cs193p

问题 I'm very new to swift, and I'm doing the Stanford course on iTunes U. I've been following along fine, but I've encountered an error that I'm unable to understand: 2015-06-29 18:45:35.080 calculator2[9780:4828233] *** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<calculator2.ViewController 0x7fae561041b0> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key enter.' I've uploaded my repo to github here. Any help is very much

问题 SWIFT / IOS 8.2 I am trying to set my CalculatorViewController as the delegate target so I can get data - but I seem to be setting it wrong: "EXC_BAD_ACCESS (code:2)" (in GraphView.swift) protocol CalculatorViewDataSource: class { func calculateYForXEquals(sender: CalculatorViewController, currentX: CGFloat) ->CGFloat? } class GraphView: UIView { weak var calculatorViewDataSource: CalculatorViewDataSource? //... } (in GraphViewController.swift) class GraphViewController: UIViewController {

问题 The code is from Stanford CS193p. I added a NSLog to check it out. The label seems not being initialized. Any idea? @interface AskerViewController() <UITextFieldDelegate> @property (weak, nonatomic) IBOutlet UILabel *questionLabel; @property (weak, nonatomic) NSString *question; @end @implementation AskerViewController @synthesize questionLabel = _questionLabel; @synthesize question = _question; - (void)setQuestion:(NSString *)question { _question = question; self.questionLabel.text =

问题 I was playing with a simple OCUnit test for an iPhone app, and just wanted to assert that the app delegate was an instance of the class that I expected it to be. I didn't expect this test to be very useful, but it turned out to reveal a misunderstanding that I have regarding Objective C. I first get a reference to the delegate. Then I log the class name of what comes back. In my case, the output correctly says "app delegate's class name is CalculatorAppDelegate". However, the assertion on the

问题 I was playing with a simple OCUnit test for an iPhone app, and just wanted to assert that the app delegate was an instance of the class that I expected it to be. I didn't expect this test to be very useful, but it turned out to reveal a misunderstanding that I have regarding Objective C. I first get a reference to the delegate. Then I log the class name of what comes back. In my case, the output correctly says "app delegate's class name is CalculatorAppDelegate". However, the assertion on the

问题 I've looked at this answer, but since I am new to Swift and am following along code that should work from Stanford CS193's course, I'm a bit confused. This is from an exercise that involves building a calculator. In the model I have these functions: private func evaluate() -> Double? { let (result, remainder) = evaluate(opStack) return result } func pushOperand(operand: Double) { opStack.append(Op.Operand(operand)) return evaluate() } func performOperation(symbol: String) { if let operation =

问题 I'm trying to follow along the Stanford CS193p iOS programing lectures. One of the demo programs, called "Happiness" creates two UIViewControllers, a "PsychViewController" and a "HappinessViewController." It segues from the PsychViewController to the HappinessViewController using a target action method. The following code keeps throwing this exception: "-[UIViewController setHappiness:]: unrecognized selector sent to instance" Here's the offending code: -(void)prepareForSegue:

问题 I'm going through the Stanford CS193P course on iTunesU and am a little puzzled on how to do the recently viewed photos portion on assignment 4. In the assignment we are to have a tab bar controller with two tabs. 1st tab is a navigation controller that will show a table of places, which will push a table of photo names, which will push a scroll view with a photo 2nd tab is a navigation controller that will show a table of recently viewed photos, which will push a scroll view with a photo. I

问题 I am learning the course CS193P(IOS develop) on itunes and I just started assignment2. I got stuck on the task that asks me to restart the game. A little bit background on the project: I am writing code for the newly added action method for the restart button in my CardGameViewController. I have two private properties: game and deck . I use lazy initialization in the CardGameViewController to initialize them when user first touch a button(flip a card).(The original project that the professor

问题 I'm working on the CS193p coursework from Stanford (I'm not a Stanford student I'm just trying to learn), assignment number 5, where we have to get images from Flickr using calls to the Flickr api. I'm only trying to download a list of the pictures and print them out to the console, but I'm getting an NSURLErrorDomain with code -1005. The error message I am printing out is below: error: Error Domain=NSURLErrorDomain Code=-1005 "The operation couldn’t be completed. (NSURLErrorDomain error