Android实现进度条（ProgressBar）的功能与用法

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package com.example.test03;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.widget.ProgressBar;

import java.lang.ref.WeakReference;

public class Main5Activity extends AppCompatActivity {
//  该模拟填充长度为100的数组
  private int[] data=new int[100];
  private int hasdata=0;
//  记录ProgressBar的完成进度
  int status=0;
  private ProgressBar bar;
  private ProgressBar bar2;
  static class MyHandler extends Handler{
    private WeakReference activity;
    MyHandler(WeakReference activity){
      this.activity=activity;
    }

    @Override
    public void handleMessage(@NonNull Message msg) {
//      表明该消息是该程序发送的
      if (msg.what==0x111){
        activity.get().bar.setProgress(activity.get().status);
        activity.get().bar2.setProgress(activity.get().status);
      }
    }
  }
//  负责更新进度
  MyHandler myHandler=new MyHandler(new WeakReference<>(this));
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main5);
    bar=findViewById(R.id.bar);
    bar2=findViewById(R.id.bar2);
//    启动线程在执行进度
    new Thread(){
      @Override
      public void run() {
        while (status<100){
//          获取耗时操作的完成百分比
          status=doWork();
//          发送消息
          myHandler.sendEmptyMessage(0x111);
        }
      }
    }.start();
  }
//  模拟耗时操作
  public int doWork() {
//    为数组元素赋值
    data[hasdata++] = (int) (Math.random() * 100);
    try {
      Thread.sleep(1000);
    } catch (InterruptedException e) {
      e.printStackTrace();
    }
    return hasdata;
  }
}