Can I disable UIPickerView scroll sound? - objective-c

I want to disable the annoying clicks that the UIPickerView generates upon scrolling up and down. Is there a way to do this? I want to play short sounds for each item that the picker view lands upon. It gets ruined by the built in sound.
I understand that the picker sounds can be turned off globally by switching off the keyboard sounds in iPhone/iPod settings. But is there a way to programatically do this?
Any help will be much appreciated!
Thanks

I've been struggling with a UIPickerView sound issue, and even though it's only partially relevant to the original question, I'm posting the problem/solution here because this topic keeps coming up in my search results so I think anyone else in the same boat may end up here too…
I needed to initialize a UIPickerView to restore the currently selected row from saved data. Simple, right? In viewDidLoad, just call the selectRow:inComponent:animated method of UIPickerView:
[myPicker selectRow:currentRowIndex inComponent:0 animated:NO];
This works as expected, but has a side effect that it generates a single "click" sound as if the user had scrolled the control. The click sound only occurs when running on a device (not the simulator), and only if the device has iOS 3.x installed (I tested with 3.1.3 and 3.2). This was apparently a bug in iOS that was fixed starting with iOS 4.0. But if you need to target Gen1 iPhone, you're stuck with iOS 3.1.3 where this problem is present.
I discussed the issue with Apple DTS, but they were unable to suggest any workaround other than upgrading to 4.0. I asked if they would make an exception and permit the use of the undocumented setSoundsEnabled mentioned above (which does actually solve the problem). The answer was, "There are no exceptions."
After some additional detective work, I discovered that you can prevent the sound from occurring by temporarily removing the UIPickerView from the superview, call selectRow, then re-add it to the superview. For example, in viewDidLoad:
UIView *superview = [myPicker superview];
[myPicker removeFromSuperview];
[myPicker reloadAllComponents];
[myPicker selectRow:currentRowIndex inComponent:0 animated:NO];
[superview addSubview:myPicker];
This gets rid of the extraneous click sound without using undocumented/private APIs so should pass Apple's approval process.

After using this specific undocumented api for over a year on the App Store Apple finally asked me to remove it from my App. It is very frustrating for audio apps to have that damn click sound. The best advice is to share with users that the picker sound can be disabled globally in the settings application under "Sounds" and setting "Keyboard Clicks" to "Off". I also strongly recommend visiting https://bugreport.apple.com/ and filing a bug for UIPickerView, as it can cause distortion in audio applications when the picker click is played.

they have just rejected an app of mine because the use of undocumented api's...thats one of them.

Someone I know says he got this past the App Store review just last week:
// Hide private API call from Apple static analyzer
SEL sse = NSSelectorFromString([NSString stringWithFormat:#"%#%#%#", #"set",#"Sounds",#"Enabled:"]);
if ([UIPickerView instancesRespondToSelector:sse]) {
IMP sseimp = [UIPickerView instanceMethodForSelector:sse];
sseimp(self.thePicker, sse, NO);
}

There is an undocumented way (I'm actually not sure if it is still available in iphone 3.0) but here it is any way
#import <UIKit/UIKit.h>
#interface SilintUIPickerView: UIPickerView
{ }
- (void) setSoundsEnabled: (BOOL) enabled;
#end
use this subclass instead and call [view setSoundsEnabled: NO]
I'm interested in knowing how it goes in the latest SDK, give it a shot and let us know.

Could this trick work? Someone was able to suppress the camera shutter sound effect by playing an inverted copy of the sound at the same moment: https://stackoverflow.com/a/23758876/214070

Maybe this not the answer for this particular question, but I had a similar problem - set minimumDate for datePicker, and I wanted set it without annoying "click" sound. After some time found very simple solution:
datePickerCustomTime.minimumDate = [[NSDate date] dateByAddingTimeInterval:300]// min time to set = now + 5 min
[datePickerCustomTime setDate:[[NSDate date] dateByAddingTimeInterval:300] animated:NO];

I found small quickie solution for this try below
UIPickerView *pickerView = [[UIPickerView alloc] initWithFrame:CGRectMake(0, yPickerView, VIEW_WIDTH, PICKERVIEW_HEIGHT)];
pickerView.delegate = self;
pickerView.dataSource = self;
pickerView.showsSelectionIndicator = YES;
pickerView.alpha = 0.8f;
pickerView.tag = fieldTag;
[pickerView selectRow:pickerViewSelectedIndex inComponent:0 animated:NO];
set the animated:NO for selectRow: method

Related

Something very strange UITextView in iOS 7 ... not in iOS 6?

I'm creating a UITextView:
greetingTextView = [[UITextView alloc] initWithFrame:greetingRect];
Using it fine, but when the ViewController it is attached to deallocs I'm getting memory leaks ONLY in iOS 7 ? I'm even Nulling the greetingTextView out of desperation but to no effect:
[greetingTextView.undoManager removeAllActions];
greetingTextView.delegate = Nil;
[greetingTextView removeFromSuperview];
greetingTextView = Nil;
The leaks are in this image:
So it appears something to do with the UITextView UndoManager ? But why only in iOS 7 ?
Regards
I face a similar situation, and after hunting around and some trail and error, i noticed that when ARC is disabled for that particular file, the strange behavior stopped and no memory leaks occurred. check here for how to disable arc for a particular file
You'll need to empty out the undo manager if you want any object you add to it to be released.
Review the steps laid out in this document :
https://developer.apple.com/library/ios/documentation/cocoa/Conceptual/UndoArchitecture/Articles/CleaningUndoStack.html
It did occurs to me once when I didn't specify the delegate of a UITextField. After the delegate was set everything went normal. Hope it helps. BTW, I'm using Storyboard.

NSImageView setImage causing NSView not correctly initialized

I'm writing a networking program which sends an image from an iPhone to a Mac. I have the connection going fine, and passing data alright, but my problem is when I have the image sent over I try to display it and get the following warning:
NSImageView(0x101321fd0) - NSView not correctly initialized. Did you
forget to call super?
Here is the code, it's the "setImage" command throwing the error.
This is my first major venture into Objective-C, I'm worried I messed up something with the xib but I can't be sure.
imageView = [NSImageView alloc];
[imageView setImage:theImage];
NSLog(#"Should be able to see image now..");
If this is too vague for a direct answer then any tips, references or tutorials you can guide me to would be very welcome.
Thanks for your time.
You forget to init the imageView.
imageView = [[NSImageView alloc] initWithFrame:someFrame]

Upgrading app from IOS4 to IOS5

I have an IOS5 app which uses following function
[self.presentingViewController dismissModalViewControllerAnimated:YES];
and who works perfectly on IOS4 but suddenly I discovered that this function doesn't exists on IOS5 so I had to use this other equivalent one
[self.parentViewController dismissModalViewControllerAnimated:YES]
Now I've got the following issue: IOS4 users are not able to install my app due to this non existing function in IOS4 and what is even worse, the app is available on Apple's App Store but is only functional of IOS5 users. Another related issue us that the app suddenly stopped working on iPads equipped with Wifi, those connected to 3G networks operate normal.
Is there anything I missed trying to compile this new app version?
Thanks in advance!
You can check for existence of the property like this:
if([self respondsToSelector:#selector(presentingViewController)])
[self.presentingViewController dismissModalViewControllerAnimated:YES];
else
[self.parentViewController dismissModalViewControllerAnimated:YES];
Code it this way:
if ([self respondsToSelector:#selector(parentViewController)])
[self.parentViewController ...];
else
[self.presentingViewController ...];
(This is uncompiled, untested, etc.)
The point is that you can (and should) test for capabilities, and then act accordingly. In this case, if the iOS5 method is available, use that one. If not, use the old one, which also means its a pre-iOS5 device.
The way to go is twofold:
compiling your app against the latest SDK version, but also set the deployment target to the oldest version that you want to support; this will ensure that the app is listed properly in the App Store;
checking before using any method/feature that is only available on a later version; this will ensure that you app will not crash and can be done by means of conditional compilation, e.g.:
k
#if __IPHONE_OS_VERSION_MAX_ALLOWED >= 40000
if ([[UIApplication sharedApplication] respondsToSelector:#selector(beginBackgroundTaskWithExpirationHandler:)])
{
UIBackgroundTaskIdentifier bgTask = [[UIApplication sharedApplication] eginBackgroundTaskWithExpirationHandler:^{}];
// Perform work that should be allowed to continue in background
[[UIApplication sharedApplication] endBackgroundTask:bgTask];
}
#endif
this is quite convoluted if you have to do it in many places. You may have a look at this very good post to learn how to improve upon that example.
I have built a category that add presentingViewController on iOS 4.
(It disables itself on iOS 5.)
It works seamlessly; Just include 2 files.
Please see backward-modal.
I hope this benefits you as much as it does to me; It makes your code more clean!

Objective-C –Setting network indicator to visible after application is launched

Is it possible to set [[UIApplication sharedApplication] setNetworkActivityIndicatorVisible:YES]; in - application:didFinishLaunchingWithOptions:
It doesn't seem to work for me.
It works for me, check if you turn it down at some place later.
Check if it gets turned off as wcrane suggested but also make sure you don't have some other 3rd party library in your project that possibly does that. Also, try calling it after a delay of, say, 0.5s or something. E.g.
[self performSelector:#selector(turnOnNetworkIndicator) withObject:nil afterDelay:0.5]

How do I duplicate iPad display over TV out?

Is it possible to simply duplicate ipad display to TV out (assuming both have same resolution)?
Code like this doesnt seem to work (it is a pretty naive implementation)
int i=0;
for (UIScreen *screen in [UIScreen screens])
{
if(i>0)
{
UIWindow* extWindow = [[UIWindow alloc]init];
extWindow.screen =screen;
[extWindow addSubview:viewController.view];
[extWindow makeKeyAndVisible];
}
i++;
}
[window addSubview:viewController.view];
[window makeKeyAndVisible];
Code like this doesnt seem to work (it
is a pretty naive implementation)
This code looks like a mishmash. I haven't used external screens before, but your inner if block is creating anonymous UIWindow objects, assigning a property, and then leaking them at the end of the block (no release) -- and that definitely won't do what you intend.
You should consult the iPad Programming Guide, specifically, Support for External Displays and Projectors, which summarizes how your code should be written.
If you need this for a demo presentation, then there are few apps that will duplicate the screen for you while running your app like TVOut, TVOut2, Screenspltr. However there is a catch, these apps are not approved by Apple therefore are not in the app store, in order to install them you'll need to jailbreak it and it comes with the involved risks. However for a quick dome it is probably the best solution.