可能大家都知道我们保存相册到Android手机的时候,然后去打开系统图库找不到我们想要的那张图片,那是因为我们插入的图片还没有更新的缘故,先讲解下插入系统图库的方法吧,很简单,一句代码就能实现
MediaStore.Images.Media.insertImage(getContentResolver(), mBitmap, "", "");
通过上面的那句代码就能插入到系统图库,这时候有一个问题,就是我们不能指定插入照片的名字,而是系统给了我们一个当前时间的毫秒数为名字,有一个问题郁闷了很久,我还是先把insertImage的源码贴出来吧
/** * 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; }
上面方法里面有一个title,我刚以为是可以设置图片的名字,设置一下,原来不是,郁闷,哪位高手知道title这个字段是干嘛的,告诉下小弟,不胜感激!
当然Android还提供了一个插入系统相册的方法,可以指定保存图片的名字,我把源码贴出来吧
/** * 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,贴完源码我才发现,这个方法调用了第一个方法,这个name就是上面方法的title,晕死,这下更加郁闷了,反正我设置title无效果,求高手为小弟解答,先不管了,我们继续往下说
上面那段代码插入到系统相册之后还需要发条广播
sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED, Uri.parse("file://"+ Environment.getExternalStorageDirectory())));
上面那条广播是扫描整个sd卡的广播,如果你sd卡里面东西很多会扫描很久,在扫描当中我们是不能访问sd卡,所以这样子用户体现很不好,用过微信的朋友都知道,微信保存图片到系统相册并没有扫描整个SD卡,所以我们用到下面的方法
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(); } });
也行你会问我,怎么获取到我们刚刚插入的图片的路径?呵呵,这个自有方法获取,insertImage(ContentResolver cr, Bitmap source,String title, String description),这个方法给我们返回的就是插入图片的Uri,我们根据这个Uri就能获取到图片的绝对路径
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; }
根据上面的那个方法获取到的就是图片的绝对路径,这样子我们就不用发送扫描整个SD卡的广播了,呵呵,写到这里就算是写完了,写的很乱,希望大家将就的看下,希望对你有帮助!