Refreshing UITableViewCell after fetching image data by dispatch_async
ios,objective-c,uitableview,setneedsdisplay
You'll could always reload the cell by calling [self.tableView reloadRows[email protected][indexPath] withRowAnimation:UITableViewRowAnimationAutomatic]; In order to prevent the infinite loop once you successfully download an image you'll want to cache the results. How long you cache is up to you. NSCache *imageCache = [[NSCache alloc] init]; imageCache.name = @"My Image Cache"; UIImage...
If I call setneedsdisplay frequently, how often will the drawrect be called? why is that?
From the documentation: When the actual content of your view changes, it is your responsibility to notify the system that your view needs to be redrawn. You do this by calling your view’s setNeedsDisplay or setNeedsDisplayInRect: method of the view. These methods let the system know that it should update...
Reload UIView and UILabel Frame
ios,uiview,autolayout,setneedsdisplay
Since you are using AutoLayout, you should change 'constant' value of the constraints associated with the views, rather than directly changing their frames. You can start by creating an IBOutlets/IBOutletCollection to the constraints you want to change and then using those IBoutlets you can change their 'constant' value....
setNeedsDisplay doesn't work on background thread
ios,objective-c,multithreading,setneedsdisplay
You can't update the user interface on a background thread. In your background thread, change [object setNeedsDisplay]; to [object performSelectorOnMainThread:@selector(setNeedsDisplay) withObject:nil waitUntilDone:NO]; ...
Tableview reload with setNeedsDisplay not working
ios,objective-c,uitableview,setneedsdisplay
I think you need to read up on the run loop and setNeedsDisplay (which I don't think does what you're expecting). Basically, the UI does not get updated until your code finishes executing. The pattern you need for displaying a complex calculation is something like this: -(void)Initialiseer { dispatch_async(dispatch_get_global_queue(QOS_CLASS_BACKGROUND, 0),...
UIViews SetNeedsDisplay not called
ios,xcode,swift,uiview,setneedsdisplay
Create an outlet for between your View on Storyboard and DrawGraph, suppose you name it DrawGraphV, be sure that view is Custom class DrawGraph, you don't need the method updateModell, just call directly DrawGraphV.SetNeedsDisplay