onClick在onclick觸發兩次點擊後，即當我點擊第三次按OK按鈕時觸發

Question

大家好我收到一個錯誤，onClick在點擊兩次後觸發，我希望它在第一次點擊時執行。在這段代碼中，我用一個日期選擇器來顯示日期，在用戶選擇一個日期並按下確定按鈕時，該日期必須在TextView中顯示。

這是我的代碼

public class TimePicker extends Activity{ 
protected static OnDateChangedListener OnDateChangedListener; 
private int year; 
private int month; 
private int day; 
private String Date; 
@Override 
public void onCreate(Bundle savedInstanceState){ 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.time_picker); 
    Calendar cal = Calendar.getInstance(); 
    year = cal.get(Calendar.YEAR); 
    month = cal.get(Calendar.MONTH); 
    day = cal.get(Calendar.DAY_OF_MONTH); 
    final DatePicker dp = (DatePicker) findViewById(R.id.datePicker1);  


    Button b = (Button) findViewById(R.id.btnOk); 
    b.setOnClickListener(new OnClickListener() { 

     @Override 
     public void onClick(View v) { 
      // TODO Auto-generated method stub 
      OnDateChangedListener = new OnDateChangedListener() { 
       @Override 
       public void onDateChanged(DatePicker v, int selectedYear, int selectedMonth, int selectedDay) { 
        // TODO Auto-generated method stub 
        year = selectedYear; 
        month = selectedMonth; 
        day = selectedDay; 
       } 
      }; 
      dp.init(year, month, day, OnDateChangedListener); 
      StringBuilder sb = new StringBuilder(); 
      sb.append(day).append("-").append(month+1).append("-").append(year); 
      Date = sb.toString(); 
      TextView txt = (TextView) findViewById(R.id.textViewTime); 
      txt.setText(Date); 
     } 
    }); 

}}

Answer 1

移動以下OnDateChangedListener實例化這條線dp.init(year, month, day, OnDateChangedListener);。它會在第一次啓動時被第二次調用。

您還應將txt放入一個字段中，並在OnDateChanged之內調用setText後指定Date其新值。在onClick內刪除對setText的呼叫。

private void displayDate() { 
    StringBuilder sb = new StringBuilder(); 
      sb.append(day).append("-").append(month+1).append("-").append(year); 
    Date = sb.toString(); 
    TextView txt = (TextView) findViewById(R.id.textViewTime); 
    txt.setText(Date); 
}