当存在做个Button时，就可以通过重写 onClick 方法实现Button点击事件的封装，便于管理。

package com.example.love.button;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity implements View.OnClickListener{
    private View view;
    private Button button1;
    private  Button button2;
    private  Button button3;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        view = (View) this.findViewById(R.id.relativeLayout);
//        view.setOnClickListener(new View.OnClickListener() {
//            @Override
//            public void onClick(View v) {
//                Toast.makeText(MainActivity.this, "Click me!!!!", Toast.LENGTH_LONG).show();
//            }
//        });

        button1 = (Button) this.findViewById(R.id.button1);
        button2 = (Button) this.findViewById(R.id.button2);
        button3 = (Button) this.findViewById(R.id.button3);

        button1.setOnClickListener(this);
        button2.setOnClickListener(this);
        button3.setOnClickListener(this);
//        button1.setOnClickListener(new View.OnClickListener() {
//            @Override
//            public void onClick(View v) {
//                Toast.makeText(MainActivity.this, "点击按钮Button", Toast.LENGTH_LONG).show();
//            }
//        });
//        // OnLongClickListener包含OnClickListener事件
//        // 所以在OnLongClickListener中处理了，就不要在 OnClickListener 中处理了
//        button1.setOnLongClickListener(new View.OnLongClickListener() {
//            @Override
//            public boolean onLongClick(View v) {
//                Toast.makeText(MainActivity.this, "长按点击按钮Button", Toast.LENGTH_LONG).show();
//                return false;
//            }
//        });
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()){
            case R.id.button1:
                Toast.makeText(MainActivity.this, "Click me!!!!", Toast.LENGTH_SHORT).show();
                break;
            case R.id.button2:
                Toast.makeText(MainActivity.this, "Click me!!!!", Toast.LENGTH_SHORT).show();
                break;
            case R.id.button3:
                Toast.makeText(MainActivity.this, "Click me!!!!", Toast.LENGTH_SHORT).show();
                break;
        }
    }
}