Friday, July 27, 2012

Re: DragOverEvent issue

JSNI to access the "types" property of the DataTransfer object?
(along with using specific types to distinguish different types of data, rather than inferring from the content for a single type)

On Friday, July 27, 2012 5:27:22 PM UTC+2, Thomas Lefort wrote:
OK, thanks for the fast answer Thomas. I guess it's not good news though. Any recommendations on how to distinguish between objects being dragged over a widget using the dragovervent?

On Friday, 27 July 2012 15:52:29 UTC+2, Thomas Lefort wrote:
I have an issue with DragOverEvent.

At drag start I set my event data to a certain value, as follows:

panel.addDomHandler(new DragStartHandler() {
public void onDragStart(DragStartEvent event) {
event.setData("text", ResourceWidget.this.resource.getClass().getName());
event.getDataTransfer().setDragImage(panel.getElement(), 10, 10);
                                                ... some more code
}, DragStartEvent.getType());

On hover and on drop I test the value of the event data as follows:

campaignMap.addDomHandler(new DragOverHandler() {
public void onDragOver(DragOverEvent event) {
   if(event.getData("text") != null) {
                                              (1)  ... some more code
}, DragOverEvent.getType());
campaignMap.addDomHandler(new DropHandler() {
public void onDrop(DropEvent event) {
   if(event.getData("text") != null) {
                                              (2)  ... some more code
}, DropEvent.getType());
The issue is that with the hover event I get always null for my data value whilst for the drop I get the right value, ie (1) is never run and (2) runs.

In the end the drag and drop works, but I would also like to make use of the drag event to display some information based on the value of the data.

Any idea? is this a bug?



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