Custom UIButton hard to press - iphone

If I add a basic UIButton all is well, they are always easy to press every time. However, when I make a custom version using my own .png it becomes hard to trigger every time.
My custom button is a little smaller 32x32 and is mostly transparent. Could it simply be that its smaller, could the transparency be a problem..?
many thanks for any thoughts..

Maybe it is because it's smaller than 32x32, try making your transparency layer a little bigger, say 40x40 to have a bigger hit area. I mean use a bigger PNG :)

Check whether you have overhided any touches method and not called super in it...
Keep the frame of the view to 40*40 and clear the background color then set the image which is 32*32... It will work correctly

Related

Make fix size round button as image in iphone sdk

I am developing an application in which I need to round button as image (as I uploaded).
It Show two corner are straight and the rest is in round shape. I tried withmybutton.layer.cornerRadius but make round whole image. I also tried to just make custom button but it leave extra space in button around image i need to fix size button as image show.
Please help me. Thanks in advance. Happy Day.
Here is a one good tutorial on this:
http://iphonedevelopment.blogspot.in/2010/03/irregularly-shaped-uibuttons.html
you can download code from here
https://github.com/ole/OBShapedButton
Hope this helps
An alternate but not really a good one first add an imageView add this particular image over it than add an custom invisible button over the image by adjusting size of the button it will not cover the whole image though but still it will work fine...actually i did use this approach in one of my app :p
OBShapedButton might help. It's an open source UIButton subclass optimized for non-rectangular button shapes. If it still doesn't work, making your own buttons isn't that difficult either. Use a UIView and handle touches within the view. For eg, in touchesMoved:, set the active image and in touchesEnded:, handle the click event!

Why does my text look so bad in my ios App?

I have a uiscrollview that has a custom child view that contains text and images.
The text items are UILabels. I have attached an image representing the quality issue:
Do you guys think it might be worth a shot to draw the text, then convert to a uiimage and display that instead? Maybe it would scale better? Or perhaps there is a way to smooth the text?
There's no reason to expect that you're going to draw the text better than UILabel does. Your picture is very hard to make out, but here's what you want to look at:
Are you just adding a UILabel to the UIScrollView's contentView, or are you doing something else fancier. That "something else fancier" could easily be the problem.
Make sure you're drawing on pixel-aligned boundaries. The easiest way is to make sure the origin of your UILabel is integral (not a fraction). On a retina display, you can get away with half-points, but it's usually easier just to make everything integers.
I thinks it is the position issue. I bet you set the x or y value to float value like 12.3 or 12.5 .
What I have done now is I have created a uiimage version of my text and am showing that now instead of the uilabels, the quality is soo much better, you can really see the difference when you are looking at it scaled up on the ipad, it must just do a better job scaling images then text?
Before:
After:
The above images show how the text renders on the ipad with my app scaled up, before and after my change.

UI Button with Image Smaller than Touchable Area

I've not much response so am adding some more info.
My buttons are not rectangular, nor organised in a grid so I need a way of creating what looks like a button (and shows that it has been pressed visually, as per a standard UIButton) but where the touchable area is different to the image area.
I am using a transparent PNG and that element works fine. I've added the buttons in Interface Builder and am wondering if that is the problem.
However, if I change imageEdgeInsets, it distorts the image display, which is obviously not what I want.
Bizarrely, if I increase the dimemsions of the button, it doesn't change the image, but if I decrease them it does.
I have tried different combinations of mode (scale to fill etc), but to no avail.
I am aware that there is an image and background image property, but in IB there is only one.
Essentially, I don't understand how the geometry works and the Apple documentation doesn't seem to help.
Surely, I can't be the only person to try to do this. Any help would be warmly welcomed.
Many thanks,
Chris.
Try setting the buttons setting to Aspect Fit. This will fill the button with your image so a smaller image than the button size would leave the space around the image.
Also set the button type to custom.
In the end, I stumbled across Ole Begemann's Non-rectangular buttons class. It just does what I need - to be able to create buttons where the touchable area follows the visible element of a non rectangular image.
#Helium3 - thanks - that allowed me to use a larger touch area, bit not a smaller one.

Tinting iPhone application screen red

I'm trying to place a red tint on all the screens of my iPhone application. I've experimented on a bitmap and found I get the effect I want by compositing a dark red color onto the screen image using Multiply (kCGBlendModeMultiply).
So the question is how to efficiently do this in real time on the iPhone?
One dumb way might be to grab a bitmap of the current screen, composite into the bitmap and then write the composited bitmap back to the screen. This seems like it would almost certainly be too slow. In addition, I need some way of knowing when part of the screen has been redrawn so I can update the tinting.
I can almost get the effect I want by putting a red, translucent, fullscreen UIView above everything. That tints everything red within further intervention on my part, but the effect is much "muddier" than results from the composite.
So do any wizards out there know of some mechanism I can use to automatically composite the red over the app in similar fashion to what the translucent red UIView does?
I managed to somewhat make this work but with some side-effects:
I setup a UIView on top of all my app-views (attached to the window) which is not userInteractionEnabled and which is opaque
This UIView carries some custom drawRect-method which first fills the complete area with red color and then after having made a "screenshot" of my window-viewhierarchy I am rendering this image with
CGContextSetBlendMode( c, kCGBlendModeMultiply);
to the UIView.
To constantly update this UIView to the current state of the apps UIViews I constantly produce "screenshots" and render them as fast as possible.
I setup an NSTimer which is doing this snapshotting/rendering in a defined frequency and which is added to the the NSRunLoop for "Tracking".
RESULT: some really laggy response from the UI with several fancy effects, but still usable though if you do not set the frequency of snapshotting/rendering to high.
See screenshot here...
The result looks okay, but the usability really suffers a lot. I had a look at the OpenGL-examples before trying this aproach, but OpenGL is a whole lot of different (mostly C) code which seems to be very near to the hardware and which gives you a real headache.
So, the described approach is what I will shoot for with my next app. I hope Apple accepts it even though it degrades UXP during nightvision mode. They should simply make CALayer filter-backed then my problem will definitely be solved a whole lot better and performing nicely.
You could try this: subclass UIView. Add code to -drawRect method to draw the overlay. Make your UIView subclass pose as UIView everywhere in your app with
class_poseAs ([CustomUIView class], [UIView class]);

Changing color of part of an image

I have a png image file that is partly opaque and partly transparent. I display it in a UIImageView as a mask of sorts over another UIImageView layered behind it (as a sibling subview of a common superview). It gives me perfect borders around something painted using a finger on the lower UIImageView in my stack of UIImageViews. Perhaps there are better ways to do this, but I am new-ish, and this is the best way I came up with thus far. None the less, my app is in the App Store and now I want to enhance it to provide more images to use as the mask of sorts over the finger painting. But I don't want to bloat my bundle size by adding more static mask images as I did for the initial implementation. Not to mention I don't want to spend lots of time in photoshop making 100 masks. I'd rather programmatically change the color of the mask, without affecting the clear portion in the middle, which is not a simple regtangle or circle, but rather a complex shape. So my question is this: How can I change the colored portion of my loaded image without affecting the clear color portion in the middle? Is there a reasonably easy way to do this? Essentially I want to do what is described in this post (How would I tint an image programmatically on the iPhone?) without affecting the clear portion of my image. Thanks for any insights.
Have a look at the Tinted Image sample project. Try out the different modes until you get the effect you want.