Android 防止矢量图像变形

我有一个矢量图像作为动作条的背景，我的问题是，当动作条改变大小时，矢量会变形，动画看起来不自然。有没有办法防止这种情况

这是向量“bar\u left\u angle”：

这里是布局图：

<?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"
    android:id="@+id/main_content"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/grey"
    android:fitsSystemWindows="true">

    <android.support.design.widget.AppBarLayout
        android:id="@+id/productsBarLayout"
        android:layout_width="match_parent"
        android:layout_height="192dp"
        android:fitsSystemWindows="true"
        android:scaleType="fitXY"
        android:background="@drawable/bar_left_angle"
        app:elevation="0dp" >
        <android.support.design.widget.CollapsingToolbarLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:layout_scrollFlags="scroll|exitUntilCollapsed" >
            <android.support.v7.widget.Toolbar
                android:layout_height="?attr/actionBarSize"
                android:layout_width="match_parent"
                android:background="@drawable/bar_left_angle"
                app:layout_collapseMode="pin"/>
        </android.support.design.widget.CollapsingToolbarLayout>
    </android.support.design.widget.AppBarLayout>

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

<?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"
    android:id="@+id/main_content"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/grey"
    android:fitsSystemWindows="true">

    <android.support.design.widget.AppBarLayout
        android:id="@+id/productsBarLayout"
        android:layout_width="match_parent"
        android:layout_height="192dp"
        android:fitsSystemWindows="true"
        android:scaleType="fitXY"
        android:background="@drawable/bar_left_angle"
        app:elevation="0dp" >
        <android.support.design.widget.CollapsingToolbarLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:layout_scrollFlags="scroll|exitUntilCollapsed" >
            <android.support.v7.widget.Toolbar
                android:layout_height="?attr/actionBarSize"
                android:layout_width="match_parent"
                android:background="@drawable/bar_left_angle"
                app:layout_collapseMode="pin"/>
        </android.support.design.widget.CollapsingToolbarLayout>
    </android.support.design.widget.AppBarLayout>

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