Haptic feedback / wait message when pressing buttons

[jo-spek]

Problem: Field work in Kenya showed that many people had rather old and slow Android smartphones that usually wouldn't react instantly when clicking a button. That became quite a problem when adding points, because people would push the "Add point" button again and again until finally a registered point was displayed on the map. By then however, they would have pushed so often that multiple points appeared, sometimes in far away locations.

Possible solutions:

• Haptic feedback: Short vibration when pressing a button, especially the 'Add point' button.
• Instant visual feedback: "Please wait" message or some loading icon displaying as the very first thing when pressing a button before the point registration classes are even called.
  Both together would be great, too.

[gino-m]

@jo-spek Great suggestion, queuing this as P1 for GA.

[kenstershiro]

@jabramowitz5 would also find this useful based on experience in the field. Use case of dropping a pin in the field should be included.

[gino-m]

I suspect that the issue here isn't so much about the devices, but rather that they're no visual or other feedback when "Add point" is clicked. https://github.com/google/ground-android/issues/2908 should also help here.

[kenstershiro]

Agreed this should be looked at together with #2908 and #2607

[gino-m]

Adding the point is instantaneous, so there shouldn't be the need for a wait message. Rescoping to just "haptic feedback" for clarity.

#2607 will change the cursor to indicate something was added, and #2908 will prevent duplicate vertices from being added.