警报对话框不显示

Question

大家好，我正在通过单击按钮在android中创建一个警报对话框。我使用XML的onClick属性和调用函数。我的代码是

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();} 

但是这个代码不显示警告，并给予错误，如

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

请告诉我，什么是错的这个代码。

Answer 1

new AlertDialog.Builder(getApplicationContext()); 

我认为这是问题所在。您是否尝试过：

new AlertDialog.Builder(YourActivityClassName.this);