二、Android新建页面、页面跳转

activity_main.xml里面有一个按钮，当点击这个按钮的时候，跳转到新建的页面

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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"
    tools:context="com.example.administrator.marqueetextview.MainActivity">

    <com.example.administrator.marqueetextview.Marquee_Textview
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="我是一个Hello World!我是一个Hello World!我是一个Hello World!我是一个Hello World!"
        android:ellipsize="marquee"
        android:focusable="true"
        android:focusableInTouchMode="true"
        android:singleLine="true"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <com.example.administrator.marqueetextview.Marquee_Textview
        android:layout_marginTop="50dp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="我是一个Hello World!我是一个Hello World!我是一个Hello World!我是一个Hello World!"
        android:ellipsize="marquee"
        android:focusable="true"
        android:focusableInTouchMode="true"
        android:singleLine="true"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="我是一个textview"
        android:layout_marginTop="50dp"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent"/>
    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="页面一"/>
</android.support.constraint.ConstraintLayout>

MainActivity.java

package com.example.administrator.marqueetextview;

import android.content.Intent;
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 {
    private Button btn1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        btn1=(Button)findViewById(R.id.button1);
        btn1.setOnClickListener(new MyOnClickListener(){
            @Override
            public void onClick(View view) {
                super.onClick(view);
//                Toast.makeText(MainActivity.this,"按钮的点击事件",1).show();
                Intent intent = new Intent();
                intent.setClass(MainActivity.this,SecondPage.class);
                startActivity(intent);
            }
        });
    }
}
class MyOnClickListener implements View.OnClickListener{

    @Override
    public void onClick(View view) {

    }
}

首先建立一个secondactivity.xml文件

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:app="http://schemas.android.com/apk/res-auto">
<TextView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="这是第二个TextView"
    android:textSize="20dp"
    android:layout_marginTop="50dp"
    app:layout_constraintLeft_toLeftOf="parent"
    app:layout_constraintLeft_toRightOf="parent"
    app:layout_constraintTop_toBottomOf="parent"
    />
</android.support.constraint.ConstraintLayout>

建一个SecondPage.java

package com.example.administrator.marqueetextview;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;

/**
 * Created by Administrator on 2018/3/8 0008.
 */

public class SecondPage extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.secondactivity);

    }
}