I agree that the description is confusing. Since I just grasped them, I’ll try to summarize: (__bridge_transfer <NSType>) op or alternatively CFBridgingRelease(op) is used to consume a retain-count of a CFTypeRef while transferring it over to ARC. This could also be represented by id someObj = (__bridge <NSType>) op; CFRelease(op); (__bridge_retained <CFType>) op or alternatively … Read more
Here is an example of all the options I have found as of Xcode 5.0.2 That was generated with this code: /** First line text. Putting \\n doesn’t create a new line.\n One way to create a newline is by making sure nothing is on that line. Not even a single space character! @a Italic … Read more
From the assembly code it can be seen that accessing weakPtr generates a objc_loadWeak call. According to the Clang documentation, objc_loadWeak retains and autoreleases the object and is equivalent to id objc_loadWeak(id *object) { return objc_autorelease(objc_loadWeakRetained(object)); } This (hopefully) explains why both if(strongPtr == weakPtr) … and NSLog(@”weakPtr: %@”, weakPtr); create additional autoreleased references. This … Read more
If you want a hackish way to do this that involves mucking with the objective-c runtime you can always use method swizzling (insert standard disclaimers here.) It will allow you to store the different methods as arbitrariliy named selectors, then swap them in at runtime as you need them.
At the moment, some #defines are converted and some aren’t. More specifically: #define A 1 …becomes: var A: CInt { get } Or: #define B @”b” …becomes: var B: String { get } Unfortunately, YES and NO aren’t recognized and converted on the fly by the Swift compiler. I suggest you convert your #defines to … Read more
By default, -performSelectorOnMainThread:withObject:waitUntilDone: only schedules the selector to run in the default run loop mode. If the run loop is in another mode (e.g. the tracking mode), it won’t run until the run loop switches back to the default mode. You can get around this with the variant -performSelectorOnMainThread:withObject:waitUntilDone:modes: (by passing all the modes you … Read more
I believe this is an issue with Xcode’s new interface builder. Did you happen to build your .xib using Xcode 4.5’s interface builder? I’ve run into this same problem just now, and I think that’s the problem. My app runs on iOS 6, but not anything older. And you need to make sure you turn … Read more
This is what I’ve done in my app, but without using UIImageView: UIImage *bottomImage = [UIImage imageNamed:@”bottom.png”]; //background image UIImage *image = [UIImage imageNamed:@”top.png”]; //foreground image CGSize newSize = CGSizeMake(width, height); UIGraphicsBeginImageContext( newSize ); // Use existing opacity as is [bottomImage drawInRect:CGRectMake(0,0,newSize.width,newSize.height)]; // Apply supplied opacity if applicable [image drawInRect:CGRectMake(0,0,newSize.width,newSize.height) blendMode:kCGBlendModeNormal alpha:0.8]; UIImage *newImage = … Read more
You should also ensure that you have breakpoints set for all exceptions. This will cause Xcode to stop at the line where the exception is occurring. Do the following [in Xcode 4]: In the Project Navigator on the left side of Xcode, click on the breakpoint navigator (almost all the way to the right hand … Read more
Yes, your second code snippit is perfectly valid. Every time -autorelease is sent to an object, it is added to the inner-most autorelease pool. When the pool is drained, it simply sends -release to all the objects in the pool. Autorelease pools are simply a convenience that allows you to defer sending -release until “later”. … Read more