[Development] Drag and Drop Issue in Qt-5.3.2 with QML on QNX Platform only.

[Prashant Purohit]

Hi All,

We have created one application where there are multiple icons present
in a GridView.
Each delegate of the grid is a composite control with an icon and text.
(This is similar to phone apps screen on Android/iOS devices).

Similar to apps screen on mobile devices, user can drag and drop icons
across multiple pages of the gridview.
Also, there are navigation buttons on the right and left side of the icons grid,
when an icon is dragged on top of the navigation buttons, the page
scrolls left OR right to display the corresponding grid view.

The issue which we are facing is that while dragging an icon across
multiple pages(most of the times),
the icon being dragged gets stuck and does not get dropped or user
sees a screen freeze for dragged icon but rest of the functionality
like mouse click or page change works fine.

Initially, we could duplicate this issue almost always and found one
solution by increasing the cacheBuffer for GridView.
Current value for cacheBuffer is 100000.

Above fix has reduced the occurrence of this issue but still issue is
reproducing after couple of repeated trials.
Hence, this issue is not completely fixed.

We are using QT 5.3.2 with QML on QNX.

The point to note here is that when we tried same code on Linux
machine with QT-5.3.2, this issue does not occur.

Is there any fix done for QT-QML-QNX related to this issue?

We would really appreciate any inputs on this.

Thanks,
Prashant