Question

我已经看到了一些关于如何在后台运行NSTask的好信息，尽管这并不完全是我想做的事情。我想做的是定期在后台运行NSTask（每30秒一次），然后杀死它;这可能是我想做的一个例子：

NSTask *theTask = [ [ NSTask alloc ] init ];
NSPipe *taskPipe = [ [ NSPipe alloc ] init ];

[ theTask setStandardError:taskPipe ];
[ theTask setStandardOutput:taskPipe ];
[ theTask setLaunchPath:@"/bin/ls" ];
[ theTask setArguments:[ NSArray arrayWithObject:@"-l" ] ];
[ theTask launch ];

// Wait 30 seconds, then repeat the task

Answer 1

也许你可以简单地让线程睡眠并在do循环中等待30秒：

do {

[ theTask launch ]; //Launch the Task
sleep(30);          //Sleep/wait 30 seconds 

} while (someCondition);

否则您可以使用NSTimer：

NSTimer *t = [NSTimer scheduledTimerWithTimeInterval: 30.0
                      target: self
                      selector:@selector(onTick:)
                      userInfo: nil repeats:YES];


- (void)onTick:(NSTimer *)timer {
    //In this method that will be get called each 30 seconds, 
    //you have to put the action that you want to perform ...
    [ theTask launch ];
}

Objective-C，定期在后台运行NSTask

1 个答案: