<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="sample.android_serialport_api.myapplication.MainActivity">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hello World!"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="bt1"
android:id="@+id/butto1"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="bt2"
android:id="@+id/butto2"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="bt3"
android:id="@+id/butto3"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="bt4"
android:id="@+id/butto4"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="bt5"
android:id="@+id/butto5"/>
</LinearLayout>
package sample.android_serialport_api.myapplication;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
public class MainActivity extends AppCompatActivity implements View.OnClickListener{
Button bt1 = null;
Button bt2 = null;
Button bt3 = null;
Button bt4 = null;
Button bt5 = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
bt1 = (Button) findViewById(R.id.butto1);
bt2 = (Button) findViewById(R.id.butto2);
bt3 = (Button) findViewById(R.id.butto3);
bt4 = (Button) findViewById(R.id.butto4);
bt5 = (Button) findViewById(R.id.butto5);
//方法1:匿名内部类
bt1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
System.out.println("方式1:按键1");
}
});
bt2.setOnClickListener(new Bt2Listener());
bt3.setOnClickListener(this);
bt4.setOnClickListener(this);
bt5.setOnClickListener(this);
}
//方法2:内部类继承View.OnClickListener
private class Bt2Listener implements View.OnClickListener{
public void onClick(View v) {
System.out.println("方式2:按键2");
}
}
//方法3:activity继承View.OnClickListener
public void onClick(View v) {
System.out.print("方式3:");
int i = v.getId();
switch(i){
case R.id.butto3:
System.out.println("按键3");
break;
case R.id.butto4:
System.out.println("按键4");
break;
case R.id.butto5:
System.out.println("按键5");
break;
default:break;
}
}
}