在线程和Runnable接口的Android更新的TextView [英] Android update TextView in Thread and Runnable
问题描述
我想在Android的一个简单的定时器,更新一个TextView每一秒。它只是简单地计算秒像扫雷。
I want to make a simple timer in Android that updates a TextView every second. It simply counts seconds like in Minesweeper.
现在的问题是,当我忽略tvTime.setText(...)(使它//tvTime.setText(...),在LogCat中会打印以下数量的每一秒。 但是,当我想这个数字设置为一个TextView(在另一个线程创建的),该程序崩溃。
The problem is when i ignore the tvTime.setText(...) (make it //tvTime.setText(...), in LogCat will be printed the following number every second. But when i want to set this number to a TextView (created in another Thread), the program crashes.
有没有人有一个想法如何轻松解决呢?
Does anyone have an idea how to solve this easily?
这里的code(方法称为启动):
Here's the code (method is called on startup):
private void startTimerThread() {
Thread th = new Thread(new Runnable() {
private long startTime = System.currentTimeMillis();
public void run() {
while (gameState == GameState.Playing) {
System.out.println((System.currentTimeMillis() - this.startTime) / 1000);
tvTime.setText("" + ((System.currentTimeMillis() - this.startTime) / 1000));
try {
Thread.sleep(1000);
}
catch (InterruptedException e) {
e.printStackTrace();
}
}
}
});
th.start();
}
编辑:
最后,我得到了它。 这里是解决方案,对于那些谁感兴趣的
Finally, I got it. Here is the solution, for those who are interested in.
private void startTimerThread() {
Thread th = new Thread(new Runnable() {
private long startTime = System.currentTimeMillis();
public void run() {
while (gameState == GameState.Playing) {
runOnUiThread(new Runnable() {
@Override
public void run() {
tvTime.setText(""+((System.currentTimeMillis()-startTime)/1000));
}
});
try {
Thread.sleep(1000);
}
catch (InterruptedException e) {
e.printStackTrace();
}
}
}
});
th.start();
}
推荐答案
的的UserInterface只能由UI线程更新。你需要一个处理器,张贴到UI线程:
The UserInterface can only be updated by the UI Thread. You need a Handler, to post to the UI Thread:
private void startTimerThread() {
Handler handler = new Handler();
Runnable runnable = new Runnable() {
private long startTime = System.currentTimeMillis();
public void run() {
while (gameState == GameState.Playing) {
try {
Thread.sleep(1000);
}
catch (InterruptedException e) {
e.printStackTrace();
}
handler.post(new Runnable(){
public void run() {
tvTime.setText("" + ((System.currentTimeMillis() - this.startTime) / 1000));
}
});
}
}
};
new Thread(runnable).start();
}
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