如何從函數返回所有值

Question

我想從此函數返回dbManagement.ORIGINATING_ADDRESS的所有值，但它只是給我blockedNumber的最後一個值。我知道它會給最後一個價值，但我怎麼能得到所有的價值。好心幫

public String selectBlockedNumbers() { 
     Cursor cursor = dbManagement.selectBlockedNumbers(); 
     String blockedNumber = null; 
     cursor.moveToFirst(); 
     for(int i = 0; i < cursor.getCount(); i++) { 
      blockedNumber = cursor.getString(cursor.getColumnIndex(dbManagement.ORIGINATING_ADDRESS)); 
      cursor.moveToNext(); 
     } 

     Toast.makeText(this, blockedNumber, Toast.LENGTH_LONG).show(); 
     return blockedNumber; 

    } 

在

Cursor cursor = dbManagement.selectBlockedNumbers(); 

功能selectBlockedNumbers（）由以下查詢：

cursor = db.rawQuery("SELECT " + ORIGINATING_ADDRESS + " FROM " + TABLE_BLOCK_LIST, null);

Answer 1

當for循環運行的最後一次，blockedNumbers將包含最後檢索的數字。所以，而不是返回String，而是返回List<String>。在這種情況下，您的代碼應更改爲

public List<String> selectBlockedNumbers() { 
     Cursor cursor = dbManagement.selectBlockedNumbers(); 
     List<String> blockedNumbers = new ArrayList<String>(); 
     cursor.moveToFirst(); 
     for(int i = 0; i < cursor.getCount(); i++) { 
      String blockedNumber = cursor.getString(cursor.getColumnIndex(dbManagement.ORIGINATING_ADDRESS)); 
      blockedNumbers.add(blockedNumber); 
      cursor.moveToNext(); 
     } 

     Toast.makeText(this, blockedNumber, Toast.LENGTH_LONG).show(); 
     return blockedNumbers;  
    }