阴影效果片段代码

转http://blog.csdn.net/toddmi/article/details/8133967

给一个对象简单设置阴影效果：

Lable.shadowColor = color;
Lable.shadowOffset = CGSizeMake(0, -1.0);

或

UIView *testView = [[UIView alloc] initWithFrame:CGRectMake(30, 30, 130, 130)];
[testView setBackgroundColor:[UIColor grayColor]];
[[testView layer] setShadowOffset:CGSizeMake(15, 15)];  //设置阴影位置相对于Object位置的偏移值
[[testView layer] setShadowRadius:0];
[[testView layer] setShadowOpacity:0.6];
[[testView layer] setShadowColor:[UIColor grayColor].CGColor];
[self.view addSubview:testView];
[testView release];

根据path设置阴影效果：

#import <QuartzCore/QuartzCore.h>

@implementation UIView (NKShadow)


// add the shadow effect to the view
-(void)addShadow{

    self.layer.shadowOpacity = 0.4;
    self.layer.shadowRadius = 0.9;
    self.layer.shadowOffset = CGSizeMake(0, 0);

    UIBezierPath *path = [UIBezierPath bezierPath];

    CGPoint p1 = CGPointMake(self.frame.origin.x, self.frame.origin.y+self.frame.size.height);
    CGPoint p2 = CGPointMake(self.frame.origin.x+self.frame.size.width, p1.y);
    CGPoint c1 = CGPointMake((p1.x+p2.x)/4 , p1.y+6.0);
    CGPoint c2 = CGPointMake(c1.x*3, c1.y);

    [path moveToPoint:p1];
    [path addCurveToPoint:p2 controlPoint1:c1 controlPoint2:c2];

    self.layer.shadowPath = path.CGPath;
}

-(void)addGrayGradientShadow{
    // 0.8 is a good feeling shadowOpacity
    self.layer.shadowOpacity = 0.4;

    // The Width and the Height of the shadow rect
    CGFloat rectWidth = 10.0;
    CGFloat rectHeight = self.frame.size.height;

    // Creat the path of the shadow
    CGMutablePathRef shadowPath = CGPathCreateMutable();
    // Move to the (0, 0) point
    CGPathMoveToPoint(shadowPath, NULL, 0.0, 0.0);
    // Add the Left and right rect
    CGPathAddRect(shadowPath, NULL, CGRectMake(0.0-rectWidth, 0.0, rectWidth, rectHeight));
    CGPathAddRect(shadowPath, NULL, CGRectMake(self.frame.size.width, 0.0, rectWidth, rectHeight));

    self.layer.shadowPath = shadowPath;
    CGPathRelease(shadowPath);
    // Since the default color of the shadow is black, we do not need to set it now
    //self.layer.shadowColor = [UIColor blackColor].CGColor;

    self.layer.shadowOffset = CGSizeMake(0, 0);
    // This is very important, the shadowRadius decides the feel of the shadow
    self.layer.shadowRadius = 10.0;
}


@end

UIView以外的区域设置阴影效果：

[[UIColor colorWithWhite:0.0f alpha:0.5f] setFill];//阴影效果  根据透明度来设计
    UIRectFill( rect );
    CGRect holeRect = CGRectMake(holeX, holeY, holeWidth, holeHeight);//设置透明范围
    CGRect holeRectIntersection = CGRectIntersection( holeRect, rect );
    [[UIColor clearColor] setFill];
    UIRectFill( holeRectIntersection );

UIView设置边框：

//UIView设置边框
[[testView layer] setCornerRadius:5];
[[testView layer] setBorderWidth:2];
[[testView layer] setBorderColor:[UIColor redColor].CGColor];

拉伸一张图片：

UIImage *smallImage = [UIImage imageNamed:@"hc_03.png"];
UIImageView *imageView = [[UIImageView alloc] initWithImage:smallImage];
[imageView setFrame:CGRectMake(0, 20, 320, 44)];
imageView.contentMode = UIViewContentModeScaleToFill;
[self.view addSubview:imageView];

[imageView release];