FloatingActionButton不会启动不可见

Question

我想做一个FAB，在点击后打开剩下的2个其他FAB。但它并没有开始隐形。我在那些代码行中使用了所有方法，但它不起作用。 (ScaleX-Y = 0, android:invisibility, setInvisibility etc..)

DersActivity.java

private Boolean isFabOpen = false;
private FloatingActionButton fab_ders, fab_ders_ara, fab_ders_ekle;
private Animation fab_open, fab_close, rotate_forward, rotate_backward;

@Override
protected void onCreate(Bundle savedInstanceState) {
    ...
    ...
    fab_ders = (FloatingActionButton) findViewById(R.id.fab_ders);
    fab_ders_ara = (FloatingActionButton) findViewById(R.id.fab_ders_ara);
    fab_ders_ekle = (FloatingActionButton) findViewById(R.id.fab_ders_ekle);
    fab_open = AnimationUtils.loadAnimation(getApplicationContext(), R.anim.fab_open_ders);
    fab_close = AnimationUtils.loadAnimation(getApplicationContext(), R.anim.fab_close_ders);
    rotate_forward = AnimationUtils.loadAnimation(getApplicationContext(), R.anim.rotate_forward);
    rotate_backward = AnimationUtils.loadAnimation(getApplicationContext(), R.anim.rotate_backward);
    fab_ders.setOnClickListener(this);
    fab_ders_ara.setOnClickListener(this);
    fab_ders_ekle.setOnClickListener(this);
    ...
    ...
}

@Override
public void onClick(View v) {
    int id = v.getId();
    switch (id) {
        case R.id.fab_ders:

            animateFAB();
            break;
        case R.id.fab_ders_ara:

            Log.d("Test", "Fab 1");
            break;
        case R.id.fab_ders_ekle:

            Log.d("Test", "Fab 2");
            break;
    }
}

public void animateFAB() {

    if (isFabOpen) {

        fab_ders.startAnimation(rotate_backward);
        fab_ders_ara.startAnimation(fab_close);
        fab_ders_ekle.startAnimation(fab_close);
        fab_ders_ara.setClickable(false);
        fab_ders_ekle.setClickable(false);
        isFabOpen = false;
        Log.d("Test", "close");

    } else {

        fab_ders.startAnimation(rotate_forward);
        fab_ders_ara.startAnimation(fab_open);
        fab_ders_ekle.startAnimation(fab_open);
        fab_ders_ara.setClickable(true);
        fab_ders_ekle.setClickable(true);
        isFabOpen = true;
        Log.d("Test", "open");

    }
}

我在此文件中使用Animation但问题并不重要。

activity_ders.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout
    android:id="@+id/drawer_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"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:openDrawer="start">

    <android.support.design.widget.CoordinatorLayout
        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"
        android:fitsSystemWindows="true"
        tools:context=".DersActivity">

        <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:elevation="5dp"
            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"
                android:elevation="5dp"
                app:contentScrim="?attr/colorPrimary"
                app:layout_scrollFlags="scroll|exitUntilCollapsed"
                app:expandedTitleMarginStart="48dp"
                app:expandedTitleMarginEnd="64dp">

                <include layout="@layout/tool_bar2"/>

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

        <include layout="@layout/content_ders"/>

        <android.support.design.widget.FloatingActionButton
            android:id="@+id/fab_ders_ekle"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginRight="@dimen/fab2_margin"
            android:src="@drawable/ic_add_circle_white_24dp"
            android:visibility="gone"
            app:backgroundTint="@color/colorFAB2"
            app:elevation="6dp"
            app:pressedTranslationZ="12dp"
            app:fabSize="mini"
            android:scaleX="0.0"
            android:scaleY="0.0"
            android:alpha="0.0"
            app:layout_anchor="@id/app_bar"
            app:layout_anchorGravity="bottom|end"/>

        <android.support.design.widget.FloatingActionButton
            android:id="@+id/fab_ders_ara"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginRight="@dimen/fab1_margin"
            android:src="@drawable/ic_search_white_24dp"
            android:visibility="gone"
            app:backgroundTint="@color/colorFAB2"
            app:elevation="6dp"
            app:pressedTranslationZ="12dp"
            app:fabSize="mini"
            android:scaleX="0.0"
            android:scaleY="0.0"
            android:alpha="0.0"
            app:layout_anchor="@id/app_bar"
            app:layout_anchorGravity="bottom|end"/>

        <android.support.design.widget.FloatingActionButton
            android:id="@+id/fab_ders"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_margin="@dimen/fab_margin"
            android:src="@drawable/ic_add"
            app:backgroundTint="@color/colorFAB2"
            app:elevation="6dp"
            app:pressedTranslationZ="12dp"
            app:layout_anchor="@id/app_bar"
            app:layout_anchorGravity="bottom|end"/>

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

    <include layout="@layout/nav_view"/>

</android.support.v4.widget.DrawerLayout>

这就是我试图在视觉上实现的目标：