前段时间在网上看到这么个例子是将view映射到一个bitmap中，稍加改进可以用于一些截图工具或者截图软件（QQ截图之类），例子写的不够完善，不过很有些学习的意义内容大致如下：
在Android中自有获取view中的cache内容，然后将内容转换成bitmap，方法名是：getDrawingCache(),返回结果为Bitmap，但是刚开始使用的时候，得到的结果都是null，所以在一个论坛里查到了正确的使用方法.代码如下：
contentLayout.setDrawingCacheEnabled(true);
contentLayout.measure(
MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED),
MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
contentLayout.layout(0, 0, contentLayout.getMeasuredWidth(),
contentLayout.getMeasuredHeight());
contentLayout.buildDrawingCache();
Bitmap bitmap= contentLayout.getDrawingCache();
在使用的时候调用
Bitmap bitmap = view.getDrawingCache();
就可以得到图片的bitmap了。
为了测试这个功能，作者使用了两种方式来创建LinerLayout中的内容，一种是在xml文件中就将view的内容添加了，只需在代码中添加对应ImageView中的图片就行了；另一种是动态添加LinerLayout中的View。
setview的代码：
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.set_view);
contentLayout = (LinearLayout) findViewById(R.id.content);
imgSource1 = (ImageView) findViewById(R.id.imgSource1);
imgSource2 = (ImageView) findViewById(R.id.imgSource2);
imgCache = (ImageView) findViewById(R.id.imgCache);
imgSource1.setImageResource(R.drawable.source1);
imgSource2.setImageResource(R.drawable.source2);
contentLayout.setDrawingCacheEnabled(true);
contentLayout.measure(
MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED),
MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
contentLayout.layout(0, 0, contentLayout.getMeasuredWidth(),
contentLayout.getMeasuredHeight());
contentLayout.buildDrawingCache();
Bitmap bitmap= contentLayout.getDrawingCache();
if(bitmap!=null){
imgCache.setImageBitmap(bitmap);
}else{
Log.i("CACHE_BITMAP", "DrawingCache=null");
}
}
第二种方法代码：
private void addRelativeLayout() {
// TODO Auto-generated method stub
RelativeLayout.LayoutParams layoutpare = new RelativeLayout.LayoutParams(
LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT);
RelativeLayout relativeLayout = new RelativeLayout(this);
relativeLayout.setLayoutParams(layoutpare);
ImageView imgView1 = new ImageView(this);
ImageView imgView2 = new ImageView(this);
imgView1.setImageResource(R.drawable.source1);
imgView2.setImageResource(R.drawable.source2);
RelativeLayout.LayoutParams img1 = new RelativeLayout.LayoutParams(38,
38);
img1.addRule(RelativeLayout.ALIGN_PARENT_LEFT, RelativeLayout.TRUE);
RelativeLayout.LayoutParams img2 = new RelativeLayout.LayoutParams(38,
38);
img2.addRule(RelativeLayout.ALIGN_PARENT_RIGHT, RelativeLayout.TRUE);
relativeLayout.addView(imgView1, img1);
relativeLayout.addView(imgView2, img2);
addViewContent.addView(relativeLayout);
}
/**
* 添加图片源
*/
private void addImgSource() {
ImageView imgView1 = new ImageView(this);
ImageView imgView2 = new ImageView(this);
imgView1.setImageResource(R.drawable.source1);
imgView2.setImageResource(R.drawable.source2);
addViewContent.addView(imgView1, new LayoutParams(
LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT));
addViewContent.addView(imgView2, new LayoutParams(
LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT));
}