I can get the UIPinchGestureRecognizer handler to work with scaling an object but I don't want to scale I want to change the size. For example I have a UIView and I've attacked a UIPinchGestureRecognizer gesture to it and if the user pinches I want to change the width of the UIView to match the pinch. I don't want to scale it so the UIView is larger(zooming)
If you have the UIPinchGestureRecognizer call a method pinch, you can do:
- (void) pinch:(UIPinchGestureRecognizer *)pinch
{
CGRect frame = [self.view frame];
frame.size.width = frame.size.width * pinch.scale;
[self.view setFrame:frame];
}
Related
I'm doing a rotation animation on a view and want it to rotate around the view's center X and bottom Y. I change the anchorPoint and position of the layer and run the animation. Here's my code:
- (void)viewDidLoad {
[super viewDidLoad];
_imageView = [UIImageView newAutoLayoutView];
_imageView.image = [PCImage imageNamed:#"Umbrella"];
[self.view addSubview:_imageView];
[_imageView autoAlignAxisToSuperviewAxis:ALAxisVertical];
[_imageView autoPinEdgeToSuperviewEdge:ALEdgeBottom];
}
- (void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
CGPoint newPosition = CGPointMake(CGRectGetMidX(_imageView.frame), CGRectGetMaxY(_imageView.frame));
NSLog(#"frame %#, new position %#", NSStringFromCGRect(_imageView.frame), NSStringFromCGPoint(newPosition));
_imageView.layer.anchorPoint = CGPointMake(.5, 1.0);
_imageView.layer.position = newPosition;
[UIView animateKeyframesWithDuration:2.0 delay:2.0 options:UIViewKeyframeAnimationOptionCalculationModeLinear | UIViewKeyframeAnimationOptionAutoreverse | UIViewKeyframeAnimationOptionRepeat animations:^{
[UIView addKeyframeWithRelativeStartTime:0.0 relativeDuration:.1 animations:^{
_imageView.transform = CGAffineTransformMakeRotation(M_PI / 64);
}];
} completion:nil];
}
edit
The rotation is working, but the view 'jumps' upward to a new position first, where the view's bottom is now where the view's center Y was when first laid out. I thought changing the anchorPoint and updating the position would prevent the jumping. The view is pinned to the superview's bottom edge, and center X to the superview's center X in autolayout, if that might matter. Any ideas?
edit2
I've read other good posts on this like the following but I must be missing something..
Scale UIView with the top center as the anchor point?
I ended up changing the view to not use autolayout after reading this post:
Adjust anchor point of CALayer when autolayout is used
Looks like transforms and autolayout aren't designed to work well together.
_imageView = [UIImageView new];
_imageView.image = [PCImage imageNamed:#"Umbrella"];
_imageView.frame = CGRectMake(0, kScreenHeight - _imageView.image.size.height, _imageView.image.size.width, _imageView.image.size.height);
[self.view addSubview:_imageView];
At some point hoping to experiment with other ideas in that post.
I have created a paginated UIScrollView with three subviews. It works great when testing on an iPhone 5 in landscape (the orientation I designed at) but it breaks whenever the device resolution changes.
How can I make the frame scale to the correct resolution, no matter the device or orientation?
- (void)viewDidLoad {
CGRect frame;
frame.origin.x = self.scrollView.frame.size.width * i;
frame.origin.y = 0;
frame.size = self.scrollView.frame.size;
}
- (IBAction)changePage {
CGRect frame;
frame.origin.x = self.scrollView.frame.size.width * self.pageControl.currentPage;
frame.origin.y = 0;
frame.size = self.scrollView.frame.size;
[self.scrollView scrollRectToVisible:frame animated:YES];
pageControlBeingUsed = YES;
}
Put your scroll view inside another, custom view. In the custom view, implement layoutSubviews something like this.
#interface ViewScalesOneSubview : UIView
#property UIView *scalingSubview;//subview to scale
#end
#implementation ViewScalesOneSubview
-(void) layoutSubviews {
[super layoutSubviews];
CGRect parentBounds = [self bounds];
CGRect childBounds = [scalingSubview bounds];//unscaled
CGFloat scale = parentBounds.width / childBounds.width;
CGAffineTransform transform = CGAffineTransformMakeScale( scale , scale );
//fiddle with x,y translation to position as you like
scalingSubview.transform = transform;
}
#end
Give the custom view autoresizing so it fits the window or whatever container and changes with rotation. Do not give the scroll view autoresizing, as it will conflict with this custom layoutSubviews. When the custom view changes size, it will scale the scalingSubview to fit. By using the same scale for both axis, it will preserve aspect ratio. You could scale to fit instead, or use height instead of width or whatever.
Edit:
To resize the view, as opposed to scaling the view, set the autoresizing mask.
scrollView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
https://developer.apple.com/library/ios/documentation/uikit/reference/UIView_Class/UIView/UIView.html#//apple_ref/occ/instp/UIView/autoresizingMask
You can also do this in interface builder.
I have an UIScrollview and which contains UIView as a subview like,
here i can able to drag the UIView inside the ScrollView, when the uiview goes to at END RIGHT or END LEFT the uiview disappears inside scrollview, after that i has to scroll the scrollview then i can able to see the uiview, here i need to SCROLL THE SCROLLVIEW when uiview comes at the rightside or left side, for that i used this code but not working.
[myscrollview scrollRectToVisible:myview.frame animated:YES];
Here I have used on UIButton (as it is already used in one of my application I dont need to write whole code again)
[cropRectangleButton addTarget:self action:#selector(imageMoved:withEvent:) forControlEvents:UIControlEventTouchDragInside];
The cropRectangleButton is one UIButton and the imageMoved:withEvent: method is as below
- (IBAction) imageMoved:(id)sender withEvent:(UIEvent *)event
{
CGPoint point = [[[event allTouches] anyObject] locationInView:self.view];
CGPoint prev = lastTouchDownPoint;
lastTouchDownPoint = point;
CGFloat diffX = point.x - prev.x;
CGFloat diffY = point.y - prev.y;
UIControl *button = sender;
CGRect newFrame = button.frame;
newFrame.origin.x += diffX;
newFrame.origin.y += diffY;
scrollView.contentSize = CGSizeMake(2*scrollView.frame.size.width, scrollView.frame.size.height);
[scrollView scrollRectToVisible:newFrame animated:YES];
button.frame = newFrame;
}
Here I change my contentSize of scrollView as it is very narrow to test that the scrollView is scrolling or not you don't need that line of code.
And when I drag the button left the scrollView is also automatically scrolled to the button frame to show the whole button try to implement this using UIView and if not possible just put one transparant UIButton on your view fully covered the view and you it to do the drag :)
I have a scrollview with an image as a subview. I would like to set the boundaries of the scrollview to be the size of the image view, so that you wouldn't be able to see any of the background.
I don't want this happening anymore.
The weird part is, that after you zoom in or out on the image, then the boundaries seem to fix themselves, and you can no longer move the image out of the way and see the background.
This is what I have going for code:
-(UIView *) viewForZoomingInScrollView:(UIScrollView *)scrollView
{
// return which subview we want to zoom
return self.imageView;
}
-(void)viewDidLoad{
[super viewDidLoad];
[self sendLogMessage:#"Second View Controller Loaded"];
//sets the initial view to scale to fit the screen
self.imageView.frame = CGRectMake(0, 0, CGRectGetWidth(self.view.bounds), CGRectGetHeight(self.view.bounds));
//sets the content size to be the size our our whole frame
self.scrollView.contentSize = self.imageView.image.size;
//setes the scrollview's delegate to itself
self.scrollView.delegate = self;
//sets the maximum zoom to 2.0, meaning that the picture can only become a maximum of twice as big
[self.scrollView setMaximumZoomScale : 2.5];
//sets the minimum zoom to 1.0 so that the scrollview can never be smaller than the image (no matter how far in/out we're zoomed)
[self.scrollView setMinimumZoomScale : 1.0];
[imageView addSubview:button];
}
I thought that this line would solve my problem
//sets the content size to be the size our our whole frame
self.scrollView.contentSize = self.imageView.image.size;
But like I said, it only works after I zoom in or out.
EDIT: When I switch
self.scrollView.contentSize = self.imageView.image.size;
to
self.scrollView.frame = self.imageView.frame;
It works like I want it to (you can't see the background), except the toolbar on the top is covered by the image.
imageView.image.size isn't necessarily the frame of the imageView itself, try setting the
scrollview.frame = imageView.frame
and then
scrollView.contentSize = imageView.image.size
Then you won't see any border. If you want the image to be the maximum size to start with,
do
imageView.frame = image.size;
[imageView setImage:image];
scrollView.frame = self.view.frame; //or desired size
[scrollView addSubView:imageView];
[scrollView setContentSize:image.size]; //or imageView.frame.size
To fix this, I ended up declaring a new CGRect , setting its origin to my scrollView's origin, setting its size with the bounds of my view, and then assigning this CGRect back to my scrollview frame
CGRect scrollFrame;
scrollFrame.origin = self.scrollView.frame.origin;
scrollFrame.size = CGSizeMake(CGRectGetWidth(self.view.bounds), CGRectGetHeight(self.view.bounds));
self.scrollView.frame = scrollFrame;
In the app I am working on, my goal right now is to scroll content when the keyboard shows and to allow users to scroll while it is showing. I have tried a few different solutions and none have been able to achieve this yet.
I'm using storyboards in the app and here is the element hierarchy within the view controller:
View Controller
UIScrollView
UIView
Buttons/textfields/labels/UIPickerView
I first set the UIScrollView's content size to be the same size of the view that was inside of it holding all of the form elements. When that didn't work, I tried over-exagerating the height of the content manually setting the content size to be 320 x 2000. Again, that didn't work. I have user interaction enabled set to YES on the scroll view as well. This is the code I have in there at this point.
CGSize contentSize = CGSizeMake(320, 2000);
[self.scrollView setContentSize:contentSize];
Within the scroll view I had a button that sits behind the whole form that has an action to close the keyboard if a user touches outside of it. I disabled that to see if it may have been a conflict in events that would keep it from scrolling. Again, didn't work.
-(IBAction)closeKeyboard:(id)sender
{
if(![self isFirstResponder]){
[self.view endEditing:YES];
}
}
I even set up some observers to see if the keyboard is about to appear or disappear. The observers would adjust the height of the scroll view, not the content size, just the scroll view itself, based on where the keyboard was currently sitting. So at this point, the content in the scroll view would be much taller than the scroll view itself, but still no scrolling is happening.
Here is the code for my observers:
// adjust view based on keyboard
- (void)keyboardWillHide:(NSNotification *)n
{
NSDictionary* userInfo = [n userInfo];
// get the size of the keyboard
CGSize keyboardSize = [[userInfo objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;
// resize the scrollview
CGRect viewFrame = self.view.frame;
// I'm also subtracting a constant kTabBarHeight because my UIScrollView was offset by the UITabBar so really only the portion of the keyboard that is leftover pass the UITabBar is obscuring my UIScrollView.
//viewFrame.size.height += keyboardSize.height;
CGRect scrollRect = CGRectMake(viewFrame.origin.x, viewFrame.origin.y, viewFrame.size.width, viewFrame.size.height + keyboardSize.height + 100);
[UIScrollView beginAnimations:nil context:NULL];
[UIScrollView setAnimationBeginsFromCurrentState:YES];
[UIScrollView setAnimationDuration:0.3];
[self.scrollView setFrame:scrollRect];
self.scrollView.userInteractionEnabled = YES;
[UIScrollView commitAnimations];
keyboardShowing = false;
}
- (void)keyboardWillShow:(NSNotification *)n
{
// This is an ivar I'm using to ensure that we do not do the frame size adjustment on the UIScrollView if the keyboard is already shown. This can happen if the user, after fixing editing a UITextField, scrolls the resized UIScrollView to another UITextField and attempts to edit the next UITextField. If we were to resize the UIScrollView again, it would be disastrous. NOTE: The keyboard notification will fire even when the keyboard is already shown.
if (keyboardShowing) {
return;
}
NSDictionary* userInfo = [n userInfo];
// get the size of the keyboard
CGSize keyboardSize = [[userInfo objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;
// resize the noteView
CGRect viewFrame = self.view.frame;
// I'm also subtracting a constant kTabBarHeight because my UIScrollView was offset by the UITabBar so really only the portion of the keyboard that is leftover pass the UITabBar is obscuring my UIScrollView.
CGRect scrollRect = CGRectMake(viewFrame.origin.x, viewFrame.origin.y, viewFrame.size.width, viewFrame.size.height - keyboardSize.height - 100);
//scrollView.frame.size.height -= keyboardSize.height;
//viewFrame.size.height -= keyboardSize.height;
[UIScrollView beginAnimations:nil context:NULL];
[UIScrollView setAnimationBeginsFromCurrentState:YES];
[UIScrollView setAnimationDuration:0.3];
[self.scrollView setFrame:scrollRect];
self.scrollView.userInteractionEnabled = YES;
[UIScrollView commitAnimations];
keyboardShowing = YES;
}
I would not be surprised if this is one of those simple mistakes that keeps slipping my mind, but this sort of accessibility feature would be really nice to have in the app. Any help would be much appreciated, or even other possible solutions to the problem I am trying to solve would be great too.
It looks like you're using a gesture recognizer in IB to detect a tap outside event. Because this recognizer is in the highest view in the hierarchy, it overrides the scrollview's detectors. You might need to change it slightly depending on which areas you want to be able to tap on to close the keyboard.
This is the UIResponder class reference. It lists all of the UIResponder events that your view controller automatically inherits. What might fix your problem is subclassing your UIScrollView and adding the keyboard closing code to it. Also, make sure that you set it to the first responder.
Final code that worked:
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
mouseSwiped = NO;
UITouch *touch = [touches anyObject];
if ([touch tapcount] == 1)
for(UIView *view in self.view.subviews){
if([view isKindOfClass:[UITextField class]]){
[view resignFirstResponder];
}
}
}
}