CollapsingToolbarLayout中的内容被工具栏背景颜色遮盖

Question

I'm seeing an issue with my app when using the Android design support library in that the CollapsingToolbarLayout appears to have a theme-coloured background bar at the top, even when there is enough space (and therefore it should be 'transparent').

Any ideas what I'm doing wrong?

<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto" android:id="@+id/main_content"
android:layout_width="match_parent" android:layout_height="match_parent"
android:fitsSystemWindows="true" tools:context=".MainActivity">

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

    <android.support.design.widget.CollapsingToolbarLayout
        android:id="@+id/collapsing_toolbar"
        android:layout_width="match_parent"
        android:layout_height="400dp"
        android:fitsSystemWindows="true"
        app:contentScrim="?attr/colorPrimary"
        app:expandedTitleMarginEnd="64dp"
        app:expandedTitleMarginStart="48dp"
        app:layout_scrollFlags="scroll|exitUntilCollapsed">


        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:scaleType="centerCrop"
            android:fitsSystemWindows="true"
            app:layout_collapseMode="parallax">
            <fragment
                android:layout_width="match_parent"
                android:layout_height="match_parent" android:id="@+id/map"
                android:name="com.google.android.gms.maps.SupportMapFragment"
                />

            <FrameLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:background="#66000000"
                android:layout_alignParentTop="true"
                android:layout_alignParentLeft="true"
                android:layout_alignParentStart="true" />
        </RelativeLayout>

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

        </android.support.v7.widget.Toolbar>

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

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

<android.support.v4.widget.NestedScrollView
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior">
  <!-- content -->
</android.support.v4.widget.NestedScrollView>
</android.support.design.widget.CoordinatorLayout>

Answer 1

I'm having very similar layout in my app and it's working well for me. Comparing mine layout to yours, my guess is you should remove background attribute from your Toolbar . Furthermore, I use one of the default themes for Toolbar (@style/ThemeOverlay.AppCompat.Dark). I see you're using your own theme, which might be causing problem as well. (I set StatusBar color to transparent in Java code, if you're interested in that too).