特殊的需求造就特殊的功能

有的付費頁面是不能讓用戶截屏分享的,所以...我們就流氓的攔截掉并且刪除

實現(xiàn)方式

• 1,注冊一個媒體庫內(nèi)容變化的ContentObserver
• 2,獲取到媒體文件,查看創(chuàng)建時間和現(xiàn)在時間的差值
• 3,刪除文件并且通知媒體庫

代碼如下

/**
 * Created by wangfei on 2016/8/1 19:02.
 * 攔截用戶截屏,并且刪除截屏文件
 */
public class ScreenshotContentObserver {

    private Context mContext;
    private HandlerThread handlerThread;
    private Handler handler;
    private static ScreenshotContentObserver instance;
    private static final String TAG = "WWW";
    private static final String EXTERNAL_CONTENT_URI_MATCHER =
            MediaStore.Images.Media.EXTERNAL_CONTENT_URI.toString();
    private static final String[] PROJECTION = new String[]{
            MediaStore.Images.Media.DISPLAY_NAME, MediaStore.Images.Media.DATA,
            MediaStore.Images.Media.DATE_ADDED
    };
    private static final String SORT_ORDER = MediaStore.Images.Media.DATE_ADDED + " DESC";
    private ContentResolver mContentResolver;
    private ContentObserver mContentObserver;

    private ScreenshotContentObserver(Context context) {
        mContext = context;
        handlerThread = new HandlerThread("content_observer");
        handlerThread.start();
        handler = new Handler(handlerThread.getLooper()) {

            @Override
            public void handleMessage(Message msg) {
                super.handleMessage(msg);
                //刪除截屏
                ((File)msg.obj).delete();
                // 最后通知圖庫更新
                mContext.sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, Uri.fromFile((File)msg.obj)));
            }
        };
    }

    public static void startObserve(Context context) {
        if (instance == null) {
            instance = new ScreenshotContentObserver(context);
        }
        instance.register();
    }

    public static void stopObserve() {
        instance.unregister();
    }

    private void register() {
        mContentResolver = mContext.getContentResolver();
        mContentObserver = new ContentObserver(handler) {
            @Override
            public void onChange(boolean selfChange, Uri uri) {
                Log.d(TAG, "onChange: " + selfChange + ", " + uri.toString());
                if (uri.toString().matches(EXTERNAL_CONTENT_URI_MATCHER)) {
                    Cursor cursor = null;
                    try {
                        cursor = mContentResolver.query(uri, PROJECTION, null, null, SORT_ORDER);
                        if (cursor != null && cursor.moveToFirst()) {
                            String path = cursor.getString(cursor.getColumnIndex(MediaStore.Images.Media.DATA));
                            long dateAdded = cursor.getLong(cursor.getColumnIndex(MediaStore.Images.Media.DATE_ADDED));
                            long currentTime = System.currentTimeMillis();
                            Log.d(TAG, "path: " + path + ", dateAdded: " + dateAdded + ", currentTime: " + currentTime);
                            Log.d(TAG, "matchPath(path): " + matchPath(path) + ", matchAddTime(dateAdded): " +
                                    matchAddTime(dateAdded) + ", matchSize(path): " + matchSize(path));
                            if (matchPath(path) && matchAddTime(dateAdded)) {
                                // screenshot added!
                                File file = new File(path);
                                Message message=Message.obtain();
                                message.obj=file;
                                //解決華為手機無法刪除截屏問題
                                handler.sendMessageDelayed(message,250);
                            }
                        }
                    } catch (Exception e) {
                        Log.d(TAG, "Exception" + e.toString());
                    } finally {
                        if (cursor != null) {
                            cursor.close();
                        }
                    }
                }
                super.onChange(selfChange, uri);
            }
        };
        mContentResolver.registerContentObserver(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, true,
                mContentObserver);
    }

    private void unregister() {
        mContext.getContentResolver().unregisterContentObserver(mContentObserver);
    }


    /**
     * 添加時間與當(dāng)前時間不超過1.5s,大部分時候不超過1s瘟斜。
     *
     * @param addTime 圖片添加時間，單位:秒
     */
    private boolean matchAddTime(long addTime) {
        return System.currentTimeMillis() - addTime * 1000 < 1500;
    }

    /**
     * 尺寸不大于屏幕尺寸
     */
    private boolean matchSize(String filePath) {
        int w = ScreenUtil.getScreenWidth(mContext);
        int h = ScreenUtil.getScreenWidth(mContext);

        BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeFile(filePath, options);

        return w >= options.outWidth && h >= options.outHeight;
    }

    /**
     * 已調(diào)查的手機截屏圖片的路徑中帶有screenshot
     */
    private boolean matchPath(String filePath) {
        String lower = filePath.toLowerCase();
        return lower.contains("screenshot");
    }

}

使用方式(Activity中)

    protected void onStart() {
        super.onStart();
        ScreenshotContentObserver.startObserve(this);
    }



    protected void onStop() {
        super.onStop();
        ScreenshotContentObserver.stopObserve();
    }

最重要的一步

加權(quán)限

android.permission.READ_EXTERNAL_STORAGE

搞定..........