Fitting an Image to Screen on Rotation iPhone / iPad ?
- by user356937
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....
olsonvox.com/photos/correct.png
However, this is what My screen is looking like.
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
