Consider the screen shot above. The UIView is positioned too much to the top causing the upper test string to be partially off and there is a gap shown at the bottom screen. The screen shot also shows its corresponding positioning values in IB : x = 0 and y = 20. So there is actually an offset (y = 20) default to clear the top status bar. But still the status bar shown covers part of the UIView.
The x, y entry is greyed out, so it seems not possible to change its values. Have spent quite some time but still not able to solve this seemingly easy problem. Hope that somebody who is familiar with this could give some hints on how this should be done.
Update :
Have done it in code as suggested. It seems to work ok. If you find any errors please let me know ...
- (void)viewDidLoad
{
CGRect position_and_size;
CGPoint cg_point;
CGSize cg_size;
[super viewDidLoad];
// setup after loading the view from its nib.
NSLog(#" --- Screen loaded --- ");
cg_size.width = 320;
cg_size.height = 460;
cg_point.x = 0;
cg_point.y = 20;
position_and_size.origin = cg_point;
position_and_size.size = cg_size;
[[self view] setFrame : position_and_size];
}
.
The following is the latest screen shot :
The problem is that you're placing a view that's 460 pixels high at {0,0} in a window that's 480 pixels high. The first 20 pixels of your view therefore ends up under the status bar, and the view fails to cover the bottom 20 pixels of the window. You can fix it in any of the following ways:
Change the autoresize options so that the view's size will be automatically adjusted to fill the window.
Resize the view to match the window's bound, either in code or in IB.
Position the view at {0,20}, either in code or in IB.
You can fix it programmatically:
[yourSubView setFrame:self.view.bounds];
Assuming self.view - parent view, where it should fit.
Related
I have a bunch of questions:
How do I position a UIView so that it is on the bottom of the view I am adding it to?
How can I add a subview to a view so that it is positioned in the corner of the superview with a small gap (Like if I want a 'x' cross sign for closing something)
Is their a utility class for easy UIView positioning (and rotation)?
Any references, open source tutorials etc. will be more then welcome!
(a) How do I position a UIView so that it is on the bottom of the view I am adding it to?
OK, let's say you want to position button as a subview at the bottom of view form, you calculate the origin.y of the subview button by subtracting button's height from the height of the form
CGRect buttonFrame = button.frame;
buttonFrame.origin.y = form.bounds.size.height - buttonFrame.size.height;
button.frame = buttonFrame;
[form addSubview:button];
You can change origin horizontal position as well. You want it on the bottom left of form?
buttonFrame.origin.x = 0;
Or on the right edge of form?
buttonFrame.origin.x = form.bounds.size.width - buttonFrame.size.width;
Or in the middle (horizontally) of form?
buttonFrame.origin.x = (form.bounds.size.width - buttonFrame.size.width) / 2;
or another way using CGRectGetMidX (found in CGGeometry utility methods):
buttonFrame.origin.x = CGRectGetMidX(form.bounds) - buttonFrame.size.width/2;
Autoresizing handles adjusting the frame when the parent view's size changes. But you still have to position it first.
int xOffset = 20;
int yOffset = 20;
CGRect BottomRight_NewFrame = CGRectMake((superview.frame.size.width - subview.frame.size.width-xOffset), (superview.frame.size.height - subview.frame.size.height-yOffset), subview.frame.size.width, subview.frame.size.height);
subview.frame = BottomFrame;
You can use the new Autolayout feature of iOS 6 or the old Struts & Springs in the Interface Builder to achieve this.
This tutorial explains both:
http://msmvps.com/blogs/kevinmcneish/archive/2012/12/10/tutorial-ios-6-auto-layout-versus-springs-and-struts.aspx
Or you can set the autoresizing mask programatically. It is explained pretty well here:
UIView autoresizingMask - Interface Builder to Code - Programmatically create struts and springs - Swift or Objective-C
It's easy enough to just set the frame, e.g. (untested code )
subview.frame = CGRectMake((superview.frame.origin.x - subview.frame.origin.size.width/2)-20, (superview.view.frame.origin.y - subview.frame.origin.size.height/2)-20, subview.view.frame.size.width, subview.view.frame.size.height);
if you'll be doing a lot of this then create a utility class or method.
Autolayout will help you position the views and maintain those positions if the size of the superview changes. If the superview isn't going to change, you don't really need to mess with constraints -- you can just set the position of the subview appropra
If you're adding view viewB to view viewA:
a) To position viewB so that it's bottom edge corresponds to the bottom edge of viewA:
viewB.frame.origin.y = viewA.bounds.size.height - viewB.bounds.size.height;
b) You don't say which corner, but it's just a matter of doing the math. For example, the upper right corner of viewA is at {viewA.bounds.size.x, 0} in viewA's coordinate system. If you want to put viewB there, set it's origin to:
{viewA.bounds.size.x-viewB.bounds.size.x, 0}
If you want to add a margin, you can add that to the computation:
int margin = 10;
{viewA.bounds.size.x-viewB.bounds.size.x-margin, margin}
d) Use NSLayoutConstraint to access the autolayout system's constraints programmatically. There's a nice visual format language, so that for your question (a) you could set the constraint for viewA to:
V:|-[viewB]-0-|
The V means that you're working in the vertical direction, |'s represent the edges (top and bottom, thanks to the V) of the superview (that's viewA), and the 0 means that the distance between viewB and the bottom of its superview should be 0.
You can setup constraints in iOS6 but if you want to work on older os's you need to position them manually. Math.
I'm fairly new to programming, and I have looked for an answer for a very long time. There are some posts about it, but nothing has solved my problem. I have a UIScrollView view that I get from the nib, everything is ok with this, the content length is good and scrolling works, but it just scrolls on the left side, if I try to scroll on the right side it doesn't scroll..
Here is the code,
- (void)viewDidLoad {
[super viewDidLoad];
NSString *descriptionString = _currentBook.description;
CGSize stringSize = [descriptionString sizeWithFont:[UIFont boldSystemFontOfSize:16] constrainedToSize:CGSizeMake(387, 9999) lineBreakMode:UILineBreakModeWordWrap];
_authorLabel.text = _currentBook.author;
_titleLabel.text = _currentBook.title;
_descriptionLabel.text = [NSString stringWithFormat:#"Description: %#",_currentBook.description];
[(UIScrollView *)self.view setContentSize:CGSizeMake(387, stringSize.height +50)];
}
Thanks in advance!
Its hard to understand the problem since we cant see your nib file, but its better practice to put the scrollView on top the view of the view controller, and connect it to an IBOutlet in your view controller.
In order to find the problem I would get rid of the textfields for testing purposes (I think the constrained 9999 might be a problem but I am not sure) and then print and post the frame of the scrollView and the Content size in runtime.I am betting that you will see some issue with the frame of the uiscrollview.
Thanks,
Ok, after copy-pasting and running some tests, I found out the problem.
The problem is in the wording of the question, your problem is not that the "scroll doesn't work on the right side" (As in: you move your finger up and down on the right side of the screen without triggering a scroll), the problem is that the contents, the label itself is going out of bounds, outside of the visible area of the scrollView, and the right-handed side is not visible.
First of all, you should note that the iphone resolution is 320x480 (640x960 for Retina), so you actually have to work with a smaller width (using 387 width will make it go out of bounds).
Second, take in account the x position of the label itself is also affecting the amount of visible text. With this in mind, a more generic code would be:
- (void)viewDidLoad
{
[super viewDidLoad];
// This number represents the total width of the label that will fit centered in
// the scrollView area.
CGFloat visibleWidth = self.view.frame.width - descriptionLabel.frame.origin.x*2;
// Use the number above to get a more accurate size for the string.
NSString *descriptionString = _currentBook.description;
CGSize stringSize = [descriptionString sizeWithFont:[UIFont boldSystemFontOfSize:16] constrainedToSize:CGSizeMake(visibleWidth, 9999) lineBreakMode:UILineBreakModeWordWrap];
// Fill data (why so many underscores?)
_authorLabel.text = _currentBook.author;
_titleLabel.text = _currentBook.title;
_descriptionLabel.text = [NSString stringWithFormat:#"Description: %#", _currentBook.description];
// Also, why didn't you resize the description label? I'm assuming that you forgot this.
// (Make sure that the descriptionLabel number of lines is 0)
CGRect frame = descriptionLabel.frame;
descriptionLabel.frame.size = stringSize;
// Now set the content size, since you're using the scrollView as the main view of the viewController,
// I'll asume that it's using the whole screen, so I'm gonna use the whole width
// of the screen (that's what UIScreen is for).
[(UIScrollView *)self.view setContentSize:CGSizeMake([UIScreen mainScreen].bounds.size.width, stringSize.height +50)];
}
Finally i've found my problem, I've added a uiview programmatically as a subview to some view and then to this View i've added my scroll view as a subview.. And then it would only scroll in the area of my UIView. It was nonsense to do it like this, still a lack of knowledge..
Thank you all for trying to help!
Within my view I create a scrollview with a width of 320 and a height of 70.
Responding to the user touching a button, I expand the scrollview, so it is 380(h) x 320(w) in size.
The code for this is shown below:
CGRect scrollviewFrame = CGRectMake(0, 30, 320, 380);
[scrollView setFrame:scrollviewFrame];
[self layoutScrollImages:YES];
CGSize srect = CGSizeMake([scrollView bounds].size.width, (kNumImages * (kScrollObjHeight + 10)));
[scrollView setContentSize:srect];
The constants mentioned in the above snippet are defined as:
const CGFloat kScrollObjHeight = 80;
const NSUInteger kNumImages = 100;
As I debug this project, I can see that srect is 320 (w) x 8000 (h) in size; however my issue is the scrollable area (where the user can actually touch to scroll the scrollview) remains the same as when it was it's original size.
I'm obviously missing something, does anyone know what it is?
have created a sample project to illustrate the issue I am having, it is available here: http://dl.dropbox.com/u/9930498/ScrollViewTest.zip
The problem in your sample is you have a very odd structure for loading your views. As such the view you're adding to the DetailScrollView instance is the root view of the DetailScrollView.xib, not the scrollview itself, which I believe is what you were expecting.
Fastest way to fix your problem is to adjust the root view in DetailScrollView.xib to autoresize width and height.
A UIView cannot respond to touches that are outside of the bounds of its superview. In your example, it appears that you expand the scroll view, but the scroll view's parent is still only 100 units high.
You should imagine the scrollView as a window, where by the window I mean the frame of the scrollView, which is also the coordinates that the scrollView detects your touches. By setting the contentView as 320 (w) x 8000 (h) you only change the content of the scroll view, which is the complete area behind that window.
By expanding content view, the scrollView can scroll a broader area, but in order to detect touches in a bigger rect, you should change frame of the scroll view.
UIView *stateView = [getSomeUIView thisOne];
CGRect currentFrame = stateView.frame;
if(currentFrame.size.height == 0.0) {
currentFrame.size = CGSizeMake(260, 60);
}
else {
currentFrame.size = CGSizeMake(260, 0);
}
stateView.frame = currentFrame;
I would expect all the subviews would be hidden when the height of the frame is set to zero however this does not happen (in the iPhone 4.0.1 Simulator).
Any suggestions why or alternatives?
I was planing to later animate the frame so it's a sliding effect. I can not use the y position and move it off screen nor can I create a element to hide it behind since I'm working with a background image and everything on top is transparent/alpha layer.
I've got the same problem. Solved it with clipsToBounds property:
stateView.clipsToBounds = YES
Subviews will only change size if you set their springs and struts to do so.
By default, they are set to "stay the SAME width and height, and stay the same distance from top left corner of the parent view".
You can set the springs/struts in Interface Builder, or in code. e.g.:
aSubView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
Use UIScrollView instead of UIView. UIScrollView is made to hide "overflow" and works perfectly.
I'm relatively new to objective-c...I'm using the iphone 3.0 SDK
I have a UIView, which is a subview, that I want to resize under certain circumstances.
The way I do it is within a controller class.
for example,
CGSize el = CGSizeMake(30, 40);
[self.subview setSize:el];
the above code does work, but the compiler gives a warning: 'UIView' may not respond to 'setSize:'
At some level, "if it ain't broke, I don't want to fix it", but I'm a little worried that I'm doing something wrong.
Any ideas as to why I'm getting the warning and how I can fix it?
TIA
That probably means that setSize for UIView is implmented but it is not shown in the header file that is imported into the project. That makes it an undocumented API, ie one day it could change and break your code :)
And sure enough if you go to the documentation of UIView you will find no refrence to the size property. So I would avoid it.
What you should use instead is the frame property
CGSize el = CGSizeMake(30, 40);
CGRect bounds = CGself.subview.bounds;
bounds.size = el;
CGself.subview.bounds = bounds;
Give that a shot.
The right thing to do here is use something else instead of the non-public size property. But for the sake of discussion: If you wanted to get rid of the warning, you can declare that you know about the size property somewhere at the top of your implementation file:
#import "MyClass.h"
#interface UIView (private)
- (void) setSize: (CGSize) newSize;
#end
#implementation MyClass
…
#end
The compiler will stop complaining.
Here is a closer explanation using the "frame" property for "myView":
[self.myView.frame = CGRectMake(x, y, width, height)];
Where:
x, coordinate FOR the top left corner of your view having as
reference the top left corner of its parents "x" coordinate.
y, same
as x but y axis
width, horizontal size of the frame
height, vertical size of the frame
i.E. You have a view which fits to the screen bounds, so its coordinate (0,0) will be the same as your device screen top left corner.
if you want to add a subview barely smaller that the screen size and center it horizontally and vertically, here is the set up:
[self.myView.frame = CGRMake ( 20 , 20 , self.view.frame.size.width-40, self.view.frame.size.height-40);
This example sets the frame inside the view and centered. Note that we subtract 40 to the width corresponding to: 20 left side, 20 right side, and so the same for vertical adjustments.
This code will also work in portrait and landscape mode.