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Not everyone can perform complex and multi-touch gestures.
Let users operate touchscreens touch screens with one finger and reduced gestures.
Provide single-point operation for all functions.
Please see more detailed information on how to comply with this guideline.
Pointer Cancellation
Make it easier for users to prevent accidental or erroneous pointer input.
People with various disabilities can inadvertently initiate touch or mouse events with unwanted results.
Make pointer cancellation predictable and consistent.
Reduce accidental activation of controls by mouse or touch.
Make it easier for anyone to recover from something they didn’t mean to do.
General Requirements
For functionality that can be operated using a single pointer, at least one of the following should apply:
No Down-Event
The down-event of the pointer is not used to execute any part of the function;
Abort or Undo
Completion of the function is on the up-event, and a mechanism is available to abort the function before completion or to undo the function after completion;
Up Reversal
The up-event reverses any outcome of the preceding down-event;
Essential
Completing the function on the down-event is essential.
Please see more detailed information on how to comply with this guideline.
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