How to disable a button in the slot function?
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you should use repaint in a different manner:
@
void on_button1_clicked()
{
ui->button2->setEnabled(false);
ui->button2->repaint();
// Do something
ui->button2->setEnabled(true);
}
@perhaps then it also works on linux?
You call repaint typically on the widget you want to repaint, not on yourself with a rectangle of a child. This could lead to no repaint (as your own area is hidden behind the child --> no redraw of your widget is needed). -
[quote author="Gerolf" date="1301496355"]you should use repaint in a different manner: @ void on_button1_clicked() { ui->button2->setEnabled(false); ui->button2->repaint(); // Do something ui->button2->setEnabled(true); } @ perhaps then it also works on linux? You call repaint typically on the widget you want to repaint, not on yourself with a rectangle of a child. This could lead to no repaint (as your own area is hidden behind the child --> no redraw of your widget is needed).[/quote]
Thx for your answer!
Dear Gerolf , I tried your code, also, it perform the same way , unless I put a processEvents() behind ui->button2->repaint(); Is it a bug ? -
as per description (and my current usage) repaint should repaint emediatly. In the "docs":http://doc.qt.nokia.com/latest/qwidget.html#repaint there is stated:
[quote]
Repaints the widget directly by calling paintEvent() immediately, unless updates are disabled or the widget is hidden.We suggest only using repaint() if you need an immediate repaint, for example during animation. In almost all circumstances update() is better, as it permits Qt to optimize for speed and minimize flicker.
Warning: If you call repaint() in a function which may itself be called from paintEvent(), you may get infinite recursion. The update() function never causes recursion.
[/quote] -
Couldn't it be a VMWare problem?
I mean, from my own experience with VMWare, sometimes it repaints blocks just like it were a VNC window. And if it is trying to get the window's contents to paint it on the host when the event loop is blocked it might fail.Maybe we should try the same code on a linux host. Unfortunately I don't have it right now.
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Hi All,
If there are some 'N' buttons that need to be disabled with the same scenario,then how that can be achieved? With the complexity that the slots are interconnected with the independent windows.Like button1 click activates an independent window that has a slot to activate another independent window.With the use of modal dialog this can be achieved only between two windows then how about the rest of the active window? -
If you have multiple active windows in your application, and you want a modal dialog that is modal relative to all of them, you need an ApplicationModal dialog box. You can make that by using QDialog::setModel(true) or by using QWidget::setWindowModality(Qt::ApplicationModal).
For disabling and enabling a whole host of widgets in one go, I would change the setup from the last page a bit. Instead of directly disabling and enabling your buttons, I would either simply use signals and slots or use a list of widgets. Using the signal/slot method, you would declare a signal like this:
in the class declaration
@
signals:
void enableButton(bool);
@Then, of course, you need to hookup your buttons to this signal, for instance in your constructor:
@
//make sure this runs once, for instance by putting it in the constructor
connect (this, SIGNAL(enableButton(bool)), m_ui->button1, SLOT(setEnabled(bool)));
connect (this, SIGNAL(enableButton(bool)), m_ui->button2, SLOT(setEnabled(bool)));
connect (this, SIGNAL(enableButton(bool)), m_ui->button3, SLOT(setEnabled(bool)));
//...
connect (this, SIGNAL(enableButton(bool)), m_ui->buttonN, SLOT(setEnabled(bool)));
@In your method, you then do something like this:
@
#include <QApplication>void on_button1_clicked()
{
emit enableButton(false);
QApplication::processEvents(QEventLoop::ExcludeUserInputEvents);
//do other things that may take serveral secondsemit enableButton(true);
}
@ -
Thank You.It works fine so far it is concerned with button1.When I use button2 I want rest of them to be inactive/disabled.But writing the same code repeatedly by making changes for button that is out of group is complicated.
Well I tried with window modality as you have mentioned but still could not get the required result.
Is it possible to check for any active window(by using isActiveWindow) before I click on a button?Thank You
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So, simply disable all buttons like I show above, and re-enable the one button you like to keep enabled?
@
#include <QApplication>void on_button1_clicked()
{
emit enableButton(false);
button1->setEnabled(true);
QApplication::processEvents(QEventLoop::ExcludeUserInputEvents);
//do other things that may take serveral secondsemit enableButton(true);
}void on_button2_clicked()
{
emit enableButton(false);
button2->setEnabled(true);
QApplication::processEvents(QEventLoop::ExcludeUserInputEvents);
//do something else that may also take serveral secondsemit enableButton(true);
}
@There are other solutions, of course.
I don't understand where you're going with your last question. What do you mean that you would like to check what the active window is (what do you mean by that, anyway?) when a button is clicked? That would obviously be the window that button is on then, would it not?