安卓中实现异步任务（4）——使用线程池实现

问题背景

上篇文章大致介绍了几种安卓汇总实现异步任务的方法，讲得比较简要，有朋友问到具体的实现方式，现在开始分列几篇文章详细介绍这几种异步的具体实现。这篇讲得是基于线程池实现，持续更新。

实现demo

（1）实现我们的线程池

import java.util.concurrent.ExecutorService;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

public class ThreadPoolUtil {
    private static int fixNum = 6;
    private static int maxNum = 8;

    private static ExecutorService fixedThreadPool = new ThreadPoolExecutor(fixNum, maxNum,
            0L, TimeUnit.MILLISECONDS, new LinkedBlockingQueue<Runnable>());;

    public static void executeRunnableByFixedPool(Runnable runnable) {
        fixedThreadPool.execute(runnable);
    }

}

（2）新建我们的activity，对应layout布局如下：

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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=".activity.HandlerThreadActivity">
    <Button
        android:id="@+id/btn1"
        android:text="启动子线程"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

</androidx.constraintlayout.widget.ConstraintLayout>

（2）对应我们activity的代码如下：

import android.os.Bundle;
import android.os.Handler;
import android.os.HandlerThread;
import android.util.Log;
import android.widget.Button;
import android.widget.TextView;

import com.alibaba.android.arouter.facade.annotation.Route;

public class HandlerThreadActivity extends AbstractSubActivity {
    private static final String TAG = "HandlerThreadActivity";
    Button button;

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

        button = findViewById(R.id.btn1);

        Thread.currentThread().setName("主线程");
        Log.d(TAG, "主线程当前线程名为" + Thread.currentThread().getId()
                + " " + Thread.currentThread().getName());

        HandlerThread handlerThread = new HandlerThread("子线程");
        handlerThread.start();
        Handler handler = new Handler(handlerThread.getLooper(), msg -> {
            if (msg.what == 1) {
                Log.d(TAG, "handlerThread当前线程名为：" + Thread.currentThread().getId()
                        + " " + Thread.currentThread().getName());
            }
            return true;
        });

        button.setOnClickListener(v -> {
            handler.sendEmptyMessage(1);

            ThreadPoolUtil.executeRunnableByFixedPool(() -> {
                Log.d(TAG, "executeRunnableByFixedPool：" + Thread.currentThread().getId()
                        + " " + Thread.currentThread().getName());
            });
        });
    }
}

执行结果如下：

关键代码分析

持续更新。。。