Interface Builder vs. What's Displayed on iPhone - iphone

Hello and thanks for giving this question a gander.
It seems that PNG files that I drag/drop into IB do not display in the same manner that they are shown in the iPhone simulator. What gives? For example, if I want to drop in a PNG with rounded corners, IB shows hard rectangular corners but when I build to the simulator, I see the rounded edges.
I don't understand the purpose of IB for UI if I can't accurately reflect what will be shown for that view.

Can you verify that the PNG files are saved with a pixel density of 72dpi? Also, what type of UI element are you using? (UIButton, UIImageView, etc). It would help if you could post a sample image.

Related

rectangular uibutton from a single square image

From inspecting latest facebook and expedia iphone app, I can see the developers have used a single squared image which gets scaled up in run time into rectangular shape.
Can anyone share some code on how to do this programmatically in conjunction with the square image?
You are probably looking for this . Here's another one: Stretchable Images and Buttons

iphone large icon 512x512 with border glitch?

I just uploaded my first iPhone app. The app icon has a border, sort of like the "settings" icon. However, when I upload my large icon in iTunes connect, there are some weird white edges in the corners. It appears that they might use a smaller corner radius or something. How can I make sure it will display correctly on the apple store?
The image is a jpeg with no transparency.
Thanks for the help!
What's happening is the appstore is expecting a purely square 512x512 image. It then masks it to have rounded corners and then adds a drop shadow automatically.
If you want it to have a specific border like what you've designed you need to match their rounding exactly.
If you search around. there are PSD templates available that will help you design it (i.e. they have the exact mask that itunes uses).
Here's an example: http://www.pixelresort.com/blog/app-icon-template/
Another technique which can work really well is leaving the outer part of the icon square — in your case, the dark brown outer border would extend to the edge of the canvas – and let the roundrect mask handle the corners for you. There's a bit more info in this excellent blog post: All the sizes of iOS app icons
You'd still get the border effect, but let it be cut cleanly by the mask rather than by your icon's transparency.
I believe this to be a bug with iTunes Connect. I've seen the same problem, but it only appears on the Versions summary screen.
I've seen this when uploading a square icon. For example:
In summary, don't worry about it. Your icon should still show up correctly in the iTunes Store and on the Devices themselves. If your icon looked clean in the iOS Simulator and on your device, you're good to go.

Image "frame/window" on iphone

I have numerous photos in portrait and landscape format. I want to be able to display a "crop" of the photo in a UIImageView on the iphone. If the picture is in landscape format I want it to resize to fit the frame, if it is in portrait format I need it to resize to fit the width, and then be cropped at the top and bottom. As if there is a "window" over the image - so it looks like a landscape picture.
It would be even better if this could be a UIButton - although I am aware that I can use touchesBegan and such on images to make it behave like a button if needs be.
Thanks for any help you can give me.
Thanks
Tom
In an ImageView, you can change the View Mode to Aspect Fill. It will give you the right scaling/cropping you want.
For interactions, you can use a Custom button with no drawing at all (no Title, no Image, no Background) with the same size as your ImageView. That would be safe with regards to the image aspect. I've tried similar stuff using the button's Background or Image properties, it can have some undesired effects (I've ran into a resizing issue on iOS 3.1.3 for instance).
1°) To Crop the Image, try to add a method to UIImage class to do it (you can google it without problem, or even on StackOverFlow)
2°) To add a "window" over your image, just add an UIImageView over your image wich has transparency. It should work ;-)
3°) To know when an image is touched, you can use "touchesBegan" to detect which image were selected. But I think it's the last of your problems ^^
What you cant to achieve isn't so hard, just to it step by step !
If you want more help in one step, say it. But I can't code it all for you ;-)
Good Luck

iPhone UIImage overlap render bug

I've come across a strange render bug on iPhone OS 3.0...
I have two images. One is a non-transparent PNG that is predominately black with a white gradient fading upward.
The second is a transparent PNG with translucent clouds.
When I overlay the two using UIImageView, the intersection of the clouds and white gradient triggers a render bug that causes a rather odd looking graphical glitch that removes all opacity from the image on top (in this case the clouds), and causes the glitched portion of the image to render on top of all layers in the current view (including ones it is technically underneath).
It only occurs at the intersection of the two portions of the images. So typically only a very small block is experiencing the error while the rest of the images render normally.
Has anyone seen this and does anyone have a fix? I want to check before I move on to Core Animation which will hopefully address the problem (since I imagine that CA or even OpenGL is more apt to handle overlapping alpha channels).
Screenshot found here:
http://www.jasconi.us/glitch.jpg
You can see the intersect of the two images at the lower right.
From your description, this seems to be a bug in Apple's code. I would report it to Apple and wait for a fix.
In the meantime, you can try to implement the same functionality in Core Animation or OpenGL in the hope that the bug is in the higher-level UIImageView, but since the UIImageView itself uses Core Animation, it's possible that this bug is simply unavoidable until it's fixed.
I assume you're displaying them using UIImageView? If so, have you set opaque to NO on the transparent view?

Generating icons for iPhone UITabBar

I’ve been busy working on the graphics for my iPhone application. I started working on generating icons for my UITabBar and ran into lots of problems. How do you create these icons?
I created this solution:
http://www.nailrails.com/?p=46
Are there any shortcomings to this approach? It seemed to work for the few icons I created...
Apple's guidelines can be found at http://developer.apple.com/library/ios/#documentation/UserExperience/Conceptual/MobileHIG/IconsImages/IconsImages.html#//apple_ref/doc/uid/TP40006556-CH14-SW1
The docs are pretty straightforward-- alpha is all that matters when the image gets loaded by the toolbar, meaning that anything that's not at least semitransparent will render in the same opaque shade. As for how I do that, I mainly use Adobe tools. Fireworks is my preferred tool but Photoshop's also more than up to it. Another one I've had good results with is Acorn, which is frankly a lot cheaper while being more than sophisticated enough for this kind of work. I'm not really a graphic designer but a certain familiarity with this kind of stuff goes with the job.
I have an article up on my site that shows how to use OmniGraffle with a template I use to create great iPhone toolbar icons in minutes:
http://steveweller.com/articles/toolbar-icons/
The template sets up a grid to work to that corresponds to one square for each pixel. You draw your icon in white on top of the black template background and then export as a PDF exactly the right area to match the icon size you need (typically 21 pixels high). Then you reimport the PDF, resize it to the final icon size (21 pixels again), and export as PNG. The template does nothing magical; it just provides an already set up working area and helps you get the final PNG right every time to the scale is correct.
You could use the same technique in Acorn or any other app that supports PDF export and layers.
(I use Gimp. Assume your icon layer already has alpha channel.)
Right click the layer, then add layer mask.
Done with option "transfer alpha channel of layer" chosen.
Select the whole layer (but not layer mask), and clear it with pure white.
Resize image to Apple-suggested size, and export it as png file.
You may also paint directly on the layer mask.