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