android View的快照与屏幕的截屏

android webView的快照与屏幕的截屏。部分代码如下：

[html]

/**

* 截取webView可视区域的截图

* @param webView 前提：WebView要设置webView.setDrawingCacheEnabled(true);

* @return

*/

private Bitmap captureWebViewVisibleSize(WebView webView){

Bitmap bmp = webView.getDrawingCache();

return bmp;

}

/**

* 截取webView可视区域的截图

* @param webView 前提：WebView要设置webView.setDrawingCacheEnabled(true);

* @return

*/

private Bitmap captureWebViewVisibleSize(WebView webView){

Bitmap bmp = webView.getDrawingCache();

return bmp;

}

这个方法只截取屏幕中显示出来部分的webView画面，未显示的部分不会被截取。

[html]

/**

* 截取webView快照(webView加载的整个内容的大小)

* @param webView

* @return

*/

private Bitmap captureWebView(WebView webView){

Picture snapShot = webView.capturePicture();

Bitmap bmp = Bitmap.createBitmap(snapShot.getWidth(),snapShot.getHeight(), Bitmap.Config.ARGB_8888);

Canvas canvas = new Canvas(bmp);

snapShot.draw(canvas);

return bmp;

}

/**

* 截取webView快照(webView加载的整个内容的大小)

* @param webView

* @return

*/ www.2cto.com

private Bitmap captureWebView(WebView webView){

Picture snapShot = webView.capturePicture();

Bitmap bmp = Bitmap.createBitmap(snapShot.getWidth(),snapShot.getHeight(), Bitmap.Config.ARGB_8888);

Canvas canvas = new Canvas(bmp);

snapShot.draw(canvas);

return bmp;

}

这个看好与上一个是不同的，他是截取webView的整个页面，未显示的也会被截取。

[html]

/**

* 截屏

* @param context

* @return

*/

private Bitmap captureScreen(Activity context){

View cv = context.getWindow().getDecorView();

Bitmap bmp = Bitmap.createBitmap(cv.getWidth(), cv.getHeight(),Config.ARGB_8888);

Canvas canvas = new Canvas(bmp);

cv.draw(canvas);

return bmp;

}

/**

* 截屏

* @param context

* @return

*/

private Bitmap captureScreen(Activity context){

View cv = context.getWindow().getDecorView();

Bitmap bmp = Bitmap.createBitmap(cv.getWidth(), cv.getHeight(),Config.ARGB_8888);

Canvas canvas = new Canvas(bmp);

cv.draw(canvas);

return bmp;

}

/**
* 截取可见屏幕部分的view视图
* @param activity
* @return
*/
public static Bitmap shotScreen(Activity activity) {
View view = activity.getWindow().getDecorView();
Display display = activity.getWindowManager().getDefaultDisplay();
view.layout(0, 0, display.getWidth(), display.getHeight());
// 允许当前窗口保存缓存信息，这样getDrawingCache()方法才会返回一个Bitmap
view.setDrawingCacheEnabled(true);
Bitmap bmp = Bitmap.createBitmap(view.getDrawingCache());
return bmp;
}

看看下面例子：
/**
* 此demo实现了截屏并将截图放到指定的控件上缩放显示
* 技术要点：
* 1.截屏
* 2.缩放功能
* @author: 严程
* @CreateDate: 2012-08-09
*/
public class Demo4Activity extends Activity {
private Button but;
private ImageButton img;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
but = (Button)findViewById(R.id.but);
but.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// 实现截屏
View view = Demo4Activity.this.getWindow().getDecorView();
// 启动缓存
view.setDrawingCacheEnabled(true);
// 接收数据
Bitmap bitmap = view.getDrawingCache();
img.setImageBitmap(zoomBitmap(bitmap));

}
});
img = (ImageButton)findViewById(R.id.img);
img.setBackgroundColor(Color.RED);
}


/**
* 实现图缩放
* @param target
* @return
*/
public Bitmap zoomBitmap(Bitmap target){
// 得到图片的高宽
int width = target.getWidth();
int height = target.getHeight();
Matrix matrix = new Matrix();
// 算出图片的高宽缩放比例
float scaleWidth = ((float)300)/ width;
float scaleHeight = ((float)300)/ height;
matrix.postScale(scaleWidth, scaleHeight);
// Bitmap result = Bitmap.createBitmap(target,0,0,width,height, matrix,true);
return Bitmap.createBitmap(target,0,0,width,height, matrix,true);
}

}