SystemError with dpg.file_dialog about dearpygui HOT 2 OPEN

The file dialog behaves much like a regular dpg.window (it's a window, after all). In particular, when you click OK or Cancel, it doesn't get deleted - instead, it gets hidden. This way you can query some properties from it or reuse the dialog widget later.

You can see it by adding the following line to your example:

dpg.show_item_registry()

Look at the File Dialogs section in the Item Registry.

You can even bring it back by clicking the Show button in the Item Registry.

So when you click the Load button in your examlpe second time, there's already a file dialog in the GUI with the tag "file_selector". DPG actually tells you that straight, before the first SystemError message:

Exception:
Error:     [1000]
Command:   add alias
Item:      0
Label:     Not found
Item Type: Unknown
Message:   Alias already exists

The same would happen if you were creating a dpg.window that way. When the window is closed, it remains hidden until you delete it explicitly with dpg.delete_item().

It is perfectly normal to use a tag with dpg.file_dialog, as long as your code manages the item lifetime properly:

• Either delete the file dialog after OK/Cancel and re-create each time,
• or create it once (probably before first use) and then use dpg.show("file_selector") instead of creating the file dialog again.

from dearpygui.

Hi Vladimir,

Thanks for the explanation. That logic and message is what made me try removing the tag to see if it fixes the problem. I get that is how it works, but the documentation doesn't mention this and the example there uses a tag without managing the dialog.

In any other GUI library I've used, I don't recall dialog windows having to managed this way. Just my opinion, but this feels like an implementation detail that should be handled in the library itself. It is nice that it would be an option to keep an instance of the dialog and show / hide it manually, but again, maybe something that should be handled automatically by default.

Also, I found in debug mode it crashes the whole program. In normal running mode, it emits the error I posted but the app remains open and an additional file dialog is opened (if the first one wasn't closed).

from dearpygui.