Improvements to the Parent Category Selection `spinner`

[AjeshRPai]

The issue to track the improvements in Parent category selection spinner in the Add Category Screen.

[osullivanchris]

As discussed 1:1 we'd like to update the input field and spacing to look a bit more like below. I'm not sure if by default the label can be at the top of the field like this, or if its only there when the field is active. But let's revisit when this task is being addressed.

Current build left ||| Proposed design right

[neeldoshii]

Can I work on this @AjeshRPai

[AjeshRPai]

Sure @neeldoshii . Thanks for your interest in contributing to this issue.

Tagging @zwarm @irfano who might review the PR .

[irfano]

Thanks @neeldoshii! Please mention in your PRs when they're ready to review.

[neeldoshii]

The spinner doesn't works nested inside <com.google.android.material.textfield.TextInputLayout. So I believe we will need to use AutoCompleteTextView to handle this. What do you think @irfano ?

If AutoCompleteTextView is the answer then my next proposed plan is

1. Migrated AddCategoryFragment to kt
2. Migrating ParentCategorySpinnerAdapter &CategoryNode to kt to understand how the underlying code's working in order to make further changes for AutoCompleteTextView.

[irfano]

Thanks, @neeldoshii! This sounds like a good plan.

We are already using your suggested way in the "Invite People" screen, TextInputLayout with ExposedDropdownMenu style. You can use the same.