Android 线程和处理程序没有停止

Question

我在 android 中尝试了简单的代码，它每秒将 textView 更改为经过的秒数：

onCreate 方法：

        Runnable runnable = new Wait(15);

        sleep = new Thread(runnable);

        sleep.start();

一个扩展 Thread 的新类：

    class Wait extends Thread {
        int seconds;

        Wait(int seconds) {
            this.seconds = seconds;
        }

        @Override
        public void run() {
            for (int i = 1 ; i < this.seconds + 1; i++) {
                try {
                    Thread.sleep(1000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }

                int finalI = i;
                handler.post(new Runnable() {
                    @Override
                    public void run() {
                        textView.setText(finalI + "");
                    }
                });
            }
        }
    }

我正在尝试（没有任何成功）阻止它：

        // onClick button method
        sleep.interrupt();

为什么它不起作用？ 它不会停止线程。它只是缩短了睡眠时间。之后，文本保持更改（循环继续运行）。

Answer 1

打电话给

sleep.interrupt();

不要停止它just set thread's interrupt status and if this thread is blocked for example by Thread.sleep() then its interrupt status will be cleared and it will receive an InterruptedException. 的线程（关注链接以查看更多 deales）。

这就是为什么您每次都应该检查Thread.isInterrupted() 并在获得catch 块时完成run() 方法执行（例如，通过调用return）获得InterruptedException 或创建您自己的标志来照亮线程中断.

您可以像这样更改您的代码：

        @Override
        public void run() {
            for (int i = 1 ; i < (this.seconds + 1) && !isInterrupted(); i++) {
                try {
                    Thread.sleep(1000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                    return;
                }

                int finalI = i;
                handler.post(new Runnable() {
                    @Override
                    public void run() {
                        textView.setText(finalI + "");
                    }
                });
            }
        }

或者用你自己的旗帜：

class Wait extends Thread {
    int seconds;

    private volatile boolean iInterruptThisThread = false;

    Wait(int seconds) {
        this.seconds = seconds;
    }
    
    public void interruptThreadMySelf() {
        iInterruptThisThread = true;
        super.interrupt();
    }

    @Override
    public void run() {
        for (int i = 1; i < (this.seconds + 1) && !iInterruptThisThread; i++) {
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
                if(iInterruptThisThread) {
                    return;
                }
            }

            int finalI = i;
            handler.post(new Runnable() {
                @Override
                public void run() {
                    textView.setText(finalI + "");
                }
            });
        }
    }
}
class Wait extends Thread {
    int seconds;

    private volatile boolean iInterruptThisThread = false;

    Wait(int seconds) {
        this.seconds = seconds;
    }
    
    public void interruptThreadMySelf() {
        iInterruptThisThread = true;
        super.interrupt();
    }

    @Override
    public void run() {
        for (int i = 1; i < (this.seconds + 1) && !iInterruptThisThread; i++) {
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
                if(iInterruptThisThread) {
                    return;
                }
            }

            int finalI = i;
            handler.post(new Runnable() {
                @Override
                public void run() {
                    textView.setText(finalI + "");
                }
            });
        }
    }
}

然后拨打sleep.interruptThreadMySelf()

顺便说一句，您可以使用sleep = new Wait(15); 而不是sleep = new Thread(runnable);。