创建第二个activity并启动

1）com.example.helloworld路径下创建SecondActivity.java文件：

package com.example.helloworld;

import android.app.Activity;

import android.os.Bundle;

public class SecondActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_second_layout);
}

}

2）必要的地方使用Intent启动activity

Intent intent = new Intent(HelloWorldActivity.this, SecondActivity.class);

startActivity(intent);