Android 将Logcat信息保存到文件

File filename = new File(Environment.getExternalStorageDirectory()+"/mylog.log");
        try {
            filename.createNewFile();
            String cmd = "logcat -d -f"+filename.getAbsolutePath();
            Runtime.getRuntime().exec(cmd);
        } catch (IOException e) {
            e.printStackTrace();
        }