UIButtons in a UIView - iphone

I have a UIScrollview with an IBOutlet mapped to ganttScroller. This UIScrollView has a UIView in it. I made the UIView in IB and its width is 100.
I then start to add buttons to that UIView (mapped via an IBOutlet scrollContent)
float test = [scrollContent frame].size.width;
for (int i=0; i<15; i++) {
UIButton *showButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
showButton.frame = CGRectMake(55.0 * i,
50.0,
50.0,
20.0);
[showButton setTitle:NSLocalizedString(#"test", #"") forStates:UIControlStateNormal];
[scrollContent addSubview:showButton];
}
test = [scrollContent frame].size.width;
[scrollContent sizeToFit];
test =[scrollContent frame].size.width;
At the beginning I check the size of my scrollContent and it is indeed 100 (checked 'test' in the debugger), after adding the buttons it is again 100, and after sizeToFit it is still 100 (I would expect a lot larger since all those buttons were added... The buttons are shown correctly!
I need the correct size for my gantScroller (UIScrollView)
What is wrong ?

I don't think -[UIView sizeToFit] actually takes in to account its subviews. You'll need to simply calculate the correct width and assign that to the view's frame. You'll then also need to set the scroll view's contentSize property so that it scrolls correctly.
Probably the reason you see all the buttons despite the container being too small is that UIViews do not clip their subviews by default.

Related

Autosizing a UIView that contains a UITextView

I have a UITableViewController with a UIView before the table view. The UIView (IBOutlet UIView *templateDescriptionView) has a UITextView (IBOutlet UITextView *templateDescription) in it. It looks like this:
The UITextView can have a variable amount of text. I'm trying to programmatically resize the UITextView and UIView to compensate for this, but it's not working as expected.
-(void) viewDidLoad
{
[templateDescription sizeToFit];
CGRect frame = templateDescription.frame;
frame.size.height = templateDescription.contentSize.height;
templateDescription.frame = frame;
CGRect viewFrame = templateDescriptionView.frame;
viewFrame.size.height = templateDescription.contentSize.height + 40; // 40 for padding
templateDescriptionView.frame = viewFrame;
}
The problem is, when everything renders, the UIView is partially on top of the UITableView. It resizes, but it's not resizing to the proper height. What am I doing wrong? This is Xcode 5, iOS7.
I am afraid I misunderstood your meaning. But UITableViewController is used to control a UITableView. Does it run well that a UITableViewController control a UIView? Maybe you put a UIView into the HeaderInSection of tableView. In iOS7, self.automaticallyAdjustsScrollViewInsets = NO; can be used to remove the space inset in scrollview.

Calculate the contentsize of scrollview

I'm having a scrollview as the detailedview of tableview cell. There are multiple views on the detailedview like labels, buttons etc. which I'm creating through interface builder. What I'm creating through interface builder is static. I'm putting everything on a view of height 480.
A label on my detailedview is having dynamic text which can extend to any length. The problem is that I need to set the scrollview's content size for which I need its height.
How shall I set scrollview's height provided the content is dynamic?
You could try to use the scrollview'ers ContentSize. It worked for me and I had the same problem with the control using dynamic content.
// Calculate scroll view size
float sizeOfContent = 0;
int i;
for (i = 0; i < [myScrollView.subviews count]; i++) {
UIView *view =[myScrollView.subviews objectAtIndex:i];
sizeOfContent += view.frame.size.height;
}
// Set content size for scroll view
myScrollView.contentSize = CGSizeMake(myScrollView.frame.size.width, sizeOfContent);
I do this in the method called viewWillAppear in the controller for the view that holds the scrollview. It is the last thing i do before calling the viewDidLoad on the super.
Hope it will solve your problem.
//hannes
Correct shorter example:
float hgt=0; for (UIView *view in scrollView1.subviews) hgt+=view.frame.size.height;
[scrollView1 setContentSize:CGSizeMake(scrollView1.frame.size.width,hgt)];
Note that this only sums heights, e.g. if there are two subviews side by side their heights with both be added, making the sum greater than it should be. Also, if there are vertical gaps between the subviews, the sum will be less than it should be. Wrong height confuses scrollRectToVisible, giving random scroll positions :)
This loop is working and tested:
float thisy,maxy=0;for (UIView *view in scrollView1.subviews) {
thisy=view.frame.origin.y+view.frame.size.height; maxy=(thisy>maxy) ? thisy : maxy;
}
A somewhat easier way to do this is to nest your layout within a view then put that view within the scrollview. Assuming you use tags, this works as follows:
UIScrollView *scrollview = (UIScrollView *)[self.view viewWithTag:1];
UIView *longView = (UIView *)[self.view viewWithTag:2];
scrollview.contentSize = CGSizeMake(scrollView.frame.size.width, longView.frame.size.height);
That way the longView knows how tall it is, and the scrollview's content is just set to match.
This depends on the type of content you are going to add dynamically. So let's say you have a big text data to show, then use the UITextView and as it is a subclass of the UIScrollView, you can get the setContentSize of TextView when you assign the text content. Based on that you can set the total size of the UIScrollView.
float yPoint = 0.0f;
UIScrollView *myScrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0.0f, yPoint, 320.0f, 400.0f)];
UITextView *calculatorTextView = [[UITextView alloc] init]; calculatorTextView.text = #"My looong content text ..... this has a dynamic content"; `
[calculatorTextView sizeToFit];
yPoint = yPoint + calculatorTextView.contentSize.height; // Bingo, we have the new yPoint now to start the next component.
// Now you know the height of your text and where it will end. So you can create a Label or another TextView and display your text there. You can add those components as subview to the scrollview.
UITextView *myDisplayContent = [[UITextView alloc] initWithFrame:CGRectMake(0.0f, yPoint, 300.f, calculatorTextView.contentSize.height)];
myDisplayContent.text = #"My lengthy text ....";
[myScrollView addSubview:myDisplayContent];
// At the end, set the content size of the 'myScrollView' to the total length of the display area.
[myScrollView setContentSize:yPoint + heightOfLastComponent];
This works for me.
I guess there's no auto in case of scrollview, and the contentsize should be calculated for static views on the screen at least and for dynamic once it should be calculated on the go.
scrollView.contentSize = [scrollView sizeThatFits:scrollView.frame.size]
I believe would also work
I had the same situation, but then I wrote a new version in Swift 4 mirroring the better answer in Objective-C by Hannes Larsson:
import UIKit
extension UIScrollView {
func fitSizeOfContent() {
let sumHeight = self.subviews.map({$0.frame.size.height}).reduce(0, {x, y in x + y})
self.contentSize = CGSize(width: self.frame.width, height: sumHeight)
}
}

UIButton only responds in a small area

I'm trying to add a UIButton to a UIView, but am having some trouble with getting it to respond to touches.
I have a method which returns UIButtons after I provide it with a tag:
- (UIButton*)niceSizeButtonWithTag:(int)tag {
UIButton * aButton = [UIButton buttonWithType:UIButtonTypeCustom];
[aButton setTag:tag];
[aButton addTarget:self action:#selector(buttonWasTapped:) forControlEvents:UIControlEventTouchUpInside];
CGRect newFrame = aButton.frame;
newFrame.size.width = 44;
newFrame.size.height = 44;
[aButton setFrame:newFrame];
return aButton;
}
As you can see I'm creating a new button and increasing the size.
I use this in the following way:
UIButton * anotherButton = [self niceSizeButtonWithTag:1];
[anotherButton setImage:[UIImage imageNamed:#"image" withExtension:#"png"] forState:UIControlStateNormal];
[anotherButton setCenter:CGPointMake(middleOfView)];
[aView addSubview:anotherButton];
I create a lot of buttons like this, hence the reason for the method.
The buttons are always created and added to the subview perfectly. I can see the image and they're in the correct position. The problem is that they only respond to touches in a tiny strip.
In this attached image,
alt text http://web1.twitpic.com/img/107755085-5bffdcb66beb6674d01bb951094b0e55.4c017948-full.png
The yellow shows the whole frame of the button,
The red shows the area that will respond to touches.
The grey shows a section of the view the button is added to.
If anyone could shed some light on why this is happening, it would be really useful.
UPDATE:
I should probably mention I'm trying to add this button to a UIView which is a subview of a UITableViewCell.
UPDATE 2:
Adding it directly to the UITableViewCell works, adding it to the UIView on the UITableViewCell is causing the error.
FINAL UPDATE
The problem turned out to be that I was sending the view containing the button to the back of the subviews on the UITableViewCell. Getting rid of the sendSubviewToBack: call fixed it.
Do you have any other views added to this containing view after you add the button? try setting some of your view's background color to blueColor, redColor and other colors to better see what the stack of views in your app is like. Then you should be easily able to see if there is some sort of view blocking the button.

how to put multiple buttons in scroll view?

how i can put multiple buttons in scroll view with according to my requirement?
Well, something like this would work:
UIButton *button1 = ... // (allocate this and initialize it)
UIButton *button2 = ... // (allocate this and initialize it)
UIScrollView *scrollView = ... // (allocate this and initialize it)
[scrollView addSubview:button1];
[scrollView addSubview:button2];
This is basically how you add 2 buttons to a UIScrollView.
Now, if you want to do more, like put them so that only one is visible at a time or something, then position the frame of each button inside the scrollView.contentSize bounds.

UIButtons over a UIImageView Zooming

I am pretty new to iphone programming. I just started about a month ago and have only been tinkering with small tutorial type applications but anyways, here is my question.
I currently have a UIScrollView thats scrollable and zoomable, that loads a UIImageView subview, and i want to add in some controls(UIButtons) over the image view but when i zoom in and out the whole group(the buttons and the image) zoom togeather.
If I add the UIButtons to my UIScrollView and zoom, the image zooms and the buttons stay in origional place
If I add the UIButtons to my UIImageView they zoom correctly but arent buttons anymore. IE they lose their interactivity.
Later ill add lots of buttons into an array and add them.
I would appreciate any help i can get
This is part of my mainViewController.m:
- (void)viewDidLoad
{
[scrollView2 setBackgroundColor:[UIColor blackColor]];
[scrollView2 setCanCancelContentTouches:NO];
scrollView2.clipsToBounds = YES; // default is NO, we want to restrict drawing within our scrollview
scrollView2.indicatorStyle = UIScrollViewIndicatorStyleWhite;
scroll2ImageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"bigNH.jpg"]];
[scrollView2 addSubview:scroll2ImageView];
[scrollView2 setContentSize:CGSizeMake(scroll2ImageView.frame.size.width, scroll2ImageView.frame.size.height)];
scrollView2.minimumZoomScale = .5;
scrollView2.maximumZoomScale = 3;
scrollView2.delegate = self;
[scrollView2 setScrollEnabled:YES];
UIButton *myButton = [UIButton buttonWithType:UIButtonTypeCustom];
CGRect newSize = CGRectMake(658, 435, 50, 50); // position in the parent view and set the size of the button
myButton.frame = newSize;
[myButton setImage:[UIImage imageNamed:#"redStop.png"] forState:UIControlStateNormal];
// add targets and actions
[myButton addTarget:self action:#selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside];
// add to a view
[scroll2ImageView addSubview:myButton];
[redLineArray addObject:myButton];
[scroll2ImageView release];
}
This might not help and it is not what it appears that you want to do.
However, when I want buttons associated with a scrollview, I add a parent view, add the buttons to that view and also add the scrollview to that view. The button(s) and the scrollview would be siblings. This allows the user to scroll around the contents of the scrollview, while insuring that the buttons are always in view.
-isdi-
By default, UIImageView has userInteraction disabled. Have you changed this?
Also, I would be really uneasy adding subviews to an UIImageView, it's really meant to hold one image. It would be better to create a normal UIView and add the UIButtons and UIImageView to that. It's very easy to control the ordering so that the buttons appears on top of the image.
P.S. Just to make your life easier, instead of :
[scrollView2 setContentSize:CGSizeMake(scroll2ImageView.frame.size.width, scroll2ImageView.frame.size.height)];
You can use :
[scrollView2 setContentSize:scroll2ImageView.frame.size];
Make a single view to contain all your zoomable content (everything it would appear), and call it say contentView. Now place everything you want in that contentView, the imageView and all your buttons etc.
In your UIScrollView delegate place this: (Be sure to set the scrollView's delegate if you haven't already)
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView {
return self.contentView;
}
Only one view is allowed to zoom, but that one view can however contain other views that will scale because they're child views.
Also be sure to set the scrollView's contentSize value to the exact size of your zoomable contentView.