android 长布局截图（listView ScrollView）

产品经理需要将一个界面中部分内容截图后保存下来或者分享出去，基本思想是计算截图的view的宽高，新建一个包含bitmap（view大小的）的canvas，在canvas上绘制该view即可获取到bitmap

/**
* 截取scrollview的屏幕
*/
public static Bitmap getBitmapByView(ScrollView scrollView) {

int h = 0;
Bitmap bitmap = null;
// 获取listView实际高度
for (int i = 0; i < scrollView.getChildCount(); i++) {
h += scrollView.getChildAt(i).getHeight();
//    		scrollView.getChildAt(i).setBackgroundResource(R.drawable.bg3);
}
Log.d(TAG, "实际高度:" + h);
//    	Log.d(TAG, " 高度:" + scrollView.getHeight());
// 创建对应大小的bitmap
bitmap = Bitmap.createBitmap(scrollView.getWidth(), h,
Bitmap.Config.ARGB_8888);
final Canvas canvas = new Canvas(bitmap);
scrollView.draw(canvas);
// 测试输出
savePic(bitmap, "/sdcard/screen_test.png");
return bitmap;
}

/**
*  截图listview
*
*/
public static Bitmap getbBitmap(ListView listView) {
int h = 0;
Bitmap bitmap = null;
// 获取listView实际高度
for (int i = 0; i < listView.getChildCount(); i++) {
h += listView.getChildAt(i).getHeight();
}
Log.d(TAG, "实际高度:" + h);
Log.d(TAG, "list 高度:" + listView.getHeight());
// 创建对应大小的bitmap
bitmap = Bitmap.createBitmap(listView.getWidth(), h,
Bitmap.Config.ARGB_8888);
final Canvas canvas = new Canvas(bitmap);
listView.draw(canvas);
// 测试输出
savePic(bitmap, "/sdcard/screen_test.png");
return bitmap;
}

/**
*  获取指定Activity的截屏，保存到png文件
*/
public static Bitmap takeScreenShot(Activity activity) {
// View是你需要截图的View
View view = activity.getWindow().getDecorView();
view.setDrawingCacheEnabled(true);
view.buildDrawingCache();
Bitmap b1 = view.getDrawingCache();

// 获取状态栏高度
Rect frame = new Rect();
activity.getWindow().getDecorView().getWindowVisibleDisplayFrame(frame);
int statusBarHeight = frame.top;
System.out.println(statusBarHeight);

// 获取屏幕长和高
int width = activity.getWindowManager().getDefaultDisplay().getWidth();
int height = activity.getWindowManager().getDefaultDisplay()
.getHeight();
// 去掉标题栏
// Bitmap b = Bitmap.createBitmap(b1, 0, 25, 320, 455);
Bitmap b = Bitmap.createBitmap(b1, 0, statusBarHeight, width, height
- statusBarHeight);
view.destroyDrawingCache();
savePic(b, "/sdcard/screen_test.png");
return b;
}

/**
* 保存到sdcard
*/
public static void savePic(Bitmap b, String strFileName) {
FileOutputStream fos = null;
try {
fos = new FileOutputStream(strFileName);
if (null != fos) {
b.compress(Bitmap.CompressFormat.PNG, 90, fos);
fos.flush();
fos.close();
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}