Android Build an Interactive Story App Finishing the User Interface Customizing a Button

what is wrong with android:textColor="#ffffff"

I am trying to change the text color of the button to white, but not working.

activity_main.xml
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <Button
        android:id="@+id/thrustButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/thrust_label"
        android:background="#ffaa0000"
        android:textColor="#fff"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</android.support.constraint.ConstraintLayout>

1 Answer

joelearner
joelearner
49,609 Points

Hi Robel,

The reason it is not working is because you are using the RGB code for white: #FFFFFF. Alpha RGB or ARGB has an alpha code in the beginning which is used to specify the transparency/opacity.

That's what the hint for the question means: "(Don't forget the "ff" alpha code at the beginning!)".

So add the extra 2 F's and you'll have #FFFFFFFF.

Cheers!