How to integrate the pinch zoom and zoom out in our apps, i am using imageview on scrollView
and my code is:
- (IBAction)handlePinchGesture:(UIGestureRecognizer *) recognizer {
if(zoomEnable == TRUE)
{
CGFloat factor = [(UIPinchGestureRecognizer *) recognizer scale];
CGFloat lastScaleFactor = 1;
//if the current factor is greater 1 --> zoom in
if (factor > 1) {
scrollView.transform = CGAffineTransformMakeScale(lastScaleFactor + (factor-1),lastScaleFactor + (factor-1));
scrollView.scrollEnabled = YES;
} else {
[UIView beginAnimations:#"animation" context:nil];
[UIView setAnimationDuration:0.5];
[UIView setAnimationTransition:UIViewAnimationTransitionNone forView:scrollView cache:NO];
scrollView.transform = CGAffineTransformMakeScale(1,1);
[UIView commitAnimations];
}
isScrollable = TRUE;
}
}
Its start zooming every time from start i want if i zoom some then again it start when i stop zoom. Any help is highly Appreciated
Thanks;
You don't need to use UIGestureRecognizers, if you're using UIScrollView already. UIScrollView supports pinch to zoom.
For zooming and panning to work, the delegate must implement both viewForZoomingInScrollView: and scrollViewDidEndZooming:withView:atScale:; in addition, the maximum (maximumZoomScale) and minimum (minimumZoomScale) zoom scale must be different.
-(void)zoomingImages{
self.FullSizeScrollView.pagingEnabled =YES;
NSMutableArray *_scrollArray =[[NSMutableArray alloc]init];
// add images to scroll array
[_scrollArray addObject:self.image1];
[_scrollArray addObject:self.image2];
//now call init with frame function given below to set frame for each image in scroll view
for(int i =0 ;i<[_scrollArray count];i++){
ZoomingImageView *_imageScrollView = [[ZoomingImageView alloc]initWithFrame:CGRectMake(i*320, 0, 320, 460)];
_imageScrollView.captureView=self;
[self.checkFullSizeScrollView addSubview:_imageScrollView];
[_imageScrollView release];
self.checkFullSizeScrollView.contentSize = CGSizeMake((i*320)+320, 460);
}
[_scrollArray release];
}
#implementation ZoomingImageView
- (id)initWithFrame:(CGRect)frame{
self = [super initWithFrame:frame];
if (self) {
self.maximumZoomScale = 4;
self.minimumZoomScale = 1;
self.userInteractionEnabled = YES;
self.multipleTouchEnabled = YES;
self.delegate = self;
self.bouncesZoom = NO;
self.currentImageView.clipsToBounds=NO;
self.contentMode =UIViewContentModeScaleAspectFit;
UIImageView *zoomImageView_ =[[UIImageView alloc]initWithFrame:CGRectMake(0, 0, frame.size.width, frame.size.height)];
self.currentImageView = zoomImageView_;
[zoomImageView_ release];
self.currentImageView.contentMode =UIViewContentModeScaleAspectFit;
self.currentImageView.userInteractionEnabled = YES;
self.currentImageView.multipleTouchEnabled = YES;
[self addSubview:self.currentImageView];}
return self;}
Related
I am using CoreText to draw text in multiple columns (depending on the orientation of the iPad).
To test, I've created an NSMutableString composed of the numbers 100 - 999. This text spans 5 columns, 1 or 2 of which are onscreen (depending on the orientation).
To my main ViewController I've added a custom UIScrollView to hold this text, and I want it to be scrollable.
I've noticed that the scrollview doesn't scroll until I set:
[myScrollView setContentMode:UIViewContentModeRedraw];
I do want the scrollView to call drawRect when the iPad is rotated (to adjust the number of columns)!
My issue with this though is that it seems to call drawRect over and over and over ... while scrolling (and thus allocates more and more memory, also causing some lag).
I add the UIScrollView to my main viewController like so:
myScrollView = [[CoreTextTestUIView alloc] init];
myScrollView.parentView = self;
if(FACING == #"PU" || FACING == #"PD")
{
myScrollView.frame = CGRectMake(0,50,768,974);
}
else
{
myScrollView.frame = CGRectMake(0,50,1024,718);
}
[myScrollView setContentMode:UIViewContentModeRedraw];
[container addSubview:myScrollView];
Again, I want drawRect to be called when the iPad is rotated, so the number of columns can change ... BUT I do not want it to call drawRect when I simply try to scroll the UIScrollView.
Can someone help me please?
...
below is the .m for my UIScrollView:
#import "CoreTextTestUIView.h"
#import <CoreText/CoreText.h>
#implementation CoreTextTestUIView
#synthesize parentView;
NSMutableString *testText;
-(id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if(self)
{
// Initialization code
//set BG color
self.backgroundColor = [[UIColor alloc] initWithRed:134 green:166 blue:228 alpha:1.0];
//UIScrollView Stuff
//self.delegate = self;
self.scrollEnabled = YES;
self.pagingEnabled = YES;
self.userInteractionEnabled = YES;
[self becomeFirstResponder];
self.showsVerticalScrollIndicator = NO;
self.showsHorizontalScrollIndicator = NO;
self.bounces = NO;
self.alwaysBounceHorizontal = YES;
self.alwaysBounceVertical = NO;
//generate long text
testText = [[NSMutableString alloc] initWithString:#""];
for(int i = 100; i < 1000; i++)
{
[testText appendString:[NSString stringWithFormat:#"%i ",i]];
}
self.alpha = 0.0;
[self fadeIn];
}
return self;
}
-(void)fadeIn
{
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:1.0];
[UIView setAnimationDelegate:self];
//[UIView setAnimationDidStopSelector:#selector(animationFinished:finished:context:)];
self.alpha = 1.0;
[UIView commitAnimations];
}
// Only override drawRect: if you perform custom drawing.
// An empty implementation adversely affects performance during animation.
-(void)drawRect:(CGRect)rect
{
NSMutableAttributedString *string = [[NSMutableAttributedString alloc] initWithString:[NSString stringWithFormat:#"%#",testText]];
//set font
CTFontRef helvetica = CTFontCreateWithName(CFSTR("Helvetica"), 40.0, NULL);
[string addAttribute:(id)kCTFontAttributeName
value:(id)helvetica
range:NSMakeRange(0, [string length])];
//layout master
CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString((CFAttributedStringRef)string);
//flip the coordinate system
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetTextMatrix(context, CGAffineTransformIdentity);
CGContextTranslateCTM(context, 0, self.bounds.size.height);
CGContextScaleCTM(context, 1.0, -1.0);
int textPos = 0;
int columnIndex = 0;
//how many columns? (orientation dependent)
float howManyColumns;
if(parentView.FACING == #"PU" || parentView.FACING == #"PD")
{
howManyColumns = 1.0;
}
else
{
howManyColumns = 2.0;
}
//create columns in loop
while(textPos < [string length])
{
NSLog(#"column started");
//column form
CGMutablePathRef columnPath = CGPathCreateMutable();
CGPathAddRect(columnPath, NULL,
CGRectMake((self.bounds.size.width/howManyColumns*columnIndex), 0,
(self.bounds.size.width/howManyColumns),
self.bounds.size.height));
//column frame
CTFrameRef columnFrame = CTFramesetterCreateFrame(framesetter,
CFRangeMake(textPos, 0),
columnPath,
NULL);
//use the column path
CTFrameRef frame = CTFramesetterCreateFrame(framesetter, CFRangeMake(textPos, 0), columnPath, NULL);
CFRange frameRange = CTFrameGetVisibleStringRange(frame);
//draw
CTFrameDraw(columnFrame, context);
//cleanup
CFRelease(columnFrame);
CGPathRelease(columnPath);
textPos += frameRange.length;
columnIndex++;
}
//set scrollView content size
int totalPages = (columnIndex+1)/howManyColumns;
self.contentSize = CGSizeMake(totalPages*self.bounds.size.width, self.frame.size.height);
//release
CFRelease(framesetter);
[string release];
}
-(void)dealloc
{
[super dealloc];
[parentView release];
[testText release];
}
#end
Looking at this, I can't see where you are setting the contentSize of your scrollView. If you do not set the contentSize of your scrollView, scrolling will not be enabled, and you will only see what fits within the current area of the scrollView. Also, if your text is static in a configuration, consider optimizing out some of the redrawing that is occurring and add it to a subview of the scrollView.
That is how drawRect works. It is called every single time that the view moves or changes or has something overlapping it. If you are managing memory correctly this shouldn't be a problem.
I have 5 pictures inside an infinite scrollView.
So in order to make that scrollView infinite/circular I positioned my images like this:
5 1 2 3 4 5 1
meaning: last picture first picture second picture.....last picture first picture
And in order for it to become infinite I have the following code:
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
{
if(self.scrollView.contentOffset.x == 0){
[self.scrollView scrollRectToVisible:CGRectMake(self.view.frame.size.width*pathImages.count, 0, self.view.frame.size.width, self.view.frame.size.height) animated:NO];
}
else if (self.scrollView.contentOffset.x == self.view.frame.size.width*(pathImages.count+1)) {
[self.scrollView scrollRectToVisible:CGRectMake(self.view.frame.size.width,0 ,self.view.frame.size.width, self.view.frame.size.height) animated:NO];
}
}
which means that when I'm at the last picture the contentOffset of the scrollView is set to go to the first picture-in this way I get an infinite scrollView.
What I wanted next was for my scrollView to slide automatically-for this I set a timer which calls one method-onTimer:
- (void) onTimer{
NSLog(#"flip pages");
if(h < pathImages.count*self.view.frame.size.width)
{
h+= self.view.frame.size.width;
}
else
{
h=self.view.frame.size.width;
}
if(self.scrollView.contentOffset.x == 0){
[self.scrollView scrollRectToVisible:CGRectMake(self.view.frame.size.width*pathImages.count, 0, self.view.frame.size.width, self.view.frame.size.height) animated:NO];
}
if (self.scrollView.contentOffset.x == self.view.frame.size.width*pathImages.count)
{
[self.scrollView scrollRectToVisible:CGRectMake(self.view.frame.size.width,0 ,self.view.frame.size.width, self.view.frame.size.height) animated:NO];
}
else
[UIView animateWithDuration:1
delay:0
options:UIViewAnimationOptionCurveEaseInOut
animations:^{ self.scrollView.contentOffset = CGPointMake(h, 0); }
completion:NULL];
}
This magic line:
[UIView animateWithDuration:1
delay:0
options:UIViewAnimationOptionCurveEaseInOut
animations:^{ self.scrollView.contentOffset = CGPointMake(h, 0); }
completion:NULL];
does the scoll automatically with animation.
Everything is great except this:
after I view the last picture I should set the offset of scroll view in order to get back to the first picture with animation.
Well if I do that:
if (self.scrollView.contentOffset.x == self.view.frame.size.width*pathImages.count)
{
[UIView animateWithDuration:1
delay:0
options:UIViewAnimationOptionCurveEaseInOut
animations:^{ [self.scrollView scrollRectToVisible:CGRectMake(self.view.frame.size.width,0 ,self.view.frame.size.width, self.view.frame.size.height) animated:NO]; }
completion:NULL];
}
after the last picture is viewed in order to get to the first picture...it loops through all the other pictures.
What I want is this:after I view the last picture to get me back to the first picture which should be loaded on screen using animation, but without viewing all the other pictures between them.Thanks
If I see this correctly, the problem is, that you again use the animation to scroll the view back to zero position. I believe you need to modify the last bit of code you posted to something like this:
if (self.scrollView.contentOffset.x == self.view.frame.size.width*pathImages.count)
{
[self.scrollView scrollRectToVisible:CGRectMake(self.view.frame.size.width,0 ,self.view.frame.size.width, self.view.frame.size.height) animated:NO];//no animation on returning
[self onTimer];//even if this code is already inside method "onTimer"
}
Rather then what you are doing try using a scrollview that displays only 3 to 5 images at the time (if they are fullscreen). If you will have many images in your application, it will crash because of high memory consumption. Try playing with this test example that does nearly what you want:
HEADER:
#import <Foundation/Foundation.h>
#interface IScrollView : UIScrollView <UIScrollViewDelegate> {
NSMutableArray *imagePaths;
UIImageView *imageViews[3];
NSInteger currentImage;
NSTimer *animationTimer;//weak link
}
#end
SOURCE:
#import "IScrollView.h"
#implementation IScrollView
- (UIImage *)imageFromResourcesWithName:(NSString *)name {
UIImage *ret = [[UIImage alloc] initWithContentsOfFile:[[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:name]];
return [ret autorelease];
}
- (id)initWithFrame:(CGRect)frame {
if((self = [super initWithFrame:frame])) {
imagePaths = [[NSMutableArray alloc] init];
[imagePaths addObject:#"imag1.png"];
[imagePaths addObject:#"imag2.png"];
[imagePaths addObject:#"imag3.png"];
[imagePaths addObject:#"imag4.png"];
[imagePaths addObject:#"imag5.png"];
imageViews[0] = [[UIImageView alloc] initWithFrame:CGRectMake(320.0f*0, .0f, 320.0f, 480.0f)];
imageViews[1] = [[UIImageView alloc] initWithFrame:CGRectMake(320.0f*1, .0f, 320.0f, 480.0f)];
imageViews[2] = [[UIImageView alloc] initWithFrame:CGRectMake(320.0f*2, .0f, 320.0f, 480.0f)];
[self addSubview:imageViews[0]];
[self addSubview:imageViews[1]];
[self addSubview:imageViews[2]];
imageViews[0].image = [self imageFromResourcesWithName:[imagePaths objectAtIndex:0]];
imageViews[1].image = [self imageFromResourcesWithName:[imagePaths objectAtIndex:1]];
imageViews[2].image = [self imageFromResourcesWithName:[imagePaths objectAtIndex:2]];
currentImage = 1;
self.contentOffset = CGPointMake(320.0f*currentImage, .0f);
self.contentSize = CGSizeMake(3.0f*320.0f, 480.0f);
self.delegate = self;
animationTimer = [NSTimer scheduledTimerWithTimeInterval:1.0/60.0 target:self selector:#selector(scrollFragment) userInfo:nil repeats:YES];
}
return self;
}
- (void)repositionIfNeeded {
CGFloat offsetX = self.contentOffset.x;
NSInteger iCount = [imagePaths count];
if(offsetX > 320.0f*1.75f) {
self.contentOffset = CGPointMake(offsetX-320.0f, .0f);
imageViews[0].image = imageViews[1].image;
imageViews[1].image = imageViews[2].image;
NSInteger imageToLoad = currentImage+2;
if(imageToLoad>iCount-1)
imageToLoad -= iCount;
imageViews[2].image = [self imageFromResourcesWithName:[imagePaths objectAtIndex:imageToLoad]];
currentImage++;
if(currentImage>iCount-1)
currentImage -= iCount;
}
else if(offsetX < 320.0f*.25f) {
self.contentOffset = CGPointMake(offsetX+320.0f, .0f);
imageViews[2].image = imageViews[1].image;
imageViews[1].image = imageViews[0].image;
NSInteger imageToLoad = currentImage-2;
if(imageToLoad<0)
imageToLoad += iCount;
imageViews[0].image = [self imageFromResourcesWithName:[imagePaths objectAtIndex:imageToLoad]];
currentImage--;
if(currentImage<0)
currentImage += iCount;
}
}
- (void)scrollFragment {
self.contentOffset = CGPointMake(self.contentOffset.x+1.0, .0f);
[self repositionIfNeeded];
}
- (void)scrollViewDidScroll:(UIScrollView *)scrollView {
[self repositionIfNeeded];
}
- (void)dealloc {
[imageViews[0] release];
[imageViews[1] release];
[imageViews[2] release];
[imagePaths release];
}
#end
So, I've managed to create a UIScrollView with zooming method programmatically, but I'm kind of stuck how to solve an issue I'm having with zooming:
When I zoom in or out the point at where it expands/retracts does not happen where I do the pinch gesture, it happens on a corner.
After zooming in or out, it will leave extra space outside the bounds, and I cannot scroll the image more than half the width & height of the image.
Other than this, I'm so close to getting it working 100%. I've tried playing around with achorpoints, but it looks like the scroll view and image view does not respond to this.
Here is the important stuff in the code listing:
UIScrollView *mapScrollView;
UIImageView *mapImageView;
CGFloat lastScale = 0;
NSMutableArray *map_List;
- (id)initWithFrame:(CGRect)frame {
self = [super initWithFrame:frame];
if (self) {
mainMenuAppDelegate *del = (mainMenuAppDelegate *)[[UIApplication sharedApplication] delegate];
map_List = [[NSMutableArray alloc] init];
[map_List addObject:#"Pacific_Map_8bit.png"];
[map_List addObject:#"Atlantic_Map_8bit.png"];
CGRect mapScrollViewFrame = CGRectMake(0, 0, 1024, 768);
mapScrollView = [[UIScrollView alloc] initWithFrame:mapScrollViewFrame];
mapScrollView.contentSize = CGSizeMake(2437, 1536);
UIImage *mapImage = [UIImage imageNamed:[map_List objectAtIndex:mapNum]];
mapImageView = [[UIImageView alloc] initWithImage: mapImage];
mapScrollView.bounces = NO;
[mapImage release];
[mapScrollView addSubview:mapImageView];
[self addSubview:mapScrollView];
mapImageView.userInteractionEnabled = YES;
UIPinchGestureRecognizer *pinchRecognizer = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:#selector(scale:)];
[mapImageView addGestureRecognizer:pinchRecognizer];
[pinchRecognizer release];
}
return self;
}
// the scale method thats triggered to zoom when pinching
-(void)scale:(id)sender {
if([(UIPinchGestureRecognizer*)sender state] == UIGestureRecognizerStateEnded) {
lastScale = 1.0;
return;
}
CGFloat scale = 1.0 - (lastScale - [(UIPinchGestureRecognizer*)sender scale]);
NSLog(#"map scale %f", scale);
CGFloat mapWidth = mapImageView.frame.size.width;
CGFloat mapHeight = mapImageView.frame.size.height;
NSLog(#"map width %f", mapWidth);
if(scale>=1 & mapWidth<=4000 || scale<1 & mapWidth>=1234){
CGAffineTransform currentTransform = [(UIPinchGestureRecognizer*)sender view].transform;
CGAffineTransform newTransform = CGAffineTransformScale(currentTransform, scale, scale);
[[(UIPinchGestureRecognizer*)sender view] setTransform:newTransform];
lastScale = [(UIPinchGestureRecognizer*)sender scale];
}
mapScrollView.contentSize = CGSizeMake(mapWidth, mapHeight);
}
Thanks!
UIScrollView has built-in zooming support. All you need to do is set the minimumZoomScale and maximumZoomScale properties, and return a view to be used for zooming using viewForZoomingInScrollView.
I have a UITextView sitting on top of a UIView, and if I tap on it to open it for editing, then the keyboard is blocking the bottom of the view and I can not see it even though I can write in this area. Can I tell the UITextView to have a different scroll area or what is the solution?
A better solution, specially for iOS 7, would be to adjust the content inset property of the textview instead of its frame, this way, the keyboard will blur the text that falls behinds it like in any other iOS 7 app. You'll also have to adjust the scroll indicators to match.
Expanding Lindemann's answer,
- (void)keyboardWasShown:(NSNotification*)notification {
NSDictionary* info = [notification userInfo];
CGSize keyboardSize = [[info objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size;
self.textView.contentInset = UIEdgeInsetsMake(0, 0, keyboardSize.height, 0);
self.textView.scrollIndicatorInsets = self.textView.contentInset;
}
- (void)keyboardWillBeHidden:(NSNotification*)notification {
self.textView.contentInset = UIEdgeInsetsZero;
self.textView.scrollIndicatorInsets = UIEdgeInsetsZero;
}
An easy solution is to implement the UITextViewDelegate Methods
- (void)textViewDidBeginEditing:(UITextView *)textView
and
- (void)textViewDidEndEditing:(UITextView *)textView
You can make the UITextView Frame smaller when the keyboard appears and make it full size again when the keyboard disappears...like this:
- (void)textViewDidBeginEditing:(UITextView *)textView {
self.textView.frame = CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height/1.8);
}
- (void)textViewDidEndEditing:(UITextView *)textView {
self.textView.frame = CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height);
}
EDIT
The solution above is bad...don't use it!!!
Now I think it's a better idea to resize the UITextView in proportion to the keyboard size and not with a fixed value...because the size of the keyboard can change when an other language become chosen or the device become rotated...of course -.-
At first you must register your UIViewController which displays your UITextView for receiving Keyboard Notifications:
- (void)viewDidLoad {
[super viewDidLoad];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(keyboardWasShown:)
name:UIKeyboardDidShowNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(keyboardWillBeHidden:)
name:UIKeyboardWillHideNotification object:nil];
}
Then you have to implement the two methods -keyboardWasShown: and
-keyboardWillBeHidden:.
The size of the actual keyboard is contained in the NSNotification object.
- (void)keyboardWasShown:(NSNotification*)notification {
NSDictionary* info = [notification userInfo];
CGSize keyboardSize = [[info objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size;
self.textView.frame = CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height - keyboardSize.height);
}
- (void)keyboardWillBeHidden:(NSNotification*)notification {
self.textView.frame = CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height);
}
If you want a Messages App style input, you can use a nested UITextView (allows for multiple lines of text). It will look like this in the end:
You start by laying out a view to hold all the child views. Here the background colour of the bottomView is set to match UIKeyboardAppearanceDark. It rests at the bottom of the screen.
bottomView = [UIView new];
bottomView.frame = CGRectMake(0, h-45, w, 45);
bottomView.backgroundColor = [UIColor colorWithRed:0.078 green:0.078 blue:0.078 alpha:1];
[self.view addSubview:bottomView];
Then, add in a simple background view styled like a typical UITextField, and add the UITextView as a subview to that. The inputTV (UITextView) takes its height based upon the size of the font. Also, all the padding is removed from inputTV using the textContainer variables.
inputTVBG = [UIImageView new];
inputTVBG.frame = CGRectMake(10, 8, w-90, 29);
inputTVBG.backgroundColor = [[UIColor whiteColor] colorWithAlphaComponent:0.1f];
inputTVBG.layer.cornerRadius = 4.0f;
inputTVBG.userInteractionEnabled = true;
inputTVBG.clipsToBounds = true;
[bottomView addSubview:inputTVBG];
inputTV = [UITextView new];
inputTV.font = [UIFont systemFontOfSize:14.0f];
inputTV.frame = CGRectMake(5, 6, w-100, inputTV.font.lineHeight);
inputTV.backgroundColor = [UIColor clearColor];
inputTV.keyboardAppearance = UIKeyboardAppearanceDark;
inputTV.delegate = self;
inputTV.autocorrectionType = UITextAutocorrectionTypeNo;
inputTV.tintColor = [UIColor whiteColor];
inputTV.textColor = [UIColor whiteColor];
inputTV.textContainer.lineFragmentPadding = 0;
inputTV.textContainerInset = UIEdgeInsetsZero;
[inputTVBG addSubview:inputTV];
In the example above, I've included a label indicating how many letters are left (max / min characters) and a submit button.
lettersLeftLabel = [UILabel new];
lettersLeftLabel.frame = CGRectMake(w-70, 8, 60, 16);
lettersLeftLabel.font = [UIFont systemFontOfSize:12.0f];
lettersLeftLabel.textColor = [[UIColor whiteColor] colorWithAlphaComponent:0.5f];
lettersLeftLabel.alpha = 0.0f;
[bottomView addSubview:lettersLeftLabel];
submitButton = [UIButton new];
submitButton.frame = CGRectMake(w-70, 0, 60, 45);
[submitButton setTitle:#"SUBMIT" forState:UIControlStateNormal];
[submitButton setTitleColor:[_peacock.applePink colorWithAlphaComponent:0.5f] forState:UIControlStateNormal];
[submitButton addTarget:self action:#selector(submit) forControlEvents:UIControlEventTouchUpInside];
[submitButton.titleLabel setFont:[UIFont boldSystemFontOfSize:14.0f]];
[bottomView addSubview:submitButton];
Add this line early on in your code, so you get keyboard change updates:
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];
It calls the method below when a user clicks on the inputTV. Here it sets the variable 'keyboardHeight' used later on.
-(void)keyboardWillShow:(NSNotification *)n {
CGRect rect = [n.userInfo[UIKeyboardFrameEndUserInfoKey] CGRectValue];
CGRect keyboardFrame = [self.view convertRect:rect fromView:nil];
keyboardHeight = keyboardFrame.size.height;
[self textViewDidChange:inputTV];
}
This is the main bit of code that takes care of all the movement and resizing of the inputTV.
-(void)textViewDidChange:(UITextView *)textView {
//1. letters and submit button vars
int numberOfCharacters = (int)textView.text.length;
int minCharacters = 50;
int maxCharacters = 400;
int remainingCharacters = maxCharacters-numberOfCharacters;
//2. if entered letters exceeds maximum, reset text and return
if (remainingCharacters <= 0){
textView.text = [textView.text substringToIndex:maxCharacters];
numberOfCharacters = maxCharacters;
}
//3. set height vars
inputTV.scrollEnabled = true;
float textHeight = textView.contentSize.height;
float lineHeight = roundf(textView.font.lineHeight);
float additionalHeight = textHeight - lineHeight;
float moveUpHeight = keyboardHeight + additionalHeight;
//4. default letter colour is weak white
UIColor * letterColour = [[UIColor whiteColor] colorWithAlphaComponent:0.5f];
if (numberOfCharacters < minCharacters){ //minimum threshold not met
lettersLeftLabel.text = [NSString stringWithFormat:#"%i", minCharacters-numberOfCharacters];
letterColour = [_peacock.applePink colorWithAlphaComponent:0.5f];
} else { //within range
lettersLeftLabel.text = [NSString stringWithFormat:#"%i/%i", numberOfCharacters, maxCharacters];
if (remainingCharacters<5){ //increase alpha towards the end of range
letterColour = [[UIColor whiteColor] colorWithAlphaComponent:1.0f - ((float)remainingCharacters/10)];
}
}
//5. hide/show letter label based on textView height
float letterAlpha = 0.0f; //default hide
if (additionalHeight > 0){ letterAlpha = 1.0f; } //if multiline, show
[UIView animateWithDuration:0.3f
delay:0.0f
options:UIViewAnimationOptionCurveEaseOut
animations:^{
lettersLeftLabel.alpha = letterAlpha;
lettersLeftLabel.textColor = letterColour;
}
completion:^(BOOL finished){
}];
//6. update submit colour based on minimum threshold
UIColor * submitColour = [_peacock.applePink colorWithAlphaComponent:0.5f];
bool enableSubmit = false;
if (numberOfCharacters >= minCharacters){
submitColour = _peacock.applePink;
enableSubmit = true;
}
[submitButton setEnabled:enableSubmit];
[UIView animateWithDuration:0.3f
delay:0.0f
options:UIViewAnimationOptionCurveEaseOut
animations:^{
[submitButton setTitleColor:submitColour forState:UIControlStateNormal];
}
completion:^(BOOL finished){
}];
//7. special case if you want to limit the frame size of the input TV to a specific number of lines
bool shouldEnableScroll = false;
int maxNumberOfLines = 5; //anything above this triggers the input TV to stay stationary and update its scroll
int actualNumberOfLines = textHeight / textView.font.lineHeight;
if (actualNumberOfLines >= maxNumberOfLines){ //recalculate vars for frames
textHeight = maxNumberOfLines * lineHeight;
additionalHeight = textHeight - lineHeight;
moveUpHeight = keyboardHeight + additionalHeight;
shouldEnableScroll = true;
}
//8. adjust frames of views
inputTV.frame = CGRectMake(5, 6, w-100, textHeight); //update immediately (parent view clips to bounds)
[UIView animateWithDuration:0.3f
delay:0.0f
options:UIViewAnimationOptionCurveEaseOut
animations:^{
bottomView.frame = CGRectMake(0, h-45-moveUpHeight, w, 45+additionalHeight);
inputTVBG.frame = CGRectMake(10, 8, w-90, lineHeight+additionalHeight+13);
submitButton.frame = CGRectMake(w-70, additionalHeight, 60, 45);
}
completion:^(BOOL finished){
inputTV.scrollEnabled = shouldEnableScroll; //default disable scroll here to avoid bouncing
}];
}
In the above method, this is what's happening:
If you want to set a minimum or maximum number of characters, you can do so here. You pull the the number of characters and store as an integer, and calculate how many characters are left.
If the user has reached the maximum number of characters, reset the textView text by stripping back to your max.
These vars are used to calculate how much you need to move your bottomView up and also for the resizing its subviews.
This method is just to change the colour / text of some UI elements. It's not strictly necessary.
This method brings the lettersLeftLabel onto view if you're using that. It's not necessary either.
This enables the submit button only if the minimum number of characters has been reached. It changes the colour as an indicator to the user.
If you want to limit the growth of the inputTV and surrounding elements, you can include this bit of code. It requires you to set the maximum number of lines you want to show. If the user exceeds the max, scroll is reenabled for the inputTV, otherwise it defaults to false (important to stop it bouncing).
This is the main resizing logic, moving the bottomView up and resizing its child views. The submit button needs to stay in the same position, so move it down as the bottomView grows.
NOTE: If you just want the barebones code, you only need to implement steps 3 and 8.
Apple has some code samples that deal with this exact situation.
I finally got it working. Here is my solution, can you guys spot any errors in my design?
#synthesize textView = _textView;
#synthesize callbackViewController = _callbackViewController;
-(void)keyboardWasShown:(NSNotification*)aNotification {
if(keyboardShown) {
return;
}
NSDictionary *info = [aNotification userInfo];
// Get the size of the keyboard.
NSValue *aValue = [info objectForKey:UIKeyboardFrameBeginUserInfoKey];
keyboardSize = [aValue CGRectValue].size;
// Resize the scroll view (which is the root view of the window)
CGRect viewFrame = [self.textView frame];
orientationAtShown = orientation;
if(orientation == UIInterfaceOrientationPortrait || orientation == UIInterfaceOrientationPortraitUpsideDown) {
viewFrame.size.height -= keyboardSize.height;
} else {
viewFrame.size.height -= keyboardSize.width;
}
self.textView.frame = viewFrame;
// Scroll the active text field into view.
//CGRect textFieldRect = [activeField frame];
[self.textView scrollRectToVisible:viewFrame animated:YES];
keyboardShown = YES;
}
-(void)keyboardWasHidden:(NSNotification*)aNotification {
if(!keyboardShown) {
return;
}
// Reset the height of the scroll view to its original value
CGRect viewFrame = [self.textView frame];
if(orientationAtShown == UIInterfaceOrientationPortrait || orientationAtShown == UIInterfaceOrientationPortraitUpsideDown) {
viewFrame.size.height += keyboardSize.height;
} else {
viewFrame.size.height += keyboardSize.width;
}
self.textView.frame = viewFrame;
keyboardShown = NO;
}
-(void)registerForKeyboardNotifications {
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(keyboardWasShown:)
name:UIKeyboardDidShowNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(keyboardWasHidden:)
name:UIKeyboardDidHideNotification object:nil];
}
-(void)viewWillAppear:(BOOL)animated {
keyboardShown = NO;
[self registerForKeyboardNotifications];
}
-(void)viewWillDisappear:(BOOL)animated {
[[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil];
}
// Override to allow orientations other than the default portrait orientation.
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
if(keyboardShown) {
[self keyboardWasHidden:nil];
}
orientation = interfaceOrientation;
CGRect viewFrame = [self.textView frame];
if(orientation == UIInterfaceOrientationPortrait || orientation == UIInterfaceOrientationPortraitUpsideDown) {
if(viewFrame.size.width > viewFrame.size.height) {
CGRect viewFrameFixed = CGRectMake(viewFrame.origin.x, viewFrame.origin.y, viewFrame.size.height, viewFrame.size.width);
self.textView.frame = viewFrameFixed;
}
} else {
if(viewFrame.size.width < viewFrame.size.height) {
CGRect viewFrameFixed = CGRectMake(viewFrame.origin.x, viewFrame.origin.y, viewFrame.size.height, viewFrame.size.width);
self.textView.frame = viewFrameFixed;
}
}
// Return YES for supported orientations
return YES;
}
#Alejandro above has the right idea, but his code does not work in landscape mode. I have amended his keyboardWasShown: method to work correctly in all orientations:
- (void)keyboardWasShown:(NSNotification *)notification {
if (self.textView != nil) {
NSDictionary* info = [notification userInfo];
CGRect keyboardRect = [self.textView convertRect:[[info objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue] fromView:nil];
CGSize keyboardSize = keyboardRect.size;
self.textView.contentInset = UIEdgeInsetsMake(0, 0, keyboardSize.height, 0);
self.textView.scrollIndicatorInsets = self.textView.contentInset;
}
}
Add Observer first in viewDidLoad.
- (void)viewDidLoad {
[super viewDidLoad];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(keyboardWasShown:)
name:UIKeyboardDidShowNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(keyboardWasHidden:)
name:UIKeyboardWillHideNotification object:nil];
}
Call the methods
- (void)keyboardWasShown:(NSNotification*)aNotification
{
NSDictionary* info = [aNotification userInfo];
CGSize kbSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;
UIEdgeInsets contentInsets = UIEdgeInsetsMake(0.0, 0.0, kbSize.height, 0.0);
self.textView.contentInset = contentInsets;
self.textView.scrollIndicatorInsets = contentInsets;
// If active text field is hidden by keyboard, scroll it so it's visible
// Your app might not need or want this behavior.
CGRect aRect = self.view.frame;
aRect.size.height -= kbSize.height;
if (!CGRectContainsPoint(aRect, self.textView.frame.origin) ) {
[self.textView scrollRectToVisible:self.textView.frame animated:YES];
}
}
// Called when the UIKeyboardWillHideNotification is sent
- (void)keyboardWasHidden:(NSNotification*)aNotification
{
UIEdgeInsets contentInsets = UIEdgeInsetsZero;
self.textView.contentInset = contentInsets;
self.textView.scrollIndicatorInsets = contentInsets;
}
if you have more then 1 textfield or you want to reduce your code then try this code
- (void)textFieldDidBeginEditing:(UITextField *)textField{
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.35f];
CGRect frame = self.view.frame;
frame.origin.y = (self.view.frame.size.height - textField.frame.origin.y) - self.view.frame.size.height+60;
if (frame.origin.y<-162) {
frame.origin.y = -162;
}
[self.view setFrame:frame];
[UIView commitAnimations];
}
-(BOOL)textFieldShouldEndEditing:(UITextField *)textField{
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.35f];
CGRect frame = self.view.frame;
frame.origin.y = 0;
[self.view setFrame:frame];
[UIView commitAnimations];
return YES;
}
Extending #alejandro & #Mani :
Th final answer:
- (void)keyboardWasShown:(NSNotification *)notification {
if (self.textView != nil) {
NSDictionary* info = [notification userInfo];
CGRect keyboardRect = [self.textNote convertRect:[[info objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue] fromView:nil];
CGSize keyboardSize = keyboardRect.size;
self.textView.contentInset = UIEdgeInsetsMake(0, 0, keyboardSize.height, 0);
self.textView.scrollIndicatorInsets = self.textView.contentInset;
}
}
- (void)keyboardWillBeHidden:(NSNotification*)notification {
self.textView.scrollIndicatorInsets = UIEdgeInsetsZero;
self.textView.scrollIndicatorInsets = UIEdgeInsetsZero;
}
I have been playing around with one of the iPhone examples from Apple' web site (ScrollViewSuite) . I am trying to tweak it a bit so that when I rotate the the iPad the image will fit into the screen in landscape mode vertical. I have been successful in getting the image to rotate, but the image is larger than the height of the landscape screen, so the bottom is below the screen. I would like to image to scale to the height of the landscape screen.
I have been playing around with various autoSizingMask attributes without success.
The imageView is called "zoomView" this is the actual image which loads into a scrollView called imageScrollView.
I am trying to achieve the screen to rotate and look like this.... sorry only 1 link allowed new user :(
olsonvox.com/photos/correct.png
However, this is what My screen is looking like.
http://www.olsonvox.com/photos/incorrect.png
I would really appreciate some advice or guidance. Below is the RootViewController.m for the project.
Blade
#
import "RootViewController.h"
#define ZOOM_VIEW_TAG 100
#define ZOOM_STEP 1.5
#define THUMB_HEIGHT 150
#define THUMB_V_PADDING 25
#define THUMB_H_PADDING 25
#define CREDIT_LABEL_HEIGHT 25
#define AUTOSCROLL_THRESHOLD 30
#interface RootViewController (ViewHandlingMethods)
- (void)toggleThumbView;
- (void)pickImageNamed:(NSString *)name;
- (NSArray *)imageNames;
- (void)createThumbScrollViewIfNecessary;
- (void)createSlideUpViewIfNecessary;
#end
#interface RootViewController (AutoscrollingMethods)
- (void)maybeAutoscrollForThumb:(ThumbImageView *)thumb;
- (void)autoscrollTimerFired:(NSTimer *)timer;
- (void)legalizeAutoscrollDistance;
- (float)autoscrollDistanceForProximityToEdge:(float)proximity;
#end
#interface RootViewController (UtilityMethods)
- (CGRect)zoomRectForScale:(float)scale withCenter:(CGPoint)center;
#end
#implementation RootViewController
- (void)loadView {
[super loadView];
imageScrollView = [[UIScrollView alloc] initWithFrame:[[self view]bounds]];
// this code makes the image resize to the width and height properly.
imageScrollView.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin| UIViewAutoresizingFlexibleBottomMargin| UIViewAutoresizingFlexibleBottomMargin;
// TRY SETTNG CENTER HERE SOMEHOW>....
[imageScrollView setBackgroundColor:[UIColor blackColor]];
[imageScrollView setDelegate:self];
[imageScrollView setBouncesZoom:YES];
[[self view] addSubview:imageScrollView];
[self toggleThumbView];
// intitializes with the first image.
[self pickImageNamed:#"lookbook1"];
}
- (void)dealloc {
[imageScrollView release];
[slideUpView release];
[thumbScrollView release];
[super dealloc];
}
#pragma mark UIScrollViewDelegate methods
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView {
UIView *view = nil;
if (scrollView == imageScrollView) {
view = [imageScrollView viewWithTag:ZOOM_VIEW_TAG];
}
return view;
}
/************************************** NOTE **************************************/
/* The following delegate method works around a known bug in zoomToRect:animated: */
/* In the next release after 3.0 this workaround will no longer be necessary */
/**********************************************************************************/
- (void)scrollViewDidEndZooming:(UIScrollView *)scrollView withView:(UIView *)view atScale:(float)scale {
[scrollView setZoomScale:scale+0.01 animated:NO];
[scrollView setZoomScale:scale animated:NO];
}
#pragma mark TapDetectingImageViewDelegate methods
- (void)tapDetectingImageView:(TapDetectingImageView *)view gotSingleTapAtPoint:(CGPoint)tapPoint {
// Single tap shows or hides drawer of thumbnails.
[self toggleThumbView];
}
- (void)tapDetectingImageView:(TapDetectingImageView *)view gotDoubleTapAtPoint:(CGPoint)tapPoint {
// double tap zooms in
float newScale = [imageScrollView zoomScale] * ZOOM_STEP;
CGRect zoomRect = [self zoomRectForScale:newScale withCenter:tapPoint];
[imageScrollView zoomToRect:zoomRect animated:YES];
}
- (void)tapDetectingImageView:(TapDetectingImageView *)view gotTwoFingerTapAtPoint:(CGPoint)tapPoint {
// two-finger tap zooms out
float newScale = [imageScrollView zoomScale] / ZOOM_STEP;
CGRect zoomRect = [self zoomRectForScale:newScale withCenter:tapPoint];
[imageScrollView zoomToRect:zoomRect animated:YES];
}
#pragma mark ThumbImageViewDelegate methods
- (void)thumbImageViewWasTapped:(ThumbImageView *)tiv {
[self pickImageNamed:[tiv imageName]];
[self toggleThumbView];
}
- (void)thumbImageViewStartedTracking:(ThumbImageView *)tiv {
[thumbScrollView bringSubviewToFront:tiv];
}
// CONTROLS DRAGGING AND DROPPING THUMBNAILS...
- (void)thumbImageViewMoved:(ThumbImageView *)draggingThumb {
// check if we've moved close enough to an edge to autoscroll, or far enough away to stop autoscrolling
[self maybeAutoscrollForThumb:draggingThumb];
/* The rest of this method handles the reordering of thumbnails in the thumbScrollView. See */
/* ThumbImageView.h and ThumbImageView.m for more information about how this works. */
// we'll reorder only if the thumb is overlapping the scroll view
if (CGRectIntersectsRect([draggingThumb frame], [thumbScrollView bounds])) {
BOOL draggingRight = [draggingThumb frame].origin.x > [draggingThumb home].origin.x ? YES : NO;
/* we're going to shift over all the thumbs who live between the home of the moving thumb */
/* and the current touch location. A thumb counts as living in this area if the midpoint */
/* of its home is contained in the area. */
NSMutableArray *thumbsToShift = [[NSMutableArray alloc] init];
// get the touch location in the coordinate system of the scroll view
CGPoint touchLocation = [draggingThumb convertPoint:[draggingThumb touchLocation] toView:thumbScrollView];
// calculate minimum and maximum boundaries of the affected area
float minX = draggingRight ? CGRectGetMaxX([draggingThumb home]) : touchLocation.x;
float maxX = draggingRight ? touchLocation.x : CGRectGetMinX([draggingThumb home]);
// iterate through thumbnails and see which ones need to move over
for (ThumbImageView *thumb in [thumbScrollView subviews]) {
// skip the thumb being dragged
if (thumb == draggingThumb) continue;
// skip non-thumb subviews of the scroll view (such as the scroll indicators)
if (! [thumb isMemberOfClass:[ThumbImageView class]]) continue;
float thumbMidpoint = CGRectGetMidX([thumb home]);
if (thumbMidpoint >= minX && thumbMidpoint <= maxX) {
[thumbsToShift addObject:thumb];
}
}
// shift over the other thumbs to make room for the dragging thumb. (if we're dragging right, they shift to the left)
float otherThumbShift = ([draggingThumb home].size.width + THUMB_H_PADDING) * (draggingRight ? -1 : 1);
// as we shift over the other thumbs, we'll calculate how much the dragging thumb's home is going to move
float draggingThumbShift = 0.0;
// send each of the shifting thumbs to its new home
for (ThumbImageView *otherThumb in thumbsToShift) {
CGRect home = [otherThumb home];
home.origin.x += otherThumbShift;
[otherThumb setHome:home];
[otherThumb goHome];
draggingThumbShift += ([otherThumb frame].size.width + THUMB_H_PADDING) * (draggingRight ? 1 : -1);
}
// change the home of the dragging thumb, but don't send it there because it's still being dragged
CGRect home = [draggingThumb home];
home.origin.x += draggingThumbShift;
[draggingThumb setHome:home];
}
}
- (void)thumbImageViewStoppedTracking:(ThumbImageView *)tiv {
// if the user lets go of the thumb image view, stop autoscrolling
[autoscrollTimer invalidate];
autoscrollTimer = nil;
}
#pragma mark Autoscrolling methods
- (void)maybeAutoscrollForThumb:(ThumbImageView *)thumb {
autoscrollDistance = 0;
// only autoscroll if the thumb is overlapping the thumbScrollView
if (CGRectIntersectsRect([thumb frame], [thumbScrollView bounds])) {
CGPoint touchLocation = [thumb convertPoint:[thumb touchLocation] toView:thumbScrollView];
float distanceFromLeftEdge = touchLocation.x - CGRectGetMinX([thumbScrollView bounds]);
float distanceFromRightEdge = CGRectGetMaxX([thumbScrollView bounds]) - touchLocation.x;
if (distanceFromLeftEdge < AUTOSCROLL_THRESHOLD) {
autoscrollDistance = [self autoscrollDistanceForProximityToEdge:distanceFromLeftEdge] * -1; // if scrolling left, distance is negative
} else if (distanceFromRightEdge < AUTOSCROLL_THRESHOLD) {
autoscrollDistance = [self autoscrollDistanceForProximityToEdge:distanceFromRightEdge];
}
}
// if no autoscrolling, stop and clear timer
if (autoscrollDistance == 0) {
[autoscrollTimer invalidate];
autoscrollTimer = nil;
}
// otherwise create and start timer (if we don't already have a timer going)
else if (autoscrollTimer == nil) {
autoscrollTimer = [NSTimer scheduledTimerWithTimeInterval:(1.0 / 60.0)
target:self
selector:#selector(autoscrollTimerFired:)
userInfo:thumb
repeats:YES];
}
}
- (float)autoscrollDistanceForProximityToEdge:(float)proximity {
// the scroll distance grows as the proximity to the edge decreases, so that moving the thumb
// further over results in faster scrolling.
return ceilf((AUTOSCROLL_THRESHOLD - proximity) / 5.0);
}
- (void)legalizeAutoscrollDistance {
// makes sure the autoscroll distance won't result in scrolling past the content of the scroll view
float minimumLegalDistance = [thumbScrollView contentOffset].x * -1;
float maximumLegalDistance = [thumbScrollView contentSize].width - ([thumbScrollView frame].size.width + [thumbScrollView contentOffset].x);
autoscrollDistance = MAX(autoscrollDistance, minimumLegalDistance);
autoscrollDistance = MIN(autoscrollDistance, maximumLegalDistance);
}
- (void)autoscrollTimerFired:(NSTimer*)timer {
[self legalizeAutoscrollDistance];
// autoscroll by changing content offset
CGPoint contentOffset = [thumbScrollView contentOffset];
contentOffset.x += autoscrollDistance;
[thumbScrollView setContentOffset:contentOffset];
// adjust thumb position so it appears to stay still
ThumbImageView *thumb = (ThumbImageView *)[timer userInfo];
[thumb moveByOffset:CGPointMake(autoscrollDistance, 0)];
}
#pragma mark View handling methods
- (void)toggleThumbView {
[self createSlideUpViewIfNecessary]; // no-op if slideUpView has already been created
CGRect frame = [slideUpView frame];
if (thumbViewShowing) {
frame.origin.y = 0;
} else {
frame.origin.y = -225;
}
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:0.3];
[slideUpView setFrame:frame];
[UIView commitAnimations];
thumbViewShowing = !thumbViewShowing;
}
- (void)pickImageNamed:(NSString *)name {
// first remove previous image view, if any
[[imageScrollView viewWithTag:ZOOM_VIEW_TAG] removeFromSuperview];
UIImage *image = [UIImage imageNamed:[NSString stringWithFormat:#"%#.jpg", name]];
TapDetectingImageView *zoomView = [[TapDetectingImageView alloc] initWithImage:image];
zoomView.autoresizingMask = UIViewAutoresizingFlexibleWidth ;
[zoomView setDelegate:self];
[zoomView setTag:ZOOM_VIEW_TAG];
[imageScrollView addSubview:zoomView];
[imageScrollView setContentSize:[zoomView frame].size];
[zoomView release];
// choose minimum scale so image width fits screen
float minScale = [imageScrollView frame].size.width / [zoomView frame].size.width;
[imageScrollView setMinimumZoomScale:minScale];
[imageScrollView setZoomScale:minScale];
[imageScrollView setContentOffset:CGPointZero];
}
- (NSArray *)imageNames {
// the filenames are stored in a plist in the app bundle, so create array by reading this plist
NSString *path = [[NSBundle mainBundle] pathForResource:#"Images" ofType:#"plist"];
NSData *plistData = [NSData dataWithContentsOfFile:path];
NSString *error; NSPropertyListFormat format;
NSArray *imageNames = [NSPropertyListSerialization propertyListFromData:plistData
mutabilityOption:NSPropertyListImmutable
format:&format
errorDescription:&error];
if (!imageNames) {
NSLog(#"Failed to read image names. Error: %#", error);
[error release];
}
return imageNames;
}
- (void)createSlideUpViewIfNecessary {
if (!slideUpView) {
[self createThumbScrollViewIfNecessary];
CGRect bounds = [[self view] bounds];
float thumbHeight = [thumbScrollView frame].size.height;
float labelHeight = CREDIT_LABEL_HEIGHT;
// create label giving credit for images
UILabel *creditLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, thumbHeight, bounds.size.width, labelHeight)];
[creditLabel setBackgroundColor:[UIColor clearColor]];
[creditLabel setTextColor:[UIColor whiteColor]];
// [creditLabel setFont:[UIFont fontWithName:#"Helvetica" size:16]];
// [creditLabel setText:#"SAMPLE TEXT"];
[creditLabel setTextAlignment:UITextAlignmentCenter];
// create container view that will hold scroll view and label
CGRect frame = CGRectMake(0.0, -225.00, bounds.size.width+256, thumbHeight + labelHeight);
slideUpView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleTopMargin;
slideUpView = [[UIView alloc] initWithFrame:frame];
[slideUpView setBackgroundColor:[UIColor blackColor]];
[slideUpView setOpaque:NO];
[slideUpView setAlpha:.75];
[[self view] addSubview:slideUpView];
// add subviews to container view
[slideUpView addSubview:thumbScrollView];
[slideUpView addSubview:creditLabel];
[creditLabel release];
}
}
- (void)createThumbScrollViewIfNecessary {
if (!thumbScrollView) {
float scrollViewHeight = THUMB_HEIGHT + THUMB_V_PADDING;
float scrollViewWidth = [[self view] bounds].size.width;
thumbScrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, scrollViewWidth, scrollViewHeight)];
[thumbScrollView setCanCancelContentTouches:NO];
[thumbScrollView setClipsToBounds:NO];
// now place all the thumb views as subviews of the scroll view
// and in the course of doing so calculate the content width
float xPosition = THUMB_H_PADDING;
for (NSString *name in [self imageNames]) {
UIImage *thumbImage = [UIImage imageNamed:[NSString stringWithFormat:#"%#_thumb.jpg", name]];
if (thumbImage) {
ThumbImageView *thumbView = [[ThumbImageView alloc] initWithImage:thumbImage];
[thumbView setDelegate:self];
[thumbView setImageName:name];
CGRect frame = [thumbView frame];
frame.origin.y = THUMB_V_PADDING;
frame.origin.x = xPosition;
[thumbView setFrame:frame];
[thumbView setHome:frame];
[thumbScrollView addSubview:thumbView];
[thumbView release];
xPosition += (frame.size.width + THUMB_H_PADDING);
}
}
[thumbScrollView setContentSize:CGSizeMake(xPosition, scrollViewHeight)];
}
}
#pragma mark Utility methods
- (CGRect)zoomRectForScale:(float)scale withCenter:(CGPoint)center {
CGRect zoomRect;
// the zoom rect is in the content view's coordinates.
// At a zoom scale of 1.0, it would be the size of the imageScrollView's bounds.
// As the zoom scale decreases, so more content is visible, the size of the rect grows.
zoomRect.size.height = [imageScrollView frame].size.height / scale;
zoomRect.size.width = [imageScrollView frame].size.width / scale;
// choose an origin so as to get the right center.
zoomRect.origin.x = center.x - (zoomRect.size.width / 2.0);
zoomRect.origin.y = center.y - (zoomRect.size.height / 2.0);
return zoomRect;
}
#pragma mark -
#pragma mark Rotation support
// Ensure that the view controller supports rotation and that the split view can therefore show in both portrait and landscape.
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
return YES;
}
#end
If you've set up your UIScrollView in a Nib file, make sure it is resizing properly when rotated (Use the Autosizing controls in the Size Inspector in Interface Builder: Both sets of arrows inside the box should be red)
Then use this to rescale when the iPad changes orientation:
- (void)willAnimateSecondHalfOfRotationFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation duration:(NSTimeInterval)duration{
//if your UIImageView is called zoomView use this
CGRect zoomRect=CGRectMake(0,0,zoomView.frame.size.width, zoomView.frame.size.height);
[scrollView zoomToRect:zoomRect animated:YES];}
(Sorry about the bad placement of the {} but it wasn't pasting properly as code for some reason)
Hope this helps!