Android案例—装备选择

1.运用知识

1.组件ProgressBar的使用

2.startActivityForResult方法的使用

2.实验仪器

装有Android开发环境的计算机

3.实验要求

实现通过购买装备增加生命值的功能

4.实验环境

1.创建程序

新建项目，然后在activity_main.xml中编写如下代码：

xml version="1.0" encoding="utf-8"?>
<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"
    android:gravity="center">
<ImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/pet_imgv"
    android:layout_gravity="center_horizontal"
    android:layout_margin="5dp"
    android:layout_marginTop="30dp"
    android:src="@drawable/baby"
    />
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/pet_dialog_tv"
        android:layout_gravity="center_horizontal"
        android:gravity="center"
        android:text="主人快给小宝宝购买装备吧"/>
    <TableLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_marginBottom="20dp">
        <TableRow
            android:layout_width="fill_parent"
            android:layout_height="wrap_content">
            <TextView
                android:layout_width="0dip"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="生命值："
                android:textColor="@android:color/black"
                android:textSize="14sp"/>

            <ProgressBar
                android:id="@+id/progressBar1"
                style="?android:attr/progressBarStyleHorizontal"
                android:layout_width="0dip"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:layout_weight="2"/>
            <TextView
                android:id="@+id/tv_life_progress"
                android:layout_width="0dip"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="0"
                android:gravity="center"
                android:textColor="#000000"/>
        TableRow>
        <TableRow
            android:layout_width="fill_parent"
            android:layout_height="wrap_content">
            <TextView
                android:layout_width="0dip"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="攻击力："
                android:textColor="@android:color/black"
                android:textSize="14sp"/>

            <ProgressBar
                android:id="@+id/progressBar2"
                style="?android:attr/progressBarStyleHorizontal"
                android:layout_width="0dip"
                android:layout_height="wrap_content"
                android:layout_weight="2"/>
            <TextView
                android:id="@+id/tv_attack_progress"
                android:layout_width="0dip"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="0"
                android:gravity="center"
                android:textColor="#000000"/>
        TableRow>
        <TableRow
            android:layout_width="fill_parent"
            android:layout_height="wrap_content">
            <TextView
                android:layout_width="0dip"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="敏捷："
                android:textColor="@android:color/black"
                android:textSize="14sp"/>

            <ProgressBar
                android:id="@+id/progressBar3"
                style="?android:attr/progressBarStyleHorizontal"
                android:layout_width="0dip"
                android:layout_height="wrap_content"
                android:layout_weight="2"/>
            <TextView
                android:id="@+id/tv_speed_progress"
                android:layout_width="0dip"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="0"
                android:gravity="center"
                android:textColor="#000000"/>
        TableRow>
    TableLayout>

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginLeft="50dp"
        android:layout_marginRight="50dp"
        android:layout_marginTop="20dp"
        >
        <Button
            android:id="@+id/btn_baby"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:drawablePadding="3dp"
            android:drawableLeft="@android:drawable/ic_menu_add"
            android:onClick="click"
            android:text="小宝宝购买装备"
            android:textSize="14sp"
            android:gravity="center"
            android:background="@android:color/darker_gray"
             />
    RelativeLayout>
LinearLayout>

2.创建装备界面

创建装备界面activity_shop.xml，然后在activity_shop.xml中编写如下代码：

xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/rl"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    >
    <View
        android:layout_width="30dp"
        android:layout_height="30dp"
        android:background="@android:drawable/ic_menu_info_details"
        android:layout_centerVertical="true"
        android:layout_alignParentLeft="true"
        >View>
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/tv_name"
        android:layout_centerVertical="true"
        android:layout_marginLeft="60dp"
        android:text="商品名称"/>
    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:orientation="vertical">
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:id="@+id/tv_life"
            android:textSize="13sp"
            android:text="生命值"/>
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:id="@+id/tv_attack"
            android:textSize="13sp"
            android:text="攻击力"/>
        <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/tv_speed"
        android:textSize="13sp"
        android:text="速度"/>
    LinearLayout>

RelativeLayout>

该界面是用来展示装备的，界面编写完成后，运行效果如图所示：

3.创建ItemInfo类

在程序中创建一个cn.itcast.domain包，在该包中创建一个ItemInfo类，用于封装装备信息。具体代码如下:

public class ItemInfo implements Serializable {
    private String name;
    private int attack;
    private int life;
    private int speed;
    public ItemInfo (String name,int attack,int life,int speed){
        this.name=name;
        this.attack=attack;
        this.life=life;
        this.speed=speed;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAttack() {
        return attack;
    }

    public void setAttack(int attack) {
        this.attack = attack;
    }

    public int getLife() {
        return life;
    }

    public void setLife(int life) {
        this.life = life;
    }

    public int getSpeed() {
        return speed;
    }

    public void setSpeed(int speed) {
        this.speed = speed;
    }
    public String toString(){
        return "[name="+name+",attack="+attack+",life="+life+",speed="+speed+"]";
    }

4.创建ShoActivity

ShopActivity是用来展示装备信息的，当单击ShopActivity的装备时，会调用MainActivity并将信息回传给MainActivity。ShopActivity的具体代码如下所示：

public class ShopActivity extends Activity implements View.OnClickListener {
    private ItemInfo itemInfo;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_shop);
        itemInfo=new ItemInfo("金剑",100,20,20);
        findViewById(R.id.rl).setOnClickListener(this);
        TextView  mLifeTV=(TextView)findViewById(R.id.tv_life);
        TextView  mNameTV=(TextView)findViewById(R.id.tv_name);
        TextView  mAttackTV=(TextView)findViewById(R.id.tv_attack);
        TextView  mSpeedTV=(TextView)findViewById(R.id.tv_speed);
        mLifeTV.setText("生命值+"+itemInfo.getLife());
        mNameTV.setText(itemInfo.getName());
        mSpeedTV.setText("敏锐度+"+itemInfo.getSpeed());
        mAttackTV.setText("攻击力+"+itemInfo.getAttack());
    }
    public void onClick(View v){
        switch(v.getId()){
            case R.id.rl:
                Intent intent=new Intent();
                intent.putExtra("equipment",itemInfo);
                setResult(1,intent);
                finish();
                break;

        }
    }

5.编写界面交互代码（MainActivity）

接下来编写MainActivity.MainActivity主要用于相应按钮的点击事件，并将返回的装备信息显示在指定的ListView控件中，具体代码如下：

public class MainActivity extends Activity {
    private ProgressBar mProgressBar1;
    private ProgressBar mProgressBar2;
    private ProgressBar mProgressBar3;
    private TextView mLifeTV;
    private TextView mAttackTV;
    private TextView mSpeedTV;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mLifeTV=(TextView)findViewById(R.id.tv_life_progress);
        mAttackTV=(TextView)findViewById(R.id.tv_attack_progress);
        mSpeedTV=(TextView)findViewById(R.id.tv_speed_progress);
        initProgress();
    }
    private void initProgress() {
        mProgressBar1=(ProgressBar)findViewById(R.id.progressBar1);
        mProgressBar2=(ProgressBar)findViewById(R.id.progressBar2);
        mProgressBar3=(ProgressBar)findViewById(R.id.progressBar3);
        mProgressBar1.setMax(1000);
        mProgressBar2.setMax(1000);
        mProgressBar3.setMax(1000);
    }
    public void click(View view){
        Intent intent=new Intent(this,ShopActivity.class);
        startActivityForResult(intent,1);
    }
    protected void onActivityResult(int requestCode,int resultCode,Intent data){
        super.onActivityResult(requestCode,resultCode,data);
        if(data!=null) {
            if (resultCode == 1) {
                if (requestCode == 1) {
                    ItemInfo info=(ItemInfo)data.getSerializableExtra("equipment");
                    updateProgress(info);
                }
            }
        }
    }

    private void updateProgress(ItemInfo info) {
        int progress1=mProgressBar1.getProgress();
        int progress2=mProgressBar2.getProgress();
        int progress3=mProgressBar3.getProgress();
        mProgressBar1.setProgress(progress1+info.getLife());
        mProgressBar2.setProgress(progress2+info.getAttack());
        mProgressBar3.setProgress(progress3+info.getSpeed());
        mLifeTV.setText(mProgressBar1.getProgress()+"");
        mAttackTV.setText(mProgressBar2.getProgress()+"");
        mSpeedTV.setText(mProgressBar3.getProgress()+"");
    }

}

6.清单配置文件

使用Activity时需要在清单文件中配置，具体代码如下：

xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.administrator.equipment">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@string/app_name">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            intent-filter>
        activity>
        <activity android:name=".ShopActivity">activity>
    application>

manifest>

7.运行程序选择装备