实现直播带货系统开发通知栏显示下载图片的进度条

直播带货系统开发实现通知栏显示下载图片的进度条具体代码如下：

<?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: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.acer_pc.progresscontent.MainActivity">
 
    <Button
        android:id="@+id/btn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="点击下载" />
    <ImageView
        android:id="@+id/iview"
        android:layout_below="@id/btn"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:src="@mipmap/ic_launcher"/>
</RelativeLayout>

在activity中我已经添加了详细的注解，代码如下：

package com.example.acer_pc.progresscontent;
 
import android.app.Notification;
import android.app.NotificationManager;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
 
import com.squareup.okhttp.Call;
import com.squareup.okhttp.Callback;
import com.squareup.okhttp.OkHttpClient;
import com.squareup.okhttp.Request;
import com.squareup.okhttp.Response;
import com.squareup.okhttp.ResponseBody;
 
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
 
public class MainActivity extends AppCompatActivity {
    //图片的下载路径
    private String path = "http://p3.so.qhmsg.com/t016f0540122dbc10c3.jpg";
    private Handler handler = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            super.handleMessage(msg);
            Bitmap bitmap = (Bitmap) msg.obj;
            //让进度条加载完成后自动消失
            manager.cancel(3);
            //为imageview设置图片资源
            imageView.setImageBitmap(bitmap);
 
        }
    };
    private Button button;
    private ImageView imageView;
    private NotificationManager manager;
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //查找控件
        button = (Button) findViewById(R.id.btn);
        imageView = (ImageView) findViewById(R.id.iview);
        //创建notify管理者对象
        manager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
        //button按钮的点击事件，当点击button按钮的时候进行进度条的显示，并下载图片
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //调用方法
                init();
            }
        });
    }
 
    private void init() {
        //创建notification builder 对象
        final Notification.Builder mbuilder = new Notification.Builder(this);
        //设置通知栏图标
        mbuilder.setSmallIcon(android.R.mipmap.sym_def_app_icon);
        //设置通知栏提示语
        mbuilder.setContentText("正在下载");
 
 
        //创建OkHttpClient对象
        OkHttpClient client = new OkHttpClient();
        //创建请求对象的建造者
        final Request.Builder builder = new Request.Builder();
        //添加下载路径
        builder.url(path);
        //通过建造者对象，创建请求对象
        Request request = builder.build();
        //创建call对象
        Call call = client.newCall(request);
        call.enqueue(new Callback() {
            @Override
            //请求失败时调用的方法
            public void onFailure(Request request, IOException e) {
 
            }
 
            @Override
            //请求响应成功时调用的方法
            public void onResponse(Response response) throws IOException {
                //创建一个变量记录下载了的总的大小
                int download = 0;
                //获取响应对象
                ResponseBody body = response.body();
                //获取网络请求的最大值
                int length = (int) body.contentLength();
                //获取数据流
                InputStream inputStream = body.byteStream();
                //创建一个字节数组输出流
                ByteArrayOutputStream bos = new ByteArrayOutputStream();
 
                int len = 0;
                byte[] bytes = new byte[1024];
                while ((len = inputStream.read(bytes)) != -1) {
                    download += len;
                    mbuilder.setProgress(100, ((int) download / length * 100), false);
                    manager.notify(3, mbuilder.build());
                    bos.write(bytes, 0, bytes.length);
                    bos.flush();
 
                }
                //将字节数组输出流转换成bitmap对象
                byte[] bytes1 = bos.toByteArray();
                Bitmap bitmap = BitmapFactory.decodeByteArray(bytes1, 0, bytes1.length);
                if (bitmap != null) {
                    Message message = handler.obtainMessage();
                    message.obj = bitmap;
                    handler.sendMessage(message);
                }
 
            }
        });
 
    }
 
}

以上就是 直播带货系统开发实现通知栏显示下载图片的进度条，更多内容欢迎关注之后的文章