Add support for moving cursor on spacebar slide. Fixes #91

[storvik]

I tried to tackle issue #91.

This pull request adds two settings:

• Spacebar slide: Enable / Disable spacebar sliding
• Slide sensitivity: Sensitivity when sliding

Also KeyItemC was extended with slideType. Slide type defaults to NONE, which is the old behavior. MOVE_CURSOR slide type is for keys meant to be used with the new "slide to move cursor"-functionality. The thought was to also extend this with another type. DELETE, which marks characters backwards on slide and deletes them on release (like florissboard and Gboard). If slideType is MOVE_CURSOR and the setting is turned off, spacebar will behave like it does now. In other words, this should not break default behavior.

See gif for a simple demo

Not sure if these modifications are OK to you, but it seems to be working fine on my end now. I'm no Android developer, so any feedback is much welcome!

[storvik]

After using this for a day I noticed that scrolling past text could move focus out of text field. Seems like DPAD is used for navigation between UI elements too, that's probably why this happens.

Latest additions in 571fdc7 checks if length of text before / after cursor is 0. If there is no more text it aborts the movement and resets sliding offset.

So far this is working great, and I have tested it in every application where the focus issue was present. That is Messenger, Teams and Snapchat.

[sslater11]

Oh wow, this looks awesome! I've wanted this feature for a while and was wondering how to implement it.
Thank you 😁!

[storvik]

Thanks @sslater11! Please take it for a test-drive if you get a chance. So far it's working great for me.

[dessalines]

Wow, this is gonna be a great addition, thx for this!

The main thing that I commented on below, is that sliding might also be useful in the future for the delete key, so I'd rename it from spacebar_side to something more generic.

[storvik]

@dessalines thanks for the feedback!

I agree that slide_enabled is better, so that fixed. Also migrations are now combined, wasn't aware that I could do that.

[storvik]

I haven't noticed that the spacebar wasn't being released until you mentioned it. Fixed it by calling the doneKeyAction function after slide. Seems to be working correctly now.

When this is merged I will try to look into "slide to delete". Didn't find an obvious way to implement that yet, and as I'm very new to android development things have a tendency to take some time.

[dessalines]

Tested and it works great, thx!