Difference between revisions of "UIImage"

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m (Undocumented C functions)
m (Undocumented C functions: The famous UIGetScreenImage().)
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Write the image data to photos album. This is similar to [http://developer.apple.com/iPhone/library/documentation/UIKit/Reference/UIKitFunctionReference/Reference/reference.html#//apple_ref/doc/uid/TP40006894-CH3-SW29 UIImageWriteToSavedPhotosAlbum] function in the SDK, except that you can choose the image format (the extension will always be *.jpg, however).
 
Write the image data to photos album. This is similar to [http://developer.apple.com/iPhone/library/documentation/UIKit/Reference/UIKitFunctionReference/Reference/reference.html#//apple_ref/doc/uid/TP40006894-CH3-SW29 UIImageWriteToSavedPhotosAlbum] function in the SDK, except that you can choose the image format (the extension will always be *.jpg, however).
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=== UIGetScreenImage ===
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{{function signature|signature=CGImageRef UIGetScreenImage();|firmware=2.0 –}}
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"Print screen" and returns the image. Note that this is a CGImage, so you need to convert it to a UIImage with {{ObjcCall|UIImage|imageWithCGImage:|ClassMethod=1}}.
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Note that, although being a "Get" function, the returned image actually has retain count of +1, and the caller (you) are responsible to CGImageRelease it.
  
 
== References ==
 
== References ==

Revision as of 20:40, 4 December 2009

UIImage is an Objective-C class that represents a bitmap image.

Undocumented methods

-_applicationIconImagePrecomposed: & -_smallApplicationIconImagePrecomposed:

From left to right: The original image; _applicationIconImagePrecomposed:NO; _applicationIconImagePrecomposed:YES; _smallApplicationIconImagePrecomposed:NO; _smallApplicationIconImagePrecomposed:YES
Signature -(UIImage*)_applicationIconImagePrecomposed:(BOOL)precomposed;
Available in 2.0 –
Signature -(UIImage*)_smallApplicationIconImagePrecomposed:(BOOL)precomposed;
Available in 2.0 –

These methods resize an image to icon size (59×59) or small icon size (29×29), clip out a rounded rectangle, draw shadows and apply a glossy overlay if required (when precomposed == NO), so that it resembles an icon.

If the input image is rectangular, the largest square portion in the top-left corner will be used.

_flatImageWithWhite:alpha:

Signature -(UIImage*)_flatImageWithWhite:(CGFloat)white alpha:(CGFloat)alpha;
Available in 2.0 –

Create an image having the same size as the original image, but filled with the solid color as the parameters.

_bezeledImageWithRed:green:blue:alpha:

Signature -(UIImage*) _bezeledImageWithRed:(CGFloat)red green:(CGFloat)green blue:(CGFloat)blue alpha:(CGFloat)alpha;
Available in 2.0 –

Create a solid white image having the same size as the original image, and then stroke the top 1px edge by the specified color.

_imageScaledToSize:interpolationQuality: & _imageScaledToProportion:interpolationQuality:

Signature -(UIImage*)_imageScaledToSize:(CGSize)newSize interpolationQuality:(CGInterpolationQuality)quality;
Available in 2.0 –
Signature -(UIImage*)_imageScaledToProportion:(CGFloat)scale interpolationQuality:(CGInterpolationQuality)quality;
Available in 2.0 –

Rescale the image to the new size.

+kitImageNamed:

Signature +(UIImage*)kitImageNamed:(NSString*)name;
Available in 2.0 –

Equivalent to _UIImageWithName(name).

+defaultDesktopImage

Signature +(UIImage*)defaultDesktopImage;
Available in 2.0 –

Return the user's lock screen image.

+setDesktopImageData:

Signature +(void)setDesktopImageData:(NSData*)jpegData;
Available in 2.0 –

Replace the user's lock screen image by the given JPEG data.

Undocumented C functions

_UIImageWithName

Signature UIImage* _UIImageWithName(NSString* name);
Available in 2.0 –

Obtain a built-in image. The name are stored in UIKit.framework/*.artwork. There are various ways to extract this information[1][2][3], and you can grab a (slightly outdated) list from http://test.saurik.com/winterboard/UIImages.txt.

UIImageDataWriteToSavedPhotosAlbum

Signature void UIImageDataWriteToSavedPhotosAlbum(NSData* imageData, id target, SEL selector, void* context);
Available in 3.1 –

Write the image data to photos album. This is similar to UIImageWriteToSavedPhotosAlbum function in the SDK, except that you can choose the image format (the extension will always be *.jpg, however).

UIGetScreenImage

Signature CGImageRef UIGetScreenImage();
Available in 2.0 –

"Print screen" and returns the image. Note that this is a CGImage, so you need to convert it to a UIImage with +[UIImage imageWithCGImage:].

Note that, although being a "Get" function, the returned image actually has retain count of +1, and the caller (you) are responsible to CGImageRelease it.

References