Add Delete action

[evowizz]

This change adds the ability for users to delete notes using a menu action within the toolbar (under "Split screen").

This is done by marking the note as pending for deletion.

isPendingDeletion was already available, I just used it for this action. The icon R.drawable.ic_twotone_delete_24 was also already within the app.

Screenshot (Click for bigger preview):

[saket]

Nice, thanks! I had so far avoided doing this because deleting a note is a dangerous action. If sync is not setup, there's no way to recover deleted notes. Let's give this option only if sync is setup? If you're familiar with reaktive/rxjava, you can inject Syncer to the presenter and use Syncer#status for showing delete only if the status is enabled.

[evowizz]

I was able to add this behavior on my local branch. However, I wanted to make sure the current behavior was understood here.

Removing the Delete Menu action when the Syncer status is not Enabled means that the only way for users to fully delete a note is by removing the entire content of that note (making the note empty). And if the Menu action is enabled, clicking it will remove the note from both the user's repository and the local database.

I'm not sure I understand why it would be better only if the Syncer status is Enabled because in both cases there's no way to recover deleted notes?

[manueldidonna]

Nice, thanks! I had so far avoided doing this because deleting a note is a dangerous action. If sync is not setup, there's no way to recover deleted notes.

We could think of adding a bin to show the deleted notes. The bin would be automatically emptied at regular time intervals by a Worker. The bin would be a sort of 'special folder', graphically distinguished from the normal ones and without the permission to manually add new notes there.

[saket]

I'm not sure I understand why it would be better only if the Syncer status is Enabled because in both cases there's no way to recover deleted notes?

If sync is enabled then deleted notes will be part of user's version history. Recovering deleted notes is one git revert command away.

We could think of adding a bin to show the deleted notes

Right that's the eventual plan for the future, and also a reason why I hadn't added a delete action yet. But now I think it's okay to let users delete notes provided that they've sync enabled.

I also want to add a confirmation popup for deleting notes, similar to how Press shows a confirmation popup menu if you try disabling sync. But that's going to require some changes to how EditorPresenter handles menu events so I can do it later.

[saket]

This looks good enough. I'd remove an extra distinctUntilChanged(), but I can do that myself. Thanks for contributing!

[evowizz]

Awesome, thanks!