Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
462 views
in Technique[技术] by (71.8m points)

objective c - Updating UILabel in the middle of a for() loop

I have a method with a for() loop. In that loop, mylabel.text is updated many times. However, the actual label does not update on the screen until the method is done, updating with the last value created in the for() loop.

Using an NSLog, which does update in the middle of the for() loop, I see the value indeed changing for the label many times.

Is it the general practice in iOS to not update labels in the middle of the for() loop? I would imagine there is a way to do this.

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

You can make the UI update by telling the run loop to run like this:

for (NSInteger i = 0; i < 10; i++) {
    [label setText:...];
    [[NSRunLoop currentRunLoop] runMode:NSDefaultRunLoopMode beforeDate:[NSDate distantPast]];
}

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...