Objective c 在ios上延迟后启动UIActivityIndicator
仅当操作花费太多时间时,我才想启动UIActivityIndicator:Objective c 在ios上延迟后启动UIActivityIndicator,objective-c,ios,uiactivityindicatorview,Objective C,Ios,Uiactivityindicatorview,仅当操作花费太多时间时,我才想启动UIActivityIndicator: - (void) continueLaunch { //operations //..... [activityIndic stopAnimating]; } //my current method - (void)lauchApplication { [activityIndic startAnim
- (void) continueLaunch {
//operations
//.....
[activityIndic stopAnimating];
}
//my current method
- (void)lauchApplication {
[activityIndic startAnimating];
[self performSelector:@selector(continueLaunch) withObject:nil afterDelay:0.0f];
}
//what I want to do
- (void)lauchApplication {
if ([self performSelector:@selector(continueLaunch) withObject:nil afterDelay:0.0f]duration > 1 second){
[activityIndic startAnimating];
}
}
我该怎么做呢?我认为最好的办法是在您想要等待的持续时间之后启动指示器,如果在该持续时间之前的某个时刻发生了什么事情,您可以取消它:
[self performSelector:@selector(startAnimation) withObject:nil afterDelay:1.0f]
对于取消它(来自Apple Doc):
要取消排队消息,请使用
取消以前的性能请求,目标:或
cancelPreviousPerformRequestsWithTarget:selector:object:method
一种可能的解决办法是: