[TabLayout] Indicator with tabIndicatorFullWidth=false does not match label if label is not centered

Description:

I have this style

<style name="TabLayoutStyle" parent="Widget.MaterialComponents.TabLayout">
		<item name="tabIndicatorFullWidth">false</item>
		<item name="tabMode">scrollable</item>
		<item name="tabPaddingStart">0dp</item>
		<item name="tabPaddingEnd">16dp</item>
		<item name="tabGravity">start</item>
		<item name="tabContentStart">0dp</item>
		<item name="tabMinWidth">0dp</item>

	</style>

and it renders as this

Expected behavior:

Indicator should match label width

Android API version: 29

Material Library version: 1,3.0-alpha01

[denis-bezrukov]

Is there a workaround for this? Or will you accept a PR with a fix?

after a quick look, it seems that tabViewCenterX should take paddings into account

tabViewCenterX = (tabView.getLeft() + tabPaddingStart + tabView.getRight() - tabPaddingEnd) / 2;

// instead of 

tabViewCenterX = (tabView.getLeft() + tabView.getRight()) / 2;

in https://github.com/material-components/material-components-android/blob/0afcb48f14a7af3db3712be44d7984c8d89e25fb/lib/java/com/google/android/material/tabs/TabIndicatorInterpolator.java#L80

UPD as a workaround you can use equal start/end paddings and just translate the whole TabLayout by difference between original padding and new one. e.g.

<item name="tabPaddingStart">0dp</item>
<item name="tabPaddingEnd">16dp</item>

can be achieved as

<item name="tabPaddingStart">8dp</item>
<item name="tabPaddingEnd">8dp</item>
<item name="translationX">-8dp</item> // it's old tabPaddingStart - new tabPaddingStart (0dp - 8dp)

[AramKocharyan]

Is this fixed?