I have the following code
- (void) setTargetGoalFrameToLeftOfWindow: (UIView*) goalView orientation: (UIInterfaceOrientation) orientation {
[goalView setTransform:CGAffineTransformMakeRotation(-M_PI_2)];
CGRect goalFrame = goalView.frame;
CGRect windowFrame = [self getWindowFrame];
CGFloat topMargin;
if (UIInterfaceOrientationIsLandscape(orientation)) {
topMargin = (windowFrame.size.width - goalFrame.size.height) / 2.0;
} else {
topMargin = (windowFrame.size.height - goalFrame.size.height) / 2.0;
}
goalView.frame = CGRectMake(GOAL_MARGIN, topMargin, goalFrame.size.width, goalFrame.size.height);
}
I am creating frame with CGRect and I am using it display my UI elements like labels, buttons etc. I am calculating position based on the window size so that they are in appropriate positions in different orientations. When my app is running, I click on home button. When I open the app again, my UI elements are messed up. They are not in proper positions. The method I mentioned above gets invoked every time I change the orientation and open the app. So, this is getting invoked when I reopen the app. But the problem is that, even before the frame is completely formed, it is taking the width and height at that particular point and calculating positions of my UI elements. This is leading to messed up UI. Is there any way where in I can restrict it to take width and height only after the frame is completely formed? Thanks!
Related
I just struggled quite a while with this, so will document it for others.
Here's the problem I was having. With an iPad app, supporting iOS7, I have a modal view controller that has a text field near the bottom the modal. Thus, when the keyboard appears, I wanted to move that modal up so the text field would still be visible with the keyboard present. With iOS8, this problem has a pretty clean solution (e.g., see Moving a modally presented UIViewController up when keyboard appears on iPad with iOS8). With iOS7 I was using self.myNavController.view.superview.center for repositioning, but ran into problems when trying to move the modal given the appearance of the keyboard. The coordinate CGPoint adjustments I was using would not move the modal in the right direction with all four rotations/orientations of the iPad.
The problem in part lies in how iOS7 does the rotation-- with transforms. However, I was unable to resolve the issue using CGPointApplyAffineTransform, or conversion of points using views (e.g., convertPoint:fromView:).
The solution I found to this problem involved a few steps:
1) I found it necessary to change the center of the modal (an assignment to self.myNavController.view.superview.center) relative to the center of the screen. I computed the center of the screen based on [UIScreen mainScreen].bounds.size. For some example code, I used the method screenCenter below.
// Adapted from: http://stackoverflow.com/questions/24150359/is-uiscreen-mainscreen-bounds-size-becoming-orientation-dependent-in-ios8
+ (CGSize) screenSize;
{
CGSize screenSize = [UIScreen mainScreen].bounds.size;
CGSize rotatedSize;
if ([UIDevice ios7OrEarlier] && [[SMRotation session] isLandscape]) {
rotatedSize = CGSizeMake(screenSize.height, screenSize.width);
}
else {
rotatedSize = screenSize;
}
return rotatedSize;
}
+ (CGPoint) screenCenter;
{
CGSize size = [self screenSize];
CGPoint center = CGPointMake(size.width/2.0, size.height/2);
return center;
}
2) Now, given that you have computed the amount that you have to shift the modal upwards (e.g., given the keyboard height and your modal height and the position of the text field on the modal), call this amount dy. I next found it necessary if the app was in an inverted rotation (upside down portrait or landscape), to change the sign of dy before applying it to the CGPoint center position I was calculating. Something like this:
CGPoint newCenter = [SMRotation screenCenter];
if ([SMRotation session].isInverted) {
dy = -dy;
}
newCenter.y += dy;
With some of the code for isInverted here:
- (BOOL) isInverted;
{
switch (self.interfaceOrientation) {
case UIInterfaceOrientationPortraitUpsideDown:
case UIInterfaceOrientationLandscapeRight:
return YES;
case UIInterfaceOrientationPortrait:
case UIInterfaceOrientationLandscapeLeft:
case UIInterfaceOrientationUnknown:
return NO;
}
}
3) Then, if the app was in landscape I found it necessary to swap the x and y coordinates. Something like this:
if ([SMRotation session].isLandscape) {
newCenter = CGPointMake(newCenter.y, newCenter.x);
}
4 Finally, I did the assignment to update the center of the modal:
self.myNavController.view.superview.center = newCenter;
I put UIImageView in my Scene from Object library, and give it an image and defined OUTLET in .h file. Now I want to check its coordinates, or center point, or frame X,Y,Width,Height.
I am using
This
CGRect newFrameSize = CGRectMake(recycleBin.frame.origin.x, recycleBin.frame.origin.y,
recycleBin.frame.size.width, recycleBin.frame.size.height);
or
CGRect newFrameSize = recycleBin.frame;
by using this
NSLog(#"%#", NSStringFromCGRect(newFrameSize));
gives same result that is
2013-01-16 21:42:25.101 xyzapp[6474:c07] {{0, 0}, {0, 0}}
I want its actual position and size when viewcontroller loaded, so when user click on image view it will fadeout by zoom-in towards users and will disappear, and when user tap on reset button, it fadein and zoom-in back to original form (reverse to the previous animation).
Also give me hint, how to perform this animation on UIImageView or any button or label. Thx
Unfortunately, you can't check an item's actual frame as set in IB in -viewDidLoad. The earliest you can check it (that I've found) is by overriding -viewDidAppear:. But, since -viewDidAppear: could be called multiple times throughout the life of the view, you need to make sure you're not saving the frame it's in the modified state.
- (void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
if(savedFrame == CGRectZero) {
savedFrame = self.recycleBin.frame;
NSLog(#"Frame: %#", NSStringFromCGRect(savedFrame));
}
}
Where savedFrame is a member variable (or you could make it a property).
From the description of the animation you're wanting, it sounds like adjusting the frame isn't the way to go about it. It sounds like you're wanting to get the effect of the view stretching and fading out (and the reverse when being reset)? If so, some code like this might be more so what you're looking for...
Fade out:
float animationDuration = 2.0f; // Duration of animation in seconds
float zoomScale = 3.0f; // How much to zoom in duration the animation
[UIView animateWithDuration:animationDuration animations:^{
CGAffineTransform transform = CGAffineTransformMakeScale(zoomScale, zoomScale);
self.recycleBin.transform = transform;
self.recycleBin.alpha = 0; // Make fully transparent
}];
And then, to reset the view:
float animationDuration = 2.0f; // Duration of animation in seconds
[UIView animateWithDuration:animationDuration animations:^{
CGAffineTransform transform = CGAffineTransformMakeScale(1.0f, 1.0f);
self.recycleBin.transform = transform;
self.recycleBin.alpha = 1.0; // Make fully opaque
}];
You can play around with the numbers to see if you get the effects you desire. Most animations in iOS are actually extremely simple to do. This code would work for any UIView subclass.
It sounds as if your IBOutlet is not attached to your class.
Open up your view controller header file (if that is where you property declaration is) and look beside the declaration:
Notice how on the first IBOutlet, the circle (to the left of the line number) is filled in. This means that it is connected to your scene. However, the second one is not (the circle is not filled in).
I have an iPad application that has a base image UIImageView (in this case a large building or site plan or diagram) and then multiple 'pins' can be added on top of the plan (visually similar to Google Maps). These pins are also UIImageViews and are added to the main view on tap gestures. The base image is also added to the main view on viewDidLoad.
I have the base image working with the pinch gesture for zooming but obviously when you zoom the base image all the pins stay in the same x and y coordinates of the main view and loose there relative positioning on the base image (whose x,y and width,height coordinates have changed).
So far i have this...
- (IBAction)planZoom:(UIPinchGestureRecognizer *) recognizer;
{
recognizer.view.transform = CGAffineTransformScale(recognizer.view.transform, recognizer.scale, recognizer.scale);
recognizer.scale = 1;
for (ZonePin *pin in planContainer.subviews) {
if ([pin isKindOfClass:[ZonePin class]]){
CGRect pinFrame = pin.frame;
// ****************************************
// code to reposition the pins goes here...
// ****************************************
pin.frame = pinFrame;
}
}
}
I need help to calculate the math to reposition the pins x/y coordinates to retain there relative position on the zoomed in or out plan/diagram. The pins obviously do not want to be scaled/zoomed at all in terms of their width or height - they just need new x and y coordinates that are relative to there initial positions on the plan.
I have tried to work out the math myself but have struggled to work it through and unfortunately am not yet acquainted with the SDK enough to know if there is provision available built in to help or not.
Help with this math related problem would be really appreciated! :)
Many thanks,
Michael.
InNeedOfMathTuition.com
First, you might try embedding your UIImageView in a UIScrollView so zooming is largely accomplished for you. You can then set the max and min scale easily, and you can scroll around the zoomed image as desired (especially if your pins are subviews of the UIImageView or something else inside the UIScrollView).
As for scaling the locations of the pins, I think it would work to store the original x and y coordinates of each pin (i.e. when the view first loads, when they are first positioned, at scale 1.0). Then when the view is zoomed, set x = (originalX * zoomScale) and y = (originalY * zoomScale).
I had the same problem in an iOS app a couple of years ago, and if I recall correctly, that's how I accomplished it.
EDIT: Below is more detail about how I accomplished this (I'm looking my old code now).
I had a UIScrollView as a subview of my main view, and my UIImageView as a subview of that. My buttons were added to the scroll view, and I kept their original locations (at zoom 1.0) stored for reference.
In -(void)scrollViewDidScroll:(UIScrollView *)scrollView method:
for (id element in myButtons)
{
UIButton *theButton = (UIButton *)element;
CGPoint originalPoint = //get original location however you want
[theButton setFrame:CGRectMake(
(originalPoint.x - theButton.frame.size.width / 2) * scrollView.zoomScale,
(originalPoint.y - theButton.frame.size.height / 2) * scrollView.zoomScale,
theButton.frame.size.width, theButton.frame.size.height)];
}
For the -(UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView method, I returned my UIImageView. My buttons scaled in size, but I didn't include that in the code above. If you're finding that the pins are scaling in size automatically, you might have to store their original sizes as well as original coordinates and use that in the setFrame call.
UPDATE...
Thanks to 'Mr. Jefferson' help in his answer above, albeit with a differing implementation, I was able to work this one through as follows...
I have a scrollView which has a plan/diagram image as a subview. The scrollView is setup for zooming/panning etc, this includes adding UIScrollViewDelegate to the ViewController.
On user double tapping on the plan/diagram a pin image is added as a subview to the scrollView at the touch point. The pin image is a custom 'ZonePin' class which inherits from UIImageView and has a couple of additional properties including 'baseX' and 'baseY'.
The code for adding the pins...
- (IBAction)planDoubleTap:(UITapGestureRecognizer *) recognizer;
{
UIImage *image = [UIImage imageNamed:#"Pin.png"];
ZonePin *newPin = [[ZonePin alloc] initWithImage:image];
CGPoint touchPoint = [recognizer locationInView:planContainer];
CGFloat placementX = touchPoint.x - (image.size.width / 2);
CGFloat placementY = touchPoint.y - image.size.height;
newPin.frame = CGRectMake(placementX, placementY, image.size.width, image.size.height);
newPin.zoneRef = [NSString stringWithFormat:#"%#%d", #"BF", pinSeq++];
newPin.baseX = placementX;
newPin.baseY = placementY;
[planContainer addSubview:newPin];
}
I then have two functions for handling the scrollView interaction and this handles the scaling/repositioning of the pins relative to the plan image. These methods are as follows...
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView
{
return planImage;
}
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
for (ZonePin *pin in planContainer.subviews) {
if ([pin isKindOfClass:[ZonePin class]]){
CGFloat newX, newY;
newX = (pin.baseX * scrollView.zoomScale) + (((pin.frame.size.width * scrollView.zoomScale) - pin.frame.size.width) / 2);
newY = (pin.baseY * scrollView.zoomScale) + ((pin.frame.size.height * scrollView.zoomScale) - pin.frame.size.height);
CGRect pinFrame = pin.frame;
pinFrame.origin.x = newX;
pinFrame.origin.y = newY;
pin.frame = pinFrame;
}
}
}
For reference, the calculations for position the pins, by the nature of them being pins' centres the pin image on the x axis but has the y-axis bottom aligned.
The only thing left for me to do with this is to reverse the calculations used in the scrollViewDidScroll method when I add pins when zoomed in. The code for adding pins above will only work properly when the scrollView.zoomScale is 1.0.
Other than that, it now works great! :)
I have two instances of NSScrollView both presenting a view on the same content. The second scroll view however has a scaled down version of the document view presented in the first scroll view. Both width and height can be individually scaled and the original width - height constraints can be lost, but this is of no importance.
I have the synchronised scrolling working, even taking into account that the second scroll view needs to align its scrolling behaviour based on the scaling. There's one little snag I've been pulling my hairs out over:
As both views happily scroll along the smaller view needs to slowly catch up with the larger view, so that they both "arrive" at the end of their document at the same time. Right now this is not happening and the result is that the smaller view is at "end-of-document" before the larger view.
The code for synchronised scrolling is based on the example found in Apple's documentation titled "Synchronizing Scroll Views". I have adapted the synchronizedViewContentBoundsDidChange: to the following code:
- (void) synchronizedViewContentBoundsDidChange: (NSNotification *) notification {
// get the changed content view from the notification
NSClipView *changedContentView = [notification object];
// get the origin of the NSClipView of the scroll view that
// we're watching
NSPoint changedBoundsOrigin = [changedContentView documentVisibleRect].origin;;
// get our current origin
NSPoint curOffset = [[self contentView] bounds].origin;
NSPoint newOffset = curOffset;
// scrolling is synchronized in the horizontal plane
// so only modify the x component of the offset
// "scale" variable will correct for difference in size between views
NSSize ownSize = [[self documentView] frame].size;
NSSize otherSize = [[[self synchronizedScrollView] documentView] frame].size;
float scale = otherSize.width / ownSize.width;
newOffset.x = floor(changedBoundsOrigin.x / scale);
// if our synced position is different from our current
// position, reposition our content view
if (!NSEqualPoints(curOffset, changedBoundsOrigin)) {
// note that a scroll view watching this one will
// get notified here
[[self contentView] scrollToPoint:newOffset];
// we have to tell the NSScrollView to update its
// scrollers
[self reflectScrolledClipView:[self contentView]];
}
}
How would I need to change that code so that the required effect (both scroll bars arriving at an end of document) is achieved?
EDIT: Some clarification as it was confusing when I read it back myself: The smaller view needs to slow down when scrolling the first view reaches the end. This would probably mean re-evaluating that scaling factor... but how?
EDIT 2: I changed the method based on Alex's suggestion:
NSScroller *myScroll = [self horizontalScroller];
NSScroller *otherScroll = [[self synchronizedScrollView] horizontalScroller];
//[otherScroll setFloatValue: [myScroll floatValue]];
NSLog(#"My scroller value: %f", [myScroll floatValue]);
NSLog(#"Other scroller value: %f", [otherScroll floatValue]);
// Get the changed content view from the notification.
NSClipView *changedContentView = [notification object];
// Get the origin of the NSClipView of the scroll view that we're watching.
NSPoint changedBoundsOrigin = [changedContentView documentVisibleRect].origin;;
// Get our current origin.
NSPoint curOffset = [[self contentView] bounds].origin;
NSPoint newOffset = curOffset;
// Scrolling is synchronized in the horizontal plane so only modify the x component of the offset.
NSSize ownSize = [[self documentView] frame].size;
newOffset.x = floor(ownSize.width * [otherScroll floatValue]);
// If our synced position is different from our current position, reposition our content view.
if (!NSEqualPoints(curOffset, changedBoundsOrigin)) {
// Note that a scroll view watching this one will get notified here.
[[self contentView] scrollToPoint: newOffset];
// We have to tell the NSScrollView to update its scrollers.
[self reflectScrolledClipView:[self contentView]];
}
Using this method the smaller view is "overtaken" by the larger view when both scrollers reach a value of 0.7, which is not good. The larger view then scrolls past its end of document.
I think you might be approaching this in the wrong way. I think you should be getting a percentage of how far down each scroll be is scrolled in relation to itself and apply that to the other view. One example of how this could be done is this way using NSScroller's -floatValue:
NSScroller *myScroll = [self verticalScroller];
NSScroller *otherScroll = [otherScrollView verticalScroller];
[myScroll setFloatValue:otherScroll.floatValue];
I finally figured it out. The answer from Alex was a good hint but not the full solution as just setting the float value of a scroller doesn't do anything. That value needs translation to specific coordinates to which the scroll view needs to scroll its contents.
However, due to differences in size of the scrolled document view, you cannot just simply use this value, as the scaled down view will be overtaken by the "normal" view at some point. This will cause the normal view to scroll past its end of document.
The second part of the solution was to make the normal sized view wait with scrolling until the scaled down view has scrolled its own width.
The code:
// Scrolling is synchronized in the horizontal plane so only modify the x component of the offset.
NSSize ownSize = [[self documentView] frame].size;
newOffset.x = MAX(floor(ownSize.width * [otherScroll floatValue] - [self frame].size.width),0);
The waiting is achieved by subtracting the width of the scroll view from the width times the value of the scroller. When the scaled down version is still traversing its first scroll view width of pixels, this calculation will result in a negative offset. Using MAX will prevent strange effects and the original view will quietly wait until the value turns positive and then start its own scrolling. This solution also works when the user resizes the app window.
I'm trying to resize a UITextView when the keyboard shows. On iPhone it works beautifully. When the the system dispatches a keyboard notification, the text view resizes. When it's done editing, I resize it to fill in the initial space. (Yes, I'm assuming the keyboard is gone when the editing stops. I should change that. However, I don't think that's my issue.)
When I resize the textview on the iPad, the frame resizes correctly, but the app seems to reset the Y value of the frame to zero. Here's my code:
- (void) keyboardDidShowWithNotification:(NSNotification *)aNotification{
//
// If the content view being edited
// then show shrink it to fit above the keyboard.
//
if ([self.contentTextView isFirstResponder]) {
//
// Grab the keyboard size "meta data"
//
NSDictionary *info = [aNotification userInfo];
CGSize kbSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;
//
// Calculate the amount of the view that the keyboard hides.
//
// Here we do some confusing math voodoo.
//
// Get the bottom of the screen, subtract that
// from the keyboard height, then take the
// difference and set that as the bottom inset
// of the content text view.
//
float screenHeightMinusBottom = self.contentTextView.frame.size.height + self.contentTextView.frame.origin.y;
float heightOfBottom = self.view.frame.size.height - screenHeightMinusBottom;
float insetAmount = kbSize.height - heightOfBottom;
//
// Don't stretch the text to reach the keyboard if it's shorter.
//
if (insetAmount < 0) {
return;
}
self.keyboardOverlapPortrait = insetAmount;
float initialOriginX = self.contentTextView.frame.origin.x;
float initialOriginY = self.contentTextView.frame.origin.y;
[self.contentTextView setFrame:CGRectMake(initialOriginX, initialOriginY, self.contentTextView.frame.size.width, self.contentTextView.frame.size.height-insetAmount)];
}
Why would this work on iPhone, and not work on iPad? Also, can my autoresize masks be making an unexpected change?
Like said #bandejapaisa, I found that the orientation was a problem, at least during my tests.
The first thing, is about the use of kbSize.height being misleading, because in Landscape orientation it represents the width of the keyboard. So, as your code is in a UIViewController you can use it this way:
float insetAmount = (UIInterfaceOrientationIsPortrait(self.interfaceOrientation)?kbSize.height:kbSize.width) - heightOfBottom;
The self.interfaceOrientation gives the orientation of the Interface (can be different from the Device orientation) and the macro UIInterfaceOrientationIsPortrait returns YES if the given orientation is Portrait (top or bottom). So as the keyboard height is in the kbSize.height when the interface is Portrait, and in the kbSize.width when the interface is Landscape, we simply need to test the orientation to get the good value.
But that's not enough, cause I've discovered the same problem with the self.view.frame.size.height value. So I used the same workaround:
float heightOfBottom = (UIInterfaceOrientationIsPortrait(self.interfaceOrientation)?self.view.frame.size.height:self.view.frame.size.width) - screenHeightMinusBottom;
Hope this helps...