[MaterialButton] Icon size of icon buttons doesn't match M3 specs

[patzly]

Description: Hi, it seems that the icon-only button (base) style Widget.Material3.Button.IconButton is using a wrong icon size. The attribute iconSize uses the resource @dimen/m3_btn_icon_only_default_size with a value of 20dp instead of 24dp as it is described in the specs.

Expected behavior: The dimension @dimen/m3_btn_icon_only_default_size would need to be set to 24dp instead of 20dp.

Source code:

<dimen name="m3_btn_icon_only_default_size">20dp</dimen>

Material Library version: 1.8.0-alpha02

[drchen]

Raaj, can you take a look and confirm if we should fix it?

[raajkumars]

Yes, this must be fixed.

[patzly]

I have to add that iconSize is not the only attribute with a wrong value, if only this dimen would be set to 24dp the final icon button size would be too big with 52dp because of the padding/inset attributes. The following combination leads to the expected button size for me:

Dimen ID	Current value	New value
m3_btn_icon_only_default_size	20dp	24dp
m3_btn_icon_only_default_padding	10dp	6dp
m3_btn_inset	4dp	6dp

As you can see the dimen m3_btn_inset would have to be changed but isn't icon-only specific, so probably a new dimen for icon-only buttons is required. Thank you!

[raajkumars]

@patzly Thanks for the detailed reply. Much appreciated