iOS开发中用到的控件（一）

控件一：圆形图片

@interface UIImage (CircleImage)

-(UIImage *) circleImageWithParam:(CGFloat) inset;

@end

@implementation UIImage (CircleImage)

-(UIImage *) circleImageWithParam:(CGFloat) inset {

    UIGraphicsBeginImageContext(CGSizeMake(104,
104));

    CGContextRef context =
UIGraphicsGetCurrentContext();

    CGContextSetLineWidth(context,
2);

    CGContextSetStrokeColorWithColor(context, [UIColor
orangeColor].CGColor);

    CGRect rect = CGRectMake(inset, inset,
94, 94);

    CGContextAddEllipseInRect(context, rect);
    CGContextClip(context);

    [self drawInRect:rect];

//    CGContextAddEllipseInRect(context, rect);

//    CGContextStrokePath(context);

    UIImage *newimg =
UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    return newimg;

}

@end

控件二：导航条返回按钮

@interface UIBarButtonItem (CustomBackItem)
+ (UIBarButtonItem *)backArrowButtonWithTarget:(id)target action:(SEL)action;
@end

@implementation UIBarButtonItem (CustomBackItem)
+ (UIBarButtonItem *)backArrowButtonWithTarget:(id)target action:(SEL)action
{
    UIImage *buttonImage = [UIImage
imageNamed:@"go_back.png"];
    
    //create the button and assign the image
    UIButton *button = [UIButton
buttonWithType:UIButtonTypeCustom];
    [button setImage:buttonImage
forState:UIControlStateNormal];
    
    //set the frame of the button to the size of the image (see note below)
    button.frame = CGRectMake(0,
0, buttonImage.size.width, buttonImage.size.height);
    
    [button addTarget:target
action:action forControlEvents:UIControlEventTouchUpInside];
    
    //create a UIBarButtonItem with the button as a custom view
    UIBarButtonItem *customBarItem = [[UIBarButtonItem
alloc] initWithCustomView:button];
    return [customBarItem
autorelease];
}