I have been battling this problem for a bit, I want to display a png on a UIButton, but for some reason the image ends up being very blurry both in the simulator and on a physical device. I have tried using all different sized images, all at 326 ppi (verified in xcode), but none have looked correct. I have also tried resizing the image in my app using UIGraphics but the problem persists. Here is the code which sets up the button:
//MIRROR BUTTON
_mirrorButton = [UIButton buttonWithType:UIButtonTypeCustom];
//_mirrorButton.frame = CGRectMake(buttonWidth, 0.0f, buttonWidth, buttonHeight);
_mirrorButton.frame = CGRectMake(64, 0, 64, 50);
UIImage *mirrorImage;
_mirrorButton.backgroundColor = [MessageView getUserColor];
mirrorImage = [UIImage imageNamed:#"mirror.png"];
[_mirrorButton setImage:mirrorImage forState:UIControlStateNormal];
[_mirrorButton addTarget:self action:#selector(mirrorPressed) forControlEvents:UIControlEventTouchUpInside];
[self addSubview:_mirrorButton];
Both the UIButton and the image are supposed to have a height of 50 pixels. My UIButton's frame is integral, and the image even has an even pixel width and height (someone said this would help with the centering). Any incite would be much appreciated. Thanks.
From what im reading I presume you might be confusing 50 pixels with 50 points.
The frames in general are measured in points and not in pixels, you can see the difference HERE
So basically, if you use a 50 points high frame, in devices with retina screen you will need an image with 100px high, and then it shouldn't look blurry anymore
Related
I have a UIButton backgroundImage that I use to display a weather condition image when the loading is complete. I also create a UIImageView that replaces the UIButton to animate a series of images as a progress indicator.
My question: How can fix this animated UIImageView x-axis misalignment across multiple screen sizes?
Here's what the sequence looks like on 4.7" iPhone, the red box indicates the image I'm talking about:
First, the UIImageView animating as a progress indicator (imagine it spinning, alignment is correct)
Second, the download complete, the progress indicator replaced by a UIButton with a backgroundImage:
Third, the UIImageView animating on 4" iPhone (note misalignment on x-axis):
Fourth, the download complete, UIButton replaces it, aligned correctly:
Here's how the UIImageView *progressIndicator is configured.
Note that conditionButton is the UIButton with backgroundImage of the weather condition:
self.progressIndicator = [[UIImageView alloc] initWithFrame:self.conditionButton.frame];
self.progressIndicator.contentMode = UIViewContentModeCenter;
self.progressIndicator.animationImages = #[...long series of images...];
self.progressIndicator.animationDuration = 0.5f;
[self.conditionButton setBackgroundImage:[UIImage imageNamed:#"empty.png"] forState:UIControlStateNormal];
[self.progressIndicator startAnimating];
[self.view addSubview:self.progressIndicator];
I'm pretty sure the issue is with
self.progressIndicator = [[UIImageView alloc] initWithFrame:self.conditionButton.frame];
But I'm not sure how to resolve this.
The same problem occurs when I switch to 5.5" iPhone. I have no Auto Layout warnings, and the constraints that apply to the conditionButton are:
Align Center X to superview
Width = 94
Height = 94
Bottom and Top space to nearest neighbor = default
Any help would be greatly appreciated!
This how I add an image:
UIImageView *imageHolder = [[UIImageView alloc] initWithFrame:
CGRectMake((self.view.frame.size.width/2) - (290/2),(self.view.frame.size.height) - (140 * 1.8), 290, 140)];
UIImage *image = [UIImage imageNamed:#"no-pins.png"];
imageHolder.image = image;
imageHolder.contentMode = UIViewContentModeScaleAspectFit;
// optional:
// [imageHolder sizeToFit];
[self.view addSubview:imageHolder];
The size of the image (retina version) is exactly the same size as in CGRectMake above. However the image is a little blurred. I only can reduce the blur when I edit the image and give it a higher resolution in photoshop.
But images that I add through storyboard are all fine in quality. Any ideas what might be wrong?
For retina graphics, the image size should be twice the size of the frame of the image view. This allows the image to use a scale of 2 to take advantage of the retina screen capability. So, you should have one image of size 290x140 (if you are supporting non-retina devices) and one image of size 580x280 (this is the #2x image).
The frame of the view is the description of the position and size of the view within the view hierarchy (in terms of the superview coordinate system). If you have fractional values in the frame size or position you can get 'blurring' effects.
This is the first time I have ever designed an iOS app so I want to make sure I understand this behavior correctly.
I designed a custom bar button icon for a navigation bar in Photoshop. The final image that I saved in Photoshop was 102 x 45, and yes I realize that these dimensions are bigger than the recommended 44x44 in the iOS 7 design guidelines.
Anyways, I placed my image into the asset folder, and then programmatically set the bar button item with the following code:
UIImage* firstButtonImage = [UIImage imageNamed:#"loginbutton1"];
CGRect frame = CGRectMake(0, 0, 102, 45);
UIButton * someButton = [[UIButton alloc] initWithFrame:frame];
[someButton setBackgroundImage:firstButtonImage forState:UIControlStateNormal];
[someButton addTarget:self action:#selector(didTapLoginButton:)
forControlEvents:UIControlEventTouchUpInside];
self.rightBarButton = [[UIBarButtonItem alloc] initWithCustomView:someButton];
self.navItem.rightBarButtonItem = self.rightBarButton;
As you can see I set the frame's width and height to the exact size of the image. When I first ran the app, I didn't like the image and thought it was too big. So I changed the width and height parameters in this statement:
CGRect frame = CGRectMake(0, 0, 70, 30);
And now the image looks perfect on the iPhone screen. This is on an iPhone 4s.
So my main question is, what is actually happening when I change the frame size? Since the frame is now smaller than the actual image size, does the image just get scaled down automatically to fit inside the frame?
Yes the image get scaled because you are using backgroundImage (not Image). Both images have different behaviors.
Check the Xcode Interface Builder, you can see there, that you can set two images: Image and Background. Background is the UIImage that get scaled for the whole frame of the UIButton.
The UIButton Class Reference allows you to access the imageView of the image (not theimageView of the backgroundImage)
Because you have access to the imageView, you can change the mode of the image with:
[[someButton imageView] setContentMode:UIViewContentModeBottomLeft];
In UIView Class Reference you can check all the UIViewContentModes provided by Apple.
You can check that changing a little bit your code:
[someButton setImage:firstButtonImage forState:UIControlStateNormal];
[[someButton imageView] setContentMode:UIViewContentModeBottomRight];
In my application, i need the user to take a snap of only a 10 letter word (using overlay, which should be right in the centre of the screen of the UIImagePicker), and then in need to show him that image (only the part of the image covered by that rectangle). So, I need to crop that image according to the overlay.
Here, i have taken a picture using UIImagePickerControl. Now, i want to see the dimensions of the image that i have taken..
UIImage *imageToprocess = [info objectForKey:UIImagePickerControllerOriginalImage];
NSLog(#"image width %f", imageToprocess.size.width);
NSLog(#"image height %f", imageToprocess.size.height);
I see the following result on console.. But how is this possible. the dimensions of the image is exceeding the dimension of the iPhone screen size.. (which is 320, 568)
UsingTesseractOCR[524:60b] image width 2448.000000
2013-12-17 16:02:18.962 UsingTesseractOCR[524:60b] image height 3264.000000
Can anybody help me out here?? I have gone through several questions here, but did not understand how to do it.
Please help..
Refer this sample code for image capturing and cropping.
https://github.com/kishikawakatsumi/CropImageSample
For creating overlay, first create a custom view (of full dimensions of camera preview) and add an transparent image with just a rectangle in its background. use this view as overlay view.
myview =[[UIImageView alloc]init];
myview.frame=CGRectMake(0, 0, 320, 431);
// why 431? bcoz height = height of device - height of tabbar present in the
bottom for camera controls of picker
//for iphone 4 ,480-49
myview.backgroundColor =[UIColor clearColor];
myview.opaque = NO;
myview.image =[UIImage imageNamed:#"A45Box.png"];
myview.userInteractionEnabled =YES;
note that you create a background image appropriately (means dimensions). You can also draw rectangle programmatically but this is much easy way.
Secondly, talking about your cropping issue, you have to get your hands dirty....Try these links for help
https://github.com/iosdeveloper/ImageCropper
https://github.com/barrettj/BJImageCropper
https://github.com/ardalahmet/SSPhotoCropperViewController
Is it possible to create a properly aligned UIImageView that has a resizable image?
I tried everything (e.g. images power of two, etc) and cannot make it work.
The coordinates of the UIImageView are:
po _Background
(UIImageView *) $1 = 0x14c42bd0
<UIImageView: 0x14c42bd0;
frame = (16 38; 992 672);
opaque = NO;
autoresize = LM+RM+TM+BM;
userInteractionEnabled = NO;
layer = <CALayer: 0x14c42ba0>> - (null)
The UIImage itself is 96x96 (retina, i.e. png is 192x192 with a scale of 2). The resizable UIImage is created using:
UIEdgeInsets edgeInsets = UIEdgeInsetsMake(32, 32, 32, 32);
UIImage* resizableImage = [originalImage resizableImageWithCapInsets:edgeInsets];
[_Background setImage:resizableImage];
When turning on 'Color misaligned images' in the simulator the UIImageView _Background is highlighted with yellow. Removing its UIImage in the debugger:
[_Background setImage:nil];
removes the yellow highlight, i.e. no image -> no mis-alignment.
Anyone knows what is going on and how I can make sure it aligns?
thanks.
According to this answer: What does yellow tinting represent when using "color misaligned images" on iPhone/iOS, the yellow highlight indicates the image is stretched. Since that's what you're asking for with the resizable image, it makes sense that it's always the case.