How to add a badge above a button?

In my MainActivity class, I have this button:

<Button
    android:id="@+id/target"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@id/speak"
    android:layout_marginTop="20dp"
    android:background="@drawable/button_red"
    android:text="@string/target" />

I now want to add a badge with the number 1, using Material Design (see the documentation).

This is how I tried:

public void setBadge() {
    BadgeDrawable badgeDrawable =  BadgeDrawable.create(MainActivity.this);
    badgeDrawable.setNumber(1);
    BadgeUtils.attachBadgeDrawable(badgeDrawable, findViewById(R.id.target));
}

but what I get is the error

‘attachBadgeDrawable(com.google.android.material.badge.BadgeDrawable, android.view.View, android.widget.FrameLayout)’ in ‘com.google.android.material.badge.BadgeUtils’ cannot be applied to ‘(com.google.android.material.badge.BadgeDrawable, android.view.View)’

Answer

If you tried this on a device with <18 API this might work;

In your XML wrap the button with a FrameLayout;

<FrameLayout
    android:id="@+id/frame"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">
    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:text="HELLO"/>
</FrameLayout>

In your Activity;

//I've used post to eliminate race condition between the button and its badge.
button.post(() -> {
    BadgeDrawable badgeDrawable =  BadgeDrawable.create(MainActivity.this);
    badgeDrawable.setNumber(1);
    //Note that there is a third argument which is our FrameLayout
    BadgeUtils.attachBadgeDrawable(badgeDrawable, findViewById(R.id.button), findViewById(R.id.frame));
});