How can i show two windows at same time ? Well i have a mainwindow ,then when i press a button i load a plugin which creates and return a qwidget, and set it as central widget setCentralWidget() ,but my app crashes .If i'm not wrong this anyway will show just one window at same time .
Code from plugin :
QWidget* PlPlugin::initPltter() {
plotter = new QWidget();
plotter->resize(200,300);
plotter->setWindowTitle("mypl");
plotter->show();
return plotter;
}
In my app i'm doing :
setCentralWidget(plotter->initPlotter());
Try not resizing or showing it. Its unnecessary if its going to become a central widget of the mainwindow.
Also, from your example there is nothing suggesting that you are trying to show two windows. What you are doing is creating another widget and setting it as a child of the main window. Do one or the other: Create the widget and show it directly, or create it and parent it under another.
Your MainWindow child shown in main.cpp, for second widget do this:
QWidget* PlPlugin::initPltter() {
plotter = new QWidget();
plotter->resize(200,300);
plotter->setWindowTitle("mypl");
plotter->show();
return plotter;
}
And don't do this
setCentralWidget(plotter->initPlotter());
It allow you to get MainWindow and widget in separate 'window'
Related
If I create and show a top-level QWidget, drag it to a new position on the desktop, then call widget->hide() followed by widget::show(), it generally reappears in a different place from where it was previously.
I can add code to the subclass which saves and restores its geometry, but I'm wondering if there's an in-Qt system for giving hints to the window manager as to where the widget should appear when shown.
Is there a nice way to do this?
I create a "Qt Widgets Application" and drag in a QPushButton, then add the following code:
void Widget::on_pushButton_clicked()
{
hide();
show();
}
Run the program, drag the widget to a new position, and then click on the button and I find that the widget is still in the same place, not like you said
I have a application in Qt, and a MainWindow. Now, I also added a helping QDialog which can be hooked up. This QDialog does not influence the programmflow, it just displays information.
But, it always starts on top of the MainWindow :/
SO I would like to start it on the side of the main window, so that it does not hinder the view to the main window?? How?
In my opinion , You should try this,
Use the overload of the QWidget::setParent() function to change the ownership of a QDialog widget, using set as NULL(but It will not share the parent's taskbar entry).
QDialog::show() returns control to the caller immediately, So it will not interfere in mainwindow flow.
Let's say, your application is in the full screen mode. Where then the QDialog should appear? It will be shown on the top and you won't be satisfied again.
If it doesn't influence the flow of the app then you are using it to communicate some sort of message. Can you use different ways? For instance, QStatusBar?
If not, why not to split the mainWindow with QSplitter or similar classes and provide an area where you can post all the info messages?
It sounds you want modaless dialog. In main window, use a slot to create the dialog.
void MainWindow::show_dialog()
{
if ( pDialog== NULL )
pDialog= new XYZ_Dialog(this);
QPoint p = pos();
QSize s = frameSize();
pDialog->setGeometry(p.x()+s.width(), p.y(), s.width()*1/2, s.height());
pDialog->show();
}
What I try to say is if the position of the new dialog bothers you, you set the position and size of it, before showing it.
Can i have another window over main window in Qt , and how can i implement it? I have a plugin which must return another window. I created in plugin a QWidget and set it as centralWidget but my app crashes.Anyway this will not show two windows at same time . Could someone explain how to do that ?
Any new widget created without a parent will show up as a new window. Don't try to reset 'centralWidget' unless you don't actually want the old one anymore.
If all you want is a main window whose contents change, take a look at StackedWidget.
I have a QGLWidget as part of the UI of my application. It is NOT a central widget, there are a lot of others widgets around it. I want to show it full screen on user clicks the button. Similar functionality like on youtube video flash player.
I have tried to use showFullScreen with no effect.
I have read how-to-fullscreen-a-qglwidget and fullscreen-widget, but they suggest using showFullScreen.
Qt documentation states that for using showFullScreen widget must be an independent window. So I assume there should be some trick for this.
The solution I found:
void MyApp::on_fullscreen_button_clicked() {
QDialog *dlg = new QDialog(this);
QHBoxLayout *dlg_layout = new QHBoxLayout(dlg);
dlg_layout->setContentsMargins(0, 0, 0, 0);
dlg_layout->addWidget(glwidget_);
dlg->setLayout(dlg_layout);
dlg->showFullScreen();
bool r = connect(dlg, SIGNAL(rejected()), this, SLOT(showGlNormal()));
assert(r);
r = connect(dlg, SIGNAL(accepted()), this, SLOT(showGlNormal()));
assert(r);
}
void MyApp::showGlNormal() {
ui.glBox->layout()->addWidget(glwidget_);
}
The showFullScreen function works only on windows. From the Qt documentation:
A window is a widget that isn't visually the child of any other widget
and that usually has a frame and a window title.
A possible solution is the following:
When the user clicks the show full screen button
Create a new QGlWidget with no parent and set to it the contents of you QGlWidget
Use the showFullScreen function on it...
Maybe it is a better idea to subclass QGlWidget and pass in its constructor a pointer to another QGlWidget. The constructor should take the context of the provided widget and apply it to the new one.
On your subclass catch keyboard events. When the user press Esc emit a signal
In your base class catch this signal and connect it to a slot. In this slot hide the full screen QGlWidget and delete it.
when i add the widget to the main window, by default the action menu item will be present,
how to remove that?
menuBar()->setVisible(false);
verAction = new QAction(tr("&Version"),this);
menuBar()->addAction(verAction);
connect(verAction, SIGNAL(triggered()),this, SLOT(displayVersion()));
displayAction = new QAction(tr("&Display"),this);
menuBar()->addAction(displayAction);
connect(displayAction, SIGNAL(triggered()),this, SLOT(displayMessage()));
exitAction = new QAction(tr("&Exit"),this);
menuBar()->addAction(exitAction);
connect(exitAction, SIGNAL(triggered()),this, SLOT(close()));
Thanks
If you want to hide an QAction and display it when you need it, you can use the setVisible function.
If you want to remove the menu bar from the QMainWindow, you can use the QT_NO_MENUBAR preprocessor to remove all uses of a QMenuBar. If you are not using facilities provided by QMainWindow, maybe you can use a simple QWidget as main window in your application.
[Edit]
If you want to hide QActions at runtime, you will find them as member of the QMainWindow's UI. For example if you have a QAction named actionTest, you will access it like that: this->ui->actionTest->setVisible(false);
I know what you mean... you want to HIDE the DEFAULT CONTEXT MENU "Actions"....
You can do this in the Design section (not in code).
Then you see your Object-Stack on the right side like
MainWindow QMainWindow
centralWidget QWidget
webView QWebView
Now go to the property editor below...search for "contextMenuPolicy" and change it from "DefaultContextMenu" to "NoContextMenu" for every component if necessairy.
In order to remove the default context menu with the label "Actions" the following code may be used:
// Remove context menu from the all widgets.
QWidgetList widgets = QApplication::allWidgets();
QWidget* w=0;
foreach(w,widgets) {
w->setContextMenuPolicy(Qt::NoContextMenu);
}
Essentially, the same as the Joel's answer, but the code version :)
(Code taken from QFriendFeed sample from forum.nokia.com)