Android截屏事件监听.doc

Android截屏事件监听1. 前言Android系统没有直接对截屏事件监听的接口，也没有广播，只能自己动手来丰衣足食，一般有三种方法。利用FileObserver监听某个目录中资源变化情况利用ContentObserver监听全部资源的变化监听截屏快捷按键由于厂商自定义Android系统的多样性，再加上快捷键的不同以及第三方应用，监听截屏快捷键这事基本不靠谱，可以直接忽略。本文使用的测试手机，一加2（One Plus 2)。2. FileObserver添加权限：代码示例：public class ScreenshotActivity extends AppCompatActivity private final String TAG = Screenshot; private static final String PATH = Environment.getExternalStorageDirectory() + File.separator + Environment.DIRECTORY_PICTURES + File.separator + Screenshots + File.separator; protected void onCreate(Nullable Bundle savedInstanceState) super.onCreate(savedInstanceState); setContentView(R.layout.activity_screenshot); mFileObserver = new CustomFileObserver(PATH); Override protected void onResume() super.onResume(); mFileObserver.startWatching(); Log.d(TAG, PATH); Override protected void onStop() super.onStop(); mFileObserver.stopWatching(); /* * 目录监听器 */ private class CustomFileObserver extends FileObserver private String mPath; public CustomFileObserver(String path) super(path); this.mPath = path; public CustomFileObserver(String path, int mask) super(path, mask); this.mPath = path; Override public void onEvent(int event, String path) Log.d(TAG, path + + event); / 监听到事件，做一些过滤去重处理操作 打印的日志：一加2D/Screenshot: Screenshot_2016-12-16-17-49-18.png 256D/Screenshot: Screenshot_2016-12-16-17-49-18.png 32D/Screenshot: Screenshot_2016-12-16-17-49-18.png 2D/Screenshot: Screenshot_2016-12-16-17-49-18.png 2D/Screenshot: Screenshot_2016-12-16-17-49-18.png 2D/Screenshot: Screenshot_2016-12-16-17-49-18.png 2D/Screenshot: Screenshot_2016-12-16-17-49-18.png 2D/Screenshot: Screenshot_2016-12-16-17-49-18.png 2D/Screenshot: Screenshot_2016-12-16-17-49-18.png 2D/Screenshot: Screenshot_2016-12-16-17-49-18.png 2D/Screenshot: Screenshot_2016-12-16-17-49-18.png 2D/Screenshot: Screenshot_2016-12-16-17-49-18.png 2D/Screenshot: Screenshot_2016-12-16-17-49-18.png 2D/Screenshot: Screenshot_2016-12-16-17-49-18.png 2D/Screenshot: Screenshot_2016-12-16-17-49-18.png 2D/Screenshot: Screenshot_2016-12-16-17-49-18.png 2D/Screenshot: Screenshot_2016-12-16-17-49-18.png 2D/Screenshot: Screenshot_2016-12-16-17-49-18.png 8三星 S4D/Screenshot: Screenshot_2016-12-16-19-01-08.png 256D/Screenshot: Screenshot_2016-12-16-19-01-08.png 32D/Screenshot: Screenshot_2016-12-16-19-01-08.png 2D/Screenshot: Screenshot_2016-12-16-19-01-08.png 2D/Screenshot: Screenshot_2016-12-16-19-01-08.png 2D/Screenshot: Screenshot_2016-12-16-19-01-08.png 2D/Screenshot: Screenshot_2016-12-16-19-01-08.png 2D/Screenshot: Screenshot_2016-12-16-19-01-08.png 2D/Screenshot: Screenshot_2016-12-16-19-01-08.png 2D/Screenshot: Screenshot_2016-12-16-19-01-08.png 2D/Screenshot: Screenshot_2016-12-16-19-01-08.png 2D/Screenshot: Screenshot_2016-12-16-19-01-08.png 2D/Screenshot: Screenshot_2016-12-16-19-01-08.png 2D/Screenshot: Screenshot_2016-12-16-19-01-08.png 2D/Screenshot: Screenshot_2016-12-16-19-01-08.png 2D/Screenshot: Screenshot_2016-12-16-19-01-08.png 2D/Screenshot: Screenshot_2016-12-16-19-01-08.png 2D/Screenshot: Screenshot_2016-12-16-19-01-08.png 2D/Screenshot: Screenshot_2016-12-16-19-01-08.png 2D/Screenshot: Screenshot_2016-12-16-19-01-08.png 2D/Screenshot: Screenshot_2016-12-16-19-01-08.png 2D/Screenshot: Screenshot_2016-12-16-19-01-08.png 8D/Screenshot: Screenshot_2016-12-16-19-01-08.png 32D/Screenshot: Screenshot_2016-12-16-19-01-08.png 16几点注意事项：每一次截屏，有多个事件回调每一次截屏，不同的手机，事件回调可能有些不同，参考上述日志不同的手机，默认截屏图片储存的文件夹可能不同FileObserver只能监听文件夹中子文件和子文件夹的变化情况，不能监听子文件夹内部的资源变化需要权限，否则可能收不到事件基于第三点和第四点，这种方法并不能适用于所有的机型。注意：如果自己写Demo没有收到事件，检查一下权限和监听的目录3. ContentObserverContentObserver用来监听指定uri的所有资源变化，我们可以用它来监听图片资源变化情况，然后做过滤。添加权限代码示例：public class ScreenshotActivity extends AppCompatActivity private static final String KEYWORDS = screenshot, screen_shot, screen-shot, screen shot, screencapture, screen_capture, screen-capture, screen capture, screencap, screen_cap, screen-cap, screen cap ; /* 读取媒体数据库时需要读取的列 */ private static final String MEDIA_PROJECTIONS = MediaStore.Images.ImageColumns.DATA, MediaStore.Images.ImageColumns.DATE_TAKEN, ; /* 内部存储器内容观察者 */ private ContentObserver mInternalObserver; /* 外部存储器内容观察者 */ private ContentObserver mExternalObserver; private HandlerThread mHandlerThread; private Handler mHandler; protected void onCreate(Nullable Bundle savedInstanceState) super.onCreate(savedInstanceState); setContentView(R.layout.activity_screenshot); mHandlerThread = new HandlerThread(Screenshot_Observer); mHandlerThread.start(); mHandler = new Handler(mHandlerThread.getLooper(); / 初始化 mInternalObserver = new MediaContentObserver(MediaStore.Images.Media.INTERNAL_CONTENT_URI, mHandler); mExternalObserver = new MediaContentObserver(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, mHandler); / 添加监听 this.getContentResolver().registerContentObserver( MediaStore.Images.Media.INTERNAL_CONTENT_URI, false, mInternalObserver ); this.getContentResolver().registerContentObserver( MediaStore.Images.Media.EXTERNAL_CONTENT_URI, false, mExternalObserver ); protected void onDestroy() super.onDestroy(); / 注销监听 this.getContentResolver().unregisterContentObserver(mInternalObserver); this.getContentResolver().unregisterContentObserver(mExternalObserver); private void handleMediaContentChange(Uri contentUri) Cursor cursor = null; try / 数据改变时查询数据库中最后加入的一条数据 cursor = this.getContentResolver().query( contentUri, MEDIA_PROJECTIONS, null, null, MediaStore.Images.ImageColumns.DATE_ADDED + desc limit 1 ); if (cursor = null) return; if (!cursor.moveToFirst() return; / 获取各列的索引 int dataIndex = cursor.getColumnIndex(MediaStore.Images.ImageColumns.DATA); int dateTakenIndex = cursor.getColumnIndex(MediaStore.Images.ImageColumns.DATE_TAKEN); / 获取行数据 String data = cursor.getString(dataIndex); long dateTaken = cursor.getLong(dateTakenIndex); / 处理获取到的第一行数据 handleMediaRowData(data, dateTaken); catch (Exception e) e.printStackTrace(); finally if (cursor != null & !cursor.isClosed() cursor.close(); /* * 处理监听到的资源 */ private void handleMediaRowData(String data, long dateTaken) if (checkScreenShot(data, dateTaken) Log.d(TAG, data + + dateTaken); else Log.d(TAG, Not screenshot event); /* * 判断是否是截屏 */ private boolean checkScreenShot(String data, long dateTaken) data = data.toLowerCase(); / 判断图片路径是否含有指定的关键字之一, 如果有, 则认为当前截屏了 for (String keyWork : KEYWORDS) if (data.contains(keyWork) return true; return false; /* * 媒体内容观察者(观察媒体数据库的改变) */