如何缩放选定的图像iPhone SDK？

Question

假设我从图像选择器中选择了图像，现在我想缩放该图像并想要在按钮或任何图像视图中设置缩放的图像。

Answer 1

，当你选择从选择器中的图像，它应该returt UIImage类型。只是将它设置为图像的任何UIView的sublass（按钮是UIView的子类也是如此）：

[yourUIImageView setImage:UIImageFronUIPicker]; 
[yourUIButton setBackgroundImage:UIImageFronUIPicker]; 

等等...

Answer 2

你看看UIImageView的contentMode财产。

typedef enum { 
    UIViewContentModeScaleToFill, 
    UIViewContentModeScaleAspectFit, 
    UIViewContentModeScaleAspectFill, 
    UIViewContentModeRedraw, 
    UIViewContentModeCenter, 
    UIViewContentModeTop, 
    UIViewContentModeBottom, 
    UIViewContentModeLeft, 
    UIViewContentModeRight, 
    UIViewContentModeTopLeft, 
    UIViewContentModeTopRight, 
    UIViewContentModeBottomLeft, 
    UIViewContentModeBottomRight, 
} UIViewContentMode; 

Answer 3

实现您的视图控制器UIImagePickerControllerDelegate并实施以下

委托方法

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)image editingInfo:(NSDictionary *)editingInfo { 

    [selectedImageBtn setImage:image forState:UIControlStateNormal]; 
    [[imagePicker parentViewController] dismissModalViewControllerAnimated:YES]; 

} 
- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker { 
    [[imagePicker parentViewController] dismissModalViewControllerAnimated:YES]; 
}