3.11

所花时间：1小时

代码量：47

博客篇：1

了解到的知识点

package com.example.myapplication;

import static com.example.myapplication.R.*;
import static com.example.myapplication.R.id.button3;

import android.annotation.SuppressLint;
import android.os.Bundle;
import android.os.Handler;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import androidx.activity.EdgeToEdge;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.graphics.Insets;
import androidx.core.view.ViewCompat;
import androidx.core.view.WindowInsetsCompat;

import java.security.AccessController;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {
    private TextView result;
    private Button button3;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(layout.activity_main);
        result = findViewById(id.result);
        button3 = findViewById(id.button3);
        button3.setOnClickListener(new MyOnClickListener());
    }

    class MyOnClickListener implements View.OnClickListener{

        @Override
        public void onClick(View v) {
            result.setText("yes");
        }
    }

　　设置button3的点击事件

先findViewById

再setOnClickListener
再重写onClick