无法自定义EditText的外观选择景观上的手柄/锚点

我很难自定义EditText选择句柄。我正在关注此线程：

如何更改EditText的颜色/外观选择句柄/锚点？

看起来很简单。但是，我无法在景观环境中使用它。谁能发现我在做什么错？我几乎在测试活动中粘贴了相同的代码，但锚点句柄始终相同。我尝试按照建议和编程方式使用样式。仍然我总是得到相同的默认蓝色锚点：(

我在牛轧糖上不确定是否会有所作为。

测试活动：

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setTheme(R.style.MyCustomTheme);
    setContentView(R.layout.activity_main);
    final EditText editText = (EditText) findViewById(R.id.edit1);
    // tried programatically too and no success
    try {
        final Field fEditor = TextView.class.getDeclaredField("mEditor");
        fEditor.setAccessible(true);
        final Object editor = fEditor.get(editText);
        final Field fSelectHandleLeft = editor.getClass().getDeclaredField("mSelectHandleLeft");
        final Field fSelectHandleRight =
                editor.getClass().getDeclaredField("mSelectHandleRight");
        final Field fSelectHandleCenter =
                editor.getClass().getDeclaredField("mSelectHandleCenter");
        fSelectHandleLeft.setAccessible(true);
        fSelectHandleRight.setAccessible(true);
        fSelectHandleCenter.setAccessible(true);
        fSelectHandleLeft.set(editor, ContextCompat.getDrawable(this, R.drawable.small_rect));
        fSelectHandleRight.set(editor, ContextCompat.getDrawable(this, R.drawable.small_rect));
        fSelectHandleCenter.set(editor, ContextCompat.getDrawable(this, R.drawable.small_rect));
    } catch (final Exception e) {
        Log.d("CUSTOM_ANCHORS", e.toString());
    }
}

布局：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <EditText
        android:id="@+id/edit1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:padding="10dp"
        android:text="Hello World"
        android:textSize="20sp" />

</LinearLayout>

我的风格：

<!-- Base application theme. -->
<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
    <!-- Customize your theme here. -->
    <item name="colorPrimary">@color/colorPrimary</item>
    <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
    <item name="colorAccent">@color/colorAccent</item>
</style>


<style name="MyCustomTheme" parent="@style/AppTheme">
    <item name="android:textSelectHandle">@drawable/small_rect</item>
    <item name="android:textSelectHandleLeft">@drawable/small_rect</item>
    <item name="android:textSelectHandleRight">@drawable/small_rect</item>
</style>

可绘制对象（small_rect.xml）

<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <size
        android:width="20dp"
        android:height="20dp" />
    <gradient
        android:angle="90"
        android:centerColor="#D6D6D6"
        android:endColor="#4B6CD6"
        android:startColor="#6586F0" />
    <corners android:radius="0dp" />
</shape>

结果：