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ProblemYou want to specify collision boundaries between your UI components on the screen so that they will not overlap one another.SolutionInstantiate... 阅读全文
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ProblemYou want your UI components to have gravity, so that if they are dragged up to the top of the screen, they will descend on their own. Combining... 阅读全文
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ProblemYou want to point out a specific location on a map to the user.SolutionUse built-in map view annotations. Follow these steps:1. Create a new cl... 阅读全文
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ProblemYou want to find the latitude and longitude of a device.SolutionUse the CLLocationManager class:#import "WSYViewController.h"#import @interface... 阅读全文
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ProblemYou want to allow the users of your app to select from a list of values.SolutionUse the UIPickerView class.DiscussionA picker view is a graphic... 阅读全文
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ProblemYou want to instantiate and display a map on a viewSolutionCreate an instance of the MKMapView class and add it to a view or assign it as a sub... 阅读全文
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HTTP HEAD 生成方法NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url cachePolicy:0 timeoutInterval:kTimeout];request.HTTPMethod = @"HE... 阅读全文