Notes of a Developer

Sample
+ (UIImage*)greenBubble
{
    if (sGreenBubble == nil) {
        UIImage *i = [UIImage imageNamed:@"Balloon_1.png"];
        sGreenBubble = [[i stretchableImageWithLeftCapWidth:15 topCapHeight:13] retain];
    }
    return sGreenBubble;
}
 
+ (UIImage*)grayBubble
{
    if (sGrayBubble == nil) {
        UIImage *i = [UIImage imageNamed:@"Balloon_2.png"];
        sGrayBubble = [[i stretchableImageWithLeftCapWidth:21 topCapHeight:13] retain];
    [...]

Step by step for starter developers…
1. Create a project in xCode with name “DragAndDrop” or any else…2. Add an element “NSImageView” on main view in the MainMenu.xib

Hi there! We are a group of iPhone / Android developers who have developed a suite of web services to assist us and other developers in building great apps.
After numerous projects we have become tired of having to set up the server scripts to do all the same things for different clients. Most of the [...]

Presented simple and nice solution for radio buttons, based on the UIButton.
Add buttons on view of controller
for (int i = 0; i < 5; i++) {
        UIButton *but = [UIButton buttonWithType:UIButtonTypeCustom];
        [but setImage:[UIImage imageNamed:@"checkbox.png"] forState:UIControlStateNormal];
        [but setImage:[UIImage imageNamed:@"checkedbox.png"] forState:UIControlStateSelected];
        [but setFrame:CGRectMake(0, 0, 17, [...]

If you will need launch AppStore application with search request – use this example
NSString *str = @"itms-apps://ax.search.itunes.apple.com";
    str = [NSString stringWithFormat:@"%@/WebObjects/MZSearch.woa/wa/search?media=software&term=", str];
    str = [NSString stringWithFormat:@"%@3d4medical", str];
   
    [[UIApplication sharedApplication] openURL: [NSURL URLWithString:str]];

ToolbarSearch
This sample shows how to use a search field in a toolbar. When you start a search, a table view displaying recent searches matching the current search string is displayed in a popover.
New controller:
UIPopoverControllerDelegate

Create a navigation controller to contain the recent searches controller, and create the popover controller to contain the navigation controller.
UINavigationController *navigationController [...]

Change RGB color of the picture
- (UIImage *) changeColor: (UIImage *)image {
    UIGraphicsBeginImageContext(image.size);
   
    CGRect contextRect;
    contextRect.origin.x = 0.0f;
    contextRect.origin.y = 0.0f;
    contextRect.size = [image size];
    // Retrieve source image and begin image context
    CGSize itemImageSize = [image size];
    CGPoint itemImagePosition;
    itemImagePosition.x = ceilf((contextRect.size.width [...]

Here is a little tip on how to tell if a string contains another string, using the underused data type NSRange.
NSRange gives the starting location and the length of a given value, and is often used with arrays and strings. On this occasion we will use it to find the range of a substring within [...]

I created a class (Foo.m) which I would like to be able to call a method in the controller (MainViewController.m) which instantiated it. How do I do this?
One way you can do this is to create a property in your Foo class that references its creator. You should not retain this reference to avoid circular [...]