Subclassing QSlider with handle as a Widget
-
Yes, is perfectly doable by subclassing QSlider.
See my slider implementation for example :
!http://s22.postimg.org/4c9p4p0qp/Slider.png(my Slider)!The two green areas are two QLabels
edit: Andre was faster :-)
-
Thank you very much for your answers.
I want to have the behaviour of a slider I just want the handle to be a rectangle widget to draw whatever I want inside.Looks like your example is perfect cincirin, could you please tell me with 2 lines of codes how you acheieved that?
Can you move these two QLabels?
I cant figure how to access the handle by the QSlider class .... -
bq. could you please tell me with 2 lines of codes how you acheieved that?
Of course I can, but as Andre said is better to tell us what are you trying to achieve and what are your attempts to implement them ?
bq. Can you move these two QLabels?
Yes any widget can be moved, just set the widget position depending on your requirements.
So in short here is my implementation:
-
- subclass QSlider and create two labels in constructor having parent this slider
-
- in slider resizeEvent, move the two labels in respect with new slider width
-
- for the two labels install event filter ON slider object ( or you can subclass labels to implement mouse press/move/release )
-
- in slider event filter I check for mouse press/move/release for the two labels and move them accordingly
-
-
Hello,
I really appreciate your help.
I want to draw an audio sinus wave in a SinusWidget to be positonned on a time line widget.
This SinusWidget will be able to move horizontally from left to right depending on when you want the sinus wave to be played.
I should also have events connected to the SinusWidget to be able to change its width.Because of this, I was thinking about a slider to provide embedded SinusWidget via the handle.
Something like this.
initial example :
ISINUS WIDGETI-----------------------------------------position changed:
-----------------------------ISINUS WIDGETI------------width changed:
----------------ISINUS ________ WIDGETI-----------------What do you think about it?
-
I'm sorry but I don't understand exactly what is your requirement.
In my example I really needed a slider with three values and signals when one of the three value is changed.
From what I understand you only need a "widget" which is moved horizontally from left to right. Is this correct ? If yes, you can use slider directly and either use style sheets or implement a custom style to draw/paint slider "widget" value. -
Cincirin,
Yes I need to move a widget from left to right within a certain range.
I had the idea of a slider because it looks convenient for what I want to achieve ;) (left to right implemented, start and end positions, etc ...)
I am sorry if I explained it in the wrong way.[quote author="cincirin" date="1391516376"]If yes, you can use slider directly and either use style sheets or implement a custom style to draw/paint slider “widget” value.[/quote]
Here is my issue, I don't know how to paint the widget on the slider's handle. I don't think stylesheet can achieve that does it?
And for custom style, how to access the handle.The normal way to go if the slider's handle was a class would be to subclass it and reimplement the paint method.
I am not familiar with QStyle at all, it's probably the reason why I don't know how to do this .... -
"Customizing QSlider":http://qt-project.org/doc/qt-4.8/stylesheet-examples.html#customizing-qslider
See how to customize the slider groove and slider handle
-
[quote author="cincirin" date="1391517392"]"Customizing QSlider":http://qt-project.org/doc/qt-4.8/stylesheet-examples.html#customizing-qslider
See how to customize the slider groove and slider handle[/quote]
:)
Cincirin, I know about this already :)
But this is just to customize the appearance of the handle, not transforming it to a custom widget on which you can add events, etc ...
Or am I mistaken? -
Ok, what events do you need ?
Isn't the default "signals":http://qt-project.org/doc/qt-5/qabstractslider.html#signals what you need ? -
These events are enough yes, but I need them on the slider's handle, not on the slider itself ;)
-
bq. I need them on the slider’s handle
Which one exactly ?
Basically you can subclass slider, obtain a rect of the handle style()->subControlRect and from here you can filter all mouse events from handle only. For paint of course you can reimplement paintEvent, but with style sheet is easily. What other events do you need ? -
I need these ones on the handle:
virtual void mouseDoubleClickEvent(QMouseEvent * event)
virtual void mouseMoveEvent(QMouseEvent * event)
virtual void mousePressEvent(QMouseEvent * event)
virtual void mouseReleaseEvent(QMouseEvent * event)
virtual void moveEvent(QMoveEvent * event)If I understand you, you want to "render" the CustomWidget without embedding it to the handle and filter the events on the rectangle zone and not on the customwidget?
-
ok :)
And for painting the customwidget, you just instantiate it into the paint method of the subclasses slider and parent it to the subclassed slider?
-
And how to you render the customWidget with stylesheet?
-
Yes it was as I thought. So how do I do ? :D
