警報對話框不顯示

Question

大家好，我正在通過單擊按鈕在android中創建一個警報對話框。我使用XML的onClick屬性和調用函數。我的代碼是

public void selectPhoneType(View view) 
{ 
    String [] item = {"Home", "Work", "Mobile", "Work Fax", "Home Fax", "Pager", "Other", "Custom"}; 
    AlertDialog.Builder builder = new AlertDialog.Builder(getApplicationContext()); 
    builder.setTitle("Select Label"); 
    AlertDialog alert = builder.create(); 
    alert.show();} 

但是這個代碼不顯示警告，並給予錯誤，如

BadTokenException: Unable to add window -- token null is not for an application. 

請告訴我，什麼是錯的這個代碼。

Answer 1

new AlertDialog.Builder(getApplicationContext()); 

我認爲這是問題所在。您是否嘗試過：

new AlertDialog.Builder(YourActivityClassName.this);