Android问题集锦：not allowed to send broadcast android.intent.action.MEDIA_MOUNTED

当我们保存图片后就会发个通知告诉系统让sdcard重新挂载，这样其他程序就会立即找到这张图片。

            Intent intent = new Intent();
            intent.setAction(Intent.ACTION_MEDIA_MOUNTED);
            intent.setData(Uri.fromFile(Environment
                    .getExternalStorageDirectory()));
            sendBroadcast(intent);

在清单文件中即使配置了：<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/> 也没有用，这是因为到了Android4.4，Google将MEDIA_MOUNTED的权限提高了，于是就报了一个下面的错误。

W/System.err﹕java.lang.SecurityException: Permission Denial: not allowed to send broadcast android.intent.action.MEDIA_MOUNTED from pid=18338, uid=10087

在stackoverfollow中找到了一个办法，在高版本中使用ACTION_MEDIA_SCANNER_SCAN_FILE去通知系统重新扫描文件。代码如下：

public void save(View v){		
		FileOutputStream stream;
		try {
			File file = new File(Environment.getExternalStorageDirectory(),"paint.png");
			stream = new FileOutputStream(file);
			boolean compress = bmCopy.compress(CompressFormat.PNG, 100, stream );
			KJLoger.debug("是否成功："+compress);
			Intent intent = new Intent();
		if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
			intent.setAction( Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);		
			intent.setData(Uri.fromFile(file));
		}else{
			intent.setAction(Intent.ACTION_MEDIA_MOUNTED);
			intent.setData(Uri.fromFile(Environment.getExternalStorageDirectory()));
		}
		sendBroadcast(intent);
	} catch (FileNotFoundException e) {
		e.printStackTrace();
	}
	
	 
}</pre>

至此，问题解决。