wasm: drop shadow steals keyboard input

From email:

Dongmei Wang

I was trying to add a drop shadow effect on a rectangular box using layer.effect. There is a TextEdit item inside the rectangular box. I could see the drop shadow effect around the box; however, there was no response when clicking on the TextEdit item. It appears that this issue is related to item layers. Is item layers supported in Qt for WebAssembly?
>>
>> The code is like:
>> Rectangle {
>> id: background
>> anchors.top: parent.top
>> anchors.topMargin: 50
>> anchors.horizontalCenter: parent.horizontalCenter
>> border.width: 1
>> border.color: "black"
>> width: 120
>> height: 30
>> layer.enabled: true
>> layer.effect: DropShadow

{ >> horizontalOffset: 0 >> verticalOffset: 3 >> radius: 12 >> color: "#80000000" >> samples: 2 * radius + 1 >> spread: 0 >> transparentBorder: true >> }

>> TextEdit

{ >> id: text >> anchors.fill: parent >> text: "enter text..." >> }

>> }

 

Morten:

> Yes, looks like this does not work properly.
>
> The sample code ends up creating a second (offscreen) QWindow for the layer, which I think steals the keyboard input.
>
> We could try to improve handling of QOffscreenSurface QWindows in the wasm platform plugin, or perhaps implement QPlatformIntegration::createPlatformOffscreenSurface() to avoid creating the extra QWindow.
>