AndroidStudio实现进度条效果

<&＃63;xml version="1.0" encoding="utf-8"&＃63;>


    
    

package com.example.a18101352;

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.util.Random;

public class MainActivity extends AppCompatActivity {


    private ProgressBar progressBar;
    private int maxProgress;
    private int currentProgress = 0;

    private Handler mHandler = new Handler(){
        /**
         * Subclasses must implement this to receive messages.
         *
         * @param msg
         */
        @Override
        public void handleMessage(@NonNull Message msg) {
            super.handleMessage(msg);
            switch (msg.what){
                case 0:
                    progressBar.setProgress(currentProgress);
                    break;
            }
        }
    };


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_progress_bar);
        progressBar = findViewById(R.id.pb_determinate);
        maxProgress = progressBar.getMax();
    }

    @Override
    protected void onStart(){
        super.onStart();
        new Thread() {

            private Random random;

            @Override
            public void run(){
                while(true){
                    try {
                        for(int i = 0; i  maxProgress){
//                                break;
//                            }
                            //获取一个随机数给到currentProgress然后显示出来
                            currentProgress = random.nextInt(100);
                            mHandler.sendEmptyMessage(0);
                        }
                    }
                    catch (InterruptedException e){
                        e.printStackTrace();
                    }
                }
            }
        }.start();
    }
}