可折叠工具栏-如何删除工具栏背景色

Question

在这种情况下，我必须将工具栏保持在顶部，因此我已使用样式进行了设置，而不是添加CollapsingToolbarLayout。我已应用顶部边距从工具栏移动顶部，否则地图被隐藏在工具栏后面。

由于此设置，向下滚动时出现黄色补丁（原色）。请看图片。

有什么办法可以消除这种颜色？或任何其他更好的方法来实现这一目标？

布局XML

<?xml version="1.0" encoding="utf-8"?>
<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="Fragments.Location">

    <android.support.design.widget.AppBarLayout
        android:id="@+id/app_bar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@android:color/transparent"
        android:fitsSystemWindows="true"
        android:theme="@style/ThemeOverlay.AppCompat.Light"
        app:elevation="0dp">

        <android.support.design.widget.CollapsingToolbarLayout
            android:id="@+id/toolbar_layout"
            android:layout_width="match_parent"
            android:layout_height="@dimen/location_height"
            android:layout_marginTop="?attr/actionBarSize"
            android:fitsSystemWindows="true"
            app:contentScrim="@android:color/transparent"
            app:expandedTitleGravity="top"
            app:expandedTitleTextAppearance="@android:color/transparent"
            app:layout_scrollFlags="scroll|exitUntilCollapsed|snap"
            app:titleEnabled="false">

            <!--
            TODO:: You may use fragment to load map just below the ImageView.
            The ImageView is a placeholder I used during the design as a reference.
             -->
            <ImageView
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:contentDescription="@string/app_name"
                android:scaleType="centerCrop"
                android:src="@drawable/gmap_screenshot"
                app:layout_collapseMode="pin" />


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

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


    <android.support.v4.widget.NestedScrollView
        android:id="@+id/location_nested_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:fillViewport="true"
        android:scrollbars="none"
        app:layout_behavior="@string/appbar_scrolling_view_behavior">

        <android.support.constraint.ConstraintLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:descendantFocusability="blocksDescendants"
            android:focusableInTouchMode="true">

            <android.support.design.widget.TabLayout
                android:id="@+id/location_tab_layout"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="@color/colorLightGray"
                android:elevation="@dimen/archive_card_elevation"
                app:layout_constraintBottom_toTopOf="@+id/location_viewpager"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintHorizontal_bias="0.5"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toTopOf="parent"
                app:layout_constraintVertical_bias="0.0"
                app:layout_constraintVertical_chainStyle="packed"
                app:tabSelectedTextColor="@color/colorWhite"
                app:tabTextColor="@color/colorFieldHint"
                tools:targetApi="lollipop">

                <!--
                TODO:: Remove the tab items ...
                I have kept it for your reference however it is useless here..
                as loading from Viewpager class..
                -->
                <android.support.design.widget.TabItem
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:text="Description" />

                <android.support.design.widget.TabItem
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:text="Items" />

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

            <android.support.v4.view.ViewPager
                android:id="@+id/location_viewpager"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                app:layout_behavior="@string/appbar_scrolling_view_behavior"
                app:layout_constraintBottom_toBottomOf="parent"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintHorizontal_bias="0.5"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toBottomOf="@+id/location_tab_layout" />

        </android.support.constraint.ConstraintLayout>

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

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