iOS UIimage的拉伸的三种方法

 // - (UIImage *)stretchableImageWithLeftCapWidth:(NSInteger)leftCapWidth topCapHeight:(NSInteger)topCapHeight __TVOS_PROHIBITED;

    //leftCapWidth:左边不拉伸区域

    //topCapHeight:上面不拉伸区域

  UIImage *image =[UIImageimageNamed:@"chatdetail_info_other"];

    UIImageView *imageView=[[UIImageViewalloc]initWithFrame:CGRectMake(20,60, image.size.width, image.size.height)];

    imageView.image=image;

    [self.viewaddSubview:imageView];

    UIImage *image1 =[UIImageimageNamed:@"chatdetail_info_other"];

    image1=[image1 stretchableImageWithLeftCapWidth:image1.size.width*0.3topCapHeight:image1.size.height*0.7];

    UIImageView *imageView1=[[UIImageViewalloc]initWithFrame:CGRectMake(20,220, 200,150)];

    imageView1.image=image1;

    [self.viewaddSubview:imageView1];

  //- (UIImage *)resizableImageWithCapInsets:(UIEdgeInsets)capInsets resizingMode:(UIImageResizingMode)resizingMode NS_AVAILABLE_IOS(6_0);

    //    对比iOS5.0中的方法，只多了一个UIImageResizingMode参数，用来指定拉伸的模式：

    //    UIImageResizingModeStretch：拉伸模式，通过拉伸UIEdgeInsets指定的矩形区域来填充图片

    //    UIImageResizingModeTile：平铺模式，通过重复显示UIEdgeInsets指定的矩形区域来填充图片

    [image1 resizableImageWithCapInsets:UIEdgeInsetsMake(image1.size.height*0.9, image1.size.width*0.9, image1.size.height*0.9, image1.size.width*0.9)resizingMode:UIImageResizingModeStretch];