Custom DelayButton background not changing

MiklYarochkin

Hello,

I need to make a PushButton with delayed activation: press during 1 sec-> checked.

To indicate activation progress to the user, I am trying to use QProxyStyle: for example, change color from lighter to darker every 100ms.

But it is not working even in a simple form:

...
ui.DelayButtonDemo->setStyle(new DelayButtonStyle);
...

class DelayButtonStyle : public QProxyStyle
{
 void drawControl(ControlElement element, const QStyleOption* option, QPainter* painter, const QWidget* widget) const
 {
     QPushButton* currentDelayButton = (QPushButton*)widget;

     if (currentDelayButton->isDown() == true)
     {
         QStyleOptionButton buttonOption(*qstyleoption_cast<const QStyleOptionButton*>(option));

         buttonOption.palette.setColor(QPalette::Button,
             QColor(Qt::red));

         QProxyStyle::drawControl(element, &buttonOption, painter, widget);

         return;
     }

     QProxyStyle::drawControl(element, option, painter, widget);
 }
}

Can you help me please to find mistake?

J.Hilk

@MiklYarochkin in such cases, it's most likely a blocked event loop

how do you call this function?

can you show that?

MiklYarochkin

Hello,

Thank you for your fast reaction.

I updated my code snippet.

Don't think the loop is blocked.
This function is called correctly.
As an experiment, I was trying to play with text color, and I see a change of color:
QPalette::Button -> QPalette::ButtonText

...
buttonOption.palette.setColor(QPalette::ButtonText,
            QColor(Qt::red));
...

I found this:
https://doc.qt.io/qt-5/stylesheet-reference.html
Warning: If you only set a background-color on a QPushButton, the background may not appear unless you set the border property to some value. This is because, by default, the QPushButton draws a native border which completely overlaps the background-color. For example,

Could it be a reason?

But I don't know how to set it in drawControl
If I set border using setStyleSheet, it stops working completely.

J.Hilk

@MiklYarochkin I see, this, is sadly out of my scope of experience 😔
Hopefully someone else can help you here!

Could it be a reason?

Sounds like it could very well be the reason!

mrjj

@MiklYarochkin said in Custom DelayButton background not changing:

QStyleOptionButton

Hi
You can see here what drawControl really does

https://code.woboq.org/qt5/qtbase/src/widgets/styles/qcommonstyle.cpp.html#1321
(and in fusion style/for your platform)

I did try to copy the code and add brushes etc in my delegate but i was not able to change the background but
you might have better luck :)

MiklYarochkin

I finally made it:
in order to operate color, I have to overrule standard behavior

set full set of styles using setStyleSheet
handle events
manage flow

And I gave up to use it at the end:

a lot of custom code with a doubtful outcome
ugly design
not clear flow

Solution:
I use the standard functionality of the standard button. Better explain to the user what "it works and feels the same as all other buttons in Windows"

Solved Custom DelayButton background not changing