指定Action、Category调用系统Activity实例-点击按钮，返回Home桌面

该例子，点击返回Home桌面按钮，跳转到Home桌面

activity_main.xml

<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=".MainActivity" 
    android:orientation="vertical">


    <Button android:id="@+id/backToHome"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="返回Home桌面"
        android:textSize="14dp"/>

</LinearLayout>

MainActivity.java

package com.example.backtohome;

import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class MainActivity extends Activity {

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

Button but=(Button) super.findViewById(R.id.backToHome);
but.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
Intent intent=new Intent();
intent.setAction(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_HOME);
startActivity(intent);
}
});
}
}