顾名思义，Android ScaleDrawable实现一个drawable的缩放。写一个例子。

一个线性布局，垂直放几个ImageView，然后依次缩放若干个ScaleDrawable。

布局文件：

Java代码：

package zhangphil.app;import android.graphics.Color;import android.graphics.drawable.ColorDrawable;import android.graphics.drawable.ScaleDrawable;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.view.Gravity;import android.widget.ImageView;public class MainActivity extends AppCompatActivity {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        ColorDrawable drawable1=new ColorDrawable(Color.RED);        drawable1.setLevel(1);        ImageView image1= (ImageView) findViewById(R.id.imageView1);        image1.setImageDrawable(drawable1);        ColorDrawable drawable2=new ColorDrawable(Color.YELLOW);        drawable2.setLevel(1);        ScaleDrawable sd2 = new ScaleDrawable(drawable2, Gravity.LEFT,0.1f,0.0f);        ImageView image2= (ImageView) findViewById(R.id.imageView2);        image2.setImageDrawable(sd2);        ColorDrawable drawable3=new ColorDrawable(Color.BLUE);        drawable3.setLevel(1);        ScaleDrawable sd3 = new ScaleDrawable(drawable3, Gravity.LEFT,0.2f,0.0f);        ImageView image3= (ImageView) findViewById(R.id.imageView3);        image3.setImageDrawable(sd3);        ColorDrawable drawable4=new ColorDrawable(Color.GREEN);        drawable4.setLevel(1);        ScaleDrawable sd4 = new ScaleDrawable(drawable4, Gravity.LEFT,0.3f,0.0f);        ImageView image4= (ImageView) findViewById(R.id.imageView4);        image4.setImageDrawable(sd4);    }}

代码运行结果：

以上ScaleDrawable没有让drawable的高度缩放，只缩放宽度。

附录：