UIButton 例子

UICatalog這個例子
例子中得類方法:

+ (UIButton *)buttonWithTitle:    (NSString *)title
                                target:(id)target
                                selector:(SEL)selector
                                frame:(CGRect)frame
                                image:(UIImage *)image
                                imagePressed:(UIImage *)imagePressed
                                darkTextColor:(BOOL)darkTextColor
{    
    UIButton *button = [[UIButton alloc] initWithFrame:frame];
    // or you can do this:
    //        UIButton *button = [[UIButton buttonWithType:UIButtonTypeCustom] retain];
    //        button.frame = frame;
    
    button.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter;
    button.contentHorizontalAlignment = UIControlContentHorizontalAlignmentCenter;
    
    [button setTitle:title forState:UIControlStateNormal];    
    if (darkTextColor)
    {
        [button setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
    }
    else
    {
        [button setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
    }
    
    UIImage *newImage = [image stretchableImageWithLeftCapWidth:12.0 topCapHeight:0.0];
    [button setBackgroundImage:newImage forState:UIControlStateNormal];
    
    UIImage *newPressedImage = [imagePressed stretchableImageWithLeftCapWidth:12.0 topCapHeight:0.0];
    [button setBackgroundImage:newPressedImage forState:UIControlStateHighlighted];
    
    [button addTarget:target action:selector forControlEvents:UIControlEventTouchUpInside];
    
    // in case the parent view draws with a custom color or gradient, use a transparent color
    button.backgroundColor = [UIColor clearColor];
        
    return button;
}

用法:

- (void)createGrayButton
{    
    // create the UIButtons with various background images
    // white button:
    UIImage *buttonBackground = [UIImage imageNamed:@"whiteButton.png"];
    UIImage *buttonBackgroundPressed = [UIImage imageNamed:@"blueButton.png"];
    
    CGRect frame = CGRectMake(0.0, 0.0, kStdButtonWidth, kStdButtonHeight);
    
    grayButton = [ButtonsViewController buttonWithTitle:@"Gray"
                                target:self
                                selector:@selector(action:)
                                frame:frame
                                image:buttonBackground
                                imagePressed:buttonBackgroundPressed
                                darkTextColor:YES];
}