fix: Simplify & improve DataGridColumn support in LostFocus + fix related initial cell selection bug #4511
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Fixes #4374
Users reported that DataGrid wouldn't work well with some types of DataGridColumns after #4206. I was able to reproduce the broken behavior with DataGridComboBoxColumn. Additionally, DataGridCheckBoxColumn was reported as flickering as it required an unnatural number of invocations to simply edit the Checked state. With this PR, I do the following:
PR Type
What kind of change does this PR introduce?
Bugfix; Sample app changes; minor Refactoring
What is the current behavior?
Clicking on a bound DataGridCheckBoxColumn in DataGrid will require an additional invocation before entering "edit mode". This bug produced an undesirable flickering effect for DataGridCheckBoxColumn.
What is the new behavior?
Only a single invocation (click, tap) is now required to enter edit mode. Additional invocations will be observed by the editing element itself rather than being ignored (that is, until the editing element loses focus)
PR Checklist
Please check if your PR fulfills the following requirements:
Other information
N/A