[TextInputLayout] Focused underline stroke can't be hidden in filled mode

[apoi]

Description:

TextInputLayout focused underline stroke can't be hidden in filled mode (app:boxBackgroundMode="filled").

Our application design requires a filled mode TextInputLayout that has a stroke in unfocused state, and does not have a stroke in focused state. This was possible to achieve in Material Components version 1.3, but not in later versions (tested with 1.6 and 1.7).

Expected behavior:

Both of these approaches should hide the underline stroke in focused state:

1. boxStrokeWidthFocused is set to 0dp (this solution used to work in version 1.3)

2. boxStrokeColor color state list entry for state_focused is set to transparent

Source code:

1. boxSrokeWidthFocused is ignored in filled mode, as separate drawables are now used instead: https://github.com/material-components/material-components-android/blob/release-1.7/lib/java/com/google/android/material/textfield/TextInputLayout.java#L4087

2. Default underline drawable is always drawn, and focused underline is drawn on top. Meaning that transparent boxStrokeColor shows the underlaying defaultStrokeColor instead: https://github.com/material-components/material-components-android/blob/release-1.7/lib/java/com/google/android/material/textfield/TextInputLayout.java#L2817

Minimal sample app repro: Please let me know if a sample would be useful.

Android API version: Any API version

Material Library version: 1.6, 1.7

Device: Any device

[leticiarossi]

Hello, I see that setting boxStrokeWidthFocused to 0dp still works but you also have to set boxStrokeWidth to 0dp so it works for both states. Alternatively, for the color, while setting the boxStrokeColor to transparent doesn't work you can set android:alpha to 0 (for all supported states in a CSL for example) and it should also do the trick

[apoi]

Hi @leticiarossi, both of these approaches will also hide the stroke in unfocused state. As I mentioned, our design requires a visible stroke in unfocused state, and no stroke in focused state. This seems to not be possible any more, while it was supported at least in version 1.3.

[leticiarossi]

Oh I see, I misread it at first! Will reopen this then. The only other workaround I can think of would be to add a focus listener and change the stroke then, but that's not ideal. @afohrman do you have any insights?

[drchen]

When the width of the focused underline is 0dp, the bounds of the corresponding drawable is supposed to have 0dp in height. We probably want to check why the underline is still being drawn under that situation?

[apoi]

@drchen This is because the focused underline width is only applied in outline mode, not in filled mode. The relevant code is the link 1 in the description of this issue, https://github.com/material-components/material-components-android/blob/release-1.7/lib/java/com/google/android/material/textfield/TextInputLayout.java#L4087

This logic leading to the wrong behaviour is described in the comment just above:

filled stroke is handled as separate drawables for default and focused states, with constant stroke widths