6.常用控件（三） 之 ProgressBar控件-handler及RadioButton

例1:

首先，让我们来看一下我们要实现的效果图，如下

具体代码实现

res下面的layout布局文件progressbar.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">


    <ProgressBar
        style="?android:attr/progressBarStyleHorizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/pb_progressbar_bar"/>

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="下载"
        android:onClick="download"
        />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/tv_progressbar_num"/>


</LinearLayout>

配置xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.zking.android06_widget3">

    <application android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">

        </activity>

        <!--写配置-->
        <activity android:name=".ProgressBarActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

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

    </application>

</manifest>

java代码

package com.zking.android06_widget3;

import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.ProgressBar;
import android.widget.TextView;

/**
 * Created by Administrator on 2017/6/7 0007.
 */

public class ProgressBarActivity extends AppCompatActivity{

        private ProgressBar pb_progressbar_bar;
        private TextView tv_progressbar_num;

       @Override
        protected void onCreate(@Nullable Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);
                setContentView(R.layout.progressbar);
                pb_progressbar_bar = (ProgressBar) findViewById(R.id.pb_progressbar_bar);
                tv_progressbar_num = (TextView) findViewById(R.id.tv_progressbar_num);
        }

       /**
        * 报错:ANR
        * application not responsing 应用程序未响应
        * why:在主线程中执行了耗时的操作
        * how:在子线程中执行耗时操作(解决方法)
        * @param view
        */
        public void download(View view){
                new MyThread().start();//一点按钮就执行
        }

        //线程间通信需要Handler
        Handler hander=new Handler(){
                //接收消息，更新UI界面
                @Override
                public void handleMessage(Message msg) {
                        super.handleMessage(msg);
                        int i= msg.what;
                        tv_progressbar_num.setText(i+"%");
                }
        };

        class MyThread extends Thread{//在子线程中执行耗时操作
               @Override
               public void run() {
                     super.run();
                     for (int i = 0; i <=100 ; i++) {//fori+回车  循环0~100
                           pb_progressbar_bar.setProgress(i);//给进度条设值
                           //在子线程中发消息
                           hander.sendEmptyMessage(i);
                           try {
                                Thread.sleep(100);//抛异常:Alt+回车
                           } catch (InterruptedException e) {
                                e.printStackTrace();
                           }
                     }
               }
        }



}


例2:
效果图:

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    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.zking.android06_widget3.MainActivity"
    android:orientation="vertical"  >

    <ImageView
            android:layout_width="380dp"
            android:layout_height="380dp"
            android:id="@+id/img_main_img1"
            />
    <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            >
            <RadioGroup
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:orientation="horizontal"
                    android:id="@+id/radio_rbs"
                    >
                    <RadioButton
                            android:layout_width="wrap_content"
                            android:layout_height="wrap_content"
                            android:text="1号佳丽"
                            android:ems="3"
                            />
                    <RadioButton
                            android:layout_width="wrap_content"
                            android:layout_height="wrap_content"
                            android:text="2号佳丽"
                            android:ems="3"
                            />
                    <RadioButton
                            android:layout_width="wrap_content"
                            android:layout_height="wrap_content"
                            android:text="3号佳丽"
                            android:ems="3"
                            />
                    <RadioButton
                            android:layout_width="wrap_content"
                            android:layout_height="wrap_content"
                            android:text="4号佳丽"
                            android:ems="3"
                            />
                    <RadioButton
                            android:layout_width="wrap_content"
                            android:layout_height="wrap_content"
                            android:text="5号佳丽"
                            android:ems="3"
                            />
                    <RadioButton
                            android:layout_width="wrap_content"
                            android:layout_height="wrap_content"
                            android:text="6号佳丽"
                            android:ems="3"
                            />
            </RadioGroup>
    </LinearLayout>


</LinearLayout>
方式一:MainActivity.java(从drawable里面获取图片)
package com.zking.android06_widget3;

import android.support.annotation.IdRes;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ImageView;
import android.widget.RadioGroup;

public class MainActivity extends AppCompatActivity {

    private ImageView img;
    private RadioGroup rbs;
    private int images[]={R.drawable.s1,
                            R.drawable.s2,
                            R.drawable.s3,
                            R.drawable.s4,
                            R.drawable.s5,
                            R.drawable.s6
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        img = (ImageView) findViewById(R.id.img_main_img1);
        rbs = (RadioGroup) findViewById(R.id.radio_rbs);

        //给ImageView设置初始图片
        img.setImageResource(images[0]);

        rbs.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(RadioGroup group, @IdRes int checkedId) {
                //切换图片
                img.setImageResource(images[checkedId]);
            }
        });
    }



}

方式二:MainActivity.java(从内存里面获取图片)
配置xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.zking.ap6">


    <!--读取内存卡的权限-->
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"></uses-permission>


    <application android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true" android:theme="@style/AppTheme">

        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

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

    </application>


</manifest>
package com.zking.ap6;

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Environment;
import android.support.annotation.IdRes;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ImageView;
import android.widget.RadioGroup;

import java.io.File;

public class MainActivity extends AppCompatActivity {

    private ImageView img;
    private RadioGroup rbs;
    File[] files;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);

            img = (ImageView) findViewById(R.id.img_main_img1);
            rbs = (RadioGroup) findViewById(R.id.radio_rbs);

            //给ImageView设置初始图片
            if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){
                String s=Environment.getExternalStorageDirectory().getAbsolutePath();
                File file=new File(s+"/images");
                files=file.listFiles();
            }
            Bitmap bm= BitmapFactory.decodeFile(files[0].getAbsolutePath());
            img.setImageBitmap(bm);
            rbs.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
                    @Override
                    public void onCheckedChanged(RadioGroup group, @IdRes int checkedId) {
                        //切换图片
                        Bitmap bm= BitmapFactory.decodeFile(files[checkedId].getAbsolutePath());
                        img.setImageBitmap(bm);
                    }
            });
    }



}