<android.support.design.widget.CoordinatorLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
</android.support.design.widget.AppBarLayout>
<android.support.design.widget.FloatingActionButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_behavior=".CustomFloatingActionButtonBehavior"
app:srcCompat="@drawable/ic_add" />
</android.support.design.widget.CoordinatorLayout>
public class CustomFloatingActionButtonBehavior extends FloatingActionButton.Behavior {
@Override
public boolean onStartNestedScroll(@NonNull CoordinatorLayout coordinatorLayout, @NonNull FloatingActionButton child,
@NonNull View directTargetChild, @NonNull View target, int axes, int type) {
return axes == ViewCompat.SCROLL_AXIS_VERTICAL;
}
@Override
public void onNestedScroll(@NonNull CoordinatorLayout coordinatorLayout, @NonNull FloatingActionButton child,
@NonNull View target, int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed, int type) {
if (dyConsumed > 0 && child.getVisibility() == View.VISIBLE) {
child.hide();
} else if (dyConsumed < 0 && child.getVisibility() != View.VISIBLE) {
child.show();
}
}
}
groovy
implementation 'com.android.support:design:28.0.0'
