Start and stop a thread repeatedly in Android
Here I have a method called Method1() that will start a thread when the method is called at odd time and stop the method at even time. When I call the method via the Button.onClick event, the following code fragment works. Is this the right way to pause and resume threads? Is my method thread-safe?
Thread sampleThread = null;
..
..
..
private void Method1(){
if(sampleThread == null){
sampleThread = new Thread(){
@Override
public void run() {
while(true) {
Log.d(TAG,"Inside Thread");
}
}
};
sampleThread.start();
}else {
sampleThread.interrupt();
}
}
Solution
If Method1 is called frequently, I suggest you’d better set a flag that enables it to resume threads and disable it to pause threads. Because if you create and destroy threads frequently, a lot of CPU and memory will be wasted. You can use it like this:
public class MyThread extends Thread{
volatile boolean isRunning = true;//make sure use volatile keyword
@Override
public void run() {
while(isRunning) {
Log.d(TAG,"Inside Thread");
}
}
public void setRunning(boolean running){
this.isRunning = running;
}
};
When you want to pause, call thread.setRunning (
false), restart it, call thread.setRunning (true).
Your solution is almost fine if not so often, but I think you should add it
sampleThread = null
In sampleThread.interrupt(); After that, otherwise the next time you pause it, it interrupts a non-active thread and may throw an exception.