How to make vertical CCScrollView align to top? - objective-c

I have a vertical CCScrollView on iOS where height is not divisible by cell height.
So, cells align to the bottom of CCScrollView.
Is there any way to make CCScrollView align to top?

I have not used the CCScrollView, but I have tried another UIScrollView implementation for cocos2d and I think the same way I solved this could apply. Set your scrollview's contentOffset to ccp(0.0, scrollview.contentSize.height - scrollview.size.height) instead of ccp(0.0, 0.0). Then, adjust the position of your content based on your scrollview's contentSize. For instance if you wanted your content's position to be ccp(x, y) as it appears, you could do something like
content.position = CGPointMake(x, scrollview.contentSize.height - scrollview.size.height + y)
size is the view size of the scrollview, but I'm not sure what the actual property for scrollview is since I haven't used it.

Use below code works for me:
[self.scrollView setContentOffset:ccp(0, -self.scrollView.container.contentSize.height + self.scrollView.boundingBox.size.height) animated:NO];

Related

How to customize a NSSlider

I'm trying to implement a custom slider in Cocoa with 5 values. See my demo project, which can be downloaded here: http://s000.tinyupload.com/index.php?file_id=07311576247413689572.
I've subclassed the NSSliderCell and implemented methods like drawKnob:(NSRect)knobRect and drawBarInside:(NSRect)cellFrame flipped:(BOOL)flipped etc.
I'm facing some issues:
I'm not able to position the knob correctly regarding to the background image. I know that I'm able to change the knob's frame, and I've tried doing some calculation to position the knob correctly, but I'm not able to make it work for my custom slider. Could someone please help me with this?
The height of my custom slider background is 41px. In the drawBarInside:(NSRect)cellFrame flipped:(BOOL)flipped I change the height of the frame to 41px as well, but the entire background is not visible. Why?
I've noticed that the included images (the background and knob) are flipped vertically. Why? Note that the border top is darker in the background compared to the bottom, but this is reversed when I draw the background.
I found a mistake in your calculation of the x position of the knob rectangle: You used the height of the image where you should have used the width.
The cell drawing is being clipped to the frame of the control. Maybe you could expand the control frame when your cell awakes.
You need to use the NSImage method drawInRect:fromRect:operation:fraction:respectFlipped:hints:, and pass YES for the respectFlipped: parameter. Apple's controls generally do use flipped coordinates.
Added: Expanding the frame in awakeFromNib doesn't seem to work, the frame gets set back. Here's something that does work. Instead of overriding drawBarInside:flipped:, add this override:
- (void)drawWithFrame:(NSRect)cellFrame inView:(NSView *)controlView
{
NSRect controlFrame = [controlView frame];
float bgHeight = self.backgroundImage.size.height;
if (controlFrame.size.height < bgHeight)
{
controlFrame.size.height = bgHeight;
[controlView setFrame: controlFrame];
}
[self.backgroundImage
drawInRect: [controlView bounds]
fromRect: NSZeroRect
operation: NSCompositeSourceOver
fraction: 1.0
respectFlipped: YES
hints: NULL];
[self drawKnob];
}

How to get the padding from the edge of the UITableview to the UITableViewCell

On the iPad, the Grouped style tableview's cells are inset deeper from the edge of the tableview than on the iPhone.
I need to retrieve the Left and Right distances from the edges of the tableview to where the cell begins. What i'm referring to is similar to "Margins". I read the UITableview API up and down and can't find a property that returns this.
I need to use this in calculation to compute where to position content in my cells.
Thanks in advance!
Alex
I haven't tested this but i'm pretty sure you should just be able to pick up the frame of both and then compare from there.
CGRect cellFrame = yourCell.frame;
CGRect tableFrame = yourUITableView.frame;
The CGRect values are (x coordinate, y coordinate, width, height).
Also you can just print out the frames using :
NSLog(#"your cell frame is %#",NSStringFromCGRect(yourCell.frame);
NSLog(#"your table frame is %#",NSStringFromCGRect(yourUITableView.frame);
I solved this with overriding the layoutSubviews call for the iPad and setting the grouped view margins to what I want them to be, rather then what the apparently hidden value is. Other answers in Stack point out that it can vary from 10 to 45 pixels in width.
In your CustomTableViewCell class
- (void)layoutSubviews
{
CGRect f = self.bounds;
f = CGRectInset(f, 10, 0);
self.contentView.frame = f;
self.backgroundView.frame = f;
}
You could force it to keep contentView and backgroundView to be equal to that of the TableCell width which is that TableView width, but in this case I still wanted my grouped view to be inset a little bit. It also allows you to better match with a custom header/footer view which will go edge to edge without work.

How to synchronize UIScrollView image with another UIImageView

I'm designing a game that has a large hex style map in a UIScrollView and a 1/10th scale "mini map" in another view. The mini map has a rectile that is used to indicate the current area visible in the scroll view. What's the best way to position the rectile to synchronize it with the main map?
You can get your UIScrollView's contentOffset whenever you'd like. You could check this value in the UIScrollView delegate method - (void)scrollViewDidScroll:(UIScrollView *)scrollView. Once you have the contentOffset you should divide that by your UIScrollView's contentSize minus it's frame.size. That gives you a float, that float can then be used to determine the positioning of the rectile in the smaller view. Some code below to show what I'm talking about. I'm just going to give you the x positioning example. rinse and repeat for y positioning.
- (void)scrollViewDidScroll:(UIScrollView *)scrollView {
CGFloat xRat;
CGFloat xPos;
xRat = scrollView.contentOffset.x/(scrollView.contentSize.width - scrollView.frame.size.width);
}
The xRat is the percentage (in float format) that the scroll view has scrolled. So just use xRat to position the rectile along the x-axis by that percentage.

iOS: Orientation get future self.view.bounds

Background: I wanted to animate the change in my content along with the orientation. My content position is relative to the self.view.bounds.
Problem: In order to animate the content along with the bounds, I would need to know what would the bounds of the view be at the end. I can hard code it but I hope to find a more dynamic way.
Codes: So all animation takes place in willRotateToInterfaceOrientation as per following:
- (void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration {
//centering the image
imageView.frame = CGRectMake(self.view.bounds.origin.x + (self.view.bounds.size.width - image.size.width)/2 , self.view.bounds.origin.y + (self.view.bounds.size.height - image.size.height)/2, image.size.width, image.size.height);
NSLog(#"%d",[[UIDevice currentDevice] orientation]);
NSLog(#"%f", self.view.bounds.origin.x);
NSLog(#"%f", self.view.bounds.origin.y);
NSLog(#"%f", self.view.bounds.size.width);
NSLog(#"%f", self.view.bounds.size.height);
}
The bounds are before the orientation change. Thus, this only works if the transformation is 180 degrees. If I were to use didRotateFromInterfaceOrientation, the animation will be after the orientation change which looks awful.
Use willAnimateRotationToInterfaceOrientation:duration: instead. This method gets called from within the rotation animation block, and all the bounds have been set correctly at this point. Docs.
If you want it dynamic then when you initialize imageView, set the autoresizingMask property so that when the imageView's superview resizes on the rotate the margins can auto resize themselves...
imageView = //init imageView
imageView.autoresizingMask = UIViewAutoresizingFlexibleTopMargin|UIViewAutoresizingFlexibleBottomMargin|UIViewAutoresizingFlexibleLeftMargin|UIViewAutoresizingFlexibleRightMargin;
//addtional config
This means you only need to set the frame once then the imageView will always adjust itself to stay in the middle.
Check out the UIView class reference http://developer.apple.com/library/ios/ipad/#documentation/uikit/reference/uiview_class/uiview/uiview.html to see what else you can do with the autoresizingMask property
If I'm understanding you correctly, you just need to swap the X/Y coordinates and width/height in you're CGRectMake, to get your future layout for a 90 degree change. If it's 180 degree change, then it's the same as current
CGRectMake(self.view.bounds.origin.y + (self.view.bounds.size.height - image.size.height)/2 , self.view.bounds.origin.x + (self.view.bounds.size.width - image.size.width)/2, image.size.height, image.size.width);

UIScrollView: handling of dynamic content?

I've a Storyboard with a UIScrollView which contains two UILabels, a UIImageView and a UITextView. The content of the UIImageView and UITextView is dynamic and so are their height.
Currently I'm doing this inside my viewDidLoad to adjust the size of the UITextView after the dynamic text is inserted:
CGRect frame = self.textView.frame;
frame.size.height = self.textView.contentSize.height;
self.textView.frame = frame;
Is this the way to change its height?
My next problem is to set the content size for the UIScrollView, to activate the scrolling. Is there a smart way to get the height of all its content or do I have to calculate the height for each element and set the sum of this as the content size of the UIScrollView?
IF you had no space in between your objects, you could make a for loop in your scrollView.subviews and add up all the heights to set as the contentSize.
As you probably don't have everything tight together, you're probably better by getting the bottom most object and adding up it's frame.origin.y and it's frame.size.height (maybe you want to have some extra space in here, but that's up to you) and that will give you your contentSize.height to keep everything in there.