Super slow lag/delay on initial keyboard animation of UITextField
Alright, this problem has been driving me nuts.
It takes roughly 3-4 seconds for the keyboard to pop up after I touch my UITextField . This only occurs on the first time the keyboard pops up since the app launched, afterwards the animation starts instantly.
At first I thought it was problem of loading too many images, or my UITableView , but I just created a brand new project with only a UITextField , and I still experience this problem. I'm using iOS 5, Xcode ver 4.2, and running on an iPhone 4S.
This is my code:
#import "ViewController.h"
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
UITextField *textField = [[UITextField alloc] initWithFrame:CGRectMake(20, 20, 280, 30)];
textField.borderStyle = UITextBorderStyleRoundedRect;
textField.delegate = self;
[self.view addSubview:textField];
}
@end
Is this a common problem for all apps?
Right now, the only way I can make it somewhat better is by having textField become/resign first responder in viewDidAppear , but that doesn't solve the problem entirely - it just loads the delay onto when the view loads instead. If I click on textField immediately when the view loads, I still get the problem; if I wait 3-4 seconds after the view loads before touching the textField, I don't get the delay.
Before you implement any exotic hacks to get around this problem, try this: stop the debug session, close the app from multitasking, unplug your device from the computer and run the app normally by tapping its icon. I have seen at least two cases in which the delay only occurs while the device is plugged in.
So the problem is NOT just limited to the first install as I had previously thought, but happens every time the app is launched. Here's my solution that solves the issue completely.
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
// Preloads keyboard so there's no lag on initial keyboard appearance.
UITextField *lagFreeField = [[UITextField alloc] init];
[self.window addSubview:lagFreeField];
[lagFreeField becomeFirstResponder];
[lagFreeField resignFirstResponder];
[lagFreeField removeFromSuperview];
}
Yeah, I also got a few seconds delay on the latest iPhone 4s. Don't panic. For some reasons, it only happens the first time the app is loaded from Xcode in Debug. When I did Release, I don't get the delay. Just forget it...
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