A widged surrounded by another used as a Mask

[gab74]

Good morning,
i've to develop a map software.
The map is in a qwidget and all is ok.
I've to surround the map with a circle angle degree used as mask in which I've to insert some other widget.
So i need to know how can i insert a circle png over a widget, but i must click the above layer.

See the picture:
I've the png picture as the blue mask with transparent hole, the big angle degree cicrle
I can click the underground map.

Anyone can help me in showing an example how can i develop a widget sourrounded by another ?
See the picture attached
I must use qt 4.2

[anda_skoa]

Sounds to me more like a use case for a single widget.

First it draws the inner part, then the "hole" image on top.
Or even just using a QPainterPath to draw the hole.

Cheers,
_

[gab74]

So :
i have the widget thats draws the map, this widget is connected to a map server that generate the map.
If i click on map i can zoom pan ecc ecc like any map programs...
I do not understand how can i draw the hole and the blue borders over this widget.
Con you be more specific ?
Consider that in the blue part i've to insert check boxes and button to manage the map...
Please can you write me a little pseudo-code ?

[anda_skoa]

I would draw the blue part in the same widget as the map, i.e. in that widget's paintEvent() method.

Buttons and other widgets can then easily be placed on top, i.e. as children of the map widget.

Cheers,
_

[gab74]

Ok Thank you very much.
Last question.
As you can see there are numbers and lines in the circle to represent Degree.
How can i solve this last problem ?
I think using a trasparent png is a wrong approach..

[anda_skoa]

Also doable in paintEvent(), QPainter has methods for drawing text, lines, etc.

Cheers,
_

[gab74]

Sorry i cannot yed solved my problem.
I have a QMainWindow with a QFrame
in QFrame i have a proprietary qtWidget that draws the map.
i added this proprietary widget to Qframe with

mapFrame->layout()->addwidget(MyProprietaryWidget)

mapFrame->layout()->addwidget(MyProprietaryWidget)

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And all works well i see the map inside the QFrame.
Now i need to add the circle mask.. to mask some map area as the image attached in thread.
I think i've to sublcass paintevent of QFrame and not of MainWindow to draw the shapes :
So
1) How can i override only QFrame method to add a shape over ?
Can you explain me with meta code ??? or a simple example ?
I think after adding the proprietary widget i can draw shapes to mask some map area.
Thank you

[anda_skoa]

My suggestion would be to

1) derive from that map widget,
2) overwrite paintEvent()
2a) call the base class paintEvent to draw the map
2b) draw the mask on top

I think your other options is to
1) derive a new class from QWidget
2) implement paintEvent() to draw the mask
3) add a layout to the map widget, with spacing set to 0
4) add an instance of your widget to the layout

Cheers,
_