I have a Qt form, where I have a button and menu. For various reasons I can disable certain elements, e.g button or some actions in the menu.
Is there a way I could show a tooltip or when the mouse is hovered over the disabled button or menu item with an explanation as to why it is disabled?
I am using Qt 4.8.
Thanks!
You can set the tooltip dynamically based on the state of the QWidget or by simply toggling both at the same time. Upon disabling/enabling the widget from somewhere just call QWidget::setToolTip(...) with the QString you want the tooltip to display when hovering with the mouse over the given widget. For example if you have a public slot called toggleButton(bool toggleFlag) which toggles the enable-setting of a button you can do:
void MyWidget::toggleButton(bool toggleFlag) {
this->ui->myButton->setEnabled(toggleFlag);
this->ui->myButton->setToolTip(toggleFlag ? QString("Enabled wohoo!") : QString("Disabled because I like it"));
}
You can of course do also change the tooltip by calling QWidget::isEnabled() and act upon its return value. Since you haven't given any code I can only assume how you toggle your button(s) so that's all I can give you for now.
UPDATE: It was pointed in the comments that tooltips don't work with disabled widgets due not receiving mouse events. Both statements are not true (note that I have used the same tooltip message since due to lack of minimal working example I didn't want to write a whole new project from scratch and used an existing one of mine instead):
Hovering a disabled button triggers the tooltip
Hovering an enabled button triggers the tooltip
Related
There is a QGroupBox full of widgets, and all of them need to be disabled and grayed out.
setDisabled(true) does disable them functionally, but they don't turn gray.
What is the easiest and most proper way to turn them gray?
This should be a standard operation: text turns gray so that users can easily see that they are disabled.
QWidget::setDisabled() is yet (another) slot for the QWidget enabled property.
From Qt doc.:
This property holds whether the widget is enabled
In general an enabled widget handles keyboard and mouse events; a disabled widget does not. An exception is made with QAbstractButton.
Some widgets display themselves differently when they are disabled. For example a button might draw its label grayed out.
(Emphasizing by me.)
How widgets are displayed depends on their respective rendering as well as the (default) QStyle which is used in the application.
Concerning custom widgets (classes derived from any "built-in" Qt widget) where paintEvent() is overloaded, the custom widget is itself responsible to render accordingly to different states.
I have a readonly QTextEdit. I'm able to select the text and copy it.
What I need to do: When the user is in selection mode(selecting text), if he leaves the area (with the left mouse button still holding) the widget must lose focus and selection focus must end too. When mouse exits out of bounds I want to be similar to mouse release. I tried to set this:
rootWidget->clearFocus();
rootWidget->close();
rootWidget->releaseMouse();
but even though visually the widget seems out of focus I still receive the TextEdit::mouseMoveEvent() of my widget.
I also tried to set focus to a dummy widget. The dummy widget gets focused but my textedit sitll gets mouseMoveEvent().
How can I lose focus of the widget completely without releasing the mouse button?
Thank you for any suggestion!
You can give the focus to something else using QWidget::setFocus(). you should probably clear the selection before changing focus.
I have a Qt application in which certain QLabel's display a tooltip if a certain internal condition occurs.
Since the tooltip has a timeout and is hidden by Qt automatically, the tooltip is kept alive by the application by showing the tooltip every 3 seconds (I did not find any mechanism to tell Qt to show a tooltip indefinitely).
The tooltip is displayed until the user clicks on the QLabel itself: the tooltip is not refreshed any more and disappears.
I now have a new requirement that the tooltip should also disappear if the user clicks on the tooltip itself. Is there a signal that is sent when the user clicks on a visible tooltip? Or is it necessary to use some more sophisticated technique?
EDIT
I have checked my code again, here is some extra information.
Qt does detect a mouse click on a tooltip and hides it, but the application immediately shows the tooltip again.
What I would like to do is that Qt informs my code of the mouse-clicked event, so that it stops showing the tooltip again and again. I have two possible solutions in mind, but I do not know if either of them is technically feasible:
Remove tooltip timeout: when a tooltip is shown, it remains visible as long as the user does not click on it. How can I display a tooltip without a timeout in Qt?
Keep the tooltip visible by repeatedly showing it; detect a mouse clicked on the tooltip in order to stop the keep-alive loop. How do I receive a signal when the user clicks on a tooltip?
Under the hood, the actual class that implements the tooltip is a private QLabel-derived class called QTipLabel:
http://qt.gitorious.org/qt/qt/blobs/4.7/src/gui/kernel/qtooltip.cpp#line119
There's nothing published in the interface to get at an instance of that class from QToolTip, so intercepting clicks would only be done with some sort of ill-advised hack.
That said: among the events that should "hideTipImmediately" is QEvent::mouseButtonPress...in fact, there's an event filter installed so that any click in the app will hide it:
http://qt.gitorious.org/qt/qt/blobs/4.7/src/gui/kernel/qtooltip.cpp#line325
So if you're not seeing the tooltip disappear when it's being clicked on, there's a bug. (Clicking on tooltips hides them for me in Qt-based apps under Kubuntu.)
Note the definition of QToolTip::showText:
void QToolTip::showText ( const QPoint & pos, const QString & text,
QWidget * w, const QRect & rect ) [static] Shows text as a tool tip,
with the global position pos as the point of interest. The tool tip
will be shown with a platform specific offset from this point of
interest.
If you specify a non-empty rect the tip will be hidden as soon as you
move your cursor out of this area.
The rect is in the coordinates of the widget you specify with w. If
the rect is not empty you must specify a widget. Otherwise this
argument can be 0 but it is used to determine the appropriate screen
on multi-head systems.
If text is empty the tool tip is hidden. If the text is the same as
the currently shown tooltip, the tip will not move. You can force
moving by first hiding the tip with an empty text, and then showing
the new tip at the new position.
Thus, you can supply the rectangle in which the QToolTip is to be presented. Then, if what you want to do is close the QToolTip only when the user clicks on it, you can capture mouseButtonPress events as #HostileFork pointed out and then close the tooltip only when the coordinates of the event fall within it.
I'm working on a custom Qt button that allows you to edit the text on the button if you double click it. When the button is double clicked, a QLineEdit appears where the text on the button is allowing the user to edit the text on the button. My requirement is that if the user clicks anywhere in the application window, the QLineEdit should disappear and cancel the edit operation. This works in some cases. Specifically, it works if I click on anything that is capable of text entry. Other portions of the window don't work as expected. I'll click on a blank portion of the application window, and the QLineEdit retains its focus. How can I remove its focus in these cases?
I've found a solution that seems to work, though I'm still open to other options if there are any. I'm using PyQt4, so my example is in python:
Create a subclass of QLineEdit just so I have a new type. I don't want or need this behavior on all QLineEdit instances; just these specific ones.
class MyLineEdit(QtGui.QLineEdit):
pass
Now, in my QMainWindow subclass, I override the mousePressEvent() implementation. It gets the currently focused widget. If that widget is of type MyLineEdit, clear the focus.
class MyMainWindow(QtGui.QMainWindow):
def ...
def mousePressEvent(self, event):
focused_widget = QtGui.QApplication.focusWidget()
if isinstance(focused_widget, MyLineEdit):
focused_widget.clearFocus()
QtGui.QMainWindow.mousePressEvent(self, event)
def ...
This gets me the behavior I'm looking for so that if the user clicks anywhere on the application's window, the focus is cleared.
Edit: I did find one caveat to this. I have a QTreeView in the main window. If the user clicks on the tree view, focus is not removed from the text edit field.
Catch the clicked() signal of your parent widget and call yourLabel->clearFocus() (that unfortunatelly happens to not be a slot, making things more complicated) there.
I followed Grant Limberg instruction here but figured out that, in my case, a simple:
QApplication.focusWidget().clearFocus()
would fix the problem.
I'm not sure if this also works in Qt4 (I'm using PyQt5) but you can change the FocusPolicy of the QMainWindow or parent widget to clear the focus in the QLineEdit. As per https://doc.qt.io/qt-5/qwidget.html#focusPolicy-prop
I've changed the policy of my QMainWindow to Qt.StrongFocus and it worked like the functionality described in the question.
If done in C++ I would do something along the lines of:
connect(myWidgets->MyLineEdit, SIGNAL(returnPressed()), this, SLOT(onLineEditDone());
void onLineEditDone()
{
myWidgets->MyLineEdit->clearFocus();
}
For this particular case I would use editingFinished() instead of returnPressed(), probably, but I would NOT use textChanged(QString).
In my flex app I have custom tooltips on buttons that hide and show based on user context.
The problem that I dealing with is that when I call my showTips() function I only want to show tooltips on the buttons that visible in the view. So buttons that on a un-selected tab (tabNavigator) should not show the tooltips.
For some reason all tooltips are showing.
Is there a way to detect if a button is not in current view, like on a un-selected tab?
If you gave us some code I could check this out, but would this work?
if(button.parent.visible) { showTip(button);}
Instead of custom coding for each button, make use your tabnavigator's creation policy is set to "auto".
Check this link for more details
http://livedocs.adobe.com/flex/3/html/help.html?content=layoutperformance_05.html