是否有可能調用從UI線程Thread類的網絡的方法？

Question

我很好奇它是否有可能從UI線程調用網絡的過程，如果調用的方法是在一個線程類...僞的實例...

class MyNetworkClass extends Thread{ 
    public boolean keepGoing = true; 
    public void run(){ 
     while(keepGoing); 
    } 

    public void doSomeNetworkStuff(){ 
     //do things that are illegal on the UI Thread 
    } 

} 

//and then in my Activity... 
MyNetworkClass mnc = new MyNetworkClass(); 
mnc.start(); 

mnc.doSomeNetworkStuff(); 

這種感覺完全是非法的對我來說，但我想知道這是否是事實，如果是的話，爲什麼？

Answer 1

你居然叫從同一個線程mnc.start();的mnc.doSomeNetworkStuff()方法。 這大概是UI線程，但肯定不是剛剛開始mnc.start線程;

審時度勢：

//creates thread object - does not start a new thread yet 
Thread thread = new Thread() { 
    public void run() {} 
}; 
//... 

thread.start(); //this actually started the thread 
// the `run` method is now executed in this thread. 

//However if you called `run` manually as below 
thread.run(); 
// it would be executed in the thread from which you have called it 
// assuming that this flow is running in the UI thread, calling `thread.run()` 
// manually as above makes it execute in the UI thread. 

編輯：

只是爲了讓事情更加清楚。想想看，你有一些靜態工具類象下面這樣：

public static class SomeUtilityClass { 

    public static void someUtilityMethod(int i) { 
     Log.i("SomeUtilityClass", "someUtilityMethod: " + i); 
    } 
} 

然後地方在你的代碼，請從「主」線程調用：

new Thread() { 

    @Override 
    public void run() { 
     // 1. 
     // call the utility method in new thread 
     SomeUtilityClass.someUtilityMethod(1); 
    } 
}.start(); 

// 2. 
// call the same method from "main" thread 
SomeUtilityClass.someUtilityMethod(2); 

注意Thread#start()立即退出，你都不能保證其致電SomeUtilityClass.someUtilityMethod();將首先執行。