实验目的
(1)掌握Activity回传数据;
(2)android提供startActivityForResult()方法来回传数据,第一个参数是intent,第二个参数是请求码(判断数据的来源);
示例代码
//使用该方法启动Main2Activity会在MainActivity页面回调onActivityResult方法,
//所以在MainActivity页面中重写onActivityResult方法来获取返回数据
Intent intent = new Intent(this,Main2Activity.class);
startActivityForResult(intent,1);
(3)setResult()方法接收两个参数,第一个参数是结果码(0或1),第二个参数是带有数据的intent,回传过去给执行startActivityForResult()方法的Activity;
示例代码
Intent intent = new Intent();
intent.putExtra("equipment",itemInfo);//传送金剑值保存到intent
//setResult方法的作用是让当前Activity返回到它的调用者,这里是让Main2Acitivity返回到MainAcitivity
setResult(1,intent);
主要功能
实现数据的回传功能
(1)打开app主界面,显示如图:
(2)点击小宝宝购买装备,显示如图:
(3)点击这一视图任意界面,跳转为原界面,数值改变,显示如图:
程序源代码(有注释)
(1)主界面的MainActivity
package com.myapplication;
import android.content.Intent;
import android.sax.StartElementListener;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ProgressBar;
import android.widget.TextView;
import cn.itcat.domain.ItemInfo;
public class MainActivity extends AppCompatActivity {
//定义进度条
private ProgressBar mProgressBar1;
private ProgressBar mProgressBar2;
private ProgressBar mProgressBar3;
//定义属性值
private TextView mLifeTV;
private TextView mSpeedTV;
private TextView mAttackTV;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//初始化,让视图上的TextView对应到MainAcitivity
mLifeTV = (TextView)findViewById(R.id.tv_life_progress);
mSpeedTV = (TextView)findViewById(R.id.tv_speed_progress);
mAttackTV = (TextView)findViewById(R.id.tv_attack_progress);
//初始化进度条
initProgress();
}
//进度条初始化
private void initProgress(){
//初始化,让视图上的进度条对应到MainAcitivity
mProgressBar1 = (ProgressBar)findViewById(R.id.progressBar1);
mProgressBar2 = (ProgressBar)findViewById(R.id.progressBar2);
mProgressBar3 = (ProgressBar)findViewById(R.id.progressBar3);
//设置最大值
mProgressBar1.setMax(1000);
mProgressBar2.setMax(1000);
mProgressBar3.setMax(1000);
}
//开启新的activity,取得返回值
public void click(View view){
Intent intent = new Intent(this,Main2Activity.class);
//使用该方法启动Main2Activity会在MainActivity页面回调onActivityResult方法,
//所以在MainActivity页面中重写onActivityResult方法来获取返回数据
startActivityForResult(intent,1);
}
//重写onActivityResult方法如下
protected void onActivityResult(int requestCode,int resultCode,Intent data){
super.onActivityResult(requestCode,resultCode,data);
if(data!=null){
if(resultCode==1){
if(requestCode==1){
//得到在Main2Activity页面传入的值
ItemInfo info = (ItemInfo)data.getSerializableExtra("equipment");
updateProgress(info);
}
}
}
}
//更新进度条
private void updateProgress(ItemInfo info){
//得到进度条原来的值
int progress1 = mProgressBar1.getProgress();
int progress2 = mProgressBar2.getProgress();
int progress3 = mProgressBar3.getProgress();
//修改进度条的值(原来的+新增的值)
mProgressBar1.setProgress(progress1+info.getLife());
mProgressBar2.setProgress(progress2+info.getAttack());
mProgressBar3.setProgress(progress3+info.getSpeed());
//把值传给view页面
mLifeTV.setText(mProgressBar1.getProgress()+"");
mAttackTV.setText(mProgressBar2.getProgress()+"");
mSpeedTV.setText(mProgressBar3.getProgress()+"");
}
}
(2)主界面对应的xml文件
<?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"
android:orientation="vertical"
android:gravity="center"
tools:context="com.myapplication.MainActivity">
<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:layout_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_gravity="center"
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:layout_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_gravity="center"
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:layout_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:drawableRight="@android:drawable/ic_menu_add"
android:onClick="click"
android:text="小宝宝购买装备"
android:textSize="14sp"/>
</RelativeLayout>
</LinearLayout>
(3)游戏装备界面的Main2Acivit文件
package com.myapplication;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;
import cn.itcat.domain.ItemInfo;
//视图监听
public class Main2Activity extends AppCompatActivity implements View.OnClickListener {
private ItemInfo itemInfo;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);
//初始化一个武器
itemInfo = new ItemInfo("金剑",100,20,20);
//r1是视图的id,这里的意思是找到视图的id,监听视图上的click
findViewById(R.id.r1).setOnClickListener(this);
//初始化
TextView mLifeTV = (TextView)findViewById(R.id.tv_life);//tv_life是Main2Activity中的id名赋值给mLifeTV
TextView mNameTV = (TextView)findViewById(R.id.tv_name);//tv_name是Main2Activity中的id名赋值给mNameTV
TextView mSpeedTV = (TextView)findViewById(R.id.tv_speed);//tv_speed是Main2Activity中的id名赋值给mSpeedTV
TextView mAttackTV = (TextView)findViewById(R.id.tv_attack);//tv_attack是Main2Activity中的id名赋值给mAttackTV
//TextView显示字符串,传入int编译不会报错,运行会报错,
//设置金剑的属性值
mLifeTV.setText("生命值+"+itemInfo.getLife());
mNameTV.setText(itemInfo.getName()+" ");
mSpeedTV.setText("敏捷度+"+itemInfo.getSpeed());
mAttackTV.setText("攻击力+"+itemInfo.getAttack());
}
//如果这个界面上有click,触发该函数
public void onClick(View view){
switch (view.getId()){//ri位Main2Activity整个视图的属性值
case R.id.r1:
Intent intent = new Intent();
intent.putExtra("equipment",itemInfo);//传送金剑值保存到intent
//setResult方法的作用是让当前Activity返回到它的调用者,这里是让Main2Acitivity返回到MainAcitivity
setResult(1,intent);
//销毁Main2Activity
finish();
break;
}
}
}
(4)Main2Activity对应的xml文件
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
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:id="@+id/r1"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.myapplication.Main2Activity">
<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"/>
<TextView
android:id="@+id/tv_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
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:id="@+id/tv_life"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="13sp"
android:text="生命值"/>
<TextView
android:id="@+id/tv_attack"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="13sp"
android:text="攻击力"/>
<TextView
android:id="@+id/tv_speed"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="13sp"
android:text="速度"/>
</LinearLayout>
</RelativeLayout>