To achieve that I suggest you to create a custom button which will call the saveChanges method
of the Grid and hook up to the saveChanghes event
to check if the form is filled with valid data. For example:
//the form is not valid
//stop the Grid data synchronization
//the form is valid
//submit the form data via Ajax request
//the grid will sync its data automatically
If the Grid validation fails the saveChanges event will not trigger at all. The user will see Grid's validation warning messages.
If the Grid validation passes but form is not valid, the Grid's synchronization will be prevented. The user will see form validation warning messages.
I hope this approach will fit in your scenario.
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