可能大家都知道我們保存相冊到Android手機的時候,然后去打開系統圖庫找不到我們想要的那張圖片,那是因為我們插入的圖片還沒有更新的緣故,先講解下插入系統圖庫的方法吧,很簡單,一句代碼就能實現
- MediaStore.Images.Media.insertImage(getContentResolver(), mBitmap, "", "");
通過上面的那句代碼就能插入到系統圖庫,這時候有一個問題,就是我們不能指定插入照片的名字,而是系統給了我們一個當前時間的毫秒數為名字,有一個問題郁悶了很久,我還是先把insertImage的源碼貼出來吧
- /**
- * Insert an image and create a thumbnail for it.
- *
- * @param cr The content resolver to use
- * @param source The stream to use for the image
- * @param title The name of the image
- * @param description The description of the image
- * @return The URL to the newly created image, or <code>null</code> if the image failed to be stored
- * for any reason.
- */
- public static final String insertImage(ContentResolver cr, Bitmap source,
- String title, String description) {
- ContentValues values = new ContentValues();
- values.put(Images.Media.TITLE, title);
- values.put(Images.Media.DESCRIPTION, description);
- values.put(Images.Media.MIME_TYPE, "image/jpeg");
- Uri url = null;
- String stringUrl = null; /* value to be returned */
- try {
- url = cr.insert(EXTERNAL_CONTENT_URI, values);
- if (source != null) {
- OutputStream imageOut = cr.openOutputStream(url);
- try {
- source.compress(Bitmap.CompressFormat.JPEG, 50, imageOut);
- } finally {
- imageOut.close();
- }
- long id = ContentUris.parseId(url);
- // Wait until MINI_KIND thumbnail is generated.
- Bitmap miniThumb = Images.Thumbnails.getThumbnail(cr, id,
- Images.Thumbnails.MINI_KIND, null);
- // This is for backward compatibility.
- Bitmap microThumb = StoreThumbnail(cr, miniThumb, id, 50F, 50F,
- Images.Thumbnails.MICRO_KIND);
- } else {
- Log.e(TAG, "Failed to create thumbnail, removing original");
- cr.delete(url, null, null);
- url = null;
- }
- } catch (Exception e) {
- Log.e(TAG, "Failed to insert image", e);
- if (url != null) {
- cr.delete(url, null, null);
- url = null;
- }
- }
- if (url != null) {
- stringUrl = url.toString();
- }
- return stringUrl;
- }
上面方法里面有一個title,我剛以為是可以設置圖片的名字,設置一下,原來不是,郁悶,哪位高手知道title這個字段是干嘛的,告訴下小弟,不勝感激!
當然Android還提供了一個插入系統相冊的方法,可以指定保存圖片的名字,我把源碼貼出來吧
- /**
- * Insert an image and create a thumbnail for it.
- *
- * @param cr The content resolver to use
- * @param imagePath The path to the image to insert
- * @param name The name of the image
- * @param description The description of the image
- * @return The URL to the newly created image
- * @throws FileNotFoundException
- */
- public static final String insertImage(ContentResolver cr, String imagePath,
- String name, String description) throws FileNotFoundException {
- // Check if file exists with a FileInputStream
- FileInputStream stream = new FileInputStream(imagePath);
- try {
- Bitmap bm = BitmapFactory.decodeFile(imagePath);
- String ret = insertImage(cr, bm, name, description);
- bm.recycle();
- return ret;
- } finally {
- try {
- stream.close();
- } catch (IOException e) {
- }
- }
- }
啊啊,貼完源碼我才發現,這個方法調用了第一個方法,這個name就是上面方法的title,暈死,這下更加郁悶了,反正我設置title無效果,求高手為小弟解答,先不管了,我們繼續往下說
上面那段代碼插入到系統相冊之后還需要發條廣播
- sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED, Uri.parse("file://"+ Environment.getExternalStorageDirectory())));
上面那條廣播是掃描整個sd卡的廣播,如果你sd卡里面東西很多會掃描很久,在掃描當中我們是不能訪問sd卡,所以這樣子用戶體現很不好,用過微信的朋友都知道,微信保存圖片到系統相冊並沒有掃描整個SD卡,所以我們用到下面的方法
- Intent intent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
- Uri uri = Uri.fromFile(new File("/sdcard/image.jpg"));
- intent.setData(uri);
- mContext.sendBroadcast(intent);
或者用MediaScannerConnection
- final MediaScannerConnection msc = new MediaScannerConnection(mContext, new MediaScannerConnectionClient() {
- public void onMediaScannerConnected() {
- msc.scanFile("/sdcard/image.jpg", "image/jpeg");
- }
- public void onScanCompleted(String path, Uri uri) {
- Log.v(TAG, "scan completed");
- msc.disconnect();
- }
- });
也行你會問我,怎么獲取到我們剛剛插入的圖片的路徑?呵呵,這個自有方法獲取,insertImage(ContentResolver cr, Bitmap source,String title, String description),這個方法給我們返回的就是插入圖片的Uri,我們根據這個Uri就能獲取到圖片的絕對路徑
- private String getFilePathByContentResolver(Context context, Uri uri) {
- if (null == uri) {
- return null;
- }
- Cursor c = context.getContentResolver().query(uri, null, null, null, null);
- String filePath = null;
- if (null == c) {
- throw new IllegalArgumentException(
- "Query on " + uri + " returns null result.");
- }
- try {
- if ((c.getCount() != 1) || !c.moveToFirst()) {
- } else {
- filePath = c.getString(
- c.getColumnIndexOrThrow(MediaColumns.DATA));
- }
- } finally {
- c.close();
- }
- return filePath;
- }
根據上面的那個方法獲取到的就是圖片的絕對路徑,這樣子我們就不用發送掃描整個SD卡的廣播了,呵呵,寫到這里就算是寫完了,寫的很亂,希望大家將就的看下,希望對你有幫助!