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  • How can I set partial text color in JTextArea

    - by ComputerJy
    I want to set color for specific lines in the text area. What I've found so far, was the following // Declarations private final DefaultStyledDocument document; private final MutableAttributeSet homeAttributeSet; private final MutableAttributeSet awayAttributeSet; // Usage in the form constructor jTextAreaLog.setDocument(document); homeAttributeSet = new SimpleAttributeSet(); StyleConstants.setForeground(homeAttributeSet, Color.blue); StyleConstants.setItalic(homeAttributeSet, true); awayAttributeSet = new SimpleAttributeSet(); StyleConstants.setForeground(awayAttributeSet, Color.red); // Setting the style of the last line final int start = jTextAreaLog.getLineStartOffset(jTextAreaLog.getLineCount() - 2); final int length = jTextAreaLog.getLineEndOffset(jTextAreaLog.getLineCount() - 1) - start; document.setCharacterAttributes(start, length, awayAttributeSet, true); But this is not working. What am I doing wrong?

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  • Listing subdirectories 3 levels deep using LINQ C#

    - by paradox
    I'd like to know if there is a better alternative to my following code (preferably using LINQ) #region List and filter directories to only 3 levels deep // List all subdirectories within main directory string[] folders = Directory.GetDirectories(@"C:\pdftest\", "*" ,SearchOption.AllDirectories); List<string> subdirectories = new List<string>(); //Filter away all main directories, now we are left with subdirectories 3 levels deep for (int i = 0; i<folders.Length; i++) { int occurences = folders[i].Split('\\').Length-1; if (occurences==4) subdirectories.Add(folders[i]); } #endregion

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  • Android: Voice Recording and saving audio

    - by user1320912
    I am working on application that will record the voice of the user and save the file on the SD card and then allow the user to listen to the audio again. I am able to allow the user to record his voice using the RecognizerIntent, but I cant figure out how to save the audio file and allow the user to hear the audio. I would appreciate it if someone could help me out. I have displayed my code below: // Setting up the onClickListener for Audio Button attachVoice = (Button) findViewById(R.id.AttachVoice_questionandanswer); attachVoice.setOnClickListener(new OnClickListener() { public void onClick(View v) { Intent voiceIntent = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH); voiceIntent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL, RecognizerIntent.LANGUAGE_MODEL_FREE_FORM); voiceIntent.putExtra(RecognizerIntent.EXTRA_PROMPT, "Please Speak"); startActivityForResult(voiceIntent, VOICE_REQUEST); } }); protected void onActivityResult(int requestCode, int resultCode, Intent data) { if(requestCode == VOICE_REQUEST && resultCode == RESULT_OK){ }

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  • Using ClaimsPrincipalPermissionAttribute, how do I catch the SecurityException?

    - by Ryan Roark
    In my MVC application I have a Controller Action that Deletes a customer, which I'm applying Claims Based Authorization to using WIF. Problem: if someone doesn't have access they see an exception in the browser (complete with stacktrace), but I'd rather just redirect them. This works and allows me to redirect: public ActionResult Delete(int id) { try { ClaimsPrincipalPermission.CheckAccess("Customer", "Delete"); _supplier.Delete(id); return RedirectToAction("List"); } catch (SecurityException ex) { return RedirectToAction("NotAuthorized", "Account"); } } This works but throws a SecurityException I don't know how to catch (when the user is not authorized): [ClaimsPrincipalPermission(SecurityAction.Demand, Operation = "Delete", Resource = "Customer")] public ActionResult Delete(int id) { _supplier.Delete(id); return RedirectToAction("List"); } I'd like to use the declarative approach, but not sure how to handle unauthorized requests. Any suggestions?

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  • Passing Custom event arguments to timer_TICK event

    - by Nimesh
    I have class //Create GroupFieldArgs as an EventArgs public class GroupFieldArgs : EventArgs { private string groupName = string.Empty; private int aggregateValue = 0; //Get the fieldName public string GroupName { set { groupName = value; } get { return groupName; } } //Get the aggregate value public int AggregateValue { set { aggregateValue = value; } get { return aggregateValue; } } } I have another class that creates a event handler public class Groupby { public event EventHandler eh; } Finally I have Timer on my form that has Timer_TICK event. I want to pass GroupFieldArgs in Timer_TICK event. What is the best way to do it?

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  • treeview binding wpf cannot bind nested property in a class

    - by devnet247
    Hi all New to wpf and therefore struggling a bit. I am putting together a quick demo before we go for the full implementation I have a treeview on the left with Continent Country City structure when a user select the city it should populate some textboxes in a tabcontrol on the right hand side I made it sort of work but cannot make it work with composite objects. In a nutshell can you spot what is wrong with my zaml or code. Why is not binding to a my CityDetails.ClubsCount or CityDetails.PubsCount? What I am building is based on http://www.codeproject.com/KB/WPF/TreeViewWithViewModel.aspx Thanks a lot for any suggestions or reply DataModel public class City { public City(string cityName) { CityName = cityName; } public string CityName { get; set; } public string Population { get; set; } public string Area { get; set; } public CityDetails CityDetailsInfo { get; set; } } public class CityDetails { public CityDetails(int pubsCount,int clubsCount) { PubsCount = pubsCount; ClubsCount = clubsCount; } public int ClubsCount { get; set; } public int PubsCount { get; set; } } ViewModel public class CityViewModel : TreeViewItemViewModel { private City _city; private RelayCommand _testCommand; public CityViewModel(City city, CountryViewModel countryViewModel):base(countryViewModel,false) { _city = city; } public string CityName { get { return _city.CityName; } } public string Area { get { return _city.Area; } } public string Population { get { return _city.Population; } } public City City { get { return _city; } set { _city = value; } } public CityDetails CityDetailsInfo { get { return _city.CityDetailsInfo; } set { _city.CityDetailsInfo = value; } } } XAML <DockPanel> <DockPanel LastChildFill="True"> <Label DockPanel.Dock="top" Content="Title " HorizontalAlignment="Center"></Label> <StatusBar DockPanel.Dock="Bottom"> <StatusBarItem Content="Status Bar" ></StatusBarItem> </StatusBar> <Grid DockPanel.Dock="Top"> <Grid.ColumnDefinitions> <ColumnDefinition/> <ColumnDefinition Width="Auto"/> <ColumnDefinition Width="2*"/> </Grid.ColumnDefinitions> <TreeView Name="tree" ItemsSource="{Binding Continents}"> <TreeView.ItemContainerStyle> <Style TargetType="{x:Type TreeViewItem}"> <Setter Property="IsExpanded" Value="{Binding IsExpanded,Mode=TwoWay}"/> <Setter Property="IsSelected" Value="{Binding IsSelected,Mode=TwoWay}"/> <Setter Property="FontWeight" Value="Normal"/> <Style.Triggers> <Trigger Property="IsSelected" Value="True"> <Setter Property="FontWeight" Value="Bold"></Setter> </Trigger> </Style.Triggers> </Style> </TreeView.ItemContainerStyle> <TreeView.Resources> <HierarchicalDataTemplate DataType="{x:Type ViewModels:ContinentViewModel}" ItemsSource="{Binding Children}"> <StackPanel Orientation="Horizontal"> <Image Width="16" Height="16" Margin="3,0" Source="Images\Continent.png"/> <TextBlock Text="{Binding ContinentName}"/> </StackPanel> </HierarchicalDataTemplate> <HierarchicalDataTemplate DataType="{x:Type ViewModels:CountryViewModel}" ItemsSource="{Binding Children}"> <StackPanel Orientation="Horizontal"> <Image Width="16" Height="16" Margin="3,0" Source="Images\Country.png"/> <TextBlock Text="{Binding CountryName}"/> </StackPanel> </HierarchicalDataTemplate> <DataTemplate DataType="{x:Type ViewModels:CityViewModel}" > <StackPanel Orientation="Horizontal"> <Image Width="16" Height="16" Margin="3,0" Source="Images\City.png"/> <TextBlock Text="{Binding CityName}"/> </StackPanel> </DataTemplate> </TreeView.Resources> </TreeView> <GridSplitter Grid.Row="0" Grid.Column="1" Background="LightGray" Width="5" HorizontalAlignment="Stretch" VerticalAlignment="Stretch"/> <Grid Grid.Column="2" Margin="5" > <TabControl> <TabItem Header="Details" DataContext="{Binding Path=SelectedItem.City, ElementName=tree, Mode=OneWay}"> <StackPanel > <TextBlock VerticalAlignment="Center" FontSize="12" Text="{Binding CityName}"/> <TextBlock VerticalAlignment="Center" FontSize="12" Text="{Binding Area}"/> <TextBlock VerticalAlignment="Center" FontSize="12" Text="{Binding Population}"/> <!-- DONT WORK WHY--> <TextBlock VerticalAlignment="Center" FontSize="12" Text="{Binding SelectedItem.CityDetailsInfo.ClubsCount}"/> <TextBlock VerticalAlignment="Center" FontSize="12" Text="{Binding SelectedItem.CityDetailsInfo.PubsCount}"/> </StackPanel> </TabItem> </TabControl> </Grid> </Grid> </DockPanel> </DockPanel>

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  • Why does this thumbnail generation code throw OutOfMemoryException on large files?

    - by tsilb
    This code works great for generating thumbnails, but when given a very large (100MB+) TIFF file, it throws OutOfMemoryExceptions. When I do it manually in Paint.NET on the same machine, it works fine. How can I improve this code to stop throwing on very large files? In this case I'm loading a 721MB TIF on a machine with 8GB RAM. The Task Manager shows 2GB used so something is preventing it from using all that memory. Specifically it throws when I load the Image to calculate the size of the original. What gives? /// <summary>Creates a thumbnail of a given image.</summary> /// <param name="inFile">Fully qualified path to file to create a thumbnail of</param> /// <param name="outFile">Fully qualified path to created thumbnail</param> /// <param name="x">Width of thumbnail</param> /// <returns>flag; result = is success</returns> public static bool CreateThumbnail(string inFile, string outFile, int x) { // Validation - assume 16x16 icon is smallest useful size. Smaller than that is just not going to do us any good anyway. I consider that an "Exceptional" case. if (string.IsNullOrEmpty(inFile)) throw new ArgumentNullException("inFile"); if (string.IsNullOrEmpty(outFile)) throw new ArgumentNullException("outFile"); if (x < 16) throw new ArgumentOutOfRangeException("x"); if (!File.Exists(inFile)) throw new ArgumentOutOfRangeException("inFile", "File does not exist: " + inFile); // Mathematically determine Y dimension int y; using (Image img = Image.FromFile(inFile)) { // OutOfMemoryException double xyRatio = (double)x / (double)img.Width; y = (int)((double)img.Height * xyRatio); } // All this crap could have easily been Image.Save(filename, x, y)... but nooooo.... using (Bitmap bmp = new Bitmap(inFile)) using (Bitmap thumb = new Bitmap((Image)bmp, new Size(x, y))) using (Graphics g = Graphics.FromImage(thumb)) { g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality; g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High; g.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality; System.Drawing.Imaging.ImageCodecInfo codec = System.Drawing.Imaging.ImageCodecInfo.GetImageEncoders()[1]; System.Drawing.Imaging.EncoderParameters ep2 = new System.Drawing.Imaging.EncoderParameters(1); ep2.Param[0] = new System.Drawing.Imaging.EncoderParameter(System.Drawing.Imaging.Encoder.Quality, 100L); g.DrawImage(bmp, new Rectangle(0,0,thumb.Width, thumb.Height)); try { thumb.Save(outFile, codec, ep2); return true; } catch { return false; } } }

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  • How can I use Web Services Core to send a complex type as a parameter to a SOAP API method

    - by Matthew Brindley
    I don't do much Cocoa programming, so I'm probably missing something obvious, so please excuse the basic question. I have a SOAP method that expects a complex type as a paramater. Here's some WSDL: <s:element name="SaveTestResult"> <s:complexType> <s:sequence> <s:element minOccurs="0" maxOccurs="1" name="result" type="tns:TestItemResponse" /> </s:sequence> </s:complexType> </s:element> Here's the definition of the complex type "TestItemResponse": <s:complexType name="TestItemResponse"> <s:sequence> <s:element minOccurs="1" maxOccurs="1" name="TestItemRequestId" type="s:int" /> <s:element minOccurs="1" maxOccurs="1" name="ExternalId" type="s:int" /> <s:element minOccurs="0" maxOccurs="1" name="ApiId" type="s:string" /> <s:element minOccurs="0" maxOccurs="1" name="InboxGuid" type="s:string" /> <s:element minOccurs="0" maxOccurs="1" name="SpamResult" type="tns:SpamResult" /> <s:element minOccurs="0" maxOccurs="1" name="ResultImageSet" type="tns:ResultImageSet" /> <s:element minOccurs="1" maxOccurs="1" name="ExclusiveUseMailAccountId" type="s:int" /> <s:element minOccurs="1" maxOccurs="1" name="State" type="tns:TestItemResponseState" /> <s:element minOccurs="0" maxOccurs="1" name="ErrorShortDescription" type="s:string" /> <s:element minOccurs="0" maxOccurs="1" name="ErrorFullDescription" type="s:string" /> </s:sequence> </s:complexType> I've been using Web Services Core to call a SOAP API method that requires a simple string param, that works great. That same method returns a complex type which WSC converted into nested NSDictionaries, so no problems there. So I assumed I'd be able to convert my local TestItemResponse class into an NSDictionary and then use that as the complex type param. It almost worked, but unfortunately WSC set the object's type as "Dictionary", instead of "TestItemResponse", and the server complained. <TestItemResponse xsi:type=\"SOAP-ENC:Dictionary\"> <ErrorFullDescription xsi:type=\"xsd:string\">foo</ErrorFullDescription> ... I can't seem to find anything that allows you to override the type WSC assigns to the element in the SOAP XML. I've been using code adapted from here, I'm happy to list it, it's just quite long and this is already the longest SO question I've ever posted.

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  • Can't make an array in C#

    - by Josh
    I'm trying to make a dynamic array in C# but I get an annoying error message. Here's my code: private void Form1_Load(object sender, EventArgs e) { int[] dataArray; Random random = new Random(); for (int i = 0; i < random.Next(1, 10); i++) { dataArray[i] = random.Next(1, 1000); } } And the error: Use of unassigned local variable 'dataArray' This is just baffling my mind. I came from VB, so please me gentle, lol. Cheers.

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  • Does "Debug" invalidate ASP.Net MVC OutputCache?

    - by William Edmondson
    I have images stored in a database and am serving them from an MVC controller as "FileResult". If I run the MVC application from Visual Studio 2008 in debug mode and set a break point inside the controller method the debugger intercepts the call on every page refresh regardless of my "OutputCache" settings. Does the VS debugger invalidate the OutputCache or is there something else going on here? [OutputCache(Duration = 86400, VaryByParam = "id")] public FileResult Index(string id) { byte[] image; int imageId; int.TryParse(id, out imageId); using (var ctx = new EPEntities()) { var imageObj = (from images in ctx.Images where images.ID == imageId select images).FirstOrDefault(); image = imageObj.Image; } return new FileContentResult(image, "image/gif"); }

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  • How to set initial window size in Java OpenGL

    - by tommy-susanto
    Hi guys... I just built a Java OpenGL application in Eclipse... and when i was trying to export the application using EclipseP5Exporter, it requires me to initialize the window size (not viewport size, a window may contain several viewports). I already googled some solutions in the net but I can't seem to get anything useful.. I've tried the method : "glutInitWindowSize(int width, int height);" but it seems to work only in C and python openGL. even if i append the glut before the method (glut.glutInitWindowSize()) eclipse doesn't recognize that method.. So if you guys have any suggestions please let me know... Thank you....

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  • Fields of class, are they stored in the stack or heap?

    - by Mirek
    I saw a question yesterday which raised (for me) another question. Please look at the following code: public class Class1 { int A; //as I uderstand, int is value type and therefore lives in the stack } class Class2 { Run() { Class1 instance1 = new Class1(); instance1.A = 10; //it points to value type, but isnt this reference (on heap)? } } Or while creating the instance of Class1, its field types are created on the heap as well? But then I do not understand when it would really be on the stack as almost always you need to create an instance of object in order to use it fields.

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  • NSStringWithFormat Swizzled to allow missing format numbered args

    - by coneybeare
    Based on this SO question asked a few hours ago, I have decided to implement a swizzled method that will allow me to take a formatted NSString as the format arg into stringWithFormat, and have it not break when omitting one of the numbered arg references (%1$@, %2$@) I have it working, but this is the first copy, and seeing as this method is going to be potentially called hundreds of thousands of times per app run, I need to bounce this off of some experts to see if this method has any red flags, major performance hits, or optimizations #define NUMARGS(...) (sizeof((int[]){__VA_ARGS__})/sizeof(int)) @implementation NSString (UAFormatOmissions) + (id)uaStringWithFormat:(NSString *)format, ... { if (format != nil) { va_list args; va_start(args, format); // $@ is an ordered variable (%1$@, %2$@...) if ([format rangeOfString:@"$@"].location == NSNotFound) { //call apples method NSString *s = [[[NSString alloc] initWithFormat:format arguments:args] autorelease]; va_end(args); return s; } NSMutableArray *newArgs = (NSMutableArray *)[NSMutableArray arrayWithCapacity:NUMARGS(args)]; id arg = nil; int i = 1; while (arg = va_arg(args, id)) { NSString *f = (NSString *)[NSString stringWithFormat:@"%%%d\$\@", i]; i++; if ([format rangeOfString:f].location == NSNotFound) continue; else [newArgs addObject:arg]; } va_end(args); char *newArgList = (char *)malloc(sizeof(id) * [newArgs count]); [newArgs getObjects:(id *)newArgList]; NSString* result = [[[NSString alloc] initWithFormat:format arguments:newArgList] autorelease]; free(newArgList); return result; } return nil; } The basic algorithm is: search the format string for the %1$@, %2$@ variables by searching for %@ if not found, call the normal stringWithFormat and return else, loop over the args if the format has a position variable (%i$@) for position i, add the arg to the new arg array else, don't add the arg take the new arg array, convert it back into a va_list, and call initWithFormat:arguments: to get the correct string. The idea is that I would run all [NSString stringWithFormat:] calls through this method instead. This might seem unnecessary to many, but click on to the referenced SO question (first line) to see examples of why I need to do this. Ideas? Thoughts? Better implementations? Better Solutions?

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  • C++ linking issue on Visual Studio 2008 when crosslinking different projects on same solution

    - by Luís Guilherme
    I'm using Google Test Framework to set some unit tests. I have got three projects in my solution: FN (my project) FN_test (my tests) gtest (Google Test Framework) I set FN_test to have FN and gtest as references (dependencies), and then I think I'm ready to set up my tests (I've already set everyone to /MTd (not doing this was leading me to linking errors before)). Particularly, I define a class called Embark in FN I would like to test using FN_test. So far, so good. Thus I write a classe called EmbarkTest using googletest, declare a member Embark* and write inside the constructor: EmbarkTest() { e = new Embark(900,2010); } Then , F7 pressed, I get the following: 1>FN_test.obj : error LNK2019: unresolved external symbol "public: __thiscall Embark::Embark(int,int)" (??0Embark@@QAE@HH@Z) referenced in function "protected: __thiscall EmbarkTest::EmbarkTest(void)" (??0EmbarkTest@@IAE@XZ) 1>D:\Users\lg\Product\code\FN\Debug\FN_test.exe : fatal error LNK1120: 1 unresolved externals Does someone know what have I done wrong and/or what can I do to settle this?

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  • Why touching "d_name" makes calls to readdir() fail?

    - by Sarah Mani
    Hi, I'm trying to write a little helper for Windows which eventually will accept a file extension as an argument and return the number of files of that kind in the current directory. To do so, I'm reading the file entries in the directories and after getting the extension I'd like to convert it to lowercase to compare it with the yet-to-add specified argument. When converting the extension to lowercase I found that touching even a duplicate string of the d_name variable will cause a strange behaviour, like no more calls to readdir are called. Here is the code I'm using right now (the commented code is preliminary) and outputs for a given directory: #include <ctype.h> #include <dirent.h> #include <stdio.h> #include <string.h> char * strrch(char *string, size_t elements, char character) { char *reverse = string + elements; while (--reverse != string) if (*reverse == character) return reverse; return NULL; } void test(char *string) { // Even being a duplicate will make it fail: char *str = strdup(string); printf("Strings: %s %s\n", string, str); *str = 'a'; printf("Strings: %s %s\n", string, str); //unsigned short int i = 0; //for (; str[i] != '\0', str++; i++) // str[i] = tolower((unsigned char) str[i]); //puts(str); } int main(int argc, char **argv) { DIR *directory; struct dirent *element; if (directory = opendir(".")) { while (element = readdir(directory)) test(strrch(element->d_name, element->d_namlen, '.')); closedir(directory); puts(NULL); } else puts("Couldn't open the directory.\n"); } Output without modifying the duplicate (modification and the second printf call commented): Strings: (null) (null) Strings: . . Strings: .exe .exe Strings: .pdf .pdf Strings: .c .c Strings: .ini .ini Strings: .pdf .pdf Strings: .pdf .pdf Strings: .pdf .pdf Strings: .flac .flac Strings: .FLAC .FLAC Strings: .lnk .lnk Strings: .URL .URL Output of the same directory (with the code above, with the 2 printfs): Strings: (null) (null) Is there anything wrong? Is it a compiler issue? I'm using GCC 4.4.3 in Windows (MinGW) right now. Thank you very much for your help. By the way, is there any other way to work with files and directories in a Windows environment not using the POSIX functions?

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  • Csharp component which generates fragments with highlights for diffs for 2 strings

    - by MicMit
    I need C# implementation ( ideally open source ) which is similar to Delphi DLL. I am currently using the wrapper ( C# syntax is provided , but it is a call from a different language ) zdiff( string ref str1, string ref str2, int range , int trim ) it calls inside str1 = GetHiDiff(@str1,1,trim) str2 = GetHiDiff(@str1,2,trim) where function GetHiDiff(s:pchar; sIndex:integer; wtrim:integer): pchar; stdcall; What it does it returns a left fragment html of str1 and a right html fragment of str2 with diffs highlighted as strings are passed by reference. Range parameter determines the size of html fragment. Not sure what trim 0 does.

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  • Is this good code? Linked List Stack Implementation

    - by Quik Tester
    I have used the following code for a stack implementation. The top keeps track of the topmost node of the stack. Now since top is a data member of the node function, each node created will have a top member, which ideally we wouldn't want. Firstly, is this good approach to coding? Secondly, will making top as static make it a better coding practice? Or should I have a global declaration of top? #include<iostream> using namespace std; class node { int data; node *top; node *link; public: node() { top=NULL; link=NULL; } void push(int x) { node *n=new node; n->data=x; n->link=top; top=n; cout<<"Pushed "<<n->data<<endl; } void pop() { node *n=new node; n=top; top=top->link; n->link=NULL; cout<<"Popped "<<n->data<<endl; delete n; } void print() { node *n=new node; n=top; while(n!=NULL) { cout<<n->data<<endl; n=n->link; } delete n; } }; int main() { node stack; stack.push(5); stack.push(7); stack.push(9); stack.pop(); stack.print(); } Any other suggestions welcome. I have also seen codes where there are two classes, where the second one has the top member. What about this? Thanks. :)

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  • Are primitive types garbage collected in Android?

    - by snctln
    I know this may be a dumb question, but my background is more in c++ and managing my own memory. I am currently cutting down every single allocation that I can from one of my games to try and reduce the frequency of garbage collection and perceived "lag", so for every variable that I create that is an Object (String and Rect for example) I am making sure that I create it before hand in my constructor and not create temporary variables in simple 10 line functions... (I hope that makes sense) Anyways I was working though it some more tonight and I realized that I may be completely wrong about my assumption on garbage collection and primitive types (int, boolean, float) are these primitive type variables that I create in a 10 line function that gets called 20 times a second adding to my problem of garbage collection? So a year ago every few seconds I would see a message in logcat like GC freed 4010 objects / 484064 bytes in 101ms Now I see that message every 15-90 seconds or so... So to rephrase my question: Are primitive types (int, float, boolean, etc) included when seeing this message?

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  • WPF: Timers

    - by Ilya Verbitskiy
    I believe, once your WPF application will need to execute something periodically, and today I would like to discuss how to do that. There are two possible solutions. You can use classical System.Threading.Timer class or System.Windows.Threading.DispatcherTimer class, which is the part of WPF. I have created an application to show you how to use the API.     Let’s take a look how you can implement timer using System.Threading.Timer class. First of all, it has to be initialized.   1: private Timer timer; 2:   3: public MainWindow() 4: { 5: // Form initialization code 6: 7: timer = new Timer(OnTimer, null, Timeout.InfiniteTimeSpan, Timeout.InfiniteTimeSpan); 8: }   Timer’s constructor accepts four parameters. The first one is the callback method which is executed when timer ticks. I will show it to you soon. The second parameter is a state which is passed to the callback. It is null because there is nothing to pass this time. The third parameter is the amount of time to delay before the callback parameter invokes its methods. I use System.Threading.Timeout helper class to represent infinite timeout which simply means the timer is not going to start at the moment. And the final fourth parameter represents the time interval between invocations of the methods referenced by callback. Infinite timeout timespan means the callback method will be executed just once. Well, the timer has been created. Let’s take a look how you can start the timer.   1: private void StartTimer(object sender, RoutedEventArgs e) 2: { 3: timer.Change(TimeSpan.Zero, new TimeSpan(0, 0, 1)); 4:   5: // Disable the start buttons and enable the reset button. 6: }   The timer is started by calling its Change method. It accepts two arguments: the amount of time to delay before the invoking the callback method and the time interval between invocations of the callback. TimeSpan.Zero means we start the timer immediately and TimeSpan(0, 0, 1) tells the timer to tick every second. There is one method hasn’t been shown yet. This is the callback method OnTimer which does a simple task: it shows current time in the center of the screen. Unfortunately you cannot simple write something like this:   1: clock.Content = DateTime.Now.ToString("hh:mm:ss");   The reason is Timer runs callback method on a separate thread, and it is not possible to access GUI controls from a non-GUI thread. You can avoid the problem using System.Windows.Threading.Dispatcher class.   1: private void OnTimer(object state) 2: { 3: Dispatcher.Invoke(() => ShowTime()); 4: } 5:   6: private void ShowTime() 7: { 8: clock.Content = DateTime.Now.ToString("hh:mm:ss"); 9: }   You can build similar application using System.Windows.Threading.DispatcherTimer class. The class represents a timer which is integrated into the Dispatcher queue. It means that your callback method is executed on GUI thread and you can write a code which updates your GUI components directly.   1: private DispatcherTimer dispatcherTimer; 2:   3: public MainWindow() 4: { 5: // Form initialization code 6:   7: dispatcherTimer = new DispatcherTimer { Interval = new TimeSpan(0, 0, 1) }; 8: dispatcherTimer.Tick += OnDispatcherTimer; 9: } Dispatcher timer has nicer and cleaner API. All you need is to specify tick interval and Tick event handler. The you just call Start method to start the timer.   private void StartDispatcher(object sender, RoutedEventArgs e) { dispatcherTimer.Start(); // Disable the start buttons and enable the reset button. } And, since the Tick event handler is executed on GUI thread, the code which sets the actual time is straightforward.   1: private void OnDispatcherTimer(object sender, EventArgs e) 2: { 3: ShowTime(); 4: } We’re almost done. Let’s take a look how to stop the timers. It is easy with the Dispatcher Timer.   1: dispatcherTimer.Stop(); And slightly more complicated with the Timer. You should use Change method again.   1: timer.Change(Timeout.InfiniteTimeSpan, Timeout.InfiniteTimeSpan); What is the best way to add timer into an application? The Dispatcher Timer has simple interface, but its advantages are disadvantages at the same time. You should not use it if your Tick event handler executes time-consuming operations. It freezes your window which it is executing the event handler method. You should think about using System.Threading.Timer in this case. The code is available on GitHub.

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  • Why / When / How is this Android serviceBinder resetting to null?

    - by GaZ
    I've written a ListActivity for Android 2.1 which is used to display a list of event categories. As the user selects a category, the program calls a web service to retrieve a list of sub-events. For example, a top level event might be "soccer" and when the user selects this the web service would return various soccer associations (e.g. "english", "french", "german", etc.) and display them in a new list. The following code seems to work occasionally, however sometimes the call to the service (in EventsListTask) fails because the serviceBinder is null. How/Why does this happen? public class EventListsActivity extends ListActivity { private static final String EVENT_ID = "EventId"; private List<ListItem> eventList; private ArrayAdapter<ListItem> listItemArrayAdapter; private static final int LOADING_DIALOG = 1; private EventsListTask eventsListTask = null; private BFService serviceBinder; private ServiceConnection mConnection = new ServiceConnection() { public void onServiceConnected(ComponentName componentName, IBinder iBinder) { Log.i("EventListsActivity", "service connected"); serviceBinder = ((BFService.BFBinder)iBinder).getService(); } public void onServiceDisconnected(ComponentName componentName) { Log.i("EventListsActivity", "service disconnected"); serviceBinder = null; } }; @Override public void onCreate(Bundle savedInstanceState) { Log.i("EventListsActivity", "onCreate"); super.onCreate(savedInstanceState); setContentView(R.layout.list); eventList = new ArrayList<ListItem>(); listItemArrayAdapter = new ArrayAdapter<ListItem>(this, R.layout.row, eventList); setListAdapter(listItemArrayAdapter); Intent bindIntent = new Intent(this, BFService.class); bindService(bindIntent, mConnection, Context.BIND_AUTO_CREATE); int eventId = getIntent().getIntExtra(EVENT_ID, -1); if (eventsListTask == null || eventsListTask.getStatus() == AsyncTask.Status.FINISHED) { eventsListTask = new EventsListTask(); eventsListTask.execute(eventId); } } @Override protected void onDestroy() { Log.i("EventListsActivity", "destroyed"); super.onDestroy(); unbindService(mConnection); } @Override protected void onListItemClick(ListView listView, View view, int position, long id) { super.onListItemClick(listView, view, position, id); ListItem selectedItem = (ListItem) listView.getAdapter().getItem(position); Intent intent; if (selectedItem.getMarketType() != null) { intent = new Intent(this, MarketActivity.class); intent.putExtra(EVENT_ID, selectedItem.getId()); startActivityIfNeeded(intent, -1); } else if (selectedItem.getId() != -1) { intent = new Intent(this, EventListsActivity.class); intent.putExtra(EVENT_ID, selectedItem.getId()); startActivityIfNeeded(intent, -1); } else { Log.e("EventListsActivity", "unexpected item selected!"); } } @Override protected Dialog onCreateDialog(int id) { switch (id) { case (LOADING_DIALOG) : AlertDialog.Builder loadingDialog = new AlertDialog.Builder(this); loadingDialog.setTitle("Please Wait..."); loadingDialog.setMessage("Communicating with remote service."); return loadingDialog.create(); } return null; } private class EventsListTask extends AsyncTask<Integer, Void, LoginStatusEnum> { @Override protected void onPreExecute() { showDialog(LOADING_DIALOG); } @Override protected void onPostExecute(LoginStatusEnum loginStatusEnum) { dismissDialog(LOADING_DIALOG); if (loginStatusEnum != null) { switch (loginStatusEnum) { case OK: for (ListItem item : eventList) { listItemArrayAdapter.add(item); } listItemArrayAdapter.notifyDataSetChanged(); break; } } } @Override protected LoginStatusEnum doInBackground(Integer... params) { LoginStatusEnum result = LoginStatusEnum.OK; Integer eventId = params[0]; if (serviceBinder != null) { try { if (eventId == null || eventId == -1) { eventList = serviceBinder.getActiveEventTypes(); } else { eventList = serviceBinder.getEvents(eventId); } } catch (WebServiceException wse) { result = LoginStatusEnum.valueOf(wse.getMessage()); } } else { Log.e("EventListsActivity", "serviceBinder is null!"); } return result; } } } EDIT: The serviceBinder appears to be set to null when I reach the bottom of a list, when I change the target intent to go to a different activity: intent = new Intent(this, MarketActivity.class); intent.putExtra(EVENT_ID, selectedItem.getId()); startActivity(intent); This new activity also uses the same background service (binds in the same way, etc.). Is there anything I need to watch out for when doing this? Am I calling the target intent incorrectly? EDIT2: Here's the output from LogCat when I start the activity which calls the service (this time the service failed straight away!): 04-02 07:02:49.147: INFO/ActivityManager(61): Starting activity: Intent { cmp=net.foobar.activity/.EventListsActivity } 04-02 07:02:49.257: INFO/EventListsActivity(353): onCreate 04-02 07:02:49.426: INFO/EventListsActivity(353): service connected 04-02 07:02:49.437: ERROR/EventListsActivity(353): serviceBinder is null!

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  • LSP packet modify

    - by kellogs
    Hello, anybody care to share some insights on how to use LSP for packet modifying ? I am using the non IFS subtype and I can see how (pseudo?) packets first enter WSPRecv. But how do I modify them ? My inquiry is about one single HTTP response that causes WSPRecv to be called 3 times :((. I need to modify several parts of this response, but since it comes in 3 slices, it is pretty hard to modify it accordingly. And, maybe on other machines or under different conditions (such as high traffic) there would only be one sole WSPRecv call, or maybe 10 calls. What is the best way to work arround this (please no NDIS :D), and how to properly change the buffer (lpBuffers-buf) by increasing it ? int WSPAPI WSPRecv( SOCKET s, LPWSABUF lpBuffers, DWORD dwBufferCount, LPDWORD lpNumberOfBytesRecvd, LPDWORD lpFlags, LPWSAOVERLAPPED lpOverlapped, LPWSAOVERLAPPED_COMPLETION_ROUTINE lpCompletionRoutine, LPWSATHREADID lpThreadId, LPINT lpErrno ) { LPWSAOVERLAPPEDPLUS ProviderOverlapped = NULL; SOCK_INFO *SocketContext = NULL; int ret = SOCKET_ERROR; *lpErrno = NO_ERROR; // // Find our provider socket corresponding to this one // SocketContext = FindAndRefSocketContext(s, lpErrno); if ( NULL == SocketContext ) { dbgprint( "WSPRecv: FindAndRefSocketContext failed!" ); goto cleanup; } // // Check for overlapped I/O // if ( NULL != lpOverlapped ) { /*bla bla .. not interesting in my case*/ } else { ASSERT( SocketContext->Provider->NextProcTable.lpWSPRecv ); SetBlockingProvider(SocketContext->Provider); ret = SocketContext->Provider->NextProcTable.lpWSPRecv( SocketContext->ProviderSocket, lpBuffers, dwBufferCount, lpNumberOfBytesRecvd, lpFlags, lpOverlapped, lpCompletionRoutine, lpThreadId, lpErrno); SetBlockingProvider(NULL); //is this the place to modify packet length and contents ? if (strstr(lpBuffers->buf, "var mapObj = null;")) { int nLen = strlen(lpBuffers->buf) + 200; /*CHAR *szNewBuf = new CHAR[]; CHAR *pIndex; pIndex = strstr(lpBuffers->buf, "var mapObj = null;"); nLen = strlen(strncpy(szNewBuf, lpBuffers->buf, (pIndex - lpBuffers->buf) * sizeof (CHAR))); nLen = strlen(strncpy(szNewBuf + nLen * sizeof(CHAR), "var com = null;\r\n", 17 * sizeof(CHAR))); pIndex += 18 * sizeof(CHAR); nLen = strlen(strncpy(szNewBuf + nLen * sizeof(CHAR), pIndex, 1330 * sizeof (CHAR))); nLen = strlen(strncpy(szNewBuf + nLen * sizeof(CHAR), "if (com == null)\r\n" \ "com = new ActiveXObject(\"InterCommJS.Gateway\");\r\n" \ "com.lat = latitude;\r\n" \ "com.lon = longitude;\r\n}", 111 * sizeof (CHAR))); pIndex = strstr(szNewBuf, "Content-Length:"); pIndex += 16 * sizeof(CHAR); strncpy(pIndex, "1465", 4 * sizeof(CHAR)); lpBuffers->buf = szNewBuf; lpBuffers->len += 128;*/ } if ( SOCKET_ERROR != ret ) { SocketContext->BytesRecv += *lpNumberOfBytesRecvd; } } cleanup: if ( NULL != SocketContext ) DerefSocketContext( SocketContext, lpErrno ); return ret; } Thank you

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  • Why is FxCop warning about an overflow (CA2233) in this C# code?

    - by matt
    I have the following function to get an int from a high-byte and a low-byte: public static int FromBytes(byte high, byte low) { return high * (byte.MaxValue + 1) + low; } When I analyze the assembly with FxCop, I get the following critical warning: CA2233: OperationsShouldNotOverflow Arithmetic operations should not be done without first validating the operands to prevent overflow. I can't see how this could possibly overflow, so I am just assuming FxCop is being overzealous. Am I missing something? And what steps could be taken to correct what I have (or at least make the FxCop warning go away!)?

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  • HOM with Objective C

    - by Coxer
    Hey, i am new to objective C, but i tried to use HOM in order to iterate over an NSArray and append a string to each element. here is my code: void print( NSArray *array ) { NSEnumerator *enumerator = [array objectEnumerator]; id obj; while ( nil!=(obj = [enumerator nextObject]) ) { printf( "%s\n", [[obj description] cString] ); } } int main( int argc, const char *argv[] ) { NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init]; NSArray *names = [[NSArray alloc] init]; NSArray *names_concat = [[NSArray alloc] init]; names = [NSArray arrayWithObjects:@"John",@"Mary",@"Bob",nil]; names_concat = [[names collect] stringByAppendingString: @" Doe"]; print(names_concat); [pool release]; } What is wrong with this code? My compiler (gcc) says NSArray may not respond to "-collect"

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  • OpenGL Motion blur with the accumulation buffer in WxWidgets

    - by Klaus
    Hello, I'm trying to achieve a motion blur effect in my OpenGL application. I read somewhere this solution, using the accumulation buffer: glAccum(GL_MULT, 0.90); glAccum(GL_ACCUM, 0.10); glAccum(GL_RETURN, 1.0); glFlush(); at the end of the render loop. But nothing happens... What am I missing ? Additions after genpfault answer: Indeed I did not asked for an accumulation buffer when I initialized my context. So I tried to pass an array of attributes to the constructor of my wxGLCanvas, as described here: http://docs.wxwidgets.org/2.6/wx_wxglcanvas.html : int attribList[]={ WX_GL_RGBA , WX_GL_DOUBLEBUFFER , WX_GL_MIN_ACCUM_RED, WX_GL_MIN_ACCUM_GREEN, WX_GL_MIN_ACCUM_BLUE, 0} But all I get is a friendly Seg fault. Does someone understand how to use this ? (no problems with int attribList[]={ WX_GL_RGBA , WX_GL_DOUBLEBUFFER , 0})

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  • ubuntu: sem_timedwait not waking (C)

    - by gillez
    I have 3 processes which need to be synchronized. Process one does something then wakes process two and sleeps, which does something then wakes process three and sleeps, which does something and wakes process one and sleeps. The whole loop is timed to run around 25hz (caused by an external sync into process one before it triggers process two in my "real" application). I use sem_post to trigger (wake) each process, and sem_timedwait() to wait for the trigger. This all works successfully for several hours. However at some random time (usually after somewhere between two and four hours), one of the processes starts timing out in sem_timedwait(), even though I am sure the semaphore is being triggered with sem_post(). To prove this I even use sem_getvalue() immediately after the timeout, and the value is 1, so the timedwait should have been triggered. Please see following code: #include <stdio.h> #include <time.h> #include <string.h> #include <errno.h> #include <semaphore.h> sem_t trigger_sem1, trigger_sem2, trigger_sem3; // The main thread process. Called three times with a different num arg - 1, 2 or 3. void *thread(void *arg) { int num = (int) arg; sem_t *wait, *trigger; int val, retval; struct timespec ts; struct timeval tv; switch (num) { case 1: wait = &trigger_sem1; trigger = &trigger_sem2; break; case 2: wait = &trigger_sem2; trigger = &trigger_sem3; break; case 3: wait = &trigger_sem3; trigger = &trigger_sem1; break; } while (1) { // The first thread delays by 40ms to time the whole loop. // This is an external sync in the real app. if (num == 1) usleep(40000); // print sem value before we wait. If this is 1, sem_timedwait() will // return immediately, otherwise it will block until sem_post() is called on this sem. sem_getvalue(wait, &val); printf("sem%d wait sync sem%d. val before %d\n", num, num, val); // get current time and add half a second for timeout. gettimeofday(&tv, NULL); ts.tv_sec = tv.tv_sec; ts.tv_nsec = (tv.tv_usec + 500000); // add half a second if (ts.tv_nsec > 1000000) { ts.tv_sec++; ts.tv_nsec -= 1000000; } ts.tv_nsec *= 1000; /* convert to nanosecs */ retval = sem_timedwait(wait, &ts); if (retval == -1) { // timed out. Print value of sem now. This should be 0, otherwise sem_timedwait // would have woken before timeout (unless the sem_post happened between the // timeout and this call to sem_getvalue). sem_getvalue(wait, &val); printf("!!!!!! sem%d sem_timedwait failed: %s, val now %d\n", num, strerror(errno), val); } else printf("sem%d wakeup.\n", num); // get value of semaphore to trigger. If it's 1, don't post as it has already been // triggered and sem_timedwait on this sem *should* not block. sem_getvalue(trigger, &val); if (val <= 0) { printf("sem%d send sync sem%d. val before %d\n", num, (num == 3 ? 1 : num+1), val); sem_post(trigger); } else printf("!! sem%d not sending sync, val %d\n", num, val); } } int main(int argc, char *argv[]) { pthread_t t1, t2, t3; // create semaphores. val of sem1 is 1 to trigger straight away and start the whole ball rolling. if (sem_init(&trigger_sem1, 0, 1) == -1) perror("Error creating trigger_listman semaphore"); if (sem_init(&trigger_sem2, 0, 0) == -1) perror("Error creating trigger_comms semaphore"); if (sem_init(&trigger_sem3, 0, 0) == -1) perror("Error creating trigger_vws semaphore"); pthread_create(&t1, NULL, thread, (void *) 1); pthread_create(&t2, NULL, thread, (void *) 2); pthread_create(&t3, NULL, thread, (void *) 3); pthread_join(t1, NULL); pthread_join(t2, NULL); pthread_join(t3, NULL); } The following output is printed when the program is running correctly (at the start and for a random but long time after). The value of sem1 is always 1 before thread1 waits as it sleeps for 40ms, by which time sem3 has triggered it, so it wakes straight away. The other two threads wait until the semaphore is received from the previous thread. [...] sem1 wait sync sem1. val before 1 sem1 wakeup. sem1 send sync sem2. val before 0 sem2 wakeup. sem2 send sync sem3. val before 0 sem2 wait sync sem2. val before 0 sem3 wakeup. sem3 send sync sem1. val before 0 sem3 wait sync sem3. val before 0 sem1 wait sync sem1. val before 1 sem1 wakeup. sem1 send sync sem2. val before 0 [...] However, after a few hours, one of the threads begins to timeout. I can see from the output that the semaphore is being triggered, and when I print the value after the timeout is is 1. So sem_timedwait should have woken up well before the timeout. I would never expect the value of the semaphore to be 1 after the timeout, save for the very rare occasion (almost certainly never but it's possible) when the trigger happens after the timeout but before I call sem_getvalue. Also, once it begins to fail, every sem_timedwait() on that semaphore also fails in the same way. See the following output, which I've line-numbered: 01 sem3 wait sync sem3. val before 0 02 sem1 wakeup. 03 sem1 send sync sem2. val before 0 04 sem2 wakeup. 05 sem2 send sync sem3. val before 0 06 sem2 wait sync sem2. val before 0 07 sem1 wait sync sem1. val before 0 08 !!!!!! sem3 sem_timedwait failed: Connection timed out, val now 1 09 sem3 send sync sem1. val before 0 10 sem3 wait sync sem3. val before 1 11 sem3 wakeup. 12 !! sem3 not sending sync, val 1 13 sem3 wait sync sem3. val before 0 14 sem1 wakeup. [...] On line 1, thread 3 (which I have confusingly called sem1 in the printf) waits for sem3 to be triggered. On line 5, sem2 calls sem_post for sem3. However, line 8 shows sem3 timing out, but the value of the semaphore is 1. thread3 then triggers sem1 and waits again (10). However, because the value is already 1, it wakes straight away. It doesn't send sem1 again as this has all happened before control is given to thread1, however it then waits again (val is now 0) and sem1 wakes up. This now repeats for ever, sem3 always timing out and showing that the value is 1. So, my question is why does sem3 timeout, even though the semaphore has been triggered and the value is clearly 1? I would never expect to see line 08 in the output. If it times out (because, say thread 2 has crashed or is taking too long), the value should be 0. And why does it work fine for 3 or 4 hours first before getting into this state? This is using Ubuntu 9.4 with kernel 2.6.28. The same procedure has been working properly on Redhat and Fedora. But I'm now trying to port to ubuntu! Thanks for any advice, Giles

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