光標只輸出最後一個值

Question

日誌顯示所有的數據，但它只輸出textView中的最後一個值，關於爲什麼？

if (c.moveToFirst()) { 

     //Log to test cursor data 
     Log.i("Cursor", DatabaseUtils.dumpCursorToString(c)); 


     do { 
      String cow = c.getString(c.getColumnIndex("cow")); 
      String score = c.getString(c.getColumnIndex("score")); 

      textViewOutputcow.setText(cow + "\n"); 
      textViewOutputscore.setText(score + "\n"); 
     } while (c.moveToNext()); 

    } 
    c.close(); 

Answer 1

每次通過循環時，您都在設置文本內容，而不是添加到它。你可以使用一個StringBuffer像這樣做：

StringBuffer cowBuffer=new StringBuffer(); 
StringBuffer scoreBuffer=new StringBuffer(); 

do { 
    String cow = c.getString(c.getColumnIndex("cow")); 
    String score = c.getString(c.getColumnIndex("score")); 

    cowBuffer.append(cow + "\n"); 
    scoreBuffer.append(score + "\n"); 
    } 
while (c.moveToNext()); 


textViewOutputcow.setText(cowBuffer.toString()); 
textViewOutputscore.setText(scoreBuffer.toString()); 

Answer 2

這是因爲您在每次迭代後都不斷更新textview的內容。實際上，您只能看到光標中最後一行的值。