I am fairly new in iOS programming and I am creating my first app.
I have been trying to use the following code to change the navigation bar background image (this is using the new iOS 5 method):
[self.navigationController.navigationBar setBackgroundImage:[UIImage imageNamed:#"gradientBackgroundPlain.png"] forBarMetrics: UIBarMetricsDefault];
It works fine, but my image is 640 x 88 and it looks too big for the bar. It's like the system doesn't want to scale it, or do I need to do it manually? If I scale the image and create a smaller one it looks pixelated in the retina display.
Any thoughts on this?
Any help or response will be appreciated.
Thanks,
Jorge.-
Your image gradientBackgroundPlain.png should be 320x44, and create a second image named gradientBackgroundPlain#2x.png with a size of 640x88. Include the #2x image in your bundle, but continue to specify gradientBackgroundPlain.png for the name of the image. The platform automatically chooses the correct size image for use depending on whether there is a retina display present or not.
Related
My question is, why does the iPad preview use a different image than the storyboard for wRegular hAny?
I'm trying to set up a universal app with a menu that will use larger buttons for iPad. In the asset catalog, I've specified the standard image size for wAny x hAny, and loaded a larger image for wRegular x hAny.
The story board looks fine for all size classes, with the wRegular x hAny using the iPad image, and everything else using the iPhone image. But the previews all use the iPhone image, including the iPad preview, despite the storyboards showing the correct images. In the screen shots below, the story board is shown to the left, preview to the right.
Can someone tell me what I'm doing wrong here? I'm trying to avoid using explicit image sizes for each class - is that what I should be doing?
Any help would be greatly appreciated. I've read everything I can on using different image sizes, and still cannot figure this out.
enter code here
You can't have a different images by size class for the same button in Interface Builder. It looks to me like you set the image of the button to be the iPad one first in Regular/Any, then set the iPhone one afterward in Any/Any which changed what you did in Regular/Any.
In this image, see how the Font has a + symbol to the left of it, but Image doesn't? That's for specifying the value per size class. Since Image doesn't have that, it's not a value saved for the specific size class.
Currently I am designing the UITabbar of my App. I created a Photoshop layout for the Tabbar, it is 84px high and 640px wide. Is it the right way to create one image with the size of 84x640 and one with the size 320x42. And then name the larger image #2x.png.
I am struggling at this point, because when I log the width of the UITabbar it says 320.00, but I am using the Iphone 3.5inch retina simulator.
Any tips for me to realize the tabbar?
Yes. You should have two images. One for normal displays and one for retina.
Xcode works with point, not pixels, so the width will always be 320.
In the case of retina display one point is 2x2 pixels and in normal mode it is 1x1.
by the way, I think the height for the tab bar should be 320x49 for normal and 640x98 for retina.
the retina image should have the same name as the normal one with the #2x at the end
Example:
normal: image.png
retina: image#2x.png
You confused "Points" with "Pixels". The Points are resolution independent. You can normally check your scale factor by calling contentScaleFactor on your UIView.
It should say 2.0 for retina, and 1.0 for non retina.
I have a Titanium app where I am using the same ImageView for alot of different images. I am changing the image in the image view by setting it's image property.
The problem is some of the images are not showing at their full size sometimes, it is kinda random, but sometimes they show full size sometimes not.
I have width and height set to "auto" on the image view.
Anyone come across this issue.
A potentially more reliable way would be too dynamically resize the image before handing it off to the ImageView by using Titanium.Blob.imageAsReized.
Try to integrate this in your code, first you have to load the image as a blob though.
// Get the blob of your image first, then call this method
imageView.image = imageBlob.imageAsResized(newWidth, newHeight);
I am a bit confused on managing the different sized images with retina and non-retina displays.
I add a custom button in Storyboard and add some text and then add the backgroundimage, which is a vector done in Illustrator (Width: 630 / Height:130):
UIImage *img = [UIImage imageNamed:#"iPad1_orange_button.png"];
[myButton setBackgroundImage:img forState:UIControlStateNormal];
the button shows up:
...the button comes out very small.
I have another image with the #2x for retina but that comes out the same size.
My question is how to manage the sizes of the buttons in regards to image size. DO i need to set the size of the button manually?
Also, when i create a button in Illustrator with the same pixel size as the button i use in XCODE and export it as .png, add it to XCODE and drag it into Storyboard it comes out very large.
Just a quick clarification:
The storyboard dimensions are NOT in pixels.
An iPhone 4S has 640x960(x,y) # 326ppi. xCode dimensions are 320by460(x,y). Just take the numbers and convert em to get the appropriate pixel sizes.
IE: If you want a button that that is 100 wide and 100 tall in storyboard you'd to create an image 100*(640/320) px wide and 100*(960/460) px tall (I believe my math is right...).
Depending on what you're building for you'd need different images to cater to the different devices.
On another note, the term retina display doesn't designate a clear-cut standard of px by px. If I recall correctly it's a term Apple coined that basically means that a screen has enough px that the human eye (hence retina) would not be able to see the jaggies.
Similar to Intel's coining of the term Ultrabook; no REAL spec floor/ceiling just a marketing ploy.
Think of dimensions and what you would consider a pixel to be a "density independent pixel". You are always working in the original size when it comes to position and size but it is up to the operating system to handle the different resolutions for you. For now we have the original size and Retina which is X2 the density but this could change. You never need to manually change the resolution for the given device.
This is simple:
make the button frame the size of the normal res image
when you load the image with UIImage imageNamed: do it like this
UIImage *img = [UIImage imageNamed:#"iPad1_orange_button"];
*Note I removed the file extension (.png) - this instructs UIImage to select the resolution appropriate version, the regular or the #2x. iOS will show the 2x version of the image in the same frame size as the normal res image. Pretty simple.
I am about to launch a new app and would lik eto increase quality of the graphics. In my case the graphics is the logo and the custom buttons. I do not know if this impact Core Plot but that is also part of the package.
There is quite a few posts about this but there are still things i do not fully understand.
I am reading this quote from "amattn":
It's trivial:
1.Only include #2x images in your project.
2.Make sure those images have the #2x suffix.
The system will automatically downscale for non-retina devices.
The only exception is if you are doing manual, low level Core Graphics drawing.
You need to adjust the scale if so. 99.9% though, you don't have to worry about this.
From this post: Automatic resizing for 'non-retina' image versions
My question in regards to this is:
1. Should i do the testing on retina simulator only, as if i place a #2 grapic on
non-retina it will be too big? ...or is there an other way of doing it?
2. Should i always use a ImageView or is it OK to drag the image on the screen,
this is the logo i am talking about?
3. What about custom made buttons with images, how should i do with those?
4. What is the normal process to manage the different screen sizes, do people
add images for all displays or using this type of process?
Should i do the testing on retina simulator only, as if i place a #2 grapic on non-retina it will be too big? ...or is there an other
way of doing it?
It doesn't really matter which simulator you test on because as long as your non-retina and retina graphics are named correctly (image and image#2x) the correct image will be displayed automatically.
Should i always use a ImageView or is it OK to drag the image on the screen, this is the logo i am talking about?
When you drag and image from the project directly onto a view in interface builder you don't really see it happen but it has automatically created and image view which is containing the image your dropped in.
What about custom made buttons with images, how should i do with those?
[myButton setImage:[UIImage imageNamed:#"myFileName"]];
As shown in the above code you should always use the non-retina fle name when you reference the image a UI element should use. That was if iOS detects the device is retina it can automatically use the #2x version in its place.
What is the normal process to manage the different screen sizes, do people add images for all displays or using this type of process?
Yes, including multiple image resolutions common practice and is required for iPhone apps (not sure about iPad) to include both retina and non-retina images. But regardless of the requirements, you should definitely support both device resolutions to keep your customers happy!