# dialog_reopen_example

![](dialog_reopen_example.jpg)

## Short description

This examples demonstrates, how a dialog can be closed from its own handler, just to be opened again.

```{warning}
There are very rare occasions, where you should need this. Use this approach only, if you know what you are doing.
```

## Highlights

The approach consists of two steps. First, declare a guard variable that yields `True` if the dialog should be reopened.

```python
[...]
reopen = True
while reopen:
  gom.script.sys.show_user_defined_dialog (dialog=DIALOG)
```

The example dialog contains a button to close/reopen the dialog (see top image). One of the few use cases could be, that you need to adapt the `filter` property of an `Selection element` widget after some dialog interaction, which can only be done when the dialog is closed.

To achieve this, the dialog event handler is used:

```python
def dialog_event_handler (widget):
  global reopen
  if str(widget) == "initialize":
    reopen = False
  if widget == DIALOG.button:
    gom.script.sys.close_user_defined_dialog (dialog=DIALOG)
    gom.script.sys.delay_script (time=1) # Do stuff while dialog is closed
    reopen = True
```

```{warning}
Never reopen the dialog directly from its own handler to prevent getting undefined behaviour.
```


## Related

* How-to: [Using Script Dialogs](../../howtos/python_api_introduction/script_dialogs_introduction.md)