如何在Android上为SeekBar的拇指上色？

<shape xmlns:android="http://schemas.android.com/apk/res/android">
    <solid android:color="#FF0000" /> <!-- 设置拇指的颜色 -->
    <size android:width="20dp" android:height="20dp" /> <!-- 设置拇指的大小 -->
</shape>

<SeekBar
    android:id="@+id/seekBar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:thumb="@drawable/seekbar_thumb" />

SeekBar seekBar = findViewById(R.id.seekBar);
seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
    @Override
    public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
        Drawable thumb = seekBar.getThumb();
        thumb.setColorFilter(Color.RED, PorterDuff.Mode.SRC_IN); // 设置拇指的颜色
    }

    @Override
    public void onStartTrackingTouch(SeekBar seekBar) {
    }

    @Override
    public void onStopTrackingTouch(SeekBar seekBar) {
    }
});