My application has non-rectangular popup widgets.
their class defines the following to achieve that transparency:
setAttribute(Qt::WA_NoSystemBackground, true);
setAttribute(Qt::WA_TranslucentBackground, true);
I also use:
this->setWindowFlags(Qt::Popup| Qt::FramelessWindowHint);
The problem is that on windows 7, an automatic "shadow" is being drawn on the bottom and right sides of my window. This is highly undesirable.
So, I tried using Qt::Tool instead of Qt::Popup
this->setWindowFlags(Qt::Tool | Qt::FramelessWindowHint);
This works visually. No shadow, but now a mouse click outside my widget window will not automatically close/hide it as it would have done with a Qt::Popup.
So, I need one of these two solutions:
A way to have Qt::Popup and get rid of that automatic windows shadow decoration
A way to let the Qt::Tool window a mouse click occurred outside of it.
One note: My application is built for Windows XP and up. I cannot use a Vista/Win7 only runtime DLLs, nor can i have a "Windows XP" and "Vista and up" separate builds.
Any advice will be welcome.
You could manually watch for when the focus changes from your Qt::Tool window. So basically you watch for when the focus goes onto another window of your process or when your application loses focus.
How to detect that my application lost focus in Qt?
Hope that helps.
Finally after realizing that no amount of "SetFocusPolicy" calls will allow me to receive those events for a Qt::Tool window, I've resorted to something else to fix my problem:
I kept the Qt:tool as Qt::Popup caused an undesired shadowing effect, tarnishing my owner draw frame. Removing this style cannot be done in Qt and I didn't want to mess with platform specific conditional code.
I installed an event filter with my Qt::tool window and I began receiving events that assisted me in understanding when other parts of my application were clicked, or if the application itself lost focus to another application. This was what I needed, functionality wise. I could also get an event when users click the non-client areas of the application's main window, such as the windows caption so that I can close it when dragging begins etc.
My solution for Windows 7:
QDialog *d = new QDialog;
d->setStyleSheet("background:transparent;");
d->setAttribute(Qt::WA_DeleteOnClose, true);
d->setAttribute(Qt::WA_TranslucentBackground, true);
#ifdef Q_OS_WIN
d->createWinId();
#endif
d->setWindowFlags(Qt::Popup | Qt::FramelessWindowHint);
d->show();
I set my QListView
d->setWindowFlags(Qt::Popup | Qt::FramelessWindowHint);
Install eventfilter and used MousePressEvent to hide qlistview widget.
MousePressEvent on list never comes to filter they produce other events which I didn't debug.
So if you want to design auto completer this will be perfect. Tested in Qt5.3.1.
Related
I have a C++ Qt 4 application written for Raspberry Pi. I'm experiencing an odd side-effect of showing a QMessageBox and I don't know enough about Qt to debug it.
The pi has a touchscreen, so I launch the application with unclutter to hide the mouse cursor. (Though this doesn't affect my issue... I have tried without unclutter just in case.)
I have sub-classed QLineEdit to override focusInEvent() and focusOutEvent() to select-all when a LineEdit gets focus, and deselect-all when it loses focus.
Before showing any QMessageBoxes, everything works perfectly - tapping on a QLineEdit selects all the text; tapping the next one de-selects the previous QLineEdit, and selects the new QLineEdit.
After showing a QMessageBox, my overridden events stop working, and QLineEdits no longer auto-select and de-select.
If I add:
msgBox.setWindowFlags(msgBox.windowFlags() | Qt::Popup);
before I exec() the QMessageBox, then text highlighting continues working normally, but the cursor is displayed and flickers while the QMessageBox is on the screen.
It seems like there is a side-effect of showing the QMessageBox that affects the calling window and my sub-classed QLineEdit boxes... but not if the QMessageBox has the Popup flag set!
I've tried storing and manually re-loading the flags on the main window, and that does nothing, so it doesn't appear to be flags on the main window.
One more oddity: everything works fine if I run the application remotely over XMing and SSH... it's only when it's run locally on the Pi in plain-old X11 that it freaks out.
Any thoughts on how to debug this? Thank you!
I was able to work around this by doing two things.
First, I updated the flags of the QMessageBox before opening it:
msgBox.setWindowFlags(Qt::Popup);
msgBox.exec();
and second, I hid the cursor in Qt code, rather than relying on Unclutter; this fixed the flickering cursor issue:
QApplication::setOverrideCursor(Qt::BlankCursor);
Going up the learning curve and everything has been making sense so far except for this one:
I have a main window from where I call one or more dialog like this:
d->setWindowFlags(Qt::CustomizeWindowHint | Qt::Window | Qt::FramelessWindowHint);
d->setGeometry(etc...
d->show();
The dialogs are not bound to the main window, and they are actually set to be displayed right beside the main window looking like an extension.
To close the dialogs I use a mouse 'enterEvent' on the mainwindow to send a close signal to the dialog(s) which will use hide().
void MainWidget::enterEvent(QEvent *event)
{
emit signal_related_close();
}
This works but randomly this causes a very annoying issue. When the signal is sent to close the dialogs, the main window would loose focus and go in the background (behind whatever application that is on the screen). Note that it does not minimize but only goes in the background and like I said it is random (about one out of 3 times I do it). I can't seem to get a pattern.
I initially thought the signal was messed up and instead used a dialog::leaveEvent() but that didn't help. I also tried using dialog::mouseMoveEvent and using that to hide the dialog but that would still randomly loose focus on the application.
The only method that doesn't loose focus is using a push button on each dialog that will initiate the same hide commands but that's not great for my UI. So it would seem that using the mouse enterEvent/leaveEvent,mouseMoveEvent will cause that random issue.
Anyone experienced this issue before? Any idea what could be wrong? Thx.
I can't explain why but this problem occurred when using QEvent or any mouse related event together with recursive children widgets. For example take this code in the parent widget constructor:
ChildWidget c1 = new ChildWidget (this);
ChildWidget c2 = new ChildWidget (c1);
Childwidget c3 = new ChildWidget (c2);
Using QEvent in the parent widget will randomly make the window go to the background and loose focus.
Setting all the ChildWidget to the same parent stopped the problem.
I have a QDialog that was created with Qt::WA_DeleteOnClose flag. When specific event happens I need to hide the dialog and restore it later upon another specific event. If I make a call to QWidget::hide() the dialog object is deleted (due to WA_DeleteOnClose) which doesn't work for me.
Unfortunately I can't unset/reset Qt::WA_DeleteOnClose in runtime for certain technical reasons.
The question is: how do I effectively hide QDialog so that it's not visible but still exists? I tried
QDialog* pDlg = ...;
QSizePolicy newSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
pDlg->setSizePolicy(newSizePolicy);
pDlg->setMinimumSize(0,0);
pDlg->resize(0,0);
but this didn't work. Might it be that I can move the dialog outside the desktop? Or...
I'm solely on Windows if it matters.
Thanks.
I have a main window (on MS Windows) and I want to have sub windows or subpanels with free screen movement. I can use dialog and Qt::splashscreen flag, but when I am on these subwindows I lose the focus caption for the main window. Is there any trick to do what I want? (Something like a multi-focus...)
Maybe it is impossible?
I'm not sure what you mean by losing the focus.
When I create an application with multiple windows, this is what I do: in the sub-window widget, I set the parent to the main window, and set the Qt::Tool flag. It has multiple effects: the window manager sees it as one window, and when you focus any window, all the windows raise.
Do you want QMdiArea? Or a focus proxy?
In Qt, all top-level windows are independent, none is the "main". If you want to nominate one as a main window and have it steal focus from the others, then you will have to implement that manually.
Sounds like you just want to have widgets that you can move around freely on a parent widget/window, without invoking the "window focus changed" event between native Windows windows (...).
I'm not sure if there is a ready-made solution for that, but adding some grab/move/resize events to a widget's edges shouldn't be that hard, or?
I'd simply catch mousedown/up events on certain areas (these should probably be widgets of their own with a link to the parent movable widget), and have them resize/move the window when the mouse moves.
I use the last Qt version for a projet and QProcess. I want to lauch program from my application by using QProcess. I want to display a QGraphicsView transparent on full screen over the launched program.
For the moment: I hide the view, launch the program, sleep during 5 seconds and show the view. I want that my view keep the focus and stay on the top level? Is there any better way to do that? A custom setting for the QGraphicsView?
Create your QGraphicsView (or the window that contains it) with the Qt::WindowStaysOnTopHint flag
Once you run a program in QProcess, you have limited control over it. Qt does not provide details about other applications that are running, you won't know where the launched application is being displayed unless it tells you explicitly.
If you have access to the code of the application you're running, it is possible put a transparent overlay on top a given widget, or widgets, that could then record mouse clicks and other interactions. It's also possible to override events and record basic information about the application's use.