I am newbie so my question can be really obvious, but I didn't find any solution so far.
I did in IB UIScrollView and connected it with File's Owner.
I would like to set now the frame size of my UIScrollView (named ScrollView).
const CGFloat BoardWidth = 320;
const CGFloat BoardHeight = 400;
//I tried this way but 'Expression is assignable' - said Xcode
ScrollView.frame.size.width = BoardWidth;
ScrollView.frame.size.height = BoardWidth;
So how can I the easiest set own sizes of ScrollView frame?
CGRect scrollFrame = CGRrectMake(x, y, w, h);
ScrollView.frame = scrollFrame;
Or if you need only to change the width and height;
CGRect scrollFrame;
scrollFrame.origin = ScrollView.frame.origin;
scrollFrame.size = CGSizeMake(w, h);
ScrollView.frame = scrollFrame;
Edit keeping the center unchanged:
CGRect scrollFrame;
CGFloat newX = scrollView.frame.origin.x + (scrollView.frame.size.width - w) / 2;
CGFloat newY = scrollView.frame.origin.y + (scrollView.frame.size.height - y) / 2;
scrollFrame.origin = CGPointMake(newX, newY);
scrollFrame.size = CGSizeMake(w, h);
scrollView.frame = scrollFrame;
you need to do this, for example.
ScrollView.frame = CGRectMake(0, 0, BoardWidth, BoardHeight);
Once done you need also to set contentSize property. It's the area that 'extends' behind the frame of your UIScrollView.
If you want to scroll only horizontally:
ScrollView.contentSize = CGSizeMake(w * BoardWidth, BoardHeight);
If you want to scroll only vertically:
ScrollView.contentSize = CGSizeMake(BoardWidth, h * BoardHeight);
If you want to scroll both horizontally and vertically:
ScrollView.contentSize = CGSizeMake(w * BoardWidth, h * BoardHeight);
where w and h are generic values to increment your width and/or your height.
If you want have an horizontal (for example) discrete scroll (e.g. you have some pages with the same dimension of your screen).
ScrollView.pagingEnabled = YES;
ScrollView.contentSize = CGSizeMake(p * BoardWidth, BoardHeight);
where p is the number of pages you want to display.
Hope it helps.
You can do it as below,
scrollView.frame = CGRectMake(xOrigin,yOrigin,width,height);
If you are looking for content size of scrollview then it as below,
scrollView.contentSize = CGSizeMake(width,height);
CGRect Frame = ScrollView.frame
Frame.frame.size.width = BoardWidth;
Frame.frame.size.width = BoardWidth;
ScrollView.frame = Frame;
Since frame is a structure..you can't set the frame of an object directly.. You will have to make a Cgrect and then manipulate it.
using contentSize property
ScrollView.contentSize = CGSizeMake(320, 520);
it needs to be bigger than the frame so it actually scrolls.
Related
I want to set the width of the uilabel based on the text length and then on top of that make it a little bit wider. The text might be different so I cannot just predefine the width of the uilabel. My approach to this is to get the width of the text and then add another 10.0 to it but it doesn't work.
CGSize tSize = [[self.label1 text] sizeWithAttributes:#{NSFontAttributeName:[self.label1 font]}];
CGFloat tWidth = tSize.width + 10.0;
self.label1.frame = CGRectMake(self.label1.frame.origin.x, self.label1.frame.origin.y, tWidth, self.label1.frame.size.height);
self.label1.backgroundColor = [UIColor blueColor];
Any advice is much appreciated.
You might want to use [yourLabel sizeToFit]; or [yourLabel sizeThatFits: <#your target size#>];
sizeToFit resizes your label within it's current frame.size according to it's current text , font and the numberOfLines you provided.
Then you can change the size
[yourLabel sizeToFit];
CGRect rect = yourLabel.frame;
rect.size.width += 10;
yourLabel.frame = rect;
sizeThatFits:(CGSize)size doesn't resize your label but it returns the size that fits the size you pass as parameter.
sizeToFit uses sizeThatFits:(CGSize)size internally.
You can change size by doing this
CGSize exampleSize = (CGSize){300, 300};
CGSize fittingSize = [yourLabel sizeThatFits: exampleSize];
CGRect rect = yourLabel.frame;
rect.size.width = fittingSize.width;
rect.size.height = fittingSize.height;
yourLabel.frame = rect;
This should be working fine even if you are working with yourLabel.attributedText
I have a view with image view and Label. Image view displays images of varying sizes and it is fixed to the top(see image) I want to dynamically glue text label to the bottom of every image without any space between image thumbnail and UILabel.
You can do that programically. I assume that you have UILabel attached to "label" and the image to "imageView" variables.
CGRect labelFrame = label.frame;
labelFrame.origin.y = imageView.frame.origin.y + imageView.frame.size.height + any_space_you_want_between_image_and_label;
label.frame = labelFrame;
That will change the position of label just bellow the imageView. I hope this helps.
Because as you mentioned you use UIViewContentModeScaleAspectFit for the content mode the solution is a bit harder.
You have to actually calculate the final height of the image (the actual size of the image inside the UIImageView):
//UIImage *img = ...; UIImageView *imgView = ....
CGFloat imageWidth = img.size.width;
CGFloat imageHeight = img.size.height;
CGFloat viewWidth = imgView.frame.size.width;
CGFloat viewHeight = imgView.frame.size.height;
float actualHeight = imageHeight * viewWidth / imageWidth;
// this is the actual height of the UIImage inside the UIImageView
CGRect labelFrame = label.frame;
labelFrame.origin.y = imageView.frame.origin.y + actualHeight + any_space_you_want_between_image_and_label;
label.frame = labelFrame;
I want to draw a XoY coordinate axis... The axis are CGRects .. the thing is they change width when the device is rotated ... I would want them to maintain their with in all rotations. Does width 5.0 mean different things when the device is in portrait rather than landscape?
Here is the code:
CGContextSaveGState(ctx);
CGContextSetFillColorWithColor(ctx, [[UIColor whiteColor] CGColor]);
// the axis is a rect ...
//axis start point
CGFloat axisStartX = viewBounds.size.width * LEFT_EXCLUSION_LENGTH_PERCENT;
CGFloat axisStartY = viewBounds.size.height * UNDER_EXCLUSION_LENGTH_PERCENT;
CGFloat axisLength = viewBounds .size.height - (viewBounds.size.height * OVER_EXCLUSION_LENGTH_PERCENT) - viewBounds.size.height * UNDER_EXCLUSION_LENGTH_PERCENT;
CGContextAddRect(ctx, CGRectMake(axisStartX, axisStartY, AXIS_LINE_WIDTH, axisLength));
CGContextFillPath(ctx);
CGContextRestoreGState(ctx);
I would not know what you are up to with this calculation, but viewBounds.size.height may change on rotation, depending on what it represents. But if its height varies for different orientations then the axisLength will vary too. And axisLength is the height of your rect.
If you want you rect to be of same size in every orientation than do this!
CGContextSaveGState(ctx);
CGContextSetFillColorWithColor(ctx, [[UIColor whiteColor] CGColor]);
// the axis is a rect ...
//axis start point
CGFloat boxSize = MIN(viewBounds.size.width, viewBounds.size.height);
CGFloat axisStartX = boxSize * LEFT_EXCLUSION_LENGTH_PERCENT;
CGFloat axisStartY = boxSize * UNDER_EXCLUSION_LENGTH_PERCENT;
CGFloat axisLength = boxSize - (boxSize * OVER_EXCLUSION_LENGTH_PERCENT) - boxSize * UNDER_EXCLUSION_LENGTH_PERCENT;
CGContextAddRect(ctx, CGRectMake(axisStartX, axisStartY, AXIS_LINE_WIDTH, axisLength));
CGContextFillPath(ctx);
CGContextRestoreGState(ctx);
The idea here is that whatever the orientation is, the size remains same and visible on screen.
hope that helps!
I want to scroll my UIScrollView (horizontally). But when the button is pressed it goes the left most side of the scroll view. I want to scroll it 3,4 pixels and when I press again it scrolls another 3,4 pixels
- (IBAction)leftScroll:(id)sender
{
CGPoint pt;
pt.x = 1;
pt.y = 0;
UIScrollView *sv = (UIScrollView *)[self.view viewWithTag:5];
[sv setContentOffset:pt animated:YES];
}
Thanks in advance for your answer
Try it and set a new position manually.
Objective-c
float width = CGRectGetWidth(scrollView.frame);
float height = CGRectGetHeight(scrollView.frame);
float newPosition = scrollView.contentOffset.x+width;
CGRect toVisible = CGRectMake(newPosition, 0, width, height);
[scrollView scrollRectToVisible:toVisible animated:YES];
Swift 4
let scrollView = UIScrollView()
let width: CGFloat = scrollView.frame.size.width
let height: CGFloat = scrollView.frame.size.height
let newPosition: CGFloat = scrollView.contentOffset.x + width
let toVisible: CGRect = CGRect(x: newPosition, y: 0, width: width, height: height)
scrollView.scrollRectToVisible(toVisible, animated: true)
You can use [scrollView setContentOffset:CGPointMake(x, y) animated:YES]; method. If your scrollView scrolls horizontally then you need to set x value accordingly, else y value.
You can scroll to some point in a scroll view with the following in Obj-C
[scrollView setContentOffset:CGPointMake(x, y) animated:YES];
or Swift
scrollView.contentOffset = CGPoint(x: x, y: y)
To do slideshows with UIScrollView, you arrange all images in the scroll view, set up a repeated timer, then -setContentOffset:animated: when the timer fires.
UIButton *locatorbutton_frame=(UIButton *)[scrollviewoutlet viewWithTag:numberglobal];
float width = scrollviewoutlet.frame.size.width;
float height = scrollviewoutlet.frame.size.height;
float newPosition = scrollviewoutlet.contentOffset.x-locatorbutton_frame.frame.size.width;//+width;
CGRect toVisible = CGRectMake(newPosition, 0, width, height);
[scrollviewoutlet scrollRectToVisible:toVisible animated:YES];
I found it working fine locatorbutton_frame is the button that i added to the scrollview.
What about:
Objective-C
CGRect visible = [targetView.superview() convertRect:targetView.frame toView:scrollView];
[scrollView scrollRectToVisible:visible animated:YES];
Swift
let visible: CGRect = targetView.superview().convertRect(targetView.frame, toView: scrollView)
scrollView.scrollRectToVisible(visible, animated: true)
I tested the Objective-C code, and it works in every screen orientation.
Here my dilemma. I have 4 elements inside a UIScrollView.
1. Top most element is a UILabel that I give height dynamically depending upon the amount of content in it.
2. Second is a fixed height UILabel that I give position dynamically depending upon the height given to the upper UILabel
3. Third element is a UIImageView that again I have to give position dynamically depending upon the height given to the topmost UILabel
4. The fourth is a UIWebView, to which I gave both, height & position dynamically. (Height depending upon the content in it.. and position again depending on the height of topmost UILabel)
Finally, I dynamically give height to my UIScrollView to accomodate all of the above elements.
Here is the code I use in - (void)webViewDidFinishLoad:(UIWebView *)webView to accomplish all of the above.
//Adjust height of top-most UILabel
CGSize maximumLabelSize = CGSizeMake(300,9999);
CGSize expectedLabelSize = [item.label1 sizeWithFont:label1.font constrainedToSize:maximumLabelSize lineBreakMode:label1.lineBreakMode];
CGRect newFrame = label1.frame;
newFrame.size.height = 0;
newFrame.size.height = expectedLabelSize.height;
label1.frame = newFrame;
//Adjust position of second UILlabel
CGRect labelPosition = label2.frame;
labelPosition.size.height = 20;
labelPosition.origin.y = expectedLabelSize.height +14;
label2.frame = labelPosition;
//Add UIImageView and adjust it's position
UIImageView *image;
image = [[UIImageView alloc] initWithFrame:CGRectMake(0, expectedLabelSize.height +41, 320, 2)];
image.image = [UIImage imageNamed:#"image.png"];
[scrollView addSubview:image];
[image release];
//Adjust UIWebView height and position
CGRect frame = webView.frame;
frame.size.height = 0;
frame.origin.y = expectedLabelSize.height +48;
webView.frame = frame;
CGSize fittingSize = [webView sizeThatFits:CGSizeZero];
frame.size = fittingSize;
webView.frame = frame;
//Adjust Scrollview height
scrollView.contentSize = CGSizeMake(320, fittingSize.height +expectedLabelSize.height +48);
Finally, my problem is that when I first load this view, everything but the scrollview get's proper height & position. But, if I go back one view & open this view again, the scrollview has the desired height.
Any ideas what I might be doing wrong here?
My guess is that the scrollView variable isn't yet initialized when this first runs. Try setting a breakpoint somewhere in this code and checking if scrollView has a value or if it's just 0x00000000.