iPhone navigation bar rotation issue when coming back from background - objective-c

Ok, so after weeks of headache, I've given up and decided to turn to expert resource online!
Basically, I am trying to get my iphone application to view in a forced landscape mode (to be precise, for a graph) for just 1 view controller in otherwise a portrait-orientation dominated navigation-bar application.
I got everything working the way it should, EXCEPT when I put the application into background and return, the application returns with the navigation bar moved to where it usually sits in Portrait orientation mode but rotated 90', whilst every others like status bar, the main view are all still in landscape mode.
I've tried to manually correct the navigation bar orientation afterwards, but cocoa seems to ignore this bit of code. It's almost as if the self.view.transform doesn't work when the application returns from background mode. Any suggestions?
LandscapeViewController.m
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return NO;
}
-(void)viewWillAppear:(BOOL)animated {
self.view.transform = CGAffineTransformMakeRotation((M_PI * (90) / 180.0));
self.view.bounds = CGRectMake(0.0, 0.0, 480, 320);
}
This image shows you can see what I mean
http://i.stack.imgur.com/Qx1Si.png

Have you tried this?
-(BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return UIInterfaceOrientationIsLandscape(interfaceOrientation);
}

You should not always return NO from shouldAutorotateToInterfaceOrientation: but return YES for the orientation you support. The iOS then handles the rest.

Related

iOS9 covering status bar with custom uiwindow - wrong position

I am trying to cover status bar with my own view and to do that I calculcate frame for my view by doing something like that (also after rotation):
UIScreen *screen = [UIScreen mainScreen];
CGRect statusBarFrame = [UIApplication sharedApplication].statusBarFrame;
For iOS8+ (because since ios8 UIScreen is orientantion-dependant):
CGRect frame = [screen.coordinateSpace convertRect:statusBarFrame toCoordinateSpace:screen.fixedCoordinateSpace];
[self setFrame:frame];
For iOS7:
[self setFrame:statusBarFrame];
It works just fine for iOS8 and below but when building my app with Xcode 7 beta 4 and iOS 9 SDK something is wrong when starting app in landscape or upsidedown (it works fine if app starts in portrait) ...
ie. when I start the app while Upsidedown the custom uiwindow which should cover status bar will always end up at the bottom side of screen, any ideas what might be wrong?
Without additional information, the best solution would be to simply hide the status bar. If you still want the "status bar" for animation purposes or some other reason, the typical solution in this scenario is to simulate it by calling
- (UIView *)snapshotViewAfterScreenUpdates:(BOOL)afterUpdates on UIScreen
and use the returned view as the background for whatever view/window you're presenting. As of iOS 9, there's no public method that'll allow you to get the specific behavior you specified.

CATiledLayer being removed and refreshed while zoomed in iPad 3rd gen

I'm experiencing a redraw problem on a CATiledLayer when the parent UIScrollView is zoomed in.
I'm rendering a PDF page in a CATiledLayer backed UIView. It has another UIImageView behind it, which contains a low-res image of the page that the CATiledLayer will draw. When I zoom in, it works as expected. The CATiledLayer will render a higher resolution image according to the zoom level.
The problem occurs after zooming. If I zoom in then just leave the iPad alone, the displayed image blurs then resharpens. It looks like the CATiledLayer is being removed, since I see the blurry low resolution image in the backing view, then the CATiledLayer gets redrawn, i.e. I see the tiling effect and the resharpening of the image. This happens if I just leave the app alone and wait about 30 to 40 seconds. I've only observed it on the iPad 3rd gen (New iPad, iPad3, whatever). I'm also testing on iPad2s and I have yet to encounter the issue.
Has anyone else encountered this problem? Any known cause and, possibly, solutions?
Edit:
My UIScrollViewDelegate methods are as follows:
// currentPage, previousPage, and nextPage are the pdf page views
// that are having the refresh problem
- (void)positionBufferedPages {
// performs math {code omitted}
// then sets the center of the views
[previousPage.view setCenter:...];
[nextPage.view setCenter:...];
}
- (void)hideBufferedPages {
if ([previousPage.view isDescendantOfView:scrollView]) {
[previousPage.view removeFromSuperview];
}
if ([nextPage.view isDescendantOfView:scrollView]) {
[nextPage.view removeFromSuperview];
}
}
- (void)showBufferedPages {
if (![previousPage.view isDescendantOfView:scrollView]) {
[scrollView addSubview:previousPage.view];
}
if (![nextPage.view isDescendantOfView:scrollView]) {
[scrollView addSubview:nextPage.view];
}
if (![currentPage.view isDescendantOfView:scrollView]) {
[scrollView addSubview:currentPage.view];
}
}
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView {
return currentPage.view;
}
- (void)scrollViewWillBeginZooming:(UIScrollView *)scrollView withView:(UIView *)view {
[self hideBufferedPages];
}
- (void)scrollViewDidEndZooming:(UIScrollView *)scrollViewParam withView:(UIView *)view atScale:(float)scale {
[self positionBufferedPages];
[self showBufferedPages];
}
- (void)scrollViewDidZoom:(UIScrollView *)scrollView {
// nothing relating to the pdf page view
// but does set the center of some other subviews on top of the pdf page views
}
Not sure how helpful this will be though, as the scrollview is not receiving input while the problem happens. As mentioned above, the pdf page is loaded to the CATiledLayer, then I leave the iPad alone (no input is received by the device), and the CATiledLayer will redraw by itself.
I've also tried catching calls to setNeedsDisplay, setNeedsDisplayInRect:, setNeedsLayout, and setNeedsDisplayOnBoundsChange: on both the view and the tiled layer, but the redraw happens without any of those functions getting called. drawLayer:inContext: gets called, of course, but the trace only shows some Quartz calls being started in a background thread (as expected, as tiled layers prepare the content in the background), so it is of no help either.
Thanks in advance!
How is your app's memory usage looking? CATiledLayer will discard its cache and redraw if a memory warning occurs. I've seen it do this even without memory warnings being sent to the app (just a higher than usual memory load). Use Instruments to see memory usage. You may need to use the OpenGL ES Driver instrument to see what's going on with graphics memory.
I spoke with an Apple engineer about this and the short answer is that iOS only has X amount of memory available for caching a CATiledLayer and on the Retina display of the iPad, there are just too many pixels to use more than one layer.
I had been using two CATileLayers to display a map view and a drawing view on top. I removed the second CATiledLayer and the problem went away.
I've had the exact same problem. In my case it was caused by using the UIGraphicsBeginImageContext() function; this function does not take scale into account, which gives problems on a retina display. The solution was to replace the call with UIGraphicsBeginImageContextWithOptions(), with the scale (=third) parameter set to 0.0.
If you based your code on the Zooming PDF Viewer sample code from Apple, like I did, chances are this will solve your problem too.
Longshot, any chance you are calling any methods on the views from the non-main thread? All sorts of unexpected funky stuff can happen if you do.

Stop UIToolbar from Disappearing in Landscape Orientation - iPad

Not sure why this happens or how to stop it, my UIToolBar on the details viewcontroller is only visible during portrait view. I want it visible at all orientations. How do I do that? Thank you.
I encountered the same problem by just dragging a UIToolBar on to my view and docking it on the top of the window. It showed up in landscape but not portrait. Interface Builder - at least the one embedded in Xcode 4 - doesn't seem to do the right thing with the resize masks.
While Kshitiz's answer above will work, it has a couple of flaws. As coded, it does not support all four orientations. More importantly, it's not resolution independent.
A better solution is briefly described in enamrik's comment, so credit should go to him/her. Here are the steps:
Select the tool bar in Interface Builder.
Open the Size inspector.
In the Autosizing box, select the left, right and top "i-beams" on the exterior of the square. This keeps the position of the toolbar fixed relative to the sides of the view when the view is resized.
Inside the Autosizing square, select the horizontal line with arrows on both ends. This causes the size of the toolbar to change in sync with the parent view.
in your this function of view controller reset view frame bro
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
// Override to allow orientations other than the default portrait orientation.
if (interfaceOrientation==UIInterfaceOrientationLandscapeLeft || interfaceOrientation==UIInterfaceOrientationLandscapeRight) {
self.view.frame = CGRectMake(0, 0, 703,768);
} else {
self.view.frame = CGRectMake(0, 0, 768, 1024);
}
return YES;
}
and your tool bar frame too
good luck
Faced the same problem when I add UIPickerView programmatically and add UIToolBar for the PickerView. Just need to add [.flexibleWidth,.flexibleHeight] for the UIPickerView. eg:-
let statTypePicker = UIPickerView()
And then add
self.statTypePicker.autoresizingMask = [.flexibleWidth,.flexibleHeight]

Why aren't my views being positioned correctly on interfaceOrientation changes?

I have a UIViewController one UIWebView in it. I'd like the UIWebView to be positioned in the centre of the iPad screen in landscape and portrait modes. So, I've implemented it like this
// UIViewController
// InfoGraphicView is the UIWebView
-(BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
// Overriden to allow any orientation.
return YES;
}
- (void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation
duration:(NSTimeInterval)duration {
if (toInterfaceOrientation == UIInterfaceOrientationPortrait ||
toInterfaceOrientation == UIInterfaceOrientationPortraitUpsideDown) {
[self layoutPortrait];
} else {
[self layoutLandscape];
}
}
- (void)layoutLandscape {
NSLog(#"Layout Landscape");
infoGraphicView.frame = CGRectMake(100, 100, 936, 700);
}
- (void)layoutPortrait {
NSLog(#"Layout Portrait");
infoGraphicView.frame = CGRectMake(100, 100, 700, 936);
}
However, it's not behaving as I expected. In the above code, I would expectt he UIWebView to be 100px (or points or whatever the unit is) away from the top and the left. But it's not. In Portrait mode it appears flush with the top left of the screen, and in Landscape mode it seems to be partially offscreen in the top left.
If I set the frame as CGRectMake(-100, 100, 700, 936) then I get it positioned in the center of the screen as I'd like it to be, but I've no idea why.
As usual, there's most likely something simple I'm overlooking but I can't figure it out. Any help greatly appreciated as always.
The coordinates you set on infoGraphicView are relative to its superview, not to the screen generally. And views don't necessarily clip their subviews. Furthermore, the shape set automatically to self.view will depend on the scaling flags set in Interface Builder. However, I think that by default it is set to fill the whole screen.
That said, I think the mistake is in your use of willRotateToInterfaceOrientation:duration:. That is called before the rotation begins, so self.view has the old size (ie, it'll still be portrait sized if rotating from portrait to landscape and vice versa). Probably better to hook willAnimateRotationToInterfaceOrientation:duration: — then the correct size has been set and you'll be within the CoreAnimation block so your view will grow/shrink as part of the rotation animation.
It's also worth checking which resizing flags you have set on infoGraphicView. They'll take effect automatically, in addition to any changes you make. So you probably want to disable them all.
This probably is an issue with the view that the web view is in. The coordinate system used is that of the view’s superview. If that view isn’t being resized on rotation, then you’ll see unexpected layout like this. You can access the superview of a view through the superview property; one way to see its frame would be to use its description. Put this line in one of your layout methods:
NSLog(#"Superview: %#", [infoGraphicView superview]);
That should print out a description of the view.
Once you get that figured out, if you want the web view to have the same layout, you can use its autoresizingMask property. If you set it like this:
infoGraphicView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
Then the view will automatically change its width and height to keep the top, left, right, and bottom margins the same.

Landscape only View in Cocoa Touch

Is there to way to fix a view's orientation in a landscape position, regardless of the device's current position?
To be more specific, I have a UIWebView in a UINavigationController that should always show its content as if the device were rotated 90 degress counterclockwise. I only want the web view to be restricted to this orientation; every other view in the app should behave normally.
Yes. In your info.plist file, define:
UIInterfaceOrientation UIInterfaceOrientationLandscapeRight
EDIT:
The above changes the orientation for the whole app, and you say you don't want that. Can the user move the phone to achieve the orientation you need?
If you don't want to rely on the user to change the phone to that orientation, try:
self.view.transform = CGAffineTransformMakeRotation((M_PI * (90) / 180.0));
self.view.bounds = CGRectMake(0.0, 0.0, 480, 320);
In the controller for the view, implement shouldAutorotateToInterfaceOrientation:
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)orientation {
return UIInterfaceOrientationIsLandscape(orientation);
}
Or if you only want to allow Left Landscape (the default for the Youtube app, for example)
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)orientation {
return orientation == UIInterfaceOrientationLandscapeRight;
}