图片阴影效果的实现

UIImageView*pageContenterImageView = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"onePageApple.png"]];

//添加边框

CALayer*layer = [pageContenterImageViewlayer];

layer.borderColor= [[UIColor whiteColor]CGColor];

layer.borderWidth=0.0f;

//添加四个边阴影

pageContenterImageView.layer.shadowColor= [UIColor blackColor].CGColor;

pageContenterImageView.layer.shadowOffset=CGSizeMake(0,0);

pageContenterImageView.layer.shadowOpacity=0.5;

pageContenterImageView.layer.shadowRadius=5.0;

//添加两个边阴影

//pageContenterImageView.layer.shadowColor = [UIColor blackColor].CGColor;

// pageContenterImageView.layer.shadowOffset = CGSizeMake(2, 2);

// pageContenterImageView.layer.shadowOpacity = 0.5;

// pageContenterImageView.layer.shadowRadius = 2.0;

//-------------

阴影渲染会严重消耗内存 ,导致程序咔叽.

/*阴影效果*/

//添加边框

CALayer*layer = [self.pageContenter layer];

layer.borderColor= [[UIColorwhiteColor]CGColor];

layer.borderWidth=0.0f;

//添加四个边阴影

self.pageContenter.layer.shadowColor= [UIColorblackColor].CGColor;//阴影颜色

self.pageContenter.layer.shadowOffset=CGSizeMake(0,0);//阴影偏移

self.pageContenter.layer.shadowOpacity=0.5;//阴影不透明度

self.pageContenter.layer.shadowRadius=5.0;//阴影半径

//添加两个边阴影

//self.pageContenter.layer.shadowColor = [UIColor blackColor].CGColor;

//self.pageContenter.layer.shadowOffset = CGSizeMake(2, 2);

//self.pageContenter.layer.shadowOpacity = 0.5;

//self.pageContenter.layer.shadowRadius = 2.0;