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UIView with rounded corners

My login view has a subview which has a UIActivityView and a UILabel saying "Signing In…". This subview has corners which aren't rounded. How can I make them round?

Is there any way to do it using a nib/xib?

Cocoa: What's the difference between the frame and the bounds?

UIView and its subclasses all have the properties frame and bounds. What's the difference? (Please don't quote the Apple docs — I've already read them and did not understand.)

How to add a touch event to a UIView?

How do I add a touch event to a UIView?
I try:

UIView *headerView = [[[UIView alloc] initWithFrame:CGRectMake(0, 0, tableView.bounds.size.width, nextY)] autorelease];
[headerView addTarget:self action:@selector(myEvent:) forControlEvents:UIControlEventTouchDown];
// ERROR MESSAGE: UIView may not respond to '-addTarget:action:forControlEvents:'

I don't want to create a subclass and overwrite

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event

Thanks!

How to set iPhone UI View z index?

I want to move one view on top of another, how can I know the z index of the view, and how to move on to top? Thank you.

UIView frame, bounds and center

I would like to know how to use these properties in the right manner.

As I understand, frame can be used from the container of the view I am creating. It sets the view position relative to the container view. It also sets the size of that view.

Also center can be used from the container of the view I'm creating. This property changes the position of the view relative to its container.

Finally, bounds is relative to the view itself. It changes the drawable area for the view.

Can you give more info about the relationship between frame and bounds? What about the clipsToBounds and masksToBounds properties?

UIView's frame, bounds, center, origin, when to use what?

UIView has the properties frame, bounds, center, and origin, and they all seem to be interrelated. Most of the time, I deal with frame when setting the position and size of a UIView. I understand that frame is using global coordinate system and bounds is using coordinate of the local view (therefore its x and y are 0, but not always), but it's still confusing to me when to use what.

Under what context (and what's the right time) the other properties (bounds, center, origin) should be used?

Autoresizing masks programmatically vs Interface Builder / xib / nib

I had some confusions, which I think I have resolved them now, but just wanted confirmation.

I was in an (probably false) assumption that enabling the right margin indicator in xib is equivalent to using UIViewAutoresizingFlexibleLeftMargin inside code and so on.

So, I used to think according to this snapshot:

Later today I had to cross check, and stumbled upon this thread.

And also the apple documentation, entitled with the section with title - "Handling Layout Changes Automatically Using Autoresizing Rules" in this link: http://developer.apple.com/library/ios/#documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/CreatingViews/CreatingViews.html

So I now have a renewed concept in my mind as to how setting autoresizing masks programmatically would be equivalent to xib settings:

Scenario 1: Setting only (UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight) is equivalent to:

In XIB?

Scenario 2: Setting (UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin | UIViewAutoresizingFlexibleTopMargin | UIViewAutoresizingFlexibleBottomMargin) in code is equivalent to:

In XIB?

Are my 2 renewed scenarios correct? Am I right now in my understanding?

Thanks, Raj

UIView Infinite 360 degree rotation animation?

I'm trying to rotate a UIImageView 360 degrees, and have looked at several tutorials online. I could get none of them working, without the UIView either stopping, or jumping to a new position.

• How can I achieve this?

The latest thing I've tried is:

[UIView animateWithDuration:1.0
                      delay:0.0
                    options:0
                 animations:^{
                     imageToMove.transform = CGAffineTransformMakeRotation(M_PI);
                 } 
                 completion:^(BOOL finished){
                     NSLog(@"Done!");
                 }];

But if I use 2*pi, it doesn't move at all (since it's the same position). If I try to do just pi (180 degrees), it works, but if I call the method again, it rotates backwards.

EDIT:

[UIView animateWithDuration:1.0
                      delay:0.0
                    options:0
                 animations:^{
                     [UIView setAnimationRepeatCount:HUGE_VALF];
                     [UIView setAnimationBeginsFromCurrentState:YES];
                     imageToMove.transform = CGAffineTransformMakeRotation(M_PI);
                 } 
                 completion:^(BOOL finished){
                     NSLog(@"Done!");
                 }];

doesn't work either. It goes to 180 degrees, pauses for a split second, then resets back to 0 degrees before it starts again.

UIView with rounded corners and drop shadow?

I've literally tried everything I could but none of them work for a custom UIView... I just wanted a blank white view with rounded corners and a light drop shadow (with no lighting effect). I can do each of those one by one but the usual clipToBounds/maskToBounds conflicts occur.

iPhone - Get Position of UIView within entire UIWindow

The position of a UIView can obviously be determined by view.center or view.frame etc. but this only returns the position of the UIView in relation to it's immediate superview.

I need to determine the position of the UIView in the entire 320x480 co-ordinate system. For example, if the UIView is in a UITableViewCell it's position within the window could change dramatically irregardless of the superview.

Any ideas if and how this is possible?

Cheers :)

Get to UIViewController from UIView?

Is there a built-in way to get from a UIView to its UIViewController? I know you can get from UIViewController to its UIView via [self view] but I was wondering if there is a reverse reference?

how to set cornerRadius for only top-left and top-right corner of a UIView?

Is there a way to set cornerRadius for only top-left and top-right corner of a UIView?

EDIT:

I tried the following, but it end up not seeing the view anymore. Anything wrong with the code below?

UIView *view = [[UIView alloc] initWithFrame:frame];

CALayer *layer = [CALayer layer];
UIBezierPath *shadowPath = [UIBezierPath bezierPathWithRoundedRect:frame byRoundingCorners:(UIRectCornerTopLeft|UIRectCornerTopRight) cornerRadii:CGSizeMake(3.0, 3.0)];
layer.shadowPath = shadowPath.CGPath;
view.layer.mask = layer;

iPhone UIView Animation Best Practice

What is considered best practice for animating view transitions on the iPhone?

For example, the ViewTransitions sample project from apple uses code like:

CATransition *applicationLoadViewIn = [CATransition animation];
[applicationLoadViewIn setDuration:1];
[applicationLoadViewIn setType:kCATransitionReveal];
[applicationLoadViewIn setTimingFunction:[CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseIn]];
[[myview layer] addAnimation:applicationLoadViewIn forKey:kCATransitionReveal];

but there are also code snippets floating around the net that look like this:

[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:0.75];
[UIView setAnimationDelegate:self];
[UIView setAnimationTransition:UIViewAnimationTransitionFlipFromRight forView:myview cache:YES];
[myview removeFromSuperview];
[UIView commitAnimations];

What is the best approach? If you could provide a snippet as well it'd be much appreciated.

NOTE: I've been unable to get the second approach to work correctly.

How to use UIVisualEffectView?

Could someone give a small example of applying the blur to an image? I've been trying to figure out the code for a while now :( still new at obj c!

The UIVisualEffectView provides a simple abstraction over complex visual effects. Depending on the desired effect, the results may affect content layered behind the view or content added to the view’s contentView.

Apply a UIVisualEffectView to an existing view to apply a blur or vibrancy effect to the exiting view. After you add the UIVisualEffectView to the view hierarchy, add any subviews to the contentView of the UIVisualEffectView. Do not add subviews directly to the UIVisualEffectView itself.

https://developer.apple.com/library/prerelease/ios/documentation/UIKit/Reference/UIVisualEffectView/index.html#//apple_ref/occ/instp/UIVisualEffectView/contentView

UIViewController. viewDidLoad vs. viewWillAppear: What is the proper division of labor?

I have always been a bit unclear on the type of tasks that should be assigned to viewDidLoad vs. viewWillAppear: in a UIViewController subclass. For example, I am doing an app where I have a UIViewController subclass hitting a server, getting data, feeding it to a view and then displaying that view. What are the pros and cons of doing this in viewDidLoad vs. viewWillAppear?

Thanks in advance.

Cheers, Doug