安卓入门小程序

1.mainactivity

package com.example.pro.first;

import android.support.v7.app.AppCompatActivity;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.LinearLayout;

public class Main2Activity extends Activity {

    int[] images = new int[]{
            R.drawable.a1,
            R.drawable.a2,
            //res／drawable文件夹下面图片的名字  教程上应该是下面的代码 但是报错

   /*         R.drawable.swift,
            R.drawable.ajax,
            R.drawable.html,
*/
    };
    int currentImg = 0 ;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);
        LinearLayout main = (LinearLayout) findViewById(R.id.linerlayout);
        final ImageView image = new ImageView(this);
        main.addView(image);
        image.setImageResource(images[0]);
        image.setOnClickListener(new View.OnClickListener(){
            @Override
                    public void onClick(View v)
            {
                image.setImageResource(images[++currentImg % images.length]);
            }
        });

    }


}

　　2.activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_main2"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.pro.first.Main2Activity">

    <LinearLayout
        android:orientation="vertical"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_alignParentTop="true"
        android:id="@+id/linerlayout"></LinearLayout>
</RelativeLayout>

　　运行界面如下 图片是自己放在 res／drawable文件夹下面的图片