We are having performance problems with Drag and Drop in our application. We've tracked down the root cause and it is because drag and drop indicators are being displayed outside of the parent window Canvas. That causes multiple resizes of the parent Canvas while the drag and drop is in progress.
The root cause of the problem can be seen in the SmartClient demo application, http://www.smartclient.com/docs/9.0/a/system/reference/SmartClient_Explorer.html#dragMove as follows:
1) Open the above example.
2) Size the window so that only it isn't big enough to show both the vertical pawns and horizontal cubes.
3) Scroll the window so that only half of the vertical pawns are showing.
4) Drag one of the cubes over to the pawns.
Result: The horizontal drop line will go outside of the Drag move canvas into the tree control. That will cause a scroll of the Drag move canvas.
Expected Result: The horizontal drop line should be clipped by the edge of the Drag move canvas.
In this particular example, the drop line going outside of the canvas just causes the scroll, which is relatively benign. However, in our application which has tiled windows it causes continuous resize/redraws making drag and drop unusable.
The drag line has similar behavior. If you repeat steps 1, 2, and 3 above and then try to drag one of the Pawns you will see the drag line go outside of the Drag move canvas and a scroll.
SmartClient Version: 9.0/SDK Development Only (expires ) Licensed to: Isomorphic Software (#ISCDocs)
Chrome Version 33.0.1750.117 on a Mac. I've seen the problem with Firefox and Safari on a Mac as well.
The root cause of the problem can be seen in the SmartClient demo application, http://www.smartclient.com/docs/9.0/a/system/reference/SmartClient_Explorer.html#dragMove as follows:
1) Open the above example.
2) Size the window so that only it isn't big enough to show both the vertical pawns and horizontal cubes.
3) Scroll the window so that only half of the vertical pawns are showing.
4) Drag one of the cubes over to the pawns.
Result: The horizontal drop line will go outside of the Drag move canvas into the tree control. That will cause a scroll of the Drag move canvas.
Expected Result: The horizontal drop line should be clipped by the edge of the Drag move canvas.
In this particular example, the drop line going outside of the canvas just causes the scroll, which is relatively benign. However, in our application which has tiled windows it causes continuous resize/redraws making drag and drop unusable.
The drag line has similar behavior. If you repeat steps 1, 2, and 3 above and then try to drag one of the Pawns you will see the drag line go outside of the Drag move canvas and a scroll.
SmartClient Version: 9.0/SDK Development Only (expires ) Licensed to: Isomorphic Software (#ISCDocs)
Chrome Version 33.0.1750.117 on a Mac. I've seen the problem with Firefox and Safari on a Mac as well.