It seems that libz.1.2.3.dylib is not included in iOS5 sdk. Here is simple method to fix this:

1. Open your project in XCode 4.2

2. Remove libz.1.2.3.dylib from framework

3. Add new framework libz.1.2.5

4. Run you app

It works fine. At least for me 😉

!! Enjoy !!

Some times we need to customize our table cell’s height according to text length. For long text we need to make a bigger cell and vice versa. Here is the method to do this:

1. define you table cell’s size and font:

#define CONST_Cell_height 50.0f
#define CONST_Cell_width 270.0f
#define CONST_textLabelFontSize     16
#define CONST_detailLabelFontSize   14

2. Here is the method to calculate table cell width:

– (int) heightOfCellWithTitle :(NSString*)titleText
andSubtitle:(NSString*)subtitleText
{
CGSize titleSize = {0, 0};
CGSize subtitleSize = {0, 0};

if (titleText && ![titleText isEqualToString:@””])
titleSize = [titleText sizeWithFont:[UIFont boldSystemFontOfSize:16]
constrainedToSize:CGSizeMake(CONST_Cell_width, 4000)
lineBreakMode:UILineBreakModeWordWrap];

if (subtitleText && ![subtitleText isEqualToString:@””])
subtitleSize = [subtitleText sizeWithFont:[UIFont systemFontOfSize:14]
constrainedToSize:CGSizeMake(CONST_Cell_width, 4000)
lineBreakMode:UILineBreakModeWordWrap];

descriptionLabelHeight = subtitleSize.height;

return titleSize.height + subtitleSize.height;
}

3. Use this in your table height for row:

– (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {

NSString *title = @”Yor cell title”;
NSString *subtitle =@”Your cell subtitle”;

int height =  “some constant” + [self heightOfCellWithTitle:title andSubtitle:subtitle]; // some constant is used to adjust cell height. may be zero.

return (height < CONST_Cell_height ? CONST_Cell_height : height);

}

it will resize the table cell according to text size.

!! Enjoy !!

Here is a small core graphics method for masking of images:

– (UIImage*) maskImage:(UIImage *)image withMask:(UIImage *)maskImage {

CGContextRef mainViewContentContext;
CGColorSpaceRef colorSpace;

colorSpace = CGColorSpaceCreateDeviceRGB();

// create a bitmap graphics context the size of the image
mainViewContentContext = CGBitmapContextCreate (NULL, image.size.width, image.size.height, 8, 0, colorSpace, kCGImageAlphaPremultipliedLast);

// free the rgb colorspace
CGColorSpaceRelease(colorSpace);

CGImageRef maskingImage = [maskImage CGImage];
CGContextClipToMask(mainViewContentContext, CGRectMake(0, 0, maskImage.size.width, maskImage.size.height), maskingImage);
CGContextDrawImage(mainViewContentContext, CGRectMake(0, 0, image.size.width, image.size.height), self.CGImage);

// Create CGImageRef of the main view bitmap content, and then
// release that bitmap context
CGImageRef mainViewContentBitmapContext = CGBitmapContextCreateImage(mainViewContentContext);

// convert the finished resized image to a UIImage
UIImage *theImage = [UIImage imageWithCGImage:mainViewContentBitmapContext];
// image is retained by the property setting above, so we can
// release the original

CGContextRelease(mainViewContentContext);
CGImageRelease(mainViewContentBitmapContext);
maskingImage = nil;
CGImageRelease(maskingImage);
// return the image
return theImage;

}

For more detail about masking please checkout Quartz 2D developer guide:

http://developer.apple.com/library/mac/#documentation/GraphicsImaging/Conceptual/drawingwithquartz2d/dq_images/dq_images.html

!! Enjoy !!

Sometimes when we are zooming image by using Pinch Gesture, we can’t handle the size of zooming. Here is a small code to do this.

The code below assumes there is an instance variable CGFloat lastScale and that a view has been set for the UIPinchGestureRecognizer.

When you add Tab Bar in your iPhone project, by default its background color is black and selection color is blue. But if you need to change it add these code in your project file RootViewController-

// RootViewController.h file

@interface UITabBar (ColorExtensions)

– (void)recolorItemsWithColor:(UIColor *)color shadowColor:(UIColor *)shadowColor shadowOffset:(CGSize)shadowOffset shadowBlur:(CGFloat)shadowBlur;

@end

@interface UITabBarItem (Private)

@property(retain, nonatomic) UIImage *selectedImage;

– (void)_updateView;

@end

//RootViewController.m file

@implementation UITabBar (ColorExtensions)

– (void)recolorItemsWithColor:(UIColor *)color shadowColor:(UIColor *)shadowColor shadowOffset:(CGSize)shadowOffset shadowBlur:(CGFloat)shadowBlur

{

CGColorRef cgColor = [color CGColor];

CGColorRef cgShadowColor = [shadowColor CGColor];

for (UITabBarItem *item in [self items])

if ([item respondsToSelector:@selector(selectedImage)] &&

[item respondsToSelector:@selector(setSelectedImage:)] &&

[item respondsToSelector:@selector(_updateView)])

{

CGRect contextRect;

contextRect.origin.x = 0.0f;

contextRect.origin.y = 0.0f;

contextRect.size = [[item selectedImage] size];

// Retrieve source image and begin image context

UIImage *itemImage = [item image];

CGSize itemImageSize = [itemImage size];

CGPoint itemImagePosition;

itemImagePosition.x = ceilf((contextRect.size.width – itemImageSize.width) / 2);

itemImagePosition.y = ceilf((contextRect.size.height – itemImageSize.height) / 2);

UIGraphicsBeginImageContext(contextRect.size);

CGContextRef c = UIGraphicsGetCurrentContext();

// Setup shadow

CGContextSetShadowWithColor(c, shadowOffset, shadowBlur, cgShadowColor);

// Setup transparency layer and clip to mask

CGContextBeginTransparencyLayer(c, NULL);

CGContextScaleCTM(c, 1.0, -1.0);

CGContextClipToMask(c, CGRectMake(itemImagePosition.x, -itemImagePosition.y, itemImageSize.width, -itemImageSize.height), [itemImage CGImage]);

// Fill and end the transparency layer

CGContextSetFillColorWithColor(c, cgColor);

contextRect.size.height = -contextRect.size.height;

CGContextFillRect(c, contextRect);

CGContextEndTransparencyLayer(c);

// Set selected image and end context

[item setSelectedImage:UIGraphicsGetImageFromCurrentImageContext()];

UIGraphicsEndImageContext();

// Update the view

[item _updateView];

}

}

@end

// in ViewDidLoad{

// Give the selection color and its shadow

[[[self tabBarController] tabBar] recolorItemsWithColor:[UIColor whiteColor] shadowColor:[UIColor blackColor] shadowOffset:CGSizeMake(0.0f, -1.0f) shadowBlur:3.0f];

}

It’s works great friends 🙂

!! Enjoy !!