Android关于PopupMenu第一个参数使用this报错，具体如下

Question

lv1.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener(){
 @Override
 public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) { 
if (id > 0) {
 popup = new PopupMenu(this, view);//这里用this会报错
 popup.getMenuInflater().inflate(R.menu.simple_menu1, popup.getMenu());
 popup.show(); 
popup.setOnMenuItemClickListener(new PopupMenu.OnMenuItemClickListener() {
 @Override 
public boolean onMenuItemClick(MenuItem item) { 
switch (item.getItemId()) {
 case R.id.menu1: ArrayAdapter temp_adp = (ArrayAdapter) lv1.getAdapter(); 
temp_adp.remove(temp_adp.getItem(selected_position)); 
return true; 
default: return false;
 }
 }
 });
 } 
return true;
 }
 });

Answer 1

使用 XXXActivity.this 就行了。
你的这个 this 是指向了 OnItemLongClickListener 的匿名内部类了，所以会报错

Answer 2

package com.example.administrator.listviewexp;import android.app.Activity;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.AdapterView;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.EditText;
import android.widget.Button;
import android.widget.PopupMenu;
import android.view.MenuItem;
import android.content.Context;
import android.widget.SimpleAdapter;public class MainActivity extends AppCompatActivity {    public Button bt1;
    public ListView lv1;
    private int selected_position = -1;
    private PopupMenu popup;    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);        bt1.setOnClickListener(new View.OnClickListener(){
            @Override
            public void onClick(View v)
            {
                EditText et_c,et_a,et_n;
                et_c=(EditText)findViewById(R.id.et_c);
                et_a=(EditText)findViewById(R.id.et_a);
                et_n=(EditText)findViewById(R.id.et_n);
                ArrayAdapter temp_adp=(ArrayAdapter) lv1.getAdapter();
                temp_adp.add(et_c.getText().toString()+"   "+et_a.getText().toString()+"     "+et_n.getText().toString());
            }
        });
        lv1.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener(){
            @Override
            public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
                if (id > 0)
                {
                    popup = new PopupMenu(getActivity(), view);
                    popup.getMenuInflater().inflate(R.menu.simple_menu1, popup.getMenu());
                    popup.show();
                    popup.setOnMenuItemClickListener(new PopupMenu.OnMenuItemClickListener() {
                        @Override
                        public boolean onMenuItemClick(MenuItem item) {
                            switch (item.getItemId()) {
                                case R.id.menu1:
                                ArrayAdapter temp_adp = (ArrayAdapter) lv1.getAdapter();
                                    temp_adp.remove(temp_adp.getItem(selected_position));
                                    return true;
                                default:
                                    return false;
                            }
                        }
                    });
                }
        return true;
        }
        });
    }
}代码全贴上了，我好像没有XXXActivity之类的

Answer 3

就是 MainActivity.this ，这样指向的就是当前的 Activity 对象了，之前贴的代码看不到类名，所以写的 XXXActivity 

Answer 4

 popup = new PopupMenu(getActivity(), view); 改成 popup = new PopupMenu(MainActivity.this, view);