view control (or any other WPF control that will fit the situation), I would like to have one TextBlock that stays consistent for all items while another TextBlock that changes based on the value in the ObservableCollection. Here is how my code is currently laid out: XAML <ListView ItemsSource="{Binding Path=MyItems, Mode=TwoWay}"> <ListView.ItemTemplate> <DataTemplate> <StackPanel Orientation="Horizontal"> <TextBlock x:Name="StrVal" Text="{Binding StrVal}" /> <TextBlock x:Name="ConstVal" Text="{Binding MyVM.ConstVal}" /> </StackPanel> </DataTemplate> </ListView.ItemTemplate> </ListView> Model public class MyItem { public string StrVal { get; set; } } ViewModel public class MyVM { public MyVM() { ObservableCollection<MyItem> myItems = new ObservableCollection<MyItem>(); for (int i = 0 ; i < 10; i++) myItems.Add(new MyItem { StrVal = i.ToString()}); MyItems = myItems; ConstVal = "1"; } public string ConstVal { get; set; } public ObservableCollection<MyItem> MyItems { get; set; } } Code Behind this.DataContext = new MyVM(); The StrVal property repeats correctly in the ListView, but the ConstVal TextBlock does not show the ConstVal that is contained in the VM. I would guess that this is because the ItemsSource of the ListView is MyItems and I can't reference other variables outside of what is contained in the MyItems. My question is: How do I get ConstVal to show the value in the ViewModel for all listviewitems that will be controlled by the Observable Collection of MyItems.

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  • D-Link wireless router losing outbound data

    - by gsteinert
    I have a Linux box running the Apache web server behind a D-Link wireless router (nothing fancy, just standard kit that comes with Virgin Media broadband). My issue is that when requesting web pages (from within the network or via the web), the back end of the page seems to be being dropped. For example, I tried to display a text-only file, and all I could get was the first 40-70% of the file (it changed slightly with each refresh). The apache access logs show that only part of the data was being sent (~6000 bytes instead of the 12000+ bytes of the file). Removing my router from the equation fixes the issue and I can download any files no matter the size with no problems. My theory is that the uploaded packets are either being dropped or held up by the config of the router. Is there anything I can do to alleviate the problem? (Perhaps a way of reconfiguring the router to upload packets harder/better/faster/stronger or an option in apache that provides a workaround) As a last resort I will get a second NIC for my Linux box and turn it into a router, but that would mean the box will be on 24/7... not the most ideal of circumstances. Gary

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  • How to handle 30k files in a project which requires them?

    - by Jeremiah
    Visual Studio 2010 RC - Silverlight Application We have a library of images that we need to have access to. They are given to us from a vendor (through an installer) and they are not in a database, they are files in a folder (a very large monster of a folder). We do not control when the images change, so the vendor needs to be able to override them individually. We get updates frequently enough from this vendor to state that these images change "randomly" and without our (programmer) knowledge. The problem: I don't want 30K images in SVN. Heck, I don't even want to imagine them in my Solution. However, our application requires them in order to run properly. So, our build/staging servers need access to these images (we have two build servers). The Question: How would you handle it when your application will not work as specified without access to each of 30k images and you don't control when those images change? I'm do not want to have a crazy large SVN repository. Because I don't know when any of these images change, I really don't want them in my solution (definitely do not want a large solution, either). I also don't want a bunch of manual steps to do every time these images change. Our mantra, up to this point, has always been, any developer could download from SVN, compile and run our app. These images are going to kill that mantra. I'm tempted to make a WCF service that will return images if they exist and a dummy image if they don't. This way all dev boxes will return a dummy image and our build/staging/production boxes will return real images (ones that actually have the vendor's image installer installed on). This has to be a solved problem. What have other people done to handle these types of problems? I'm open to suggestions.

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  • ruby on rails basics help

    - by CHID
    Hi, i created a scaffolded application in rails by the name of product. The product_controller.rb file contains the following. class ProductsController ApplicationController def new @product = Product.new respond_to do |format| format.html # new.html.erb format.xml { render :xml = @product } end end def create @product = Product.new(params[:product]) respond_to do |format| if @product.save flash[:notice] = 'Product was successfully created.' format.html { redirect_to(@product) } format.xml { render :xml = @product, :status = :created, :location = @product } else format.html { render :action = "new" } format.xml { render :xml = @product.errors, :status = :unprocessable_entity } end end end Now when the url http://localhost:3000/products/create is given Where new product link is clicked, control is transferred to new definition in the controller class and then an instance variable @product is created. BUT WHERE IS THIS VARIABLE PASSED? The funtion inturn calls new.rhtml which contains <% form_for(@product) do |f| % #all form elments declaration <% f.submit "Create" % <%= end % Here @product is initialized in the controller file and passed to this new.rhtml. So where does form_for(@product) gets the data? How does the control gets tranfered to create function in controller file when submit button is clicked? No where action is specified to the controller file. in the create function, wat does redirec_to(@product) specify where @product is an object received from the new.html file... I am very much confused on the basics of ROR. Somone pls help me clarify this. pardon me for making such a big post. I have lots of doubts in this single piece of code

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  • Providing access to a no-www website in an active directory environment

    - by oasisbob
    Our website is hosted externally, off our network. The canonical URL is a is intentionally lacking www, and will 301 redirect any requests containing www to the canonical URL. So far, so good. The problem is providing access to the website from within our LAN. In theory, the answer is simple: add a host record in DNS pointing foobarco.org to the external webhost. (eg foobarco.org -- 203.0.113.7) However, Our active directory domain is the same as our public website (foobarco.org), and AD appears to periodically auto-create host (A) records in the domain root corresponding to our domain controllers. This causes obvious problems: users on the LAN attempting to access the website resolve the domain controllers instead. As a stop-gap measure we're overriding DNS using the hosts file on clients, but this is a quick hack that doesn't scale well. The hosts-file hack hasn't broken anything obvious, so I doubt that this behavior is essential to AD operations, but I haven't found a way to disable it. Is it possible to override this behavior?

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  • How do I find the highest level TR that contains a specific ID nested in a table

    - by Mykroft
    I have some HTML that looks like this (NOTE: I know this code isn't great but I didn't design it originally and some of it is auto generated): <table id="tab1"> <tr> <td><span>Some text</span></td> <td><span>more text</span></td> <td><input type="text" id="inp1" onclick="DoSomething(this);" /></td> </tr> <tr> <td><span>Some text</span></td> <td><span>more text</span></td> <td><table id="tab2"> <tr><td><input type="radio" id="inp2" onclick="DoSomething(this);" /><span>item</span></td></tr> </table></td> </tr> </table> All of that is embedded in a table which is also embedded in a table and so on. In the DoSomething(this) function I want to retrieve the TR underneath the table tab1. I'm having trouble figuring out the jquery necessary for this. Currently I'm doing something like this: function DoSomething(control) { var parentTab = '<%=tab1.ClientID %>'; var tr = $('#' + parentTab + ' > tbody > tr').has('#' + $(control).attr('id')).get(0); } This seems really messy but works. Is there a cleaner way to do this? If it helps the input inside the table will always be a radio button and a radio button will never appear outside of a sub table. Ideally I'd like to do this without having to know the id of tab1 but that seems impossible.

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  • Failed to create a 'System.Windows.RoutedEventHandler' from the text 'Button_Click'

    - by ay89
    In my windows phone 8 application, while trying to create a dependency property I am always getting this exception. what I am doing wrong, plz guide me. {System.Windows.Markup.XamlParseException: Failed to create a 'System.Windows.RoutedEventHandler' from the text 'Button_Click'. [Line: 108 Position: 66] at System.Windows.Application.LoadComponent(Object component, Uri resourceLocator) at com.sap.View.HomePage.InitializeComponent() at com.sap.View.HomePage..ctor()} this is code-behind of Header public static readonly DependencyProperty MenuClickProperty = DependencyProperty.Register("MenuClick", typeof(RoutedEventHandler), typeof(Header), new PropertyMetadata(OnMenuClickHandlerChanged)); public RoutedEventHandler MenuClick { get { return (RoutedEventHandler)GetValue(MenuClickProperty); } set { SetValue(MenuClickProperty, new RoutedEventHandler(value)); } } private static void OnMenuClickHandlerChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) { Header header = d as Header; header.OnMenuClickHandlerPropertyChanged(e); } private void OnMenuClickHandlerPropertyChanged(DependencyPropertyChangedEventArgs e) { MenuButton.Click += MenuClick; } this is in my user control (Header) <Button Click="{Binding Path=MenuClick, Source={RelativeSource Mode=Self}}" /> this is how i am including control on my Page: <myControls:Header Title="{Binding Title}" MenuClick="Button_Click" /> this is in code-behind: public void Button_Click(object sender, RoutedEventArgs e) { OpenSettings(); }

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  • How to create workspace in TFS

    - by kumar
    Hi, I followed this way. To create a workspace to manage your source-controlled files 1. From the File menu, select Source Control, and then click Workspaces. 2. In the Manage Workspaces dialog box, click Add. 3. Type a descriptive name in the Name box, enter a comment describing the new workspace in the Comment box, and provide alternative Owner and Computer name values, as necessary. 4. Under Working Folders, in the Source Control Folder box, click the text box and then the ellipsis (…). 5. In the Browse for Folder dialog box, select a server folder, and then click OK. 6. Under Working Folders, in the Local Folder box, click the text box, and then click the ellipsis (…). 7. In the Browse for Folder dialog box, select a folder on your computer, and then click OK. 8. In the Add Workspace dialog box, click OK to create the workspace. 9. In the Manage Workspaces dialog box, click Close. when I click OK button it should get all the folder from TFS to my Local machine? but its not doing that after clcking ok and Close nothing is happening and my local floder does not contain this files tooo? Thanks

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  • How important is the website logo on a page?

    - by meo
    I have stopped to insert "img" tags for the logo of the page. Because its not an image that is part of the content, its a design element but its still a information I want to have control over. So I just write the title in a "a" element as display: block, overflow: hidden and I push the text out with some padding. I think thats a good solution for SEO because you are keeping control of how important the logo should be on a page. But now my dilemma is starting. How important is the logo of a page? "A list apart" puts the logo in a h1 element. But is the logo really that important? On article pages you have two H1 elements (the logo and the title of the article) Most of the sites just use a img balbal /a, but I don't like this solution. Because I just want to use img for images that are part of the content... Its kinda philosophical question, I hope you can give me some input or some articles to read about that...

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  • Threading in Android

    - by virsir
    I am currently developing Android app, it needs download content from internet. I use thread to do that and then call runOnUiThread method to update GUI. I placed a refresh menu on it, if user tried to refresh the content, the download thread will be created and started. The problem is that how can I control the thread order, I need to accept the latest request's response and abandon previous thread requests if there were some other requests still running because the request parameters may have been changed by user. Currently I was using a threadId to do this thing, when a thread finished, it will check its threadId, if it was the latest recored one, it then takes control and render the response. My question is that is there any other proper better solution for this? Do I need to stop threads when user exit the app? I remember that some book said that do not try stop thread manually and wait itself finish is a good practice, is that true? Should I stop them by calling "stop" or "interrupt" method? I read some documents around threading in Android and found the class HandlerThread, what is it? In what kind of situation I need to use it?

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  • Applying powershell outside IT Management.

    - by Tormod
    Hi. We have a flexible process control system by which automation engineers configure up large application comprising thousands of small logical units that are parameterized and integrated into the control flow. There are many tasks that are repetitive on the granular level, and there are a multitude of proprietary productivity tools that have been made to meet this demand. We have different business segments, and the automation engineers vary across the board in skill sets and interests. Fancy GUI and usability versus flexibility is a common discussion. At first glance, powershell seems to be a sensible platform to implement such tooling and which also would be a advantageous cross-over skill to manage the IT aspects of the system setup and deployment as a whole. This should allow the script savvy their desired flexibility (they are already a scripting crowd) and the GUI dependant could still get their desired GUI underpinned by powershell. But I can't seem to find many people/groups who have tried to use the scriptability and object passing of powershell extensively to accommodate a heterogeneous user community outside the realm of IT management. Do anybody have any tips or word of caution? Am I missing something obvious as to why this shouldn't be done? Shouldn't powershell be taking over the world? ;-)

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  • Controlling race condition at startup.

    - by Will Hartung
    I have some code that I want to have some one time initialisation performed. But this code doesn't have a definite lifecycle, so my logic can be potentially invoked by multiple threads before my initialisation is done. So, I want to basically ensure that my logic code "waits" until initialisation is done. This is my first cut. public class MyClass { private static final AtomicBoolean initialised = new AtomicBoolean(false); public void initialise() { synchronized(initialised) { initStuff(); initialised.getAndSet(true); initialised.notifyAll(); } } public void doStuff() { synchronized(initialised) { if (!initialised.get()) { try { initialised.wait(); } catch (InterruptedException ex) { throw new RuntimeException("Uh oh!", ex); } } } doOtherStuff(); } } I basically want to make sure this is going to do what I think it's going to do -- block doStuff until the initialised is true, and that I'm not missing a race condition where doStuff might get stuck on a Object.wait() that will never arrive. Edit: I have no control over the threads. And I want to be able to control when all of the initialisation is done, which is why doStuff() can't call initialise(). I used an AtomicBoolean as it was a combination of a value holder, and an object I could synchronize. I could have also simply had a "public static final Object lock = new Object();" and a simple boolean flag. AtomicBoolean conveniently gave me both. A Boolean can not be modified. The CountDownLatch is exactly what I was looking for. I also considered using a Sempahore with 0 permits. But the CountDownLatch is perfect for just this task.

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  • Beginner MVC question - Correct approach to render out a List and details?

    - by fizzer
    I'm trying to set up a page where I display a list of items and the details of the selected item. I have it working but wonder whether I have followed the correct approach. I'll use customers as an example I have set the aspx page to inherit from an IEnumerable of Customers. This seems to be the standard approach to display the list of items. For the Details I have added a Customer user control which inherits from customer. I think i'm on the right track so far but I was a bit confused as to where I should store the id of the customer whose details I intend to display. I wanted to make the id optional in the controller action so that the page could be hit using "/customers" or "customers/1" so I made the arg optional and stored the id in the ViewData like this: public ActionResult Customers(string id = "0") { Models.DBContext db = new Models.DBContext(); var cList = db.Customers.OrderByDescending(c => c.CustomerNumber); if (id == "0") { ViewData["CustomerNumber"] = cList.First().CustomerNumber.ToString(); } else { ViewData["CustomerNumber"] = id; } return View("Customers", cList); } I then rendered the User control using RenderPartial in the front end: <%var CustomerList = from x in Model where x.CustomerNumber == Convert.ToInt32(ViewData["CustomerNumber"]) select x; Customer c = (Customer)CustomerList.First(); %> <% Html.RenderPartial("Customer",c); %> Then I just have an actionLink on each listed item: <%: Html.ActionLink("Select", "Customers", new { id = item.CustomerNumber })% It all seems to work but as MVC is new to me I would just be interested in others thoughts on whether this is a good approach?

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  • Where does Windows store MSI files for uninstallation?

    - by Nilzor
    I'm trying to figure out how Windows (XP through 7) is handling installation and uninstallation of MSI files. I have come up in situations where Windows Installer is unable to uninstall because it's missing the original MSI file, which leads me to believe that it stores a copy of all installed MSI packages somewhere. Where? I've had a couple of theories. It expectes it to reside in the same folder as it was installed from. The registry keys in HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall does point to the original installation folder, and error messages when the MSI file is missing often point to this. Removing the MSI file from this folder does not hinder the uninstallation process though, so I've refused this theory. C:\Windows\Installer. This folder actually contains a bunch of seemingly randomly named MSI files. But this list is incomplete. I do find entries in the registry key mentioned in 1) which does not have an MSI copy in this folder. So how does this work? How is windows installer able to uninstall MSI-installed applications even though the MSI is not in 1) and not in 2)?

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  • Domain model for an online WYSYWG webpage generator / runtime

    - by CharlieBrown
    Hi all, I'm using C#, MVC, NHibernate and StructureMap as my IoC container, and need some ideas regarding my domain model. The application I'm working has two parts: an Authoring part and a Runtime part. The idea is to allow the user to create a webpage in Authoring (mostly a form actually) by choosing from a set of predefined controls. That webpage will be later used as a form in a call center environment (Runtime part), or may be used in an intranet portal, etc. Basically something similar to what a CMS would do. The difference is, of course, that the webpage/form the author generates will be used and fulfilled in runtime, and that authros should be able to freely create the webpage they want without limitations. I have a draft working model that allows a RunController to iterate over the ScriptPage (my class for the "generated webpage") Controls collection and uses partial views to render each of them. Works kind of fine. Basically I have a common ScriptControl class, and then I can create for example a TextInputControl or a DropDownControl by inheriting from that base class. I can also figure out the Authoring part of the app, although that will surely be fun in itself for sure. :) The biggest problem I have now is persistance. In order to be flexible, I want to be able to add more controls, and template controls (think of an Address composite control) in sepparate DLLs, so I think having a relational model that handles very possible control is not the way to go. My current thinking is using a kind of ObjectStore: binary-serializing the ScriptPage object that contains the List collection and deserializing at Runtime, but I'm not sure how good will it work with NHibernate and how good the performance will be. Serializing a small "page" with 10 controls results in 7964 bytes, for example. Any ideas out there? Thanks in advance, excuse the length. ;)

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