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  • Qt layout problem.

    - by Lukasz Lew
    I have a following Qt code: QVBoxLayout* box = new QVBoxLayout; label = new QLabel(); // will be set later dynamically box->addWidget (label); Text in label will be set later. The problem is that when label resizes, it resizes QVBoxLayout, and it resizes other neighboring widgets. I don't want to make a label or layout fixed width. Because I want them to resize with a whole window. Is it possible to tell a widget to take all the place that it has in a layout, but not more?

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  • Qt/C++ regular expression library with unicode property support

    - by Dave
    I'm converting an application from the .Net framework to Qt using C++. The application makes extensive use of regular expression unicode properties, i.e. \p{L}, \p{M}, etc. I've just discovered that the QRegExp class lacks support for this among other things (lookbehinds, etc.) Can anyone recommend a C++ regular expression library that: Supports unicode properties Is unicode-aware in other respects (i.e. \w matches more than ASCII word characters) As a bonus, supports lookbehinds. Please don't point me to the wikipedia article; I don't trust it. That article says that QRegExp supports unicode properties. Unless I'm really doing something wrong, it doesn't. I'm looking for someone actually using unicode properties with a regex library in a project.

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  • Analog of Java Form Layout in Qt

    - by Narek
    Once I have programmed GUI with Java and have used Form Layouts. Form layout (if I am not mistaken that is from SWT library) made possible to give right, left, top and bottom adges of any GUI element (widget) with respect to other widgets in the same widget (parent widget) or with respect to the adges of parent widget. So it was possible to control the future of widgets that are inside of another one, when that "another widget" is being resized. In Qt I have find the QFormLayout which is similar to Java one, but seems I can't handle with widgets as flexible in terms of relative positioning, as it was with Java's Form Layout. So are there any other means to give a widget position with respect to the others (without overloading resizeEvent function) as that was in Java? Thanks.

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  • Qt almost same main menu entries

    - by user1671710
    I'm using c++ Qt library and I want to do something which would do : connect(actionB11, SIGNAL(triggered()), this, SLOT(SetSomething(1, 1))); connect(actionB12, SIGNAL(triggered()), this, SLOT(SetSomething(1, 2))); connect(actionB21, SIGNAL(triggered()), this, SLOT(SetSomething(2, 1))); connect(actionB22, SIGNAL(triggered()), this, SLOT(SetSomething(2, 2))); The code above doesnt work because SIGNAL function has to have same number and argument types as SLOT function. Does exist a way how to do it? I dont want to have about 20 function as SetSomething11, SetSomething12 calling SetSomething(1, 1) etc.

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  • QT: trouble with qobject_cast

    - by weevilo
    I have derived QGraphicsItem and QGraphicsScene classes. I want the items to be able to call scene() and get a derviedGraphicsItem * instead of a QGraphicsItem *, so I reimplemented QGraphicsScene::itemAt to return a derived pointer. DerivedItem* DerivedScene::itemAt( const QPointF &position, const QTransform &dt ) const { return qobject_cast< DerivedItem * >( QGraphicsScene::itemAt(position, dt) ); } I get the following error (Qt 4.6, GCC 4.4.3 on Ubuntut 10.4) scene.cpp: In member function ‘DerivedItem* DerivedScene::itemAt(qreal, qreal, const QTransform&) const’: scene.cpp:28: error: no matching function for call to ‘qobject_cast(QGraphicsItem*)’ I then noticed QGraphicsItem doesn't inherit QObject, so I made my derived QGraphicsItem class have multiple inheritance from QObject and QGraphicsItem, and after adding the Q_OBJECT macro and rebuilding the project I get the same error. Am I going about this the wrong way? I know it's supposed to be bad design to try to cast a parent class as a child, but in this case it seems like what I want, since my derived item class has new functionality and its objects need a way to call that new functionality on items around themselves, and asking the items scene object with itemAt() seems like the best way - but I need itemAt() to return a pointer of the right type. I can get around this by having the derived items cast the QGraphicsItem * returned by QGraphicsScene::itemAt() using dynamic_cast, but I don't really understand why that works and not qobject_cast, or the benefits or disadvantages to using dynamic_cast vs. qobject_cast.

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  • Static linking in Qt --> link errors in VS 2008

    - by ChruS
    Today I dediced to make static linking in Qt. I used Qt4 with Visual Studio and static C runtime article. The 3rd step took quite a long time. When it was finished I opened my project in VS 2008, made Build->Clean Solution and try to Release. Unfortunately I got link errors: warning LNK4098: defaultlib 'libcmt.lib' conflicts with use of other libs; use /NODEFAULTLIB:library error LNK2019: unresolved external symbol "private: static struct QString::Data QString::shared_null" (?shared_null@QString@@0UData@1@A) referenced in function "public: __thiscall QString::QString(void)" (??0QString@@QAE@XZ) error LNK2019: unresolved external symbol "private: static struct QByteArray::Data QByteArray::shared_null" (?shared_null@QByteArray@@0UData@1@A) referenced in function "public: __thiscall QByteArray::QByteArray(void)" (??0QByteArray@@QAE@XZ) error LNK2001: unresolved external symbol "private: static struct QByteArray::Data QByteArray::shared_null" (?shared_null@QByteArray@@0UData@1@A) error LNK2001: unresolved external symbol "public: static struct QMetaObject const QDialog::staticMetaObject" (?staticMetaObject@QDialog@@2UQMetaObject@@B) error LNK2001: unresolved external symbol "public: static struct QMetaObject const QDialog::staticMetaObject" (?staticMetaObject@QDialog@@2UQMetaObject@@B) error LNK2001: unresolved external symbol "public: static struct QMetaObject const QDialog::staticMetaObject" (?staticMetaObject@QDialog@@2UQMetaObject@@B) error LNK2019: unresolved external symbol "public: static enum QSysInfo::WinVersion const QSysInfo::WindowsVersion" (?WindowsVersion@QSysInfo@@2W4WinVersion@1@B) referenced in function _WinMain@16 What i did wrong? Help to fix this pls.

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  • Static linking in Qt --> link errors in VS 2008

    - by ChruS
    Today I dediced to make static linking in Qt. I used Qt4 with Visual Studio and static C runtime article. The 3rd step took quite a long time. When it was finished I opened my project in VS 2008, made Build->Clean Solution and try to Release. Unfortunately I got link errors: warning LNK4098: defaultlib 'libcmt.lib' conflicts with use of other libs; use /NODEFAULTLIB:library error LNK2019: unresolved external symbol "private: static struct QString::Data QString::shared_null" (?shared_null@QString@@0UData@1@A) referenced in function "public: __thiscall QString::QString(void)" (??0QString@@QAE@XZ) error LNK2019: unresolved external symbol "private: static struct QByteArray::Data QByteArray::shared_null" (?shared_null@QByteArray@@0UData@1@A) referenced in function "public: __thiscall QByteArray::QByteArray(void)" (??0QByteArray@@QAE@XZ) error LNK2001: unresolved external symbol "private: static struct QByteArray::Data QByteArray::shared_null" (?shared_null@QByteArray@@0UData@1@A) error LNK2001: unresolved external symbol "public: static struct QMetaObject const QDialog::staticMetaObject" (?staticMetaObject@QDialog@@2UQMetaObject@@B) error LNK2001: unresolved external symbol "public: static struct QMetaObject const QDialog::staticMetaObject" (?staticMetaObject@QDialog@@2UQMetaObject@@B) error LNK2001: unresolved external symbol "public: static struct QMetaObject const QDialog::staticMetaObject" (?staticMetaObject@QDialog@@2UQMetaObject@@B) error LNK2019: unresolved external symbol "public: static enum QSysInfo::WinVersion const QSysInfo::WindowsVersion" (?WindowsVersion@QSysInfo@@2W4WinVersion@1@B) referenced in function _WinMain@16 What i did wrong? Help to fix this pls.

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  • Qt QFileDialog - native dialogs only with static functions?

    - by darron
    I'm trying to simply save a file. However, I need a filename entered without a suffix to automatically get a default suffix (which setDefaultSuffix() does). I'd rather not completely lose the native save dialog just for this. exec() is not overloaded from QDialog, so it totally bypasses the native hook (ignoring the DontUseNativeDialog option even if it's false). If I disable the file overwrite warning and append the default suffix myself after the function returns, then I'd be re-opening the dialog if the user did not want to overwrite... and that's just ugly. Is there some signal I can catch and quickly inject the default suffix if it's not there? I'm guessing not, since it's a native dialog. Is there something I'm doing wrong with the filter? I only have one filter choice. It should use that extension. This seems pretty lame. Launching the save dialog and simply typing "test" should never result in an extensionless file. "test.", yes. "test" no way. That'll really confuse the users when they hit Load and can't see the file they just saved. I guess the cross-platform part of Qt is giving me lowest common denominator file dialog functionality?

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  • Qt 5.3 OpenGL - vertex buffer object drawing using the core profile

    - by user3700881
    Im using Qt 5.3 to create a QWindow to do some basic rendering stuff. The QWindow is declared like this: class OpenGLWindow : public QWindow, protected QOpenGLFunctions_3_3_Core { Q_OBJECT ... } It is initialized in the constructor: OpenGLWindow::OpenGLWindow(QWindow *parent) : QWindow(parent) { QSurfaceFormat format; format.setVersion(3,3); format.setProfile(QSurfaceFormat::CoreProfile); this->setSurfaceType(OpenGLSurface); this->setFormat(format); this->create(); _context = new QOpenGLContext; _context->setFormat(format); _context->create(); _context->makeCurrent(this); this->initializeOpenGLFunctions(); ... } And that's the rendering code: void OpenGLWindow::render() { if(!isExposed()) return; _context->makeCurrent(this); glClear(GL_COLOR_BUFFER_BIT); glUseProgram(_shaderProgram); glBindBuffer(GL_ARRAY_BUFFER, _positionBufferObject); glEnableVertexAttribArray(0); glVertexAttribPointer(0, 4, GL_FLOAT, GL_FALSE, 0, 0); glDrawArrays(GL_TRIANGLES, 0, 3); glDisableVertexAttribArray(0); glUseProgram(0); _context->swapBuffers(this); } I am trying to draw a simple triangle using a vertex and fragment shader. The problem is that the triangle is not showing up when the core profile is set. Only when I set the OpenGL version to 2.0 or when I use the compatibility profile, it shows up. From my point of view that doesn't make any sense because I am not using fixed functionality at all. What am I missing?

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  • QT: custom widget in QScrollArea

    - by slimscsi
    I am attempting to create a custom widget. My Widget renders itself unless it is inside a scroll area. The code below works. If I change the if(0) to an if(1) inside the MainWindow constructor, it will not render the "Hello World" string. I assume that I must (re)implement some additional methods, but so far I have not been able to find the correct ones with trial and error. // hellowidget.h #ifndef HELLOWIDGET_H #define HELLOWIDGET_H #include <QtGui> class HelloWidget : public QWidget { Q_OBJECT public: HelloWidget(QWidget *parent = 0); void paintEvent(QPaintEvent *event); }; #endif // HELLOWIDGET_H // hellowidget.cpp #include "hellowidget.h" HelloWidget::HelloWidget(QWidget *parent) : QWidget(parent) { } void HelloWidget::paintEvent(QPaintEvent *event) { QPainter painter(this); painter.drawText(rect(), Qt::AlignCenter, "Hello World"); } // mainwindow.h #ifndef MAINWINDOW_H #define MAINWINDOW_H #include <QtGui> class MainWindow : public QMainWindow { Q_OBJECT public: MainWindow(QWidget *parent = 0); ~MainWindow(); private: }; #endif // MAINWINDOW_H // mainwindow.cpp #include "mainwindow.h" #include "hellowidget.h" MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent) { HelloWidget *hello = new HelloWidget; QWidget *central = hello; if( 0 ) { QScrollArea *scroll = new QScrollArea ; scroll->setWidget(hello); central = scroll; } setCentralWidget( central ); } MainWindow::~MainWindow() { } // main.cpp #include <QtGui/QApplication> #include "mainwindow.h" int main(int argc, char *argv[]) { QApplication a(argc, argv); MainWindow w; w.show(); return a.exec(); }

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  • Custom QAbstractGraphicsShapeItem very slow in Qt Jambi

    - by Mene
    I try to implement an own QAbstractGraphicsShapeItem in Qt Jambi (4.5) but as soon as I implement a custom class (rather than use e.g. QGraphicsEllipseItem) the rendering speed drops by about on order of magnitude. If looked in the original Code of QGraphicsEllipseItem and it seems to do basicly the same. class Circle extends QAbstractGraphicsShapeItem { final private QRectF rect = new QRectF(); public final void setRect(double x, double y, double w, double h) { QRectF newRect = new QRectF(x, y, w, h); if (!newRect.equals(rect)) { prepareGeometryChange(); this.rect.setX(x); this.rect.setY(y); this.rect.setWidth(w); this.rect.setHeight(h); this.update(rect); } } @Override public final QRectF boundingRect() { return rect; } QPainterPath shape; @Override public final QPainterPath shape() { if (shape == null) { QPainterPath path = new QPainterPath(); path.addEllipse(rect); QPainterPathStroker stroker = new QPainterPathStroker(); QPen pen = this.pen(); stroker.setCapStyle(pen.capStyle()); stroker.setWidth(pen.widthF()); shape = stroker.createStroke(path); } return shape; } @Override public final void paint(QPainter painter, QStyleOptionGraphicsItem option, QWidget widget) { painter.setPen(this.pen()); painter.setBrush(this.brush()); painter.drawEllipse(this.rect); } } I need to render a lot of objects and they are mostly moving, so speed is essential. Anyone knows how to speed this up? I underestand that Java might be slower then the nativ code in the library. But the code in the paint method seems not to be the problem, since commenting it out doesn't change the speed notably.

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  • Qt 101: Why can't I use this class?

    - by Airjoe
    I have experience with C++ but I've never really used Qt before. I'm trying to connect to a SQLite database, so I found a tutorial here and am going with that. In the QtCreator IDE, I went to Add New -- C++ Class and in the header file pasted in the header the header from that link and in the .cpp file I pasted the source. My main.cpp looks like this: #include <QtGui/QApplication> #include "mainwindow.h" #include "databasemanager.h" #include <qlabel.h> int main(int argc, char *argv[]) { QApplication a(argc, argv); MainWindow w; w.show(); DatabaseManager db(); QLabel hello("nothing..."); if(db.openDB()){ hello.setText("Win!"); } else{ hello.setText("Lame!"); } hello.resize(100, 30); hello.show(); return a.exec(); } And I'm getting this error: main.cpp:13: error: request for member 'openDB' in 'db', which is of non-class type 'DatabaseManager()' Can anyone point me in the right direction? I know "copypaste" code isn't good, I just wanted to see if I could get DB connectivity working and I figured something like this would be simple... thanks for the help.

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  • WYSIWYG with Qt - font size woes

    - by Rob
    I am creating a custom Qt widget that mimics an A4 printed page and am having problems getting fonts to render at the correct size. My widget uses QPainter::setViewport and QPainter::setWindow to mimic the A4 page, using units of 10ths of a millimetre which enables me to draw easily. However, attempting to create a font at a specific point size doesn't seem to work and using QFont:setPixelSize isn't accurate. Here is some code: View::View(QWidget *parent) : QWidget(parent), printer(new QPrinter) { printer->setPaperSize(QPrinter::A4); printer->setFullPage(true); } void View::paintEvent(QPaintEvent*) { QPainter painter(this); painter.setWindow(0, 0, 2100, 2970); painter.setViewport(0, 0, printer->width(), printer->height()); // Draw a rect at x = 1cm, y = 1cm, 6cm wide and 1 inch high painter.drawRect(100, 100, 600, 254); // Create a 72pt (1 inch) high font QFont font("Arial"); font.setPixelSize(254); painter.setFont(font); // Draw in the same box // The font is too large painter.drawText(QRect(100, 100, 600, 254), tr("Wg\u0102")); // Ack - the actual font size reported by the metrics is 283 pixels! const QFontMetrics fontMetrics = painter.fontMetrics(); qDebug() << "Font height = " << fontMetrics.height(); } So I'm asking for a 254 high font (1 inch, 72 pts) and it's too big and sure enough when I query for the font height via QFontMetrics it is 283 high. Does anyone else know how to use font sizes in points when using custom mapping modes like this? It must be possible. Note that I cannot see how to convert between logical/device points either (i.e. the Win32 DPtoLP/LPtoDP equivalents.)

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  • problem with QPropertyAnimation in Qt

    - by belhaouary
    Hi , i have a problem with QPropertyAnimation in Qt my code: QString my_text = "Hello Animation"; ui->textBrowser->setText((quote_text)); ui->textBrowser->show(); QPropertyAnimation animation2(ui->textBrowser,"geometry"); animation2.setDuration(1000); animation2.setStartValue(QRect(10,220/4,1,1)); animation2.setEndValue(QRect(10,220,201,71)); animation2.setEasingCurve(QEasingCurve::OutBounce); animation2.start(); till now it seems very good , but the problem is that i can see this animation only when i show a message box after it . QMessageBox m; m.setGeometry(QRect(100,180,100,50)); m.setText("close quote"); m.show(); m.exec(); when i remove the code of this message box , i can't see the animation anymore. the functionality of the program doesn't require showing this MessageBox at all. Can anybody help?

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  • creating QT gui using a thread in c++?

    - by rashid
    I am trying to create this QT gui using a thread but no luck. Below is my code. Problem is gui never shows up. /*INCLUDES HERE... .... */ using namespace std; struct mainStruct { int s_argc;<br> char ** s_argv; }; typedef struct mainStruct mas; void *guifunc(void * arg); int main(int argc, char * argv[]) { mas m;<br> m.s_argc = argc;<br> m.s_argv = argv;<br> pthread_t threadGUI; //start a new thread for gui int result = pthread_create(&threadGUI, NULL, guifunc, (void *) &m); if (result) {<br> printf("Error creating gui thread"); exit(0); } return 0; } void *guifunc(void * arg) { mas m = *(mas *)arg; QApplication app(m.s_argc,m.s_argv); //object instantiation<br> guiClass *gui = new guiClass(); //show gui<br> gui->show(); app.exec(); <br> }

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  • Problem with SqlLite database in Qt SDK 1.0.2

    - by Risino
    Hi I have a problem with SqlLite database. Here is my code: void incomeDialog::on_add_pushButton_clicked() { int a = ui->income_lineEdit->text().toInt(); int b = ui->other_lineEdit->text().toInt(); int c = (a+b); db = QSqlDatabase::addDatabase("QSQLITE"); db.setDatabaseName("money.db"); QSqlQuery query(db); query.exec("create table Income" "(Month TEXT, Payment NUMBER, Other NUMBER, Together NUMBER)"); query.prepare("INSERT INTO Income values (?,?,?,?)"); query.addBindValue(ui->comboBox->currentText()); query.addBindValue(ui->income_lineEdit->text().toInt()); query.addBindValue(ui->other_lineEdit->text().toInt()); query.addBindValue(c); query.exec(); } I use qt sdk 1.0.2. After building shows errors: Undefined reference to 'QSqlDatabase::addDatabase(QString const&, QString const&)... all errors is similar (Undefined reference to 'QSqlDatabase:: Do you have any idea how to repair it?

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  • Qtimer not timing out QT, C++

    - by realz
    Hi, I am learning C++ and using QT. I have a small program in which I am trying to update the text of the PushButton every second. The label being current time. I have a timer that should time out every second, but seems like it never does. here's the code. Header File #ifndef _HELLOFORM_H #define _HELLOFORM_H #include "ui_HelloForm.h" class HelloForm : public QDialog { public: HelloForm(); virtual ~HelloForm(); public slots: void textChanged(const QString& text); void updateCaption(); private: Ui::HelloForm widget; }; #endif /* _HELLOFORM_H */ CPP file #include "HelloForm.h" #include <QTimer> #include <QtGui/QPushButton> #include <QTime> HelloForm::HelloForm(){ widget.setupUi(this); widget.pushButton->setText(QTime::currentTime().toString()); widget.pushButton->setFont(QFont( "Times", 9, QFont::Bold ) ); QTimer *timer = new QTimer(this); connect(timer, SIGNAL(timeout()), SLOT(updateCaption())); timer->start(1000); connect(widget.pushButton, SIGNAL(clicked()), qApp, SLOT(quit()) ); connect(widget.nameEdit, SIGNAL(textChanged(const QString&)), this, SLOT(textChanged(const QString&))); } HelloForm::~HelloForm() { } void HelloForm::textChanged(const QString& text) { if (0 < text.trimmed().length()) { widget.helloEdit->setText("Hello " + text.trimmed() + "!"); } else { widget.helloEdit->clear(); } } void HelloForm::updateCaption() { QString myVar; myVar = QTime::currentTime().toString(); widget.pushButton->setText(myVar); } Any help will be greatly appreciated... The PushButton's text never changes...

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  • Using multiple Qt (SQL) Models

    - by radix07
    I have a near real-time application that I am using Qt and an SQLite database to run. I am curious if it is safe to have two separate models access a database at once. I know 2 separate views can access a model just fine, but I can't find any document addressing this. I also realize that SQLite is thread safe for reading, so I don't see a real issue to doing this from the SQLite part of things... Basically I want to use a QSqlTableModel to do the real-time read and write in the background and at the same time use a QSqlQueryModel to give the user desired data. Since I may be doing lots of filtering in the background using the table model I can't use it as the main view as well. I have gotten this to work for the most part, but am not sure if this is the best way to do this. If the models act like multiple SQL queries I don't believe this should be an issue, but I would like to know from someone I bit more knowledgeable about this stuff since this is pretty new to me. Thanks

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  • qT quncompress gzip data

    - by talei
    Hello, I stumble upon a problem, and can't find a solution. So what I want to do is uncompress data in qt, using qUncompress(QByteArray), send from www in gzip format. I used wireshark to determine that this is valid gzip stream, also tested with zip/rar and both can uncompress it. Code so far, is like this: static const char dat[40] = { 0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xaa, 0x2e, 0x2e, 0x49, 0x2c, 0x29, 0x2d, 0xb6, 0x4a, 0x4b, 0xcc, 0x29, 0x4e, 0xad, 0x05, 0x00, 0x00, 0x00, 0xff, 0xff, 0x03, 0x00, 0x2a, 0x63, 0x18, 0xc5, 0x0e, 0x00, 0x00, 0x00 }; //this data contains string: {status:false}, in gzip format QByteArray data; data.append( dat, sizeof(dat) ); unsigned int size = 14; //expected uncompresed size, reconstruct it BigEndianes //prepand expected uncompressed size, last 4 byte in dat 0x0e = 14 QByteArray dataPlusSize; dataPlusSize.append( (unsigned int)((size >> 24) & 0xFF)); dataPlusSize.append( (unsigned int)((size >> 16) & 0xFF)); dataPlusSize.append( (unsigned int)((size >> 8) & 0xFF)); dataPlusSize.append( (unsigned int)((size >> 0) & 0xFF)); QByteArray uncomp = qUncompress( dataPlusSize ); qDebug() << uncomp; And uncompression fails with: qUncompress: Z_DATA_ERROR: Input data is corrupted. AFAIK gzip consist of 10 byte header, DEFLATE peyload, 12 byte trailer ( 8 byte CRC32 + 4 byte ISIZE - uncompresed data size ). Striping header and trailer should leave me with DEFLATE data stream, qUncompress yields same error. I checked with data string compressed in PHP, like this: $stringData = gzcompress( "{status:false}", 1); and qUncompress uncompress that data.(I didn't see and gzip header though i.e. ID1 = 0x1f, ID2 = 0x8b ) I checked above code with debug, and error occurs at: if ( #endif ((BITS(8) << 8) + (hold >> 8)) % 31) { //here is error, WHY? long unsigned int hold = 35615 strm->msg = (char *)"incorrect header check"; state->mode = BAD; break; } inflate.c line 610. I know that qUncompress is simply a wrapper to zlib, so I suppose it should handle gzip without any problem. Any comments are more then welcome. Best regards

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  • Insane CPU usage in QT 5.0

    - by GravityScore
    I'm having trouble using the QT framework, particularly with the paintEvent of QWidget. I have a QWidget set up, and am overriding the paintEvent of it. I need to render a bunch of rectangles (grid system), 51 by 19, leading to 969 rectangles being drawn. This is done in a for loop. Then I also need to draw an image on each on of these grids. The QWidget is added to a QMainWindow, which is shown. This works nicely, but it's using up 47% of CPU per window open! And I want to allow the user to open multiple windows like this, likey having 3-4 open at a time, which puts the CPU close to 150%. Why does this happen? Here is the paintEvent contents. The JNI calls don't cause the CPU usage, commenting them out doesn't lower it, but commenting out the p.fillRect and Renderer::renderString (which draws the image) lowers the CPU to about 5%. // Background QPainter p(this); p.fillRect(0, 0, this->width(), this->height(), QBrush(QColor(0, 0, 0))); // Lines for (int y = 0; y < Global::terminalHeight; y++) { // Line and color method ID jmethodID lineid = Manager::jenv->GetMethodID(this->javaClass, "getLine", "(I)Ljava/lang/String;"); error(); jmethodID colorid = Manager::jenv->GetMethodID(this->javaClass, "getColorLine", "(I)Ljava/lang/String;"); error(); // Values jstring jl = (jstring) Manager::jenv->CallObjectMethod(this->javaObject, lineid, jint(y)); error(); jstring cjl = (jstring) Manager::jenv->CallObjectMethod(this->javaObject, colorid, jint(y)); error(); // Convert to C values const char *l = Manager::jenv->GetStringUTFChars(jl, 0); const char *cl = Manager::jenv->GetStringUTFChars(cjl, 0); QString line = QString(l); QString color = QString(cl); // Render line for (int x = 0; x < Global::terminalWidth; x++) { QColor bg = Renderer::colorForHex(color.mid(x + color.length() / 2, 1)); // Cell location on widget int cellx = x * Global::cellWidth + Global::xoffset; int celly = y * Global::cellHeight + Global::yoffset; // Background p.fillRect(cellx, celly, Global::cellWidth, Global::cellHeight, QBrush(bg)); // String // Renders the image to the grid Renderer::renderString(p, tc, text, cellx, celly); } // Release Manager::jenv->ReleaseStringUTFChars(jl, l); Manager::jenv->ReleaseStringUTFChars(cjl, cl); }

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  • Qt Linker Errors

    - by Kyle Rozendo
    Hi All, I've been trying to get Qt working (QCreator, QIde and now VS2008). I have sorted out a ton of issues already, but I am now faced with the following build errors, and frankly I'm out of ideas. Error 1 error LNK2019: unresolved external symbol "public: void __thiscall FileVisitor::processFileList(class QStringList)" (?processFileList@FileVisitor@@QAEXVQStringList@@@Z) referenced in function _main codevisitor-test.obj Question1 Error 2 error LNK2019: unresolved external symbol "public: void __thiscall FileVisitor::processEntry(class QString)" (?processEntry@FileVisitor@@QAEXVQString@@@Z) referenced in function _main codevisitor-test.obj Question1 Error 3 error LNK2019: unresolved external symbol "public: class QString __thiscall ArgumentList::getSwitchArg(class QString,class QString)" (?getSwitchArg@ArgumentList@@QAE?AVQString@@V2@0@Z) referenced in function _main codevisitor-test.obj Question1 Error 4 error LNK2019: unresolved external symbol "public: bool __thiscall ArgumentList::getSwitch(class QString)" (?getSwitch@ArgumentList@@QAE_NVQString@@@Z) referenced in function _main codevisitor-test.obj Question1 Error 5 error LNK2019: unresolved external symbol "public: void __thiscall ArgumentList::argsToStringlist(int,char * * const)" (?argsToStringlist@ArgumentList@@QAEXHQAPAD@Z) referenced in function "public: __thiscall ArgumentList::ArgumentList(int,char * * const)" (??0ArgumentList@@QAE@HQAPAD@Z) codevisitor-test.obj Question1 Error 6 error LNK2019: unresolved external symbol "public: __thiscall FileVisitor::FileVisitor(class QString,bool,bool)" (??0FileVisitor@@QAE@VQString@@_N1@Z) referenced in function "public: __thiscall CodeVisitor::CodeVisitor(class QString,bool)" (??0CodeVisitor@@QAE@VQString@@_N@Z) codevisitor-test.obj Question1 Error 7 error LNK2001: unresolved external symbol "public: virtual struct QMetaObject const * __thiscall FileVisitor::metaObject(void)const " (?metaObject@FileVisitor@@UBEPBUQMetaObject@@XZ) codevisitor-test.obj Question1 Error 8 error LNK2001: unresolved external symbol "public: virtual void * __thiscall FileVisitor::qt_metacast(char const *)" (?qt_metacast@FileVisitor@@UAEPAXPBD@Z) codevisitor-test.obj Question1 Error 9 error LNK2001: unresolved external symbol "public: virtual int __thiscall FileVisitor::qt_metacall(enum QMetaObject::Call,int,void * *)" (?qt_metacall@FileVisitor@@UAEHW4Call@QMetaObject@@HPAPAX@Z) codevisitor-test.obj Question1 Error 10 error LNK2001: unresolved external symbol "protected: virtual bool __thiscall FileVisitor::skipDir(class QDir const &)" (?skipDir@FileVisitor@@MAE_NABVQDir@@@Z) codevisitor-test.obj Question1 Error 11 fatal error LNK1120: 10 unresolved externals ... \Visual Studio 2008\Projects\Assignment1\Question1\Question1\Debug\Question1.exe Question1 The code is as follows: #include "argumentlist.h" #include <codevisitor.h> #include <QDebug> void usage(QString appname) { qDebug() << appname << " Usage: \n" << "codevisitor [-r] [-d startdir] [-f filter] [file-list]\n" << "\t-r \tvisitor will recurse into subdirs\n" << "\t-d startdir\tspecifies starting directory\n" << "\t-f filter\tfilename filter to restrict visits\n" << "\toptional list of files to be visited"; } int main(int argc, char** argv) { ArgumentList al(argc, argv); QString appname = al.takeFirst(); /* app name is always first in the list. */ if (al.count() == 0) { usage(appname); exit(1); } bool recursive(al.getSwitch("-r")); QString startdir(al.getSwitchArg("-d")); QString filter(al.getSwitchArg("-f")); CodeVisitor cvis(filter, recursive); if (startdir != QString()) { cvis.processEntry(startdir); } else if (al.size()) { cvis.processFileList(al); } else return 1; qDebug() << "Files Processed: %d" << cvis.getNumFiles(); qDebug() << cvis.getResultString(); return 0; } Thanks in advance, I'm simply stumped.

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  • How do I toggle 'always on top' for a QMainWindow in Qt?

    - by Jake Petroules
    void MainWindow::on_actionAlways_on_Top_triggered(bool checked) { Qt::WindowFlags flags = this->windowFlags(); if (checked) { this->setWindowFlags(flags | Qt::CustomizeWindowHint | Qt::WindowStaysOnTopHint); this->show(); } else { this->setWindowFlags(flags ^ (Qt::CustomizeWindowHint | Qt::WindowStaysOnTopHint)); this->show(); } } The above solution works but because setWindowFlags hides the window, it needs to be re-shown and of course that doesn't look very elegant. So how do I toggle "always on top" for a QMainWindow without that "flashing" side effect?

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  • Windows DD-esque implementation in Qt 5

    - by user1777667
    I'm trying to get into Qt and as a project I want to try and pull a binary image from a hard drive in Windows. This is what I have: QFile dsk("//./PhysicalDrive1"); dsk.open(QIODevice::ReadOnly); QByteArray readBytes = dsk.read(512); dsk.close(); QFile img("C:/out.bin"); img.open(QIODevice::WriteOnly); img.write(readBytes); img.close(); When I run it, it creates the file, but when I view it in a hex editor, it says: ëR.NTFS ..........ø..?.ÿ.€.......€.€.ÿç......UT..............ö.......ì§á.Íá.`....ú3ÀŽÐ¼.|ûhÀ...hf.ˈ...f.>..NTFSu.´A»ªUÍ.r..ûUªu.÷Á..u.éÝ..ƒì.h..´HŠ...‹ô..Í.ŸƒÄ.žX.rá;...uÛ£..Á.....Z3Û¹. +Èfÿ.......ŽÂÿ...èK.+Èwï¸.»Í.f#Àu-f.ûTCPAu$.ù..r..h.».hp..h..fSfSfU...h¸.fa..Í.3À¿(.¹Ø.üóªé_...f`..f¡..f.....fh....fP.Sh..h..´BŠ.....‹ôÍ.fY[ZfYfY..‚..fÿ.......ŽÂÿ...u¼..faàø.è.. û.è..ôëý´.‹ð¬<.t.´.»..Í.ëòÃ..A disk read error occurred...BOOTMGR is missing...BOOTMGR is compressed...Press Ctrl+Alt+Del to restart...Œ©¾Ö..Uª Is there a better way of doing this? I tried running it as admin, but still no dice. Any help would be much appreciated. Update: I changed the code a bit. Now if I specify a dd images as the input it writes the image perfectly, but when I try to use a disk as the input it only writes 0x00. QTextStream(stdout) << "Start\n"; QFile dsk("//./d:"); //QFile dsk("//./PhysicalDrive1"); //QFile dsk("//?/Device/Harddisk1/Partition0"); //QFile dsk("//./Volume{e988ffc3-3512-11e3-99d8-806e6f6e6963}"); //QFile dsk("//./Volume{04bbc7e2-a450-11e3-a9d9-902b34d5484f}"); //QFile dsk("C:/out_2.bin"); if (!dsk.open(QIODevice::ReadOnly)) qDebug() << "Failed to open:" << dsk.errorString(); qDebug() << "Size:" << dsk.size() << "\n"; // Blank out image file QFile img(dst); img.open(QIODevice::WriteOnly); img.write(0); img.close(); // Read and write operations while (!dsk.atEnd()) { QByteArray readBytes = dsk.readLine(); qDebug() << "Reading: " << readBytes.size() << "\n"; QFile img(dst); if (!img.open(QIODevice::Append)) qDebug() << "Failed to open:" << img.errorString(); img.write(readBytes); } QTextStream(stdout) << "End\n"; I guess the real problem I'm having is how to open a volume with QFile in Windows. I tried a few variants, but to no avail.

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