UIWebView problem with size adjustment when rotating device - iphone

I have a UIWebview in which a have a local html placed . When the ipad shifts, i rearange the elements so that the UIWebView is smaller/bigger after the case. The problem is that although when i sift and adjust the width, although the width is adjusted, the text isn't . The text is visible only in the webview's frame but it goes offscreen (some text is hidden, it continues to some point not being visible) . How can i adjust the webview content width ?

I have faced this problem and what i did to solve is like this ... create a mothod
-(void)reconfigureFrame
{
[_yourWebView loadHTMLString:[NSString stringWithFormat:#"<html><body style='background-color: transparent; width: 280px; margin: 0; padding: 0;color:black;'><div id='ContentDiv'>%#</div></body></html>",theStringToShow] baseURL:nil];
}
in webView:DidLoad delegate method do this
NSString *contentHeight = [webView stringByEvaluatingJavaScriptFromString:#"document.getElementById('ContentDiv').offsetHeight"];
CGRect frame = [containtView frame];
//containtView holds webView
frame.size.height = [contentHeight floatValue] + 10;
[containtView setFrame:frame];
frame = [webView frame];
frame.origin.x = 10;
frame.origin.y = 5;
frame.size.width = containtView.frame.size.width - 2*frame.origin.x;
frame.size.height = [contentHeight floatValue];
[webView setFrame:frame];
and in didAutoRotate just call the first method

Related

Dynamic height of UIWebView with auto layout

I have a problem with setting the height of an UIWebView dynamically. The webview loads a product description which contains html. I want the UIWebView to change its height based on the contents of the description. The parent scrollview should also change its height, but then based on the height of the UIWebView.
Can anyone explain to me how I can achieve the desired behavior of my views?
This is my view hierarchy:
You have to add some code in the delegate method of UIWebView named webViewDidFinishLoad. Here is what you can do:
- (void)webViewDidFinishLoad:(UIWebView *)webView
{
CGRect frame = webView.frame;
frame.size.height = 1;
webView.frame = frame;
CGSize fittingSize = [webView sizeThatFits:CGSizeZero];
frame.size = fittingSize;
webView.frame = frame;
NSLog(#"size: %f, %f", fittingSize.width, fittingSize.height);
yourScrollView.contentSize = webView.bounds.size;
}
The same thing can also be achieved using javascript to find the right height which is as follow:
- (void)webViewDidFinishLoad:(UIWebView *)webView
{
CGRect oldBounds = [[self webView] bounds];
CGFloat height = [[webView stringByEvaluatingJavaScriptFromString:#"document.height"] floatValue];
NSLog(#"NEW HEIGHT %f", height);
[webView setBounds:CGRectMake(oldBounds.origin.x, oldBounds.origin.y, oldBounds.size.width, height)];
yourScrollView.contentSize = webView.bounds.size;
}
Hope it helps!
I actually had the same problem recently and ended up figuring it out and putting together a sample project on github.
You can set a constant height constraint on your WebView and change that dynamically once you calculate the height from the response.
Also constraint between a child view and a parent view can be achieved by this method in NSLayoutConstraint
+ (id)constraintWithItem:(id)view1 attribute:(NSLayoutAttribute)attr1 relatedBy:(NSLayoutRelation)relation toItem:(id)view2 attribute:(NSLayoutAttribute)attr2 multiplier:(CGFloat)multiplier constant:(CGFloat)c

UITextView will not resize

I have tried resizing a UITextView (inside a tableViewCell) to the content size. but it will not change its height at all. I have even changed the height of the UITableViewCell. What could be wrong?
- (void) setTextViewContents: (NSString*) string
{
[textView setText:string];
CGRect frame2 = self.frame;
frame2.size.height = 10000;
self.frame = frame2;
/* resize the view */
CGRect frame = textView.frame;
frame.size.height = textView.contentSize.height+60;
textView.frame = frame;
The string does appear on the view but the size does not change.
Try calling the -[UIView sizeToFit] method.

UIWebView won't resize to fit content?

My webView is not resizing properly after it finished loading. I have tried this code.
- (void)webViewDidFinishLoad:(UIWebView *)webview {
CGRect frame = webView.frame;
frame.size.height = 1;
frame.size.width = screenWidth;
webView.frame = frame;
CGSize fittingSize = [webView sizeThatFits:CGSizeZero];
frame.size = fittingSize;
webView.frame = frame;
[bodyScroll setContentSize:CGSizeMake(screenWidth, webView.frame.origin.y + webView.frame.size.height+keyboardRectY+60)];
It is incresing the width beyond the screenWidth and hence my content horizontally expands beyond the view size which I don't want.
changing
CGSize fittingSize = [webView sizeThatFits:CGSizeMake(screenWidht, 1)];
also leads to the same situation.
How can I get rid of this? The webview width should always remain as screenwidth and only it's height should adjust based on the content size so that the webView just about fits the whole content.
Thanks in Advance
When setting the size of frame, you are overwriting the width you set previously. This should it:
...
CGSize fittingSize = [webView sizeThatFits:CGSizeZero];
fittingSize.width = screenWidth; // Add this
frame.size = fittingSize
...

UIScrollView Rotation Issues

I have a scrollview that automatically generates a series of subviews containing imageviews. The concept is that it's pretty much a custom PDF style reader, where each page is loaded in to an imageview as an image. There are three "layers" - the outer UIScrollView, the automatically generated subViews and the imageview inside the subview.
I've been having some trouble with this, I've asked the question previously, but unfortunately, the core of my question was in the wrong place. Here is my second attempt:
On rotate, everything is rotated as needed. Unfortunately, this is what I'm getting:
Obviously, I would like Image 1 to be centred and for there to be no hint of image 2 until you flick the view across.
Here is my code for setting up the view:
- (void)loadView {
[self setUpView];
}
- (void)setUpView {
//INITIALISE PAGING SCROLL VIEW
CGRect pagingScrollViewFrame = [[UIScreen mainScreen] bounds];
pagingScrollViewFrame.origin.x -= 10;
pagingScrollViewFrame.size.width += 20;
pagingScrollView = [[UIScrollView alloc] initWithFrame:pagingScrollViewFrame];
pagingScrollView.contentMode = UIViewContentModeScaleAspectFit;
//CONFIGURE PAGING SCROLL VIEW
pagingScrollView.pagingEnabled = YES;
pagingScrollView.backgroundColor = [UIColor blackColor];
pagingScrollView.contentSize = CGSizeMake(pagingScrollViewFrame.size.width*7, pagingScrollViewFrame.size.height);
//ACTIVATE PAGING SCROLL VIEW
self.view = pagingScrollView;
//ADD PAGES TO SCROLL VIEW
for (int i = 0; i < 7; i++){
ImageScrollView *page = [[[ImageScrollView alloc] init] autorelease];
[self configurePage:page forIndex:i];
[pagingScrollView addSubview:page];
}
}
How do I re-define the size of the frame? What function should I call etc. How do I centre the image?
I'm new to this so I apologise for the ambiguity of my question.
Cheers
I've figured it out. It was the Frame of the individual pages that I needed to change, so (with the help gained from another question) I wrote a re-orient method.
The first step to this came because I figured out that I needed to iterate through and re-size each frame for each of my pages and then re-apply the frames to the view. For this to happen I needed to create an array which I would fill in the For Loop above. I have 7 total pages.
Then I could (on rotate) call the below re-orient method to re-size each view:
- (void) reOrient{
if(UIInterfaceOrientationIsPortrait(self.interfaceOrientation)){
CGRect f;
int i = 0;
for (ImageScrollView *page in pageArray) {
f = page.frame;
f.size.width = 320;
f.origin.x = (f.size.width * i);
page.frame = f;
pagingScrollView.contentSize = CGSizeMake(f.size.width * 7, 480);
i++;
}
}else{
CGRect f;
int i = 0;
for (ImageScrollView *page in pageArray) {
f = page.frame;
f.size.width = 480;
f.origin.x = (f.size.width * i);
page.frame = f;
pagingScrollView.contentSize = CGSizeMake(f.size.width * 7, 480);
i++;
}
}
}
This worked for me:
- (void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration
{
[super willRotateToInterfaceOrientation:toInterfaceOrientation duration:duration];
//get current page based on offset before rotation
NSInteger currentPage = self.scrollView.contentOffset.x / self.scrollView.bounds.size.width;
//set anticipated scrollview content size by switching width and height (they will be switched after rotation)
[self.scrollView setContentSize:CGSizeMake(totalPages * self.view.bounds.size.height, self.view.bounds.size.width)];
//set the anticipated content offset based on height before rotation
[self.scrollView setContentOffset:CGPointMake(currentPage * self.scrollView.bounds.size.height, 0.0f)];
}
Basically I am setting the content offset for the new scrollview content size before rotating (I'm switching height and width for the anticipated height and width).
This worked for me when rotating a full-screen paged UIScrollView.
All of the paged subviews have the following autoresizing mask so that they neatly fall into place after rotation:
UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleRightMargin

Is it Possible to Center Content in a UIScrollView Like Apple's Photos App?

I have been struggling with this problem for some time and there seems to be no clear answer. Please let me know if anyone has figured this out.
I want to display a photo in a UIScrollView that is centered on the screen (the image may be in portrait or landscape orientation).
I want to be able to zoom and pan the image only to the edge of the image as in the photos app.
I've tried altering the contentInset in the viewDidEndZooming method and that sort of does the trick, but there's several glitches.
I've also tried making the imageView the same size as the scrollView and centering the image there. The problem is that when you zoom, you can scroll around the entire imageView and part of the image may scroll off the view.
I found a similar post here and gave my best workaround, but no real answer was found:
UIScrollView with centered UIImageView, like Photos app
One elegant way to center the content of UISCrollView is this.
Add one observer to the contentSize of your UIScrollView, so this method will be called everytime the content change...
[myScrollView addObserver:delegate
forKeyPath:#"contentSize"
options:(NSKeyValueObservingOptionNew)
context:NULL];
Now on your observer method:
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {
// Correct Object Class.
UIScrollView *pointer = object;
// Calculate Center.
CGFloat topCorrect = ([pointer bounds].size.height - [pointer viewWithTag:100].bounds.size.height * [pointer zoomScale]) / 2.0 ;
topCorrect = ( topCorrect < 0.0 ? 0.0 : topCorrect );
topCorrect = topCorrect - ( pointer.frame.origin.y - imageGallery.frame.origin.y );
// Apply Correct Center.
pointer.center = CGPointMake(pointer.center.x,
pointer.center.y + topCorrect ); }
You should change the [pointer
viewWithTag:100]. Replace by your
content view UIView.
Also change imageGallery pointing to your window size.
This will correct the center of the content everytime his size change.
NOTE: The only way this content don't works very well is with standard zoom functionality of the UIScrollView.
This code should work on most versions of iOS (and has been tested to work on 3.1 upwards).
It's based on the Apple WWDC code for the PhotoScroll app.
Add the below to your subclass of UIScrollView, and replace tileContainerView with the view containing your image or tiles:
- (void)layoutSubviews {
[super layoutSubviews];
// center the image as it becomes smaller than the size of the screen
CGSize boundsSize = self.bounds.size;
CGRect frameToCenter = tileContainerView.frame;
// center horizontally
if (frameToCenter.size.width < boundsSize.width)
frameToCenter.origin.x = (boundsSize.width - frameToCenter.size.width) / 2;
else
frameToCenter.origin.x = 0;
// center vertically
if (frameToCenter.size.height < boundsSize.height)
frameToCenter.origin.y = (boundsSize.height - frameToCenter.size.height) / 2;
else
frameToCenter.origin.y = 0;
tileContainerView.frame = frameToCenter;
}
Here is the best solution I could come up with for this problem. The trick is to constantly readjust the imageView's frame. I find this works much better than constantly adjusting the contentInsets or contentOffSets. I had to add a bit of extra code to accommodate both portrait and landscape images.
If anyone can come up with a better way to do it, I would love to hear it.
Here's the code:
- (void) scrollViewDidEndZooming:(UIScrollView *)scrollView withView:(UIView *)view atScale:(float)scale {
CGSize screenSize = [[self view] bounds].size;
if (myScrollView.zoomScale <= initialZoom +0.01) //This resolves a problem with the code not working correctly when zooming all the way out.
{
imageView.frame = [[self view] bounds];
[myScrollView setZoomScale:myScrollView.zoomScale +0.01];
}
if (myScrollView.zoomScale > initialZoom)
{
if (CGImageGetWidth(temporaryImage.CGImage) > CGImageGetHeight(temporaryImage.CGImage)) //If the image is wider than tall, do the following...
{
if (screenSize.height >= CGImageGetHeight(temporaryImage.CGImage) * [myScrollView zoomScale]) //If the height of the screen is greater than the zoomed height of the image do the following...
{
imageView.frame = CGRectMake(0, 0, 320*(myScrollView.zoomScale), 368);
}
if (screenSize.height < CGImageGetHeight(temporaryImage.CGImage) * [myScrollView zoomScale]) //If the height of the screen is less than the zoomed height of the image do the following...
{
imageView.frame = CGRectMake(0, 0, 320*(myScrollView.zoomScale), CGImageGetHeight(temporaryImage.CGImage) * [myScrollView zoomScale]);
}
}
if (CGImageGetWidth(temporaryImage.CGImage) < CGImageGetHeight(temporaryImage.CGImage)) //If the image is taller than wide, do the following...
{
CGFloat portraitHeight;
if (CGImageGetHeight(temporaryImage.CGImage) * [myScrollView zoomScale] < 368)
{ portraitHeight = 368;}
else {portraitHeight = CGImageGetHeight(temporaryImage.CGImage) * [myScrollView zoomScale];}
if (screenSize.width >= CGImageGetWidth(temporaryImage.CGImage) * [myScrollView zoomScale]) //If the width of the screen is greater than the zoomed width of the image do the following...
{
imageView.frame = CGRectMake(0, 0, 320, portraitHeight);
}
if (screenSize.width < CGImageGetWidth (temporaryImage.CGImage) * [myScrollView zoomScale]) //If the width of the screen is less than the zoomed width of the image do the following...
{
imageView.frame = CGRectMake(0, 0, CGImageGetWidth(temporaryImage.CGImage) * [myScrollView zoomScale], portraitHeight);
}
}
[myScrollView setZoomScale:myScrollView.zoomScale -0.01];
}
Here is how I calculate the the min zoom scale in the viewDidLoad method.
CGSize photoSize = [temporaryImage size];
CGSize screenSize = [[self view] bounds].size;
CGFloat widthRatio = screenSize.width / photoSize.width;
CGFloat heightRatio = screenSize.height / photoSize.height;
initialZoom = (widthRatio > heightRatio) ? heightRatio : widthRatio;
[myScrollView setMinimumZoomScale:initialZoom];
[myScrollView setZoomScale:initialZoom];
[myScrollView setMaximumZoomScale:3.0];