应用内截屏的代码，在Activity中测试可用

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

    <ImageView
        android:id="@+id/imageView"
        android:layout_width="fill_parent"
        android:layout_height="350dip" 
        android:src="@drawable/right"/>

    <Button
        android:id="@+id/shotButton"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="shot" />

</LinearLayout>

package com.kale.floattest;

import android.R.color;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.drawable.BitmapDrawable;
import android.os.Bundle;
import android.view.Display;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;

public class MainActivity extends Activity {

    private Button shotButton;
    private ImageView imageView;
    BitmapDrawable bd;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        shotButton = (Button) findViewById(R.id.shotButton);
        imageView = (ImageView) findViewById(R.id.imageView);
        shotButton.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {

                 imageView.setImageBitmap(shot());
            }
        });
        //startService(new Intent(MainActivity.this, TestService.class));
    }

    /**
     * 截屏方法
     * 
     * @return
     */
    private Bitmap shot() {
        View view = getWindow().getDecorView();
        Display display = this.getWindowManager().getDefaultDisplay();
        view.layout(0, 0, display.getWidth(), display.getHeight());
        view.setDrawingCacheEnabled(true);// 允许当前窗口保存缓存信息，这样getDrawingCache()方法才会返回一个Bitmap
        Bitmap bmp = Bitmap.createBitmap(view.getDrawingCache());
        return bmp;
    }
}