Android中本地图片地址和Uri的相互装换

    //绝对路径转uri
    private static Uri getImageContentUri(Context context, java.io.File imageFile) {
        String filePath = imageFile.getAbsolutePath();
        Cursor cursor = context.getContentResolver().query(MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
                new String[]{MediaStore.Images.Media._ID}, MediaStore.Images.Media.DATA + "=? ",
                new String[]{filePath}, null);
        if (cursor != null && cursor.moveToFirst()) {
            int id = cursor.getInt(cursor.getColumnIndex(MediaStore.MediaColumns._ID));
            Uri baseUri = Uri.parse("content://media/external/images/media");
            return Uri.withAppendedPath(baseUri, "" + id);
        } else {
            if (imageFile.exists()) {
                ContentValues values = new ContentValues();
                values.put(MediaStore.Images.Media.DATA, filePath);
                return context.getContentResolver().insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);
            } else {
                return null;
            }
        }
    }

    // uri转绝对路径 
    public static String getFilePathFromContentUri(Uri selectedVideoUri, ContentResolver contentResolver) {  
        String filePath;  
        String[] filePathColumn = {MediaStore.MediaColumns.DATA};  
  
        Cursor cursor = contentResolver.query(selectedVideoUri, filePathColumn, null, null, null);  
//      也可用下面的方法拿到cursor  
//      Cursor cursor = this.context.managedQuery(selectedVideoUri, filePathColumn, null, null, null);  
  
        cursor.moveToFirst();  
  
        int columnIndex = cursor.getColumnIndex(filePathColumn[0]);  
        filePath = cursor.getString(columnIndex);  
        cursor.close();  
        return filePath;  
    }