单击按钮时如何打印消息

本文介绍了单击按钮时如何打印消息的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

package com.example.button; import android.support.v7.app.AppCompatActivity; import android.os。捆绑; 导入android.view.View; 导入android.widget.Button; 导入android.widget.Toast; 公共类MainActivity扩展AppCompatActivity { 按钮按钮; @Override protected void onCreate（Bundle savedInstanceState）{ super.onCreate（savedInstanceState）; setContentView（R.layout.activity_main）; button =（Button）findViewById（R.id.button）; } @Override protected void onClick（查看视图） {b button.setOnClickListener（new View.OnClickListener（））; Toast t = Toast.makeText（MainActivity.this，U HAV e点击我，Toast.LENGTH_LONG）; t.show（）; } } 我写了这段代码，这样当我按按钮我的外出将是-U已经点击了我 我尝试了什么： package com.example.button; import android.support.v7.app.AppCompatActivity; import android.os .Bundle; 导入android.view.View; 导入android.widget.Button; 导入android.widget.Toast; 公共类MainActivity扩展AppCompatActivity { 按钮按钮; @Override protected void onCreate（Bundle savedInstanceState）{ super.onCreate（savedInstanceState）; setContentView（R.layout.activity_main）; button =（Button）fin dViewById（R.id.button）; } @Override protected void onClick（查看视图）{ button.setOnClickListener（new View.OnClickListener（））; Toast t = Toast.makeText（MainActivity.this，U Have Clicked Me，Toast.LENGTH_LONG）; t.show（）; } }

package com.example.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 { Button button; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); button = (Button) findViewById(R.id.button); } @Override protected void onClick(View view) { button.setOnClickListener(new View.OnClickListener()); Toast t = Toast.makeText(MainActivity.this, "U Have Clicked Me", Toast.LENGTH_LONG); t.show(); } } I wrote this code so that when i press the button my outout will be-U Have Clicked Me What I have tried: package com.example.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 { Button button; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); button = (Button) findViewById(R.id.button); } @Override protected void onClick(View view) { button.setOnClickListener(new View.OnClickListener()); Toast t = Toast.makeText(MainActivity.this, "U Have Clicked Me", Toast.LENGTH_LONG); t.show(); } }

推荐答案

您错过了将 setOnClickListener 设置为按钮。 You missed to set setOnClickListener to button. public class MainActivity extends AppCompatActivity implements View.OnClickListener{ Button button; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); button = (Button) findViewById(R.id.button); button.setOnClickListener(this); // add this line } @Override protected void onClick(View view) { Toast t = Toast.makeText(MainActivity.this, "U Have Clicked Me",Toast.LENGTH_LONG); t.show(); } }

此外，请格式化您的代码，使其更具可读性。

And also, please format your code nicely so it more readable.