java - Alert Builder 我错过了什么

Question

我正在尝试在单击的按钮下的 BaseAdapter 中添加 Alert Builder。这是我的代码

 Button btn=(Button)vi.findViewById(R.id.btnAdd);
 btn.setOnClickListener(new OnClickListener(){

                             AlertDialog.Builder dialogBox=new AlertDialog.Builder(this);
                 dialogBox.setPositiveButton("Yes", new DialogInterface.OnClickListener(){
                       public void onClick(DialogInterface dialog, int which) {
                          String facebookFriendName = friendsName.getText().toString();
                                String FACEBOOKID = FBID;
                               Log.i("AKO SI: ", ""+facebookFriendName + FACEBOOKID);
                       }
                    });
                    dialogBox.setNegativeButton("No", new DialogInterface.OnClickListener(){

                           public void onClick(DialogInterface dialog, int which) {

                           }
                        });
                    dialogBox.show();     

现在我在这部分遇到错误 alert_box.show();

问题是什么？

编辑根据您的建议和意见，我更改了上面的代码并在我的 Activity 上添加 getter 和 setter

private Context context;  
/////////
            public Context getContext() {
        return context;
    }

    public void setContext(Context context) {
        this.context = context;
    }

在我的activity类下绑定(bind)

    adapter2 =new LazyAdapterGetFriends(this, songsList);   
             adapter2.getContext();    
             list.setAdapter(adapter2);

但我仍然收到错误提示:

*09-11 13:48:49.298: E/AndroidRuntime(1226):    at com.fb.connect.LazyAdapterGetFriends$1.onClick(LazyAdapterGetFriends.java:95)

*pointing at AlertDialog.Builder dialogBox=new AlertDialog.Builder(context);

Answer 1

试试这个

  Button btn=(Button)vi.findViewById(R.id.btnAdd);
  btn.setOnClickListener(new OnClickListener(){

    public void onClick(View arg0) {
            // TODO Auto-generated method stub


        AlertDialog.Builder ab=new AlertDialog.Builder(MainActivity.this);
        ab.setPositiveButton("Yes", new DialogInterface.OnClickListener(){
           @Override 
           public void onClick(DialogInterface dialog, int which) {
              String facebookFriendName = friendsName.getText().toString();
                    String FACEBOOKID = FBID;
                   Log.i("AKO SI: ", ""+facebookFriendName + FACEBOOKID);
           }
        });
        ab.setNegativeButton("No", new DialogInterface.OnClickListener(){
               @Override 
               public void onClick(DialogInterface dialog, int which) {

               }
            });
        ab.show();                       
    }                
});

希望得到帮助

编辑

尝试 this.

AlertDialogs 只能使用 Activity 上下文创建，因此 getApplicationContext() 将不起作用。相反，将以下全局变量添加到您的 Activity 文件中:

Context mContext;

然后将以下内容添加到您的 onCreate() 中:

mContext = this;

现在，改变:

AlertDialog.Builder builder = new AlertDialog.Builder(getApplicationContext());

到

AlertDialog.Builder builder = new AlertDialog.Builder(mContext);