I am drawing some polygons using the Qt4 GraphicsView framework, and I allow the user to zoom in and out of the drawing. I would like the polygons to get larger and smaller as the user changes zoom levels (scale) in the view, but is there a way to make the outline thickness always remain the same? Thanks! ...
Hi All, I am going to develop voip,iptv based application using QT on OS-WinXP and Platform-Atom processor for handheld device As a application programmer point of view if I will not think about the drivers what are the other things I need to consider for this project? Like what should be the software layers in the handheld device? I ...
A call to clear on a QByteArray generates the following exception: * glibc detected * /home/yan/FPS2/FPS2: double free or corruption (fasttop): 0 ?? 1 ?? 2 free 3 QByteArray::clear() 4 FPSengine::getDatagrams 5 FPSengine::xmitData 6 FPSengine::getData 7 threadDatalog::run 8 ?? 9 start_thread 10 clone 11 ?? 0 is this a qt ...
Hi, I created a dll with custom Qt widgets implemented, this dll can be recognized by Qt designer and all the widgets works well in the designer. But when I add some additional references for this dll, it cannot be recognized anymore. I tried to add the referenced dlls into designer folder, but still failed. Could anyone give me any s...
I come from a fairly strong C background, and have a rather solid foundation in C++. More recently I've been working with C# and other higher level languages. A project I'm looking at working on could really benefit from using QT4, but I have some questions on memory management I can't seem to understand. I've read the QT4 documentation ...
Inside of my QGraphicsRectItem::paint(), I am trying to draw the name of the item within its rect(). However, for each of the different items, they can be of variable width and similarly names can be of variable length. Currently I am starting with a maximum font size, checking if it fits and decrementing it until I find a font size th...
I use QT xmlpatterns in XQuery mode to implement templates. The template is an QXmlQuery object and the variables are filled-in using bindVariable(). So far the variables were strings and everything worked fine. Now, I want to inser preformated chunks of XML into the template. I would like to create a piece of xml in C++ using QXmlStr...
I've been trying to use QT4 with a QTableWidget to store data. I seem to be unable to select a cell and get the text out of it and wanted to see why it won't retrieve it. ui->QTableWidget->item(ui->QTableWidget->rowCount(),0)->setText(""); ...
I'm trying to build programmaticaly (with Qt 4.6) a window containing a series of QPushButton's, all packed together. It should look like so (which I call a toolbox): So, I created a Toolbox class, deriving from QWidget, that has the following constructor: Toolbox::Toolbox (void) : QWidget (0, Qt::Tool) { setWindowTitle (tr ("Too...
How can I ignore all mouse and keyboard events and later dont ignore in QT. It is, click a button, ignore all events in childs, click again not ignore. is it clear? I have next lines, but maybe I use in wrong way: setAttribute(Qt::WA_TransparentForMouseEvents); setFocusPolicy( Qt::NoFocus ); thanks, ...
I've tried drawing a rectangle with text inside in a QGraphicsView. I get the text from the currently selected item in a QTreeWidget. The scene seems to sporadically show the text, sometimes it will, sometimes it won't. void MainWindow::on_treewidget_itemSelectionChanged() { drawSectionFromProperties(ui->treewidget->currentItem()); } v...
Hi, i am new to QT, i don't have any knowledge about it. from scratch i need to learn, if you people have some tutorials or some technical blogs please feel free to share with me.. i have seen some stuffs in troltech, tell me any thing else apart from it. Thanks ...
Hi all, I would like to know load finished event of newly injected html 'script' element from Qt. After that i want to call one method of that js file . I am working with Qt UI application. From main method i open the web page. In on_webView_loadFinished() slot , i write script injection first and after that invoke one method from the ...
Hello While developing a Qt Application, I ran into a problem in using QTranslator. After a little research, I found out that the problem was with lupdate from Qt having problem with the using namespace; directive. Following the instructions found in here, I discovered that I have to use special comments in my code, to help lupdate u...
I'm trying to make a simple program consisting of a button and a label. When the button is pressed, it should change the label text to whatever is in a QString variable inside the program. Here's my code so far: This is my widget.h file: class Widget : public QWidget { Q_OBJECT public: Widget(QWidget *parent = 0); ~Widget(...
Hi, I'm using a QWebPage without a QWebView because I want to render the contents of an HTML file onto a QPixmap/QImage. I want the loading of the page to be done synchronously, not asynchronously which is the default. The default way is to call QWebFrame::setHtml() or QWebFrame::setContent(), but this loads images asynchronously. Wha...
I know this is partially subjective, but hopefully with enough specifics I can get a good answer. I am looking to develop an accounting app targeted at a specific market segment (think Quickbooks, but tweaked). Most of the app will be editable tables that are linked with DB data and some basic reporting and graphic functionality. It mu...
I'm writing a simplified calculator using Qt with C++, for learning purposes. Each number is a QPushButton that uses the same slot to modify the text in a lineEdit widget being used as a display. The slot uses the sender() method to figure out which button was pressed, so the correct number would be written on the display widget. In or...
Hi All, I wanted to change the text color of the items in QListWidget. For example, some items are in red text while others are in blue text. How do I do that? Thank you. ...
I want to use OpenCV's image processing functions, but not the OpenCV GUI. I'm using OpenCV 2.0. I will use either Qt4 or WxWidgets for GUI functions. I compile with VC++ 2008 Express (VC++ 9.0). I guess it breaks down to two or three questions: Is it necessary to do something to disable OpenCV's higui so it does not interfere with...