Added drop support to the NavigationBar

[soumyamahunt]

As requested in #634, you can drop files/folders in navigationbar items to move that file/folder to that path. Demo:

[soumyamahunt]

Currently, after I drop on an item the item is highlighted, I am working on a fix for it. May be related to #1052.

[tsvietOK]

When moving file to the same directory it create a new file with the same name with added '- copy". I think this operation should not be available.

[soumyamahunt]

When moving file to the same directory it create a new file with the same name with added '- copy". I think this operation should not be available.

Fixed that, already existing items are skipped.

[tsvietOK]

I am still able to drop item to last navigation bar path item

[soumyamahunt]

I am still able to drop item to last navigation bar path item

Does dropping create a duplicate file as you stated before??

[tsvietOK]

No, it is doing nothing. But text "Move to" still exists, so it could mislead user.

[soumyamahunt]

No, it is doing nothing. But text "Move to" still exists, so it could mislead user.

That is the default Windows Explorer behavior, when you drag items to any path items it displays the move to text.

May be I should add a dialog to user explaining the move operation cannot complete.

[tsvietOK]

Or just remove this operation from last path item? If it is not possible or too hard, add a dialog.

[soumyamahunt]

Or just remove this operation from last path item?

The reason I am deciding against that is because user might want to drop files to the pathitems from another instance or another app in case if their gridview is blocked by another window. This is the default behavior in Windows Explorer.

If it is not possible or too hard, add a dialog.

I tried to add a dialog but the method failed with RPC_E_WRONG_THREAD exception. Queuing the task in ui thread using dispatcher also failed. Similar behavior implemented for dragging a parent folder to child folder also fails. So I have disabled both methods for now until a solution is found.

Currently, I have implemented to check if item already exist in the folder in DragOver method.

[tsvietOK]

If check of an item already exist in the folder now implemented, user dialog is no longer needed. Please, remove it.

[soumyamahunt]

If check of an item already exist in the folder now implemented, user dialog is no longer needed. Please, remove it.

I have commented out the dialog part, if any workaround for the issue is found, then it can be reenabled.