Drag and drop broken in VM with absolute positioned pointer device

[phw]

I noticed that since a recent release drag and drop inside applications is not working. You cannot initiate a drag from widgets supporting this (e.g. from a tree widget). I experienced this with both Picard and Clementine.

Droping from outside the applications (e.g. from file browser) works.

I can't say exactly when this broke

[threedeyes]

Drop implemented only for now, sorry.
Drag from Qt apps not implemented in QPA plugin.

[phw]

Strange, I was under the impression it worked at some point, at least inside the same application. But probably I never really tried it and I just was under the impression that dragging inside the same Qt application would not require much platform specific code ;)

What would be necessary to implement drag?

[threedeyes]

You right. Drag inside app works. It's base functional.
Drag to outside app not implemented only.

[phw]

Drag inside app works. It's base functional.

Ok, so my bug report is only about drag inside app not working currently.

[threedeyes]

Hm. How i can reproduce it?
I try drag files inside picard and works fine.

[phw]

Sorry for the delay, my Haiku time is a bit limited at the moment.

Regarding the issue it is really strange. Actually everything that involves pressing the mouse button and dragging does not work in Qt5 apps for me. This e.g. also includes text selection with the mouse, this works in no Qt5 app. E.g. also KWrite. It works fine in apps using the Haiku UI, e.g. Koder. I tested with Picard, KWrite, Otter, Clementine.

About Haiku shows I'm on hrev54549, and all packages are up to date. These are the Qt5 packages I have installed (currently version 5.15.0-3):

S       qca                      Qt Cryptographic Architecture                                                       
S       qt5                      A comprehensive C++ application development framework                               
S       qt5_devel                A comprehensive C++ application development framework (development files)           
S       qthaikuplugins           Haiku platform plugins for Qt5                                                      
S       qtwebkit                 WebKit rendering library for the Qt5 framework                                      
S       qtwebkit_devel           WebKit rendering library for the Qt5 framework (development files)

I'm running Haiku inside Virtual box, I wonder if it could be a hardware issue then? But then I would assume also broken behavior for native Haiku UI. The mouse dragging definitely worked a while back also in Qt apps. Could something else interfere?

[phw]

I'm running Haiku inside Virtual box, I wonder if it could be a hardware issue then?

Here we go, it is indeed somehow Virtualbox related: I had configured Virtualbox to provide a USB tablet as pointer device, because this worked better for mouse handling in Haiku in the past. If I do this I see two pointer devices in Haiku's input preferences: "Extended PS/2 Mouse 1" and "USB Tablet 1". This setup breaks the Qt5 drag and drop.

If I change Virtualbox to provide a PS/2 mouse instead, then Haiku only has a single pointer device ""Extended PS/2 Mouse 1". And then Qt5 drag and drop works as expected.

Now the question: Is this a bug either in Qt5 (or even in Haiku) which makes it misbehave if there is more than one pointer device or maybe USB Tablet in general? Or is this something that broke in Virtualbox?

[threedeyes]

I would test it, but unfortunately I don't have VirtualBox. Haiku is my main and only system on my PC.
I have more than one pointer devices (usb mouse and wacom tablet) and drag works fine.

[phw]

@threedeyes More data for this. I am now using QEMU instead of VirtualBox. Drag and drop inside Qt5 app (Picard) works if I use a virtual PS/2 mouse. Unfortunately mouse movement in Haiku with this setting is very erratic, so I'd want to use QEMU's usb-tablet device instead, which is a "Pointer device that uses absolute coordinates (like a touchscreen)". This is what I have set in my QEMU XML config for the machine:

<input type="tablet" bus="usb">
    <address type="usb" bus="0" port="6"/>
</input>

Using this absolute positioned device now breaks Qt drag and drop again (same behavior as on VirtualBox).

[ghost]

I have more than one pointer devices (usb mouse and wacom tablet) and drag works fine.

For me dragging works correctly with my trackball in qt apps but it does not work with my wacom tablet. This is also a native installation.
For example in Quaternion splitters can be resized with the mouse but not with the tablet pen. (I don't know about touch with the tablet, it is not support on Haiku currently)