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  • Help with iphone dev - beyond bounds error

    - by dusk
    I'm just learning iphone development, so please forgive me for what is probably a beginner error. I've searched around and haven't found anything specific to my problem, so hopefully it is an easy fix. The book has examples of building a table from data hard coded via an array. Unfortunately it never really tells you how to get data from a URL, so I've had to look that up and that is where my problems show up. When I debug in xcode, it seems like the count is correct, so I don't understand why it is going out of bounds? This is the error message: 2010-05-03 12:50:42.705 Simple Table[3310:20b] *** Terminating app due to uncaught exception 'NSRangeException', reason: '*** -[NSCFArray objectAtIndex:]: index (1) beyond bounds (0)' My URL returns the following string: first,second,third,fourth And here is the iphone code with the book's working example commented out #import "Simple_TableViewController.h" @implementation Simple_TableViewController @synthesize listData; - (void)viewDidLoad { /* //working code from book NSArray *array = [[NSArray alloc] initWithObjects:@"Sleepy", @"Sneezy", @"Bashful", @"Bashful", @"Happy", @"Doc", @"Grumpy", @"Thorin", @"Dorin", @"Norin", @"Ori", @"Balin", @"Dwalin", @"Fili", @"Kili", @"Oin", @"Gloin", @"Bifur", @"Bofur", @"Bombur", nil]; self.listData = array; [array release]; */ //code from interwebz that crashes NSString *urlstr = [[NSString alloc] initWithFormat:@"http://www.mysite.com/folder/iphone-test.php"]; NSURL *url = [[NSURL alloc] initWithString:urlstr]; NSString *ans = [NSString stringWithContentsOfURL:url]; NSArray *listItems = [ans componentsSeparatedByString:@","]; self.listData = listItems; [urlstr release]; [url release]; [ans release]; [listItems release]; [super viewDidLoad]; } - (void)didReceiveMemoryWarning { // Releases the view if it doesn't have a superview. [super didReceiveMemoryWarning]; // Release any cached data, images, etc that aren't in use. } - (void)viewDidUnload { // Release any retained subviews of the main view. // e.g. self.myOutlet = nil; self.listData = nil; [super viewDidUnload]; } - (void)dealloc { [listData release]; [super dealloc]; } #pragma mark - #pragma mark Table View Data Source Methods - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { return [self.listData count]; } - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *SimpleTableIdentifier = @"SimpleTableIdentifier"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:SimpleTableIdentifier]; if (cell == nil) { cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:SimpleTableIdentifier] autorelease]; } NSUInteger row = [indexPath row]; cell.textLabel.text = [listData objectAtIndex:row]; return cell; } @end

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  • cannot retrieve effect.fx file

    - by numerical25
    I am having issues loading my effect.fx from directx. When I step into my application, my ID3D10Effect *m_pDefaultEffect; pointer remains empty. the address remains at 0x000000 below is my code #pragma once #include "stdafx.h" #include "resource.h" #include "d3d10.h" #include "d3dx10.h" #include "dinput.h" #define MAX_LOADSTRING 100 class RenderEngine { protected: RECT m_screenRect; //direct3d Members ID3D10Device *m_pDevice; // The IDirect3DDevice10 // interface ID3D10Texture2D *m_pBackBuffer; // Pointer to the back buffer ID3D10RenderTargetView *m_pRenderTargetView; // Pointer to render target view IDXGISwapChain *m_pSwapChain; // Pointer to the swap chain RECT m_rcScreenRect; // The dimensions of the screen ID3D10Texture2D *m_pDepthStencilBuffer; ID3D10DepthStencilState *m_pDepthStencilState; ID3D10DepthStencilView *m_pDepthStencilView; //transformation matrixs D3DXMATRIX g_mtxWorld; D3DXMATRIX g_mtxView; D3DXMATRIX g_mtxProj; //Effect members ID3D10Effect *m_pDefaultEffect; ID3D10EffectTechnique *m_pDefaultTechnique; ID3DX10Font *m_pFont; // The font used for rendering text // Sprites used to hold font characters ID3DX10Sprite *m_pFontSprite; ATOM RegisterEngineClass(); void DoFrame(float); bool LoadEffects(); public: static HINSTANCE m_hInst; HWND m_hWnd; int m_nCmdShow; TCHAR m_szTitle[MAX_LOADSTRING]; // The title bar text TCHAR m_szWindowClass[MAX_LOADSTRING]; // the main window class name void DrawTextString(int x, int y, D3DXCOLOR color, const TCHAR *strOutput); //static functions static LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam); static INT_PTR CALLBACK About(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam); bool InitWindow(); bool InitDirectX(); bool InitInstance(); int Run(); void ShutDown(); RenderEngine() { m_screenRect.right = 800; m_screenRect.bottom = 600; } }; below is the implementation bool RenderEngine::LoadEffects() { HRESULT hr; ID3D10Blob *pErrors = 0; // Create the default rendering effect hr = D3DX10CreateEffectFromFile(L"effect.fx", NULL, NULL, "fx_4_0", D3D10_SHADER_DEBUG, 0, m_pDevice, NULL, NULL, &m_pDefaultEffect, &pErrors, NULL); if(pErrors)// at this point, m_pDefaultEffect is still empty but pErrors returns data which means there is {//errors return false; //ends here } //m_pDefaultTechnique = m_pDefaultEffect->GetTechniqueByName("DefaultTechnique"); return true; } My directx Device does work. My effect.fx file is in the same folder as my solution files (.cpp and header files)

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  • GCC: Simple inheritance test fails

    - by knight666
    I'm building an open source 2D game engine called YoghurtGum. Right now I'm working on the Android port, using the NDK provided by Google. I was going mad because of the errors I was getting in my application, so I made a simple test program: class Base { public: Base() { } virtual ~Base() { } }; // class Base class Vehicle : virtual public Base { public: Vehicle() : Base() { } ~Vehicle() { } }; // class Vehicle class Car : public Vehicle { public: Car() : Base(), Vehicle() { } ~Car() { } }; // class Car int main(int a_Data, char** argv) { Car* stupid = new Car(); return 0; } Seems easy enough, right? Here's how I compile it, which is the same way I compile the rest of my code: /home/oem/android-ndk-r3/build/prebuilt/linux-x86/arm-eabi-4.4.0/bin/arm-eabi-g++ -g -std=c99 -Wall -Werror -O2 -w -shared -fshort-enums -I ../../YoghurtGum/src/GLES -I ../../YoghurtGum/src -I /home/oem/android-ndk-r3/build/platforms/android-5/arch-arm/usr/include -c src/Inheritance.cpp -o intermediate/Inheritance.o (Line breaks are added for clarity). This compiles fine. But then we get to the linker: /home/oem/android-ndk-r3/build/prebuilt/linux-x86/arm-eabi-4.4.0/bin/arm-eabi-gcc -lstdc++ -Wl, --entry=main, -rpath-link=/system/lib, -rpath-link=/home/oem/android-ndk-r3/build/platforms/android-5/arch-arm/usr/lib, -dynamic-linker=/system/bin/linker, -L/home/oem/android-ndk-r3/build/prebuilt/linux-x86/arm-eabi-4.4.0/lib/gcc/arm-eabi/4.4.0, -L/home/oem/android-ndk-r3/build/platforms/android-5/arch-arm/usr/lib, -rpath=../../YoghurtGum/lib/GLES -nostdlib -lm -lc -lGLESv1_CM -z /home/oem/android-ndk-r3/build/platforms/android-5/arch-arm/usr/lib/crtbegin_dynamic.o /home/oem/android-ndk-r3/build/platforms/android-5/arch-arm/usr/lib/crtend_android.o intermediate/Inheritance.o ../../YoghurtGum/bin/YoghurtGum.a -o bin/Galaxians.android As you can probably tell, there's a lot of cruft in there that isn't really needed. That's because it doesn't work. It fails with the following errors: intermediate/Inheritance.o:(.rodata._ZTI3Car[typeinfo for Car]+0x0): undefined reference to `vtable for __cxxabiv1::__si_class_type_info' intermediate/Inheritance.o:(.rodata._ZTI7Vehicle[typeinfo for Vehicle]+0x0): undefined reference to `vtable for __cxxabiv1::__vmi_class_type_info' intermediate/Inheritance.o:(.rodata._ZTI4Base[typeinfo for Base]+0x0): undefined reference to `vtable for __cxxabiv1::__class_type_info' collect2: ld returned 1 exit status make: *** [bin/Galaxians.android] Fout 1 These are the same errors I get from my actual application. If someone could explain to me where I went wrong in my test or what option or I forgot in my linker, I would be very, extremely grateful. Thanks in advance. UPDATE: When I make my destructors non-inlined, I get new and more exciting link errors: intermediate/Inheritance.o:(.rodata+0x78): undefined reference to `vtable for __cxxabiv1::__si_class_type_info' intermediate/Inheritance.o:(.rodata+0x90): undefined reference to `vtable for __cxxabiv1::__vmi_class_type_info' intermediate/Inheritance.o:(.rodata+0xb0): undefined reference to `vtable for __cxxabiv1::__class_type_info' collect2: ld returned 1 exit status make: *** [bin/Galaxians.android] Fout 1

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  • Qt - problem appending to QList of QList

    - by bullettime
    I'm trying to append items to a QList at runtime, but I'm running on a error message. Basically what I'm trying to do is to make a QList of QLists and add a few customClass objects to each of the inner lists. Here's my code: widget.h: class Widget : public QWidget { Q_OBJECT public: Widget(QWidget *parent = 0); ~Widget(); public slots: static QList<QList<customClass> > testlist(){ QList<QList<customClass> > mylist; for(int w=0 ; w<5 ; w++){ mylist.append(QList<customClass>()); } for(int z=0 ; z<mylist.size() ; z++){ for(int x=0 ; x<10 ; x++){ customClass co = customClass(); mylist.at(z).append(co); } } return mylist; } }; customclass.h: class customClass { public: customClass(){ this->varInt = 1; this->varQString = "hello world"; } int varInt; QString varQString; }; main.cpp: int main(int argc, char *argv[]) { QApplication a(argc, argv); Widget w; QList<QList<customClass> > list; list = w.testlist(); w.show(); return a.exec(); } But when I try to run the application, it gives off this error: error: passing `const QList<customClass>' as `this' argument of `void List<T>::append(const T&) [with T = customClass]' discards qualifiers I also tried inserting the objects using foreach: foreach(QList<customClass> list, mylist){ for(int x=0 ; x<10 ; x++){ list.append(customClass()); } } The error was gone, but the customClass objects weren't appended, I could verify that by using a debugging loop in main that showed the inner QLists sizes as zero. What am I doing wrong?

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  • Animation using AniMate with Unity3D doesn't interact with physical objects

    - by Albz
    I'm designing a maze with Unity3D. The maze has a number of bifurcations and the player will stop before each bifurcation and simply choose left or right. Then an automatic animation will move the player through the next bifurcation till the end of the maze (or till a dead end). To animate the player I'm using AniMate and C# in my Unity project. Using AniMate I'm simply creating a point-to-point animation for each bifurcation (e.g. mage below: from the start/red arrow to point 5) My problem is that my animation script (associated to the "First Person Controller") is not working properly since physics is not respected (the player passes through walls). If in the same project I enable the standard character controls in Unity, then I can navigate in the maze with the physical contrains of walls etc... (i.e. I have colliders). This is an example of the code I'm using when I press left to pass from starting point, trough point 1 to point 2: void FixedUpdate () { if (Input.GetKey(KeyCode.LeftArrow)) { //To point 1 Hashtable props = new Hashtable(); props.Add("position", new Vector3(756f,112f,1124f)); props.Add("physics", true); Ani.Mate.To(transform, 2, props); //To point 2 Hashtable props2 = new Hashtable(); props2.Add("position", new Vector3(731f,112f,1124f)); props2.Add("physics", true); Ani.Mate.To(transform, 2, props2); } } What happens practically when I press the left arrow button is that the player moves directly to point 2 using a straight line passing through the wall. I tried to pass to AniMate "Physics = true" but it doesn't seem to help. Any idea on how to solve this issue? Alternatively... any hint on how to have a more optimized code and just use a series of vector3 coordinates (one for each point) to obtain the simple animation I want without having to declare new Hashtable(); etc... every time? I chose AniMate simply because 1. I'm a beginner with Unity 2. I don't need complex animations (e.g. I don't need to use iTween), just fixed animations along straight lines and I need something really simple and quick to implement in a script. However, if someone has an equally simple solution it will be welcome. thank you in advance for your help

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  • Any tips on reducing wxWidgets application code size?

    - by Billy ONeal
    I have written a minimal wxWidgets application: stdafx.h #define wxNO_REGEX_LIB #define wxNO_XML_LIB #define wxNO_NET_LIB #define wxNO_EXPAT_LIB #define wxNO_JPEG_LIB #define wxNO_PNG_LIB #define wxNO_TIFF_LIB #define wxNO_ZLIB_LIB #define wxNO_ADV_LIB #define wxNO_HTML_LIB #define wxNO_GL_LIB #define wxNO_QA_LIB #define wxNO_XRC_LIB #define wxNO_AUI_LIB #define wxNO_PROPGRID_LIB #define wxNO_RIBBON_LIB #define wxNO_RICHTEXT_LIB #define wxNO_MEDIA_LIB #define wxNO_STC_LIB #include <wx/wxprec.h> Minimal.cpp #include "stdafx.h" #include <memory> #include <wx/wx.h> class Minimal : public wxApp { public: virtual bool OnInit(); }; IMPLEMENT_APP(Minimal) DECLARE_APP(Minimal) class MinimalFrame : public wxFrame { DECLARE_EVENT_TABLE() public: MinimalFrame(const wxString& title); void OnQuit(wxCommandEvent& e); void OnAbout(wxCommandEvent& e); }; BEGIN_EVENT_TABLE(MinimalFrame, wxFrame) EVT_MENU(wxID_ABOUT, MinimalFrame::OnAbout) EVT_MENU(wxID_EXIT, MinimalFrame::OnQuit) END_EVENT_TABLE() MinimalFrame::MinimalFrame(const wxString& title) : wxFrame(0, wxID_ANY, title) { std::auto_ptr<wxMenu> fileMenu(new wxMenu); fileMenu->Append(wxID_EXIT, L"E&xit\tAlt-X", L"Terminate the Minimal Example."); std::auto_ptr<wxMenu> helpMenu(new wxMenu); helpMenu->Append(wxID_ABOUT, L"&About\tF1", L"Show the about dialog box."); std::auto_ptr<wxMenuBar> bar(new wxMenuBar); bar->Append(fileMenu.get(), L"&File"); fileMenu.release(); bar->Append(helpMenu.get(), L"&Help"); helpMenu.release(); SetMenuBar(bar.get()); bar.release(); CreateStatusBar(2); SetStatusText(L"Welcome to wxWidgets!"); } void MinimalFrame::OnAbout(wxCommandEvent& e) { wxMessageBox(L"Some text about me!", L"About", wxOK, this); } void MinimalFrame::OnQuit(wxCommandEvent& e) { Close(); } bool Minimal::OnInit() { std::auto_ptr<MinimalFrame> mainFrame( new MinimalFrame(L"Minimal wxWidgets Application")); mainFrame->Show(); mainFrame.release(); return true; } This minimal program weighs in at 2.4MB! (Executable compression drops this to half a MB or so but that's still HUGE!) (I must statically link because this application needs to be single-binary-xcopy-deployed, so both the C runtime and wxWidgets itself are set for static linking) Any tips on cutting this down? (I'm using Microsoft Visual Studio 2010)

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  • Reading a file with a supplied name in C++

    - by Cosmina
    I must read a file with a given name (it's caled "hamlet.txt"). The class used to read the file is defined like this #ifndef READWORDS_H #define READWORDS_H /** * ReadWords class. Provides mechanisms to read a text file, and return * capitalized words from that file. */ using namespace std; #include <string> #include <fstream> class ReadWords { public: /** * Constructor. Opens the file with the default name "text.txt". * Program exits with an error message if the file does not exist. */ ReadWords(); /** * Constructor. Opens the file with the given filename. * Program exits with an error message if the file does not exist. * @param filename - a C string naming the file to read. */ ReadWords(char *filename); My definition of the members of the classis this: #include<string> #include<fstream> #include<iostream> #include "ReadWords.h" using namespace std; ReadWords::ReadWords() { wordfile.open("text.txt"); if( !wordfile ) { cout<<"Errors while opening the file!"<<endl; } } ReadWords::ReadWords(char *filename) { wordfile.open(filename); if ( !wordfile ) { cout<<"Errors while opening the file!"<<endl; } wordfile>>nextword; } And the main to test it. using namespace std; #include #include #include "ReadWords.h" int main() { char name[30]; cout<<"Please input a name for the file that you wish to open"; cin>>name; ReadWords x( name[] ); } When I complie it gives me the error: main.cpp:14: error: expected primary-expression before ']' token I know it's got something to do with the function ReadWords( char *filename), but I do not know what. Any help please?

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  • Load on page inside another onClick

    - by Robin I Knight
    Hello, I need to include the content, scripts, forms and dynamic abilities of one page in another onClick. Take a look at http://www.divethegap.com/scuba-diving-programmes-dive-the-gap/dahab-master-scuba-diver.html Then follow one of the links that says 'Beginner' 'Open Water Diver' etc.... You will find a PHP page with a series of options. It is an adaption of the wordpress blog system to produce only specific options for specific programmes by considering each type of each diving programme a category and then displaying only results from that category. You will see that each option is also a collapsible panel and there are also several javascripts that calculate durations, quantities and prices. There is also a validating webform at the end. Now go back to the first page. What I would like to do is include all the content from the second page after the main header inside tabbed panels on the first page so that the customers can immidietly see everything that is included. Essentially the options on the first page would become a series of tabs. The only way I can see to do this is with an iFrame as each option would need a unique URL ending (that is .php?cat=26 or .php?cat=27). THe problem is that the collapsible panels will not work with an iFrame as the iFrame will not resize when the panels open. There were also some calculation problems, but I think that was more down to me staring at the screen for the last 3 hours not remembering to include everything. I have tried it with resizing iframe SSI scripts and have got nowhere. I tried actually embedding it in the page better with a ajax script, but that left behind all the scripts that make it work. I checked with full URL's on everything and it would not take work with any scripts. I know that you could just make the whole page reload but then the user would be at the top of the page again, and even if another script was applied to slowly bring them down again it would not be anything near as easy to use as if it was like tabbed panels. Any ideas. Kind Regards,

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  • Strange behaviour of NSString in NSView

    - by Mee
    Trying to create a Skat-Game, I encountered the following problem: isBidding is a Boolean value indicationg, the program is in a certain state, [desk selected] is a method calling returning the current selected player, chatStrings consists of dictionaries, saving strings with the player, who typed, and what he typed - (void)drawRect:(NSRect)rect { NSMutableDictionary * attributes = [NSMutableDictionary dictionary]; [attributes setObject:[NSFont fontWithName:playerFont size:playerFontSize] forKey:NSFontAttributeName]; [attributes setObject:playerFontColor forKey:NSForegroundColorAttributeName]; [[NSString stringWithFormat:@"Player %i",[desk selected] + 1]drawInRect:playerStringRect withAttributes:attributes]; if (isBidding) { [attributes setObject:[NSFont fontWithName:chatFont size:chatFontSize] forKey:NSFontAttributeName]; [attributes setObject:chatFontColor forKey:NSForegroundColorAttributeName]; int i; for (i = 0; i < [chatStrings count]; i++, yProgress -= 20) { if (isBidding) [[NSString stringWithFormat:@"Player %i bids: %@",[[[chatStrings objectAtIndex:i]valueForKey:@"Player"]intValue], [[chatStrings objectAtIndex:i]valueForKey:@"String"]] drawAtPoint:NSMakePoint([self bounds].origin.x, yProgress) withAttributes:attributes]; else [[NSString stringWithFormat:@"Player %i: %@",[[[chatStrings objectAtIndex:i]valueForKey:@"Player"]intValue], [[chatStrings objectAtIndex:i]valueForKey:@"String"]] drawAtPoint:NSMakePoint([self bounds].origin.x, yProgress) withAttributes:attributes]; } if (isBidding) [[NSString stringWithFormat:@"Player %i bids: %@",[desk selected] + 1, displayString] drawAtPoint:NSMakePoint([self bounds].origin.x, yProgress) withAttributes:attributes]; else [[NSString stringWithFormat:@"Player %i: %@",[desk selected] + 1, displayString] drawAtPoint:NSMakePoint([self bounds].origin.x, yProgress) withAttributes:attributes]; yProgress = chatFontBegin; } } This is the part determining the string's content, the string is contributed by an [event characters] method. -(void)displayChatString:(NSString *)string { displayString = [displayString stringByAppendingString:string]; [self setNeedsDisplay:YES]; } The problem if have is this: when typing in more than two letters the view displays NSRectSet{{{471, 574},{500, 192}}} and returns no more discription when I try to print it. then I get an EXC_BAD_ACCESS message, though I have not released it (as far as I can see) I also created the string with alloc and init, so I cannot be in the autorelease pool. I also tried to watch the process when it changes with the debugger, but I couldn't find any responsible code. As you can see I am still a beginner in Cocoa (and programming in general), so I would be really happy if somebody would help me with this.

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  • How to measure a canvas that has auto height and with

    - by Wymmeroo
    Hi Folks, I'm a beginner in silverlight so i hope i can get an answer that brings me some more light in the measure process of silverlight. I found an interessting flap out control from silverlight slide control and now I try to use it in my project. So that the slide out is working proper, I have to place the user control on a canvas. The user control then uses for itself the height of its content. I just wanna change that behavior so that the height is set to the available space from the parent canvas. You see the uxBorder where the height is set. How can I measure the actual height and set it to the border? I tried it with Height={Binding ElementName=notificationCanvas, Path=ActualHeight} but this dependency property has no callback, so the actualHeight is never set. What I want to achieve is a usercontrol like the tweetboard per example on Jesse Liberty's blog Sorry for my English writing, I hope you understand my question. <Canvas x:Name="notificationCanvas" Background="Red"> <SlideEffectEx:SimpleSlideControl GripWidth="20" GripTitle="Task" GripHeight="100"> <Border x:Name="uxBorder" BorderThickness="2" CornerRadius="5" BorderBrush="DarkGray" Background="DarkGray" Padding="5" Width="300" Height="700" > <StackPanel> <TextBlock Text="Tasks"></TextBlock> <Button x:Name="btn1" Margin="5" Content="{Binding ElementName=MainBorder, Path=Height}"></Button> <Button x:Name="btn2" Margin="5" Content="Second Button"></Button> <Button x:Name="btn3" Margin="5" Content="Third Button"></Button> <Button x:Name="btn1_Copy" Margin="5" Content="First Button"/> <Button x:Name="btn1_Copy1" Margin="5" Content="First Button"/> <Button x:Name="btn1_Copy2" Margin="5" Content="First Button"/> <Button x:Name="btn1_Copy3" Margin="5" Content="First Button"/> <Button x:Name="btn1_Copy4" Margin="5" Content="First Button"/> <Button x:Name="btn1_Copy5" Margin="5" Content="First Button"/> <Button x:Name="btn1_Copy6" Margin="5" Content="First Button"/> </StackPanel> </Border> </SlideEffectEx:SimpleSlideControl>

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  • Shortening jQuery Code by Replacing Variable

    - by Jerry
    I have a form with a bunch of dropdown options that I'm dressing up by allowing the option to be selected by clicking links and (in the future, images) instead of using the actual dropdown. There are a lot of dropdowns and most all will repeat the same basic idea, and some will literally repeat just with different variables. Here's the HTML for one of those. <tr class="box1"> <td> <select id="cimy_uef_7"> <option value="Boy">Boy</option> <option value="Girl">Girl</option> </select> </td> </tr> Then the corresponding fancier links to click that will select the corresponding option in the dropdown. <div id="genderBox1"> <div class="gender"><a class="boy" href="">Boy</a></div> <div class="gender"><a class="girl" href="">Girl</a></div> </div> So, when you click the link "Boy" it will select the corresponding dropdown value "Boy" There are going to be multiple Box#, so I can just repeat the jQuery each time with the new variables, but there's surely a shorter way. Here's the jQuery that makes it work. //Box1 Gender var Gender1 = $('select#cimy_uef_7'); var Boy1 = $("#genderBox1 .gender a.boy"); var Girl1 = $("#genderBox1 .gender a.girl"); //On Page Load - Check Gender Box 1 Selection and addClass to corresponding div a if ( $(Gender1).val() == "Boy" ) { $(Boy1).addClass("selected"); } else { $(Boy1).removeClass("selected"); } if ( $(Gender1).val() == "Girl" ) { $(Girl1).addClass("selected"); } else { $(Girl1).removeClass("selected"); } //On Click - Change Gender Box 1 select based on image click $(Boy1).click(function(event) { event.preventDefault(); $(this).addClass("selected"); $(Gender1).val("Boy"); $(Girl1).removeClass("selected"); }); $(Girl1).click(function(event) { event.preventDefault(); $(this).addClass("selected"); $(Gender1).val("Girl"); $(Boy1).removeClass("selected"); }); My thought for shortening it was to just have a list of variables for each box and cycle through the numbers- 1,2,3,4 and have the jQuery grab the same # for each variable, but I can't figure out a way to do it. Let me know if there's anything else I can provide to make the question better. This is my best idea for shortening this code, as I'm still very much a beginner at jQuery, but I'm positive there are much better ideas out there, so feel free to recommend a better path if you see it :)

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  • Variable lenght arguments in log4cxx LOG4CXX_ macros

    - by Horacio
    I am using log4cxx in a big C++ project but I really don't like how log4cxx handles multiple variables when logging: LOG4CXX_DEBUG(logger, "test " << var1 << " and " << var3 " and .....) I prefer using printf like variable length arguments: LOG4CXX_DEBUG(logger, "test %d and %d", var1, var3) So I implemented this small wrapper on top of log4cxx #include <string.h> #include <stdio.h> #include <stdarg.h> #include <log4cxx/logger.h> #include "log4cxx/basicconfigurator.h" const char * log_format(const char *fmt, ...); #define MYLOG_TRACE(logger, fmt, ...) LOG4CXX_TRACE(logger, log_format(fmt, ## __VA_ARGS__)) #define MYLOG_DEBUG(logger, fmt, ...) LOG4CXX_DEBUG(logger, log_format(fmt, ## __VA_ARGS__)) #define MYLOG_INFO(logger, fmt, ...) LOG4CXX_INFO(logger, log_format(fmt, ## __VA_ARGS__)) #define MYLOG_WARN(logger, fmt, ...) LOG4CXX_WARN(logger, log_format(fmt, ## __VA_ARGS__)) #define MYLOG_ERROR(logger, fmt, ...) LOG4CXX_ERROR(logger, log_format(fmt, ## __VA_ARGS__)) #define MYLOG_FATAL(logger, fmt, ...) LOG4CXX_FATAL(logger, log_format(fmt, ## __VA_ARGS__)) static log4cxx::LoggerPtr logger(log4cxx::Logger::getRootLogger()); int main(int argc, char **argv) { log4cxx::BasicConfigurator::configure(); MYLOG_INFO(logger, "Start "); MYLOG_WARN(logger, log_format("In running this in %d threads safe?", 1000)); MYLOG_INFO(logger, "End "); return 0; } const char *log_format(const char *fmt, ...) { va_list va; static char formatted[1024]; va_start(va, fmt); vsprintf(formatted, 1024, fmt, va); va_end(va); return formatted; } And this works perfectly but I know using that static variable (formatted) can become problematic if I start using threads and each thread logging to the same place. I am no expert in log4cxx so I was wondering if the LOG4CXX macros are handling concurrent thread access automatically? or do I have to implement some sort of locking around the log_format method? something that I wan't to avoid due to performance implications. Also I would like to ask why if I replace the vsprintf inside the log_format method with vsnprintf (that is more secure) then I get nothing printed? To compile and test this program (in Ubuntu) use : g++ -o loggertest loggertest.cpp -llog4cxx

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  • C++ snippet support in visual studio?

    - by Jeremy Bell
    I'm writing code in native C++ (not C++/CLR). I know that there is no built-in support for C++ with regards to the snippet manager and snipper picker interfaces, however I found a utility called "snippy" which supposedly can generate C++ snippets. Here is a c++ snippet that the program generated: <?xml version="1.0" encoding="utf-8"?> <CodeSnippets xmlns="http://schemas.microsoft.com/VisualStudio/2005/CodeSnippet"> <CodeSnippet Format="1.0.0"> <Header> <Title>MySnippet</Title> <Shortcut>MySnippet</Shortcut> <Description>Just a test snippet</Description> <Author>Me</Author> <SnippetTypes> <SnippetType>Expansion</SnippetType> </SnippetTypes> </Header> <Snippet> <Declarations> <Literal Editable="true"> <ID>literal1</ID> <ToolTip>just a placeholder</ToolTip> <Default> </Default> <Function> </Function> </Literal> </Declarations> <Code Language="cpp"><![CDATA[cout << "$literal1$" << std::endl;]]></Code> </Snippet> </CodeSnippet> </CodeSnippets> If there is support in visual C++, even in a limited capacity, for C++ snippets, how do I add them to my environment, and what are the limitations? All I need is support for basic expansion snippets that I can invoke by typing a shortcut and hitting tab, and which supports basic literals that I can tab through (basically, if it supports the above snippet, I'm good). If this can't be done, are there any free add-ons or extensions to visual studio that support snippets for C++? I'm using both visual studio 2010 and 2008, but I mostly write code in 2010 right now.

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  • How to enable UAC prompt through programming

    - by peter
    I want to implement a UAC prompt for an application in visualc++ the operating system is 32bit x7460(2processor) Windowsserver 2008 the exe is myproject.exe through manifest.. Here for testing i wl build the application in Windows XP OS and copy the exe in to system containg the Windowsserver 2008 machine and replace it So what i did is i added a manifest like this name of that is myproject.exe.manifest My project has 3 folders like Headerfile,Resourcefile and Source file.I added this manifest(myproject.exe.manifest) in the Sourcefile folder containing other cpp and c code <?xml version="1.0" encoding="UTF-8" standalone="yes"?> <assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0"> <assemblyIdentity version="11.1.4.0" processorArchitecture="X7460" name="myproject" type="win32"/> <description>myproject Problem</description> <!-- Identify the application security requirements. --> <trustInfo xmlns="urn:schemas-microsoft-com:asm.v2"> <security> <requestedPrivileges> <requestedExecutionLevel level="requireAdministrator" uiAccess="false"/> </requestedPrivileges> </security> </trustInfo> </assembly> then i added this line of code in Resourcefile(.rc).Means one header file is there(Myproject.h).I added the line of code there #define MANIFEST_RESOURCE_ID 1 MANIFEST_RESOURCE_ID RT_MANIFEST "myproject.exe.manifest" Finally i did the following step 1. Open your project in Microsoft Visual Studio 2005. 2. Under Project, select Properties. 3. In Properties, select Manifest Tool, and then select Input and Output. 4. Add in the name of your application manifest file under Additional manifest files. 5. Rebuild your application. But i am getting lot of Syntax errors Is there any problems in the way which i followed.If i commented the line define MANIFEST_RESOURCE_ID 1 MANIFEST_RESOURCE_ID RT_MANIFEST "myproject.exe.manifest" which added in Myproject.h for adding values in .rc file there willnot any error other than this general error c1010070: Failed to load and parse the manifest. The system cannot find the file specified. .\myproject.exe.manifest How to enable UAC prompt through programming

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  • What would you suggest as a high school first language?

    - by ldigas
    Edit by OA: After reading some answers I'll just update the question a little. At first I put it a little bluntly, but some of those gave me some good arguments which have to be taken into consideration while making a stand on this one. (these are mostly picked up from comments and answers below). A few things to take into account: to many pupils this is a first programming language - at this stage most of them have trouble grasping a difference between data types, variable passing, ... and whatnot, less alone pointers and similar 'low level stuff' :) they will all have to pass this to get into next grade (well, big majority of them anyway) not all of them have computers at home, not all of them are willing to learn this, less alone interested in - so the concepts have to be taught on a finite time scale in school hours (as well as practice on computers) free literature is a bonus - the teacher will make some scripts and handaways, but still ... I wouldn't like to bear the parents with the burden of buying expensive literature (also, english is not a native language here ... and although they are all learning it, their ability to read it fluently is somewhat questionable) somebody gave an argument - "a language which does not get in the way of ideas" - good one accessibility on different platforms in not expecially important at this point - although most of the suggested ones are available on win as well as linux - not many macs in this part of europe (their prices are sky high for anything but specialised usage) I will check what are the licencing issues on ms express editions about using it massively in high schools for purposes like this - if someone has any info about this, please, do not be shy with it :) A friend of mine, informatics teacher - in EU it comes as something as junior cs teacher, in a local high school asked me what I thought about what should be the first language pupils should be taught? It is a technical school (a little more oriented towards mathematics than the gymnasium, but not computer oriented totally). So I'm asking you - what do you think should be the first language pupils are exposed to in highschool? They have been teaching Pascal so far, but she's not sure that's a good course. She thought about switching to C (which I resented; considering not all pupils have interests in programming, to start with, and should be taught something higher level since they are just gripping the idea of a loop and such ... for a start), I suggested python or ruby (preferably py since it handles all paradigms). What is your opinion on this one? I looked, but didn't find a similar question on SO, so if there is one, please just point me towards it. Edit: The assumption is that none of the pupils have been exposed to any programming in junior school. See also: What is the best way to teach young kids some basic programming concepts? Best ways to teach a beginner to program How and when do you teach a kid to code What is the easiest language to start with? High School Programming

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  • help Implementing Object Oriented ansi-C approach??

    - by No Money
    Hey there, I am an Intermediate programmer in Java and know some of the basics in C++. I recently started to scam over "C language" [please note that i emphasized on C language and want to stick with C as i found it to be a perfect tool, so no need for suggestions focusing on why should i move back to C++ or Java]. Moving on, I code an Object Oriented approach in C but kindda scramble with the pointers part. Please understand that I am just a noob trying to extend my knowledge beyond what i learned in High School. Here is my code..... #include <stdio.h> typedef struct per{ int privateint; char *privateString; struct per (*New) (); void (*deleteperOBJ) (struct t_person *); void (*setperNumber) ((struct*) t_person,int); void (*setperString) ((struct*) t_person,char *); void (*dumpperState) ((struct*) t_person); }t_person; void setperNumber(t_person *const per,int num){ if(per==NULL) return; per->privateint=num; } void setperString(t_person *const per,char *string){ if(per==NULL) return; per->privateString=string; } void dumpperState(t_person *const per){ if(per==NULL) return; printf("value of private int==%d\n", per->privateint); printf("value of private string==%s\n", per->privateString); } void deleteperOBJ(struct t_person *const per){ free((void*)t_person->per); t_person ->per = NULL; } main(){ t_person *const per = (struct*) malloc(sizeof(t_person)); per = t_person -> struct per -> New(); per -> setperNumber (t_person *per, 123); per -> setperString(t_person *per, "No money"); dumpperState(t_person *per); deleteperOBJ(t_person *per); } Just to warn you, this program has several errors and since I am a beginner I couldn't help except to post this thread as a question. I am looking forward for assistance. Thanks in advance.

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  • Multiplying matrices: error: expected primary-expression before 'struct'

    - by justin
    I am trying to write a program that is supposed to multiply matrices using threads. I am supposed to fill the matrices using random numbers in a thread. I am compiling in g++ and using PTHREADS. I have also created a struct to pass the data from my command line input to the thread so it can generate the matrix of random numbers. The sizes of the two matrices are also passed in the command line as well. I keep getting: main.cpp:7: error: expected primary-expression before 'struct' my code @ line 7 =: struct a{ int Arow; int Acol; int low; int high; }; My inpust are : Sizes of two matrices ( 4 arguments) high and low ranges in which o generate the random numbers between. Complete code: [headers] using namespace std; void *matrixACreate(struct *); void *status; int main(int argc, char * argv[]) { int Arow = atoi(argv[1]); // Matrix A int Acol = atoi(argv[2]); // WxX int Brow = atoi(argv[3]); // Matrix B int Bcol = atoi(argv[4]); // XxZ, int low = atoi(argv[5]); // Range low int high = atoi(argv[6]); struct a{ int Arow; // Matrix A int Acol; // WxX int low; // Range low int high; }; pthread_t matrixAthread; //pthread_t matrixBthread; pthread_t runner; int error, retValue; if (Acol != Brow) { cout << " This matrix cannot be multiplied. FAIL" << endl; return 0; } error = pthread_create(&matrixAthread, NULL, matrixACreate, struct *a); //error = pthread_create(&matrixAthread, NULL, matrixBCreate, sendB); retValue = pthread_join(matrixAthread, &status); //retValue = pthread_join(matrixBthread, &status); return 0; } void matrixACreate(struct * a) { struct a *data = (struct a *) malloc(sizeof(struct a)); data->Arow = Arow; data->Acol = Acol; data->low = low; data->high = high; int range = ((high - low) + 1); cout << Arow << endl<< Acol << endl; }// just trying to print to see if I am in the thread

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  • shipping and handling fee calculation

    - by Newb
    Here is the question: Many companies normally charge a shipping and handling fee for purchases. Create a Web page that allows a user to enter a purchase price into a text box - include a JavaScript function that calculates shipping and handling. Add functionality to the script that adds a minimum shipping and handling fee of $1.50 for any purchase that is less than or equal to $25.00. For any orders over $25.00, add 10% to the total purchase price for shipping and handling, but do not include the $1.50 minimum shipping and handling fee. After you determine the total cost of the order (purchase plus shipping and handling), display it in an alert dialog box. I am beginner at JavaScript and struggling to get my code to work. It does display an alert box with the value entered by the user but doesn't add anything. Although, I don't know why the formula doesn't work. Please help. <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Calculating Shipping & Handling</title> <script type="text/javascript"> /* <![CDATA[ */ var price=[]; var shipping=[]; var total=price+shipping; function calculateShipping(){ if (price <= 25){ shipping = (price + 1.5); } else { shipping = (price * 10 / 100); } window.alert("The purchase price with shipping is " + document.calculate.ent.value); } /* ]]> */ </script> </head> <body> <form name ="calculate" action="" > <p>Enter Purchase Price</p> <input type="text" name="ent" > <input type="button" name="button" value="Submit" onClick="calculateShipping()" /> </form> </body> </html>

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  • C++ addition overload ambiguity

    - by Nate
    I am coming up against a vexing conundrum in my code base. I can't quite tell why my code generates this error, but (for example) std::string does not. class String { public: String(const char*str); friend String operator+ ( const String& lval, const char *rval ); friend String operator+ ( const char *lval, const String& rval ); String operator+ ( const String& rval ); }; The implementation of these is easy enough to imagine on your own. My driver program contains the following: String result, lval("left side "), rval("of string"); char lv[] = "right side ", rv[] = "of string"; result = lv + rval; printf(result); result = (lval + rv); printf(result); Which generates the following error in gcc 4.1.2: driver.cpp:25: error: ISO C++ says that these are ambiguous, even though the worst conversion for the first is better than the worst conversion for the second: String.h:22: note: candidate 1: String operator+(const String&, const char*) String.h:24: note: candidate 2: String String::operator+(const String&) So far so good, right? Sadly, my String(const char *str) constructor is so handy to have as an implicit constructor, that using the explicit keyword to solve this would just cause a different pile of problems. Moreover... std::string doesn't have to resort to this, and I can't figure out why. For example, in basic_string.h, they are declared as follows: template<typename _CharT, typename _Traits, typename _Alloc> basic_string<_CharT, _Traits, _Alloc> operator+(const basic_string<_CharT, _Traits, _Alloc>& __lhs, const basic_string<_CharT, _Traits, _Alloc>& __rhs) template<typename _CharT, typename _Traits, typename _Alloc> basic_string<_CharT,_Traits,_Alloc> operator+(const _CharT* __lhs, const basic_string<_CharT,_Traits,_Alloc>& __rhs); and so on. The basic_string constructor is not declared explicit. How does this not cause the same error I'm getting, and how can I achieve the same behavior??

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  • A NSMutableArray is destroying my life!

    - by camilo
    EDITED to show the relevant part of the code Hi. There's a strange problem with an NSMutableArray which I'm just not understanding... Explaining: I have a NSMutableArray, defined as a property (nonatomic, retain), synthesized, and initialized with 29 elements. realSectionNames = [[NSMutableArray alloc] initWithCapacity:29]; After the initialization, I can insert elements as I wish and everything seems to be working fine. While I'm running the application, however, if I insert a new element in the array, I can print the array in the function where I inserted the element, and everything seems ok. However, when I select a row in the table, and I need to read that array, my application crashes. In fact, it cannot even print the array anymore. Is there any "magical and logical trick" everybody should know when using a NSMutableArray that a beginner like myself can be missing? Thanks a lot. I declare my array as realSectionNames = [[NSMutableArray alloc] initWithCapacity:29]; I insert objects in my array with [realSectionNames addObject:[category categoryFirstLetter]]; although I know i can also insert it with [realSectionNames insertObject:[category categoryFirstLetter] atIndex:i]; where the "i" is the first non-occupied position. After the insertion, I reload the data of my tableView. Printing the array before or after reloading the data shows it has the desired information. After that, selecting a row at the table makes the application crash. This realSectionNames is used in several UITableViewDelegate functions, but for the case it doesn't matter. What truly matters is that printing the array in the beginning of the didSelectRowAtIndexPath function crashes everything (and of course, doesn't print anything). I'm pretty sure it's in that line, for printing anything he line before works (example): NSLog(@"Anything"); NSLog(@"%@", realSectionNames); gives the output: 2010-03-24 15:16:04.146 myApplicationExperience[3527:207] Anything [Session started at 2010-03-24 15:16:04 +0000.] GNU gdb 6.3.50-20050815 (Apple version gdb-967) (Tue Jul 14 02:11:58 UTC 2009) Copyright 2004 Free Software Foundation, Inc. GDB is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Type "show copying" to see the conditions. There is absolutely no warranty for GDB. Type "show warranty" for details. This GDB was configured as "i386-apple-darwin".sharedlibrary apply-load-rules all Attaching to process 3527. Still not understanding what kind of stupidity I've done this time... maybe it's not too late to follow the career of brain surgeon?

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  • How to measure a canvas that has auto height and width

    - by Wymmeroo
    Hi Folks, I'm a beginner in silverlight so i hope i can get an answer that brings me some more light in the measure process of silverlight. I found an interessting flap out control from silverlight slide control and now I try to use it in my project. So that the slide out is working proper, I have to place the user control on a canvas. The user control then uses for itself the height of its content. I just wanna change that behavior so that the height is set to the available space from the parent canvas. You see the uxBorder where the height is set. How can I measure the actual height and set it to the border? I tried it with Height={Binding ElementName=notificationCanvas, Path=ActualHeight} but this dependency property has no callback, so the actualHeight is never set. What I want to achieve is a usercontrol like the tweetboard per example on Jesse Liberty's blog Sorry for my English writing, I hope you understand my question. <Canvas x:Name="notificationCanvas" Background="Red"> <SlideEffectEx:SimpleSlideControl GripWidth="20" GripTitle="Task" GripHeight="100"> <Border x:Name="uxBorder" BorderThickness="2" CornerRadius="5" BorderBrush="DarkGray" Background="DarkGray" Padding="5" Width="300" Height="700" > <StackPanel> <TextBlock Text="Tasks"></TextBlock> <Button x:Name="btn1" Margin="5" Content="{Binding ElementName=MainBorder, Path=Height}"></Button> <Button x:Name="btn2" Margin="5" Content="Second Button"></Button> <Button x:Name="btn3" Margin="5" Content="Third Button"></Button> <Button x:Name="btn1_Copy" Margin="5" Content="First Button"/> <Button x:Name="btn1_Copy1" Margin="5" Content="First Button"/> <Button x:Name="btn1_Copy2" Margin="5" Content="First Button"/> <Button x:Name="btn1_Copy3" Margin="5" Content="First Button"/> <Button x:Name="btn1_Copy4" Margin="5" Content="First Button"/> <Button x:Name="btn1_Copy5" Margin="5" Content="First Button"/> <Button x:Name="btn1_Copy6" Margin="5" Content="First Button"/> </StackPanel> </Border> </SlideEffectEx:SimpleSlideControl>

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  • which way is correct to retrive data from oracle??

    - by rima
    before answer me plz thinking about the futures of these kind of program and answer me plz. I wanna get some data from oracle server like: 1-get all the function,package,procedure and etc for showing them or drop them & etc... 2-compile my *.sql files,get the result if they have problem & etc... becuz I was beginner in oracle first of all I for solve the second problem I try to connect to sqlPlus by RUN sqlplus and trace the output(I mean,I change the output stream of shell and trace what happend and handle the assigned message to customer. NOW THIS PART SUCCEED. just a little bit I have problem with get all result because the output is asynchronous.any way... [in this case I log in to oracle Server by send argument to the sqlplus by make a process in c#] after that I try to get all function,package or procedure name,but I have problem in speed!so I try to use oracle.DataAccess.dll to connect the database. now I m so confusing about: which way is correct way to build a program that work like Oracle Developer! I do not have any experience for like these program how work. If Your answer is I must use the second way follow this part plz: I search a little bit the Golden,PLedit (Benthic software),I have little bit problem how I must create the connection string?because I thinking about how I can find the host name or port number that oracle work on them?? am I need read the TNSNames.Ora file? IF your answer is I must use the first way follow this part plz: do u have any Idea for how I parse the output?because for example the result of a table is so confusing...[i can handle & program it but I really need someone experience,because the important things to me learn how such software work so nice and with quick response?] All of the has different style in output... If you are not sure Can u help me which book can help me in this way i become expert? becuz for example all the C# write just about how u can connect to DB and the DB books write how u can use this DB program,I looking for a book that give me some Idea how develop an interface for do transaction between these two.not simple send and receive data,for example how write a compiler for them. the language of book is not different for me i know C#,java,VB,sql,Oracle Thanks.

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  • Pop-Up Window at inital start up, of android application

    - by Josh Fairbank
    I am trying to find a code that will do a popup at the initial start up on an installed app. Much like a changelog that is starting to appear in more and more apps. I have found some similar codes, but being a beginner I haven't been able to figure out where to exactly put the code in and I always have tons of errors that still do not work once I try and fix them. I am working in Eclipse with an android project, and I'm using a webview to show a website. XML: <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent"> <WebView xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/webview" android:layout_height="fill_parent" android:layout_width="fill_parent" android:scrollbarAlwaysDrawVerticalTrack="false"/> </LinearLayout> Java File: package com.A2Ddesigners.WhatThe; import android.app.Activity; import android.os.Bundle; import android.webkit.WebView; import android.webkit.WebViewClient; import android.view.KeyEvent; public class Whatthe extends Activity { WebView webview; /** Called when the activity is first created. */ @Override public boolean onKeyDown(int keyCode, KeyEvent event) { if ((keyCode == KeyEvent.KEYCODE_BACK) && webview.canGoBack()) { webview.goBack(); return true; } return super.onKeyDown(keyCode, event); } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); webview = (WebView) findViewById(R.id.webview); webview.setWebViewClient(new HelloWebViewClient()); webview.getSettings().setJavaScriptEnabled(true); webview.setInitialScale(50); webview.getSettings().setUseWideViewPort(true); webview.loadUrl("http://mdsitest2.com/"); } private class HelloWebViewClient extends WebViewClient { @Override public boolean shouldOverrideUrlLoading(WebView view, String url) { view.loadUrl(url); return true; } } }

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  • Specializating a template function that takes a universal reference parameter

    - by David Stone
    How do I specialize a template function that takes a universal reference parameter? foo.hpp: template<typename T> void foo(T && t) // universal reference parameter foo.cpp template<> void foo<Class>(Class && class) { // do something complicated } Here, Class is no longer a deduced type and thus is Class exactly; it cannot possibly be Class &, so reference collapsing rules will not help me here. I could perhaps create another specialization that takes a Class & parameter (I'm not sure), but that implies duplicating all of the code contained within foo for every possible combination of rvalue / lvalue references for all parameters, which is what universal references are supposed to avoid. Is there some way to accomplish this? To be more specific about my problem in case there is a better way to solve it: I have a program that can connect to multiple game servers, and each server, for the most part, calls everything by the same name. However, they have slightly different versions for a few things. There are a few different categories that these things can be: a move, an item, etc. I have written a generic sort of "move string to move enum" set of functions for internal code to call, and my server interface code has similar functions. However, some servers have their own internal ID that they communicate with, some use strings, and some use both in different situations. Now what I want to do is make this a little more generic. I want to be able to call something like ServerNamespace::server_cast<Destination>(source). This would allow me to cast from a Move to a std::string or ServerMoveID. Internally, I may need to make a copy (or move from) because some servers require that I keep a history of messages sent. Universal references seem to be the obvious solution to this problem. The header file I'm thinking of right now would expose simply this: namespace ServerNamespace { template<typename Destination, typename Source> Destination server_cast(Source && source); } And the implementation file would define all legal conversions as template specializations.

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  • Objective-C++ Memory Problem

    - by Stephen Furlani
    Hello, I'm having memory woes. I've got a C++ Library (Equalizer from Eyescale) and they use the Traversal Visitor Pattern to allow you to add new functionality to their classes. I've finally figured out how it works, and I've got a Visitor that just returns the properties from one of the objects. (since I don't know how they're allocated). so. My little code does this: VisitorResult AGLContextVisitor::visit( Channel* channel ) { // Search through Nodes, Pipes until we get to the right window. // Add some code to make sure we find the right one? // Not executing the following code as C++ in gdb? eq::Window* w = channel->getWindow(); OSWindow* osw = w->getOSWindow(); AGLWindow* aw = (AGLWindow *)osw; AGLContext agl_ctx = aw->getAGLContext(); this->setContext(agl_ctx); return TRAVERSE_PRUNE; } So here's the problem. eq::Window* w = channel->getWindow(); (gdb) print w 0x0 BUT If I do this: (gdb) set objc-non-blocking-mode off (gdb) print w=channel->getWindow() 0x300effb9 // an honest memory location, and sets w as verified in the Debugger window of XCode. It does the same thing for osw. I don't get it. Why would something work in (gdb) but not in the code? The file is completely a cpp file, but it seems to be running in objc++, since I need to turn blocking off. Help!? I feel like I'm missing some memory-management basic thing here, either with C++ or Obj-C. [edit] channel-getWindow() is supposed to do this: /** @return the parent window. @version 1.0 */ Window* getWindow() { return _window; } The code also executes fine if I run it from a C++-only application. [edit] No... I tried creating a simple stand-alone program since I was tired of running it as a plugin. Messy to debug. And no, it doesn't run in the C++ program either. So I'm really at a loss as to what I'm doing wrong. Thanks, -- Stephen Furlani

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