file.length回報android系統

Question

總是0我想檢查文件的大小，我只有URI content://media/external/video/media/813 獲取文件的大小我用：

File file=new File(uri.getPath()); 
        long ls = file.length(); 

，並始終得到0。任何想法？

Answer 1

試試這個，下面的代碼

String[] filePathColumn = {MediaStore.Images.Media.DATA}; 
Cursor cursor = context.getContentResolver().query(uri, filePathColumn, null, null, null); 
cursor.moveToFirst(); 
int columnIndex = cursor.getColumnIndex(filePathColumn[0]); 
String filePath = cursor.getString(columnIndex); 
cursor.close(); 

File file = new File(filePath); 
long ls = file.length(); 

Answer 2

嘗試讓你的文件的長度

Cursor returnCursor = 
       getContentResolver().query(uri, null, null, null, null); 
     int sizeIndex = returnCursor.getColumnIndex(OpenableColumns.SIZE); 
     returnCursor.moveToFirst(); 
     int size = (int) returnCursor.getLong(sizeIndex);