Re: [Jsynthlib-devel] incompatible Scene class

[Hiroo H. <hir...@co...>]

Hi,

Last night I checked in the various change for drag&drop (cut&paster,
TransferHandler/Transferable) related code.

The most important update is that now we can drag&drop Scene and can
drag&drop Patch and Scene between a LibraryFrame and a SceneFrame.  This
has been a known bug for a long time.

Hiroo> Jeff> I'm getting the following exception when I try to drag
Hiroo> Jeff> a patch from a bank window to a library window. Can
Hiroo> Jeff> anyone reproduce this?
Hiroo> 
Hiroo> Hiroo> Yes, I can.  I guess my bug fix made this bug.  I'll take a look.

I also made a fix for this, but I don't understand why the fix is
necessary.  For example if I drag&drop a Patch from a LibraryFrame to
another LibraryFrame, you will see the following debug message if you
run JSynthLib with debug option ('2').

DBG>PatchListTransferHandler.createTransferable [Roland TD6 Drumkit] f0 41 00 00 3f 12 41 62 00 00 41 63 75 53 74 69 .. 02 74 f7
DBG>Patch.isDataFlavorSupported java.awt.datatransfer.DataFlavor[mimetype=application/x-java-serialized-object;representationclass=[Lcore.IPatch;]
DBG>Patch.getTransferData: flavor=java.awt.datatransfer.DataFlavor[mimetype=application/x-java-serialized-object;representationclass=[Lcore.IPatch;]
DBG>Patch.getTransferData: Patch=[Roland TD6 Drumkit] f0 41 00 00 3f 12 41 62 00 00 41 63 75 53 74 69 .. 02 74 f7, MIDI-OX
DBG>PatchTransferHandler.importData: t=java.awt.dnd.DropTargetContext$TransferableProxy@57828d
DBG>PatchTransferHandler.importData: Patch=[null] f0 41 00 00 3f 12 41 62 00 00 41 63 75 53 74 69 .. 02 74 f7MIDI-OX

This means that the Patch.driver field was set properly when
Patch.getTransferData returns a patch.

But when PatchTransferHandler.importData receives the data, the value of driver
field becomes 'null'.  Patch.driver field is private access now, and
is set only by Patch.setDriver(IPatchDriver) method.  When the argument
Patch.setDriver() is null, setDriver method sets driver field Generic
Driver.  This means there is no way to set 'null' on Patch.driver field.

Scene also has similar problem.  driver field for a Patch in a Scene
becomes 'null' when it is received by a importData method.

For now I've fixed this bug by adding the following code.
        p.setDriver((IPatchDriver) DriverUtil.chooseDriver(p.getByteArray()));

This is very strange.  I don't understand why this line is required.  If
you have any clue, let me know.
-- 
Hiroo Hayashi