drag'n drop: why does the parent also become a droptarget

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marcussilfver@gmail.com - 23 Oct 2007 11:56 GMT

I am completely new to implementing drag and drop.

I have made a class called DropPanel that extends JPanel. DropPanel
implements the DropTargetListener interface. I place a DropPanel as a
component of a JPanel and executes my application...

The wierd thing is that my dropPanel.drop method is called even if I
drop the draggable outside my DropPanel (on the JPanel that contains
the DropPanel).

This behaviour forces me to do a check in my drop method for the
dropPanel's bounds and compare this with the mouse position and reject
the drop if it is outside dropPanel.

Is it supposed to be like this?

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Andrew Thompson - 23 Oct 2007 12:37 GMT

>I am completely new to implementing drag and drop.

...

>This behaviour forces me to do a check in my drop method for the
>dropPanel's bounds and compare this with the mouse position and reject
>the drop if it is outside dropPanel.
>
>Is it supposed to be like this?

From my vague recollection of implementing D'n'D in
an animated Gif project, that is wrong. Originally I
had added the drop listener to an 'image list' on the
left of the GUI - but decided it made sense to allow
images to be dropped anywhere in the GUI. AFAIR
I had to move the drop listener to the frame to allow
the user to 'drop anywhere'.

Have you got an SSCCE that shows this behaviour?

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Andrew Thompson
http://www.athompson.info/andrew/

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marcussilfver@gmail.com - 24 Oct 2007 06:51 GMT

> marcussilf...@gmail.com wrote:
> >I am completely new to implementing drag and drop.
[quoted text clipped - 14 lines]
>
> Have you got an SSCCE that shows this behaviour?

Thanks for answering. What is a SSCCE?

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Andrew Thompson - 24 Oct 2007 08:56 GMT

>> marcussilf...@gmail.com wrote:
>> >...drag and drop.

...

>> Have you got an SSCCE that shows this behaviour?
>
>Thanks for answering. ..

You're welcome.

>..What is a SSCCE?

Huh. I thought you were a regular on the group when
I failed to include the link, but noticing you are a GG
poster, I'll try to lead you to it via other means.

Try this search..
http://groups.google.com/group/search?group=comp.lang.java.gui&q=sscce>

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Andrew Thompson
http://www.athompson.info/andrew/

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marcussilfver@gmail.com - 26 Oct 2007 08:15 GMT

> marcussilf...@gmail.com wrote:
> >> marcussilf...@gmail.com wrote:
[quoted text clipped - 18 lines]
>
> Message posted viahttp://www.javakb.com

I found the problem. I sent in the droptarget for both arguments to
setDropTarget. Like setDropTarget (new DropTarget(dropPanel,
dropPanel).

Thanks for your time with this.

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drag'n drop: why does the parent also become a droptarget

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