ios5

问题 Closed. This question is off-topic. It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed 7 years ago . I accidentally upgraded my iPhone 4 on 5.1 and now I can't test on Xcode 4.2 on my snow leopard. I don't want to upgrade to lion to download xcode 4.3 because I heart many people that said it slowed down their macs and had other several problems. Is there a way to downgrade from iOS 5.1 to iOS 5.0 and be able to

问题 I am having problem passing value to a IBOutlet property of destinationViewController but it works fine on ordinary property see code below - (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender { if ([segue.identifier isEqualToString:@"NewsCellToDetail"]) { testViewController *viewController = segue.destinationViewController; viewController.titleLabel.text = @"test"; // set the IBOutlet label text to something NSLog(@"%@",viewController.titleLabel.text); // this will output to

问题 I'm diving into iOS programming and I'm having difficulty getting my head around the idea of Dot Notation and Method Notation. As far as I understand it, Dot Notation can be used to invoke setters/getters on properties and is much more cleaner to write/read. Method Notation is used to send messages to objects to manipulate them etc. Could someone give me a simple explanation as to why the following two statements are essentially different and one will compile but the other will instead fail

问题 Hello i need to create a progressView when i load data from my webservice. Actually the expectedContentLength alway return -1. After look lots of similary problem it looks like my webservice never send the Content-Length:. Then i check with CURL and here is the result : < HTTP/1.1 200 OK < Date: Thu, 21 Jun 2012 10:04:39 GMT < Server: Apache/2.2.16 (Debian) < X-Powered-By: PHP/5.3.3-7+squeeze9 < cache-control: no-cache < Vary: Accept-Encoding < Content-Type: text/html; charset=UTF-8 < Content

问题 (Using iOS 5 and Xcode 4.2) I have an MKMapView and want to draw a circle of 1000m radius around the user location. On the surface it would seem that implementing the mapView:viewForAnnotation: map view delegate method, and adding a custom MKAnnotationView for the users location, would be a perfect solution. It would look something like this: - (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>)annotation { // If it's the user location, return my custom

问题 I am aware of how to save metadata using ALAssets. But, I want to save an image, or upload it somewhere, with exif intact. I have exif data as an NSDictionary. But how can I inject it properly into a UIImage (or probably an NSData JPEG representation)? 回答1: UIImage does not contain metadata information (it is stripped). So if you want to save it without using the imagepicker method (not in camera roll): Follow the answer here to write to a file with the metadata intact: Problem setting exif

问题 The new Nike+ GPS application for iOS 5 is able to process accelerometer events in the background (thus allowing for indoor treadmill tracking). How is this possible? When I put my application in background, it ceases receiving events. I use the standard UIAccelerometer API. 回答1: For the sake of providing an answer to this question, even though it is already self answered... "If you use the newer Core Motion API, you can receive updates in the background." Here is an example: - (void

问题 My objective is to create a tabbed application, then the view for each of the tabs are constructed in separate storyboards. My mainstoryboard is a tab view. Then I create a secondary storyboard (storyboard#2) with 2 View Controllers. The first view controller (also ticked as initial) have a button, and segue (modal) to 2nd view. I managed to load the view by subclassing and overriding loadView from storyboard#2. Here's the simulator output. When click on the "click me" button, I get a EXC_BAD

问题 As a beginning iPhone programmer, what is the best practice for writing apps to be used either with iOS 5 or older versions? Specifically, should I continue using the release/retain of data, or should I ignore that? Does it matter? 回答1: It's up to you. You can write apps using ARC (Automatic Reference Counting), and Xcode will write "glue code" to allow your ARC enabled apps to run on iOS 4, no modifications required. However, certain things wont work, and most noticeably many libraries you

问题 As a beginning iPhone programmer, what is the best practice for writing apps to be used either with iOS 5 or older versions? Specifically, should I continue using the release/retain of data, or should I ignore that? Does it matter? 回答1: It's up to you. You can write apps using ARC (Automatic Reference Counting), and Xcode will write "glue code" to allow your ARC enabled apps to run on iOS 4, no modifications required. However, certain things wont work, and most noticeably many libraries you