[TextInputLayout] Allow hint to float always

Is your feature request related to a problem? Please describe. Currently it is impossible to set a hint to both TextInputLayout and TextInputEditText without both overlapping, in some cases it would be nice to show both hints to the user.

Describe the solution you’d like Create an attribute such as:

android:hintAlwaysFloat="true"

Or something like it.

Describe alternatives you’ve considered The easiest alternative to achieve such design is to set a TextView and an EditText within a container and handle both of them.

I’ve also seen the use of reflection to achieve such behaviour, however this brings undesired problems.

Additional context Actual:

<com.google.android.material.textfield.TextInputLayout
            android:id="@+id/input"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="Name">

            <com.google.android.material.textfield.TextInputEditText
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:hint="e. g. Mauro N."
                android:inputType="text"/>

</com.google.android.material.textfield.TextInputLayout>

Suggested:

<com.google.android.material.textfield.TextInputLayout
            android:id="@+id/input"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="Name"
            android:hintAlwaysFloat="true">

            <com.google.android.material.textfield.TextInputEditText
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:hint="e. g. Mauro N."
                android:inputType="text"/>

</com.google.android.material.textfield.TextInputLayout>

[dsn5ft]

We added support for this in https://github.com/material-components/material-components-android/commit/22973ff10305397bfc72fed41684175fee8aeefb via the new expandedHintEnabled attribute, available in version 1.3.0-alpha03.

[zx2c4]

Afaict, placeholderText only shows both when selected, which is bot what you want. https://github.com/material-components/material-components-android/pull/1163 contains a proper (and trivial) fix to make hints always work as desired.