Two FAB with collapsing toolbar

Question

I am trying to create an activity with 2 FAB on its CollapsingToolbarLayout.

I created a regular scrolling activity (which creates with 1 FAB that works great and hide when toolbar is getting collapsed).

Now, I tried to add another FAB, but i can't put it beside the first FAB (can put it only in start/center/end of AppBarLayout.

Also, I tried to put the 2 FAB inside LinearLayout. It looks good, but the FAB are not hiding when the toolbar is getting collapsed.

Here is my xml code:

<?xml version="1.0" encoding="utf-8"?>
<layout 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">

    <data class="MomentActivityBinder">
        <variable
            name="momentViewModel"
            type="com.infibond.infi.timeline.mvp.moment.MomentViewModel"/>
    </data>

    <android.support.design.widget.CoordinatorLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:fitsSystemWindows="true"
        tools:context="com.infibond.infi.timeline.mvp.moment.TimelineMomentActivity">

        <android.support.design.widget.AppBarLayout
            android:id="@+id/app_bar"
            android:layout_width="match_parent"
            android:layout_height="@dimen/app_bar_height"
            android:fitsSystemWindows="true"
            android:theme="@style/AppTheme.AppBarOverlay">

            <android.support.design.widget.CollapsingToolbarLayout
                android:id="@+id/toolbar_layout"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:fitsSystemWindows="true"
                app:contentScrim="?attr/colorPrimary"
                app:layout_scrollFlags="scroll|exitUntilCollapsed">

                <android.support.v7.widget.Toolbar
                    android:id="@+id/toolbar"
                    android:layout_width="match_parent"
                    android:layout_height="?attr/actionBarSize"
                    app:layout_collapseMode="pin"
                    app:popupTheme="@style/AppTheme.PopupOverlay"/>

            </android.support.design.widget.CollapsingToolbarLayout>

        </android.support.design.widget.AppBarLayout>

        <include
            android:id="@+id/moment_content"
            layout="@layout/timeline_content_moment"
            app:momentViewModel="@{momentViewModel}"/>

        <!--two FABs without linear layout -->    

        <LinearLayout
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            app:layout_anchor="@id/app_bar"
            app:layout_anchorGravity="bottom|end"
            android:orientation="horizontal">

            <android.support.design.widget.FloatingActionButton
                android:id="@+id/fab_infi"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_margin="@dimen/margin_baseX1"
                android:src="@drawable/ic_radio_button_checked_black_24px"
                android:tint="@color/gray"
                app:layout_anchor="@id/app_bar"
                app:layout_anchorGravity="bottom|end"
                app:backgroundTint="@color/white"/>

            <android.support.design.widget.FloatingActionButton
                android:id="@+id/fab_share"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_margin="@dimen/margin_baseX1"
                android:src="@drawable/ic_share_mobile_black_24px"
                android:tint="@color/gray"
                app:layout_anchor="@id/app_bar"
                app:layout_anchorGravity="bottom|end"
                app:backgroundTint="@color/white"/>

        </LinearLayout>

    <!--one FAB without linear layout -->

    <!--<android.support.design.widget.FloatingActionButton-->
        <!--android:id="@+id/fab_share"-->
        <!--android:layout_width="wrap_content"-->
        <!--android:layout_height="wrap_content"-->
        <!--android:layout_margin="@dimen/margin_baseX1"-->
        <!--android:src="@drawable/ic_share_mobile_black_24px"-->
        <!--android:tint="@color/gray"-->
        <!--app:layout_anchor="@id/app_bar"-->
        <!--app:layout_anchorGravity="bottom|end"-->
        <!--app:backgroundTint="@color/white"/>

    </android.support.design.widget.CoordinatorLayout>

</layout>

Answer 1

You can use AppbarlayoutChangeListener and on different states manually hide and show the FAB

mAppBarLayout.addOnOffsetChangedListener(new AppBarStateChangeListener() {
         @Override
         public void onStateChanged(AppBarLayout appBarLayout, State state) {
             switch (state) {
                 case COLLAPSED:
                     fab1.hide();
                     fab2.hide();
                     break;
                 case EXPANDED:
                     fab1.show();
                     fab2.show();
                     break;
                 case IDLE:
                     fab1.show();
                     fab2.show();
                     break;
             }
        }
     });

AppBarStateChangeListener.java

public abstract class AppBarStateChangeListener implements AppBarLayout.OnOffsetChangedListener {

public enum State {
    EXPANDED,
    COLLAPSED,
    IDLE
}

private State mCurrentState = State.IDLE;

@Override
public final void onOffsetChanged(AppBarLayout appBarLayout, int i) {
    if (i == 0) {
        if (mCurrentState != State.EXPANDED) {
            onStateChanged(appBarLayout, State.EXPANDED);
        }
        mCurrentState = State.EXPANDED;
    } else if (Math.abs(i) >= appBarLayout.getTotalScrollRange()) {
        if (mCurrentState != State.COLLAPSED) {
            onStateChanged(appBarLayout, State.COLLAPSED);
        }
        mCurrentState = State.COLLAPSED;
    } else {
        if (mCurrentState != State.IDLE) {
            onStateChanged(appBarLayout, State.IDLE);
        }
        mCurrentState = State.IDLE;
    }
}

public abstract void onStateChanged(AppBarLayout appBarLayout, State state);


}