Hi in one of my application i had created a circle using drawrect method on UIView object.Now my concern i want draw a highlight border around the circle for that actually i used
myView.layer.borderWidth =3.0;
myView.layer.borderColor=[UIColor colorWithRed:myView.patternRed green:myView.patternGreen blue:myView.patternBlue alpha:1.0].CGColor;
But due to this code what is happening is a border is creating around the view and it's looks a rectangle, but i want to create a border around the circle itself. So if anyone know how to implement this functionality please let me know. Thanks in advance.
Try this
myView.layer.cornerRadius = 80.0f;
It'll curve your view into a circle.
Thanks.
you have to set some radius for the corners of that view so add this line
myView.layer.cornerRadius=20;
play with the numeric value to match your requirements
I hope it helps
This Works for me:
UIView *myView =[[UIView alloc]initWithFrame:CGRectMake(0,0,100,100)];
[self createRoundUIView:myView:80];
-(void)createRoundUIView:(UIView *)inputView sizeDiameter:(float)diameterSize;
{
CGPoint saveCenter = inputView.center;
CGRect frame = CGRectMake(inputView.frame.origin.x, inputView.frame.origin.y, diameterSize, diameterSize);
roundedView.frame = frame;
roundedView.layer.cornerRadius = diameterSize / 2.0;
roundedView.center = saveCenter;
}
Related
I have a simple rotation gesture implemented in my code, but the problem is when I rotate the image it goes off the screen/out of the view always to the right.
The image view that is being rotated center X gets off or increases (hence it going right off the screen out of the view).
I would like it to rotate around the current center, but it's changing for some reason. Any ideas what is causing this?
Code Below:
- (void)viewDidLoad
{
[super viewDidLoad];
CALayer *l = [self.viewCase layer];
[l setMasksToBounds:YES];
[l setCornerRadius:30.0];
self.imgUserPhoto.userInteractionEnabled = YES;
[self.imgUserPhoto setClipsToBounds:NO];
UIRotationGestureRecognizer *rotationRecognizer = [[UIRotationGestureRecognizer alloc] initWithTarget:self action:#selector(rotationDetected:)];
[self.view addGestureRecognizer:rotationRecognizer];
rotationRecognizer.delegate = self;
}
- (void)rotationDetected:(UIRotationGestureRecognizer *)rotationRecognizer
{
CGFloat angle = rotationRecognizer.rotation;
self.imageView.transform = CGAffineTransformRotate(self.imageView.transform, angle);
rotationRecognizer.rotation = 0.0;
}
You want to rotate the image around it's center, but that's not what it is actually happening. Rotation transforms take place around the origin. So what you have to do is to apply a translate transform first to map the origin to the center of the image, and then apply the rotation transform, like so:
self.imageView.transform = CGAffineTransformTranslate(self.imageView.transform, self.imageView.bounds.size.width/2, self.imageView.bounds.size.height/2);
Please note that after rotating you'll probably have to undo the translate transform in order to correctly draw the image.
Hope this helps
Edit:
To quickly answer your question, what you have to do to undo the Translate Transform is to subtract the same difference you add to it in the first place, for example:
// The next line will add a translate transform
self.imageView.transform = CGAffineTransformTranslate(self.imageView.transform, 10, 10);
self.imageView.transform = CGAffineTransformRotate(self.imageView.transform, radians);
// The next line will undo the translate transform
self.imageView.transform = CGAffineTransformTranslate(self.imageView.transform, -10, -10);
However, after creating this quick project I realized that when you apply a rotation transform using UIKit (like the way you're apparently doing it) the rotation actually takes place around the center. It is only when using CoreGraphics that the rotation happens around the origin. So now I'm not sure why your image goes off the screen. Anyway, take a look at the project and see if any code there helps you.
Let me know if you have any more questions.
The 'Firefox' image is drawn using UIKit. The blue rect is drawn using CoreGraphics
You aren't rotating the image around its centre. You'll need correct this manually by translating it back to the correct position
I'm having a problem with custom drawing NSView using as documentView of a NSScrollView.
Here is my drawRect: code:
- (void)drawRect:(NSRect)dirtyRect
{
[[NSColor lightGrayColor] set];
NSRectFill(self.frame); // Fill entire frame
[[NSColor grayColor] set];
[NSBezierPath setDefaultLineWidth:1];
float y = 0.0f;
while (y <= self.frame.size.height) {
[NSBezierPath strokeLineFromPoint:NSMakePoint(0.0f, y) toPoint:NSMakePoint(self.frame.size.width, y)];
y += 50.0f;
}
float x = 0.0f;
while (x <= self.frame.size.width) {
[NSBezierPath strokeLineFromPoint:NSMakePoint(x, 0.0f) toPoint:NSMakePoint(x, self.frame.size.height)];
x += 50.0f;
}
}
Everything is OK when I scroll the view rightward, but I see strange lines when I scroll the view leftward.
I think this is a cached image buffer or something but I couldn't get why this occurs because I fill a rect which covers entire frame.
What causes this problem? How can I solve it? Thanks.
I know this is an old question but I just encountered the same problem and I managed to fix it.
the drawRect method has one argument, a (CGRect) dirtyRect. My mistake was that I used the dirtyRect to check for the boundaries to draw on, just like on iOS. But I discovered that this CGRect is called 'dirty' for a reason. It specifies the region that the OS wants you to redraw. This sometimes isn't the entire frame of the NSView, but a part of it. This allows you to make really fast optimized code that does't draw more than it has to.
My solution was to ignore the dirtyRect and instead simply use self.bounds for drawing.
Basically, you're drawing on top of the old content.
So, essentially, you need to clear it somehow.
One way is
[[NSColor clearColor] set];
NSRectFill(_bounds);
You may want something more precise or not.
I have 4 views and i am drawing circles inside these views.The user is able to move these views.How can i get the position of each view relative to the window(i mean relative to 320*480)?
I want to draw and fill a polygon using the position of views.
You can use the frame property of the UIView to retrieve its location and size. See the class reference for more information:
http://developer.apple.com/library/ios/#documentation/UIKit/Reference/UIView_Class/UIView/UIView.html
Example:
... = myView.frame.origin.x; //x-coord
... = myView.frame.origin.y; //y-coord
... = myView.frame.size.width; //width
... = myView.frame.size.height; //height
You can grab the position in the following way:
CGPoint positionOfAView = view.frame.origin;
or if transforms were applied:
CGPoint positionOFAView = view.bounds.origin;
Alternatively, you may want to grab the center:
CGPoint centerOfAView = view.center;
See this answer, too.
You have posted the same question again.(your first question) Before anybody answer's this question the same way it was answered earlier. Can you please tell,
Are you drawing the Circles in the view using CoreGraphics?
When you say 4 different views, how they are managed? Are they displayed at the same time?
Are there 4 View objects added on 1 ViewController?
You can get the position using
CGRect frame = [myView frame];
But remember it will send coordinates and origin based on its parent view
And after making changes
myView.frame = frame;
Hope this helps....
If you want to just move a view (without changing it size), consider using the center property, it might be more convenient.
Here's an example, assuming your circle structure is built in a certain way :)
myView.center = CGPointMake(circle.x + circle.width/2, circle.y + circle.height/2);
I have 4 views and i am drawing circles inside these views.The user is able to move these views.How can i get the position of each view?
If your views are instance variables in your class you can use view.frame or view.center but your question is quite low on details so I'm just shooting in the dark.
CGPoint origin = view.origin;
CGPoint center = view.center;
CGRect frame = view.frame;
All these things can be used to get what you want.
I have a UIImageView that displays a bigger image. It appears to be centered, but I would like to move that image inside that UIImageView. I looked at the MoveMe sample from Apple, but I couldn't figure out how they do it. It seems that they don't even have an UIImageView for that. Any ideas?
What you need is something like (e.g. showing the 30% by 30% of the top left corner of the original image):
imageView.layer.contentsRect = CGRectMake(0.0, 0.0, 0.3, 0.3);
Description of "contentsRect":
The rectangle, in the unit coordinate space, that defines the portion of the layer’s contents that should be used.
Original Answer has been superseded by CoreAnimation in iOS4.
So as Gold Thumb says: you can do this by accessing the UIView's CALayer. Specifically its contentRect:
From the Apple Docs: The rectangle, in the unit coordinate space, that defines the portion of the layer’s contents that should be used. Animatable.
Do you want to display the image so that it is contained within the UIImageView? In that case just change the contectMode of UIImageView to UIViewContentModeScaleToFill (if aspect ratio is inconsequential) or UIViewContentModeScaleAspectFit (if you want to maintain the aspect ratio)
In IB, this can be done by setting the Mode in Inspector.
In code, it can be done as
yourImageView.contentMode = UIViewContentModeScaleToFill;
In case you want to display the large image as is inside a UIImageView, the best and easiest way to do this would be to have the image view inside a UIScrollView. That ways you will be able to zoom in and out in the image and also move it around.
Hope that helps.
It doesn't sound like the MoveMe sample does anything like what you want. The PlacardView in it is the same size as the image used. The only size change done to it is a view transform, which doesn't effect the viewport of the image. As I understand it, you have a large picture, and want to show a small viewport into it. There isn't a simple class method to do this, but there is a function that you can use to get the desired results: CGImageCreateWithImageInRect(CGImageRef, CGRect) will help you out.
Here's a short example using it:
CGImageRef imageRef = CGImageCreateWithImageInRect([largeImage CGImage], cropRect);
[UIImageView setImage:[UIImage imageWithCGImage:imageRef]];
CGImageRelease(imageRef);
Thanks a lot. I have found a pretty simple solution that looks like this:
CGRect frameRect = myImage.frame;
CGPoint rectPoint = frameRect.origin;
CGFloat newXPos = rectPoint.x - 0.5f;
myImage.frame = CGRectMake(newXPos, 0.0f, myImage.frame.size.width, myImage.frame.size.height);
I just move the frame around. It happens that portions of that frame go out of the iPhone's view port, but I hope that this won't matter much. There is a mask over it, so it doesn't look weird. The user doesn't totice how it's done.
You can accomplish the same by:
UIImageView *imgVw=[[UIImageView alloc]initwithFrame:CGRectMake(x,y,height,width)];
imgVw.image=[UIImage imageNamed:#""];
[self.view addSubView imgVw];
imgVw.contentMode = UIViewContentModeScaleToFill;
You can use NSLayoutConstraint to set the position of UIImageView , it can be relative to other elements or with respect to the frame.
Here's an example snippet:
let logo = UIImage(imageLiteralResourceName: "img")
let logoImage = UIImageView(image: logo)
logoImage.translatesAutoresizingMaskIntoConstraints = false
self.view.addSubview(logoImage)
NSLayoutConstraint.activate([logoImage.topAnchor.constraint(equalTo: view.topAnchor,constant: 30),
logoImage.centerXAnchor.constraint(equalTo: view.centerXAnchor),logoImage.widthAnchor.constraint(equalToConstant: 100),logoImage.heightAnchor.constraint(equalToConstant: 100)
])
This way you can also resize the image easily. The constant parameter represents, how far should a certain anchor be positioned relative to the specified anchor.
Consider this,
logoImage.topAnchor.constraint(equalTo: view.topAnchor,constant: 30)
The above line is setting the top anchor of the instance logoImage to be 30 (constant) below the parent view. A negative value would mean opposite direction.