android基础知识清单。

Android中给button注册事件的四种方法 

https://blog.csdn.net/qq_45064049/article/details/90383158

 

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".ButtonActivity"
    android:orientation="vertical">

    <Button
        android:id="@+id/btn1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="通过自定义内部类实现点击事件"/>

    <Button
        android:id="@+id/btn2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="通过匿名内部类实现点击事件"/>

    <Button
        android:id="@+id/btn3"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="通过当前Activity去实现点击事件接口"/>

    <Button
        android:id="@+id/btn4"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="在xml文件中绑定"
        android:onClick="myClick"/>

    <Button
        android:id="@+id/btn5"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="在xml文件中绑定2"
        android:onClick="myClick"/>
</LinearLayout>

package com.example.uidemo;

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

public class ButtonActivity extends AppCompatActivity implements View.OnClickListener{

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_button);

        //1.获取按钮
        Button btn1 = findViewById(R.id.btn1);
        //点击事件：被点击时被触发的事件
        MyClickListener mcl = new MyClickListener();
        btn1.setOnClickListener(mcl);       //2.为按钮注册点击事件监听器

        //匿名内部类适用于有唯一操作的按钮
        Button btn2 = findViewById(R.id.btn2);
        btn2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                //在控制台输出
                Log.e("TAG","==========匿名内部类==========");

　　　　　　　　　Toast.makeText(MainActivity.this,
                         "按钮被点击", Toast.LENGTH_SHORT).show();

            }
        });

        Button btn3 = findViewById(R.id.btn3);
        btn3.setOnClickListener(this);
}

    @Override
    public void onClick(View view) {
        Log.e("TAG","用本类实现了OnClickListener");
    }

    class MyClickListener implements View.OnClickListener{

        @Override
        public void onClick(View view) {
            //在控制台输出一条语句
            Log.e("TAG","刚刚点击的按钮时注册了内部类监听器对象的按钮");
        }
    }

    //参数：被点击的控件对象
    public void myClick(View v){
        switch (v.getId()){
            case R.id.btn4:
                Log.e("TAG","btn4======");
                break;
            case R.id.btn5:
                Log.e("TAG","btn5======");
                break;

        }
    }
}

页面跳转。

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
          package="com.imooc.demo">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity"
            android:label="main">
        </activity>

        <activity android:name=".TestActivity"
                  android:launchMode="singleTop"
            android:label="testActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>

                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>

        <activity android:name=".NewActivity"
            android:label="newActivity"></activity>
    </application>

</manifest>

package com.imooc.demo;

import android.content.Intent;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;

/**
 * Created by renkangke .
 */
public class NewActivity extends AppCompatActivity {

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_new);
        Button newButton = findViewById(R.id.newButton);
        newButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent(NewActivity.this, TestActivity.class);
                startActivity(intent);
            }
        });

    }
}

package com.imooc.demo;

import android.content.Intent;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

/**
 * Created by renkangke .
 */
public class TestActivity extends AppCompatActivity{

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        // activity与layout进行了关联
        setContentView(R.layout.activity_test);

        // 通过findViewById将layout中的控件找出来，并转化成View
        final TextView textView = findViewById(R.id.titleTextView);
        // 打到button这个view
        Button button = findViewById(R.id.button);

        // 设置点击事件
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // 为textView动态设置文本
                textView.setText(getString(R.string.app_name));

                // 跳转到一个NewActivity
                Intent intent = new Intent(TestActivity.this, TestActivity.class);
                startActivity(intent);

            }
        });


    }
}