Difference between revisions of "UIImage"

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(-[UIImage _imageScaledToSize:interpolationQuality:] was removed in 4.0)
(Update info to 4.3.)
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== Undocumented methods ==
 
== Undocumented methods ==
=== -_applicationIconImagePrecomposed: & -_smallApplicationIconImagePrecomposed: ===
+
=== Precomposed icon ===
 
[[Image:AppIcon.png|right|framed|From left to right: The original image; <tt>_applicationIconImagePrecomposed:NO</tt>; <tt>_applicationIconImagePrecomposed:YES</tt>; <tt>_smallApplicationIconImagePrecomposed:NO</tt>; <tt>_smallApplicationIconImagePrecomposed:YES</tt>]]
 
[[Image:AppIcon.png|right|framed|From left to right: The original image; <tt>_applicationIconImagePrecomposed:NO</tt>; <tt>_applicationIconImagePrecomposed:YES</tt>; <tt>_smallApplicationIconImagePrecomposed:NO</tt>; <tt>_smallApplicationIconImagePrecomposed:YES</tt>]]
  
{{Function signature|signature=-(UIImage*)_applicationIconImagePrecomposed:(BOOL)precomposed;|firmware=2.0 –}}
+
{{Function signature|signature=-(UIImage*)_applicationIconImageForFormat:(int)format precomposed:(BOOL)precomposed scale:(CGFloat)scale;|firmware=4.0 –}}
 +
{{Function signature|signature=-(UIImage*)_applicationIconImageForFormat:(int)format precomposed:(BOOL)precomposed;|firmware=3.2 –}}
 +
{{Function signature|signature=-(UIImage*)_applicationIconImagePrecomposed:(BOOL)precomposed;|firmware=2.0 – 4.0}}
 
{{Function signature|signature=-(UIImage*)_smallApplicationIconImagePrecomposed:(BOOL)precomposed;|firmware=2.0 – 3.1}}
 
{{Function signature|signature=-(UIImage*)_smallApplicationIconImagePrecomposed:(BOOL)precomposed;|firmware=2.0 – 3.1}}
  
These methods resize an image to icon size (59&times;59) or small icon size (29&times;29), clip out a rounded rectangle, draw shadows and apply a glossy overlay if required (when <tt>precomposed == NO</tt>), so that it resembles an icon.
+
These methods resize an image to icon size, clip out a rounded rectangle, draw shadows and apply a glossy overlay if required (when <tt>precomposed == NO</tt>), so that it resembles an icon.
 +
 
 +
{| class="wikitable"
 +
|-
 +
! rowspan="2" | Format
 +
! colspan="2" | Size
 +
! colspan="3" | MobileIcons variant
 +
! rowspan="2" | Description
 +
|-
 +
! iPhone !! iPad
 +
! iPhone !! iPad 2x !! iPad 1x
 +
|-
 +
| 0 || 29&times;29 || 29&times;29 || 4 || 17 || 4 ||
 +
|-
 +
| 1 || 29&times;29 || 50&times;50 || 2 || 16 || 3 || the small icon that appears in Spotlight
 +
|-
 +
| 2 || 59&times;62 || 74&times;78 || 0 || 15 || 1 || the large icon that appears in home screen (default)
 +
|-
 +
| 3 || 44&times;45 || 74&times;78 || 22 || 23 || 1 || for use in GameCenter (?)
 +
|-
 +
| 4 || 59&times;62 || 74&times;78 || 24 || 25 || 26 || in gray scale
 +
|-
 +
| 5 || 31&times;37 || 64&times;64 || 18 || 19 || 5 || document-like picture filled with the specified image
 +
|-
 +
| 6 || 31&times;37 || 64&times;64 || 20 || 21 || 7 || document-like picture with a small icon
 +
|}
 +
 
 +
The rendering of icon is actually done by {{fwlink|MobileIcons}}.
  
 
If the input image is rectangular, the largest square portion in the top-left corner will be used.
 
If the input image is rectangular, the largest square portion in the top-left corner will be used.
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...
 
...
 
UIImage *regularIcon = [UIImage imageNamed:@"regularIcon.png"];
 
UIImage *regularIcon = [UIImage imageNamed:@"regularIcon.png"];
UIImage *renderedIcon = [regularIcon _applicationIconImagePrecomposed:NO];
+
UIImage *renderedIcon = [regularIcon _applicationIconImageForFormat:2 precomposed:NO];
 
NSData  *pngData = UIImagePNGRepresentation( renderedIcon );
 
NSData  *pngData = UIImagePNGRepresentation( renderedIcon );
 
[pngData writeToFile:@"/tmp/roundedIcon.png" atomically:YES];
 
[pngData writeToFile:@"/tmp/roundedIcon.png" atomically:YES];
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=== _bezeledImageWithRed:green:blue:alpha: ===
 
=== _bezeledImageWithRed:green:blue:alpha: ===
{{Function signature|signature=-(UIImage*) _bezeledImageWithRed:(CGFloat)red green:(CGFloat)green blue:(CGFloat)blue alpha:(CGFloat)alpha;|firmware=2.0 –}}
+
{{Function signature|signature=-(UIImage*) _bezeledImageWithRed:(CGFloat)red green:(CGFloat)green blue:(CGFloat)blue alpha:(CGFloat)alpha;|firmware=2.0 – 3.1}}
  
 
Create a solid white image having the same size as the original image, and then stroke the top 1px edge by the specified color.
 
Create a solid white image having the same size as the original image, and then stroke the top 1px edge by the specified color.
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=== +defaultDesktopImage ===
 
=== +defaultDesktopImage ===
{{Function signature|signature=+(UIImage*)defaultDesktopImage;|firmware=2.0 –}}
+
{{Function signature|signature=+(UIImage*)defaultDesktopImage;|firmware=2.0 – 4.1}}
  
 
Return the user's lock screen image.
 
Return the user's lock screen image.
  
 
=== +setDesktopImageData: ===
 
=== +setDesktopImageData: ===
{{Function signature|signature=+(void)setDesktopImageData:(NSData*)jpegData;|firmware=2.0 –}}
+
{{Function signature|signature=+(void)setDesktopImageData:(NSData*)jpegData;|firmware=2.0 – 3.2}}
 +
{{Function signature|signature=+(void)setDesktopImageData:(NSData*)data composedPortraitImageData:(NSData*)data2 composedLandscapeImageData:(NSData*)data3 forVariant:(int)variant;|firmware=4.0 – 4.1}}
  
 
Replace the user's lock screen image by the given JPEG data.
 
Replace the user's lock screen image by the given JPEG data.
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{{Function signature|signature=UIImage* _UIImageWithName(NSString* name);|firmware=2.0 –}}
 
{{Function signature|signature=UIImage* _UIImageWithName(NSString* name);|firmware=2.0 –}}
  
Obtain a built-in image. The name are stored in <tt>UIKit.framework/*.artwork</tt>. There are various ways to extract this information<ref>iPhoneShop http://code.google.com/p/iphoneshop/ – may not work on 3.x</ref><ref>http://svn.saurik.com/repos/menes/trunk/winterboard/UIImages.mm</ref><ref>http://code.google.com/p/networkpx/source/browse/etc/dump-artwork.m – Tested only on 3.x</ref>, and you can grab a (slightly outdated) list from http://test.saurik.com/winterboard/UIImages.txt.
+
Obtain a built-in image. The name are stored in <tt>UIKit.framework/*.artwork</tt>. There are various ways to extract this information<ref>iPhoneShop http://code.google.com/p/iphoneshop/ – may not work on 3.x</ref><ref>https://github.com/davepeck/iphone-tidbits</ref>, and you can grab a (slightly outdated) list from http://test.saurik.com/winterboard/UIImages.txt.
  
 
=== UIImageDataWriteToSavedPhotosAlbum ===
 
=== UIImageDataWriteToSavedPhotosAlbum ===
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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.
 
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.
  
Starting from 2009 Dec 14th, this function can be used for SDK apps<ref>http://www.steveperks.co.uk/post/Apple-Allows-UIGetScreenImage-For-iPhone.aspx</ref>.
+
This function can be used for SDK apps between 2009 December<ref>http://www.steveperks.co.uk/post/Apple-Allows-UIGetScreenImage-For-iPhone.aspx</ref> and 2010 July<ref>http://www.tuaw.com/2010/07/21/devsugar-rip-uigetscreenimage/</ref>
  
 
In firmware 3.2, <tt>UIGetScreenImage</tt> becomes an alias of the more appropriately-named <tt>UICreateScreenImage</tt>.
 
In firmware 3.2, <tt>UIGetScreenImage</tt> becomes an alias of the more appropriately-named <tt>UICreateScreenImage</tt>.

Revision as of 22:13, 8 April 2011

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

Undocumented methods

Precomposed icon

From left to right: The original image; _applicationIconImagePrecomposed:NO; _applicationIconImagePrecomposed:YES; _smallApplicationIconImagePrecomposed:NO; _smallApplicationIconImagePrecomposed:YES
Signature -(UIImage*)_applicationIconImageForFormat:(int)format precomposed:(BOOL)precomposed scale:(CGFloat)scale;
Available in 4.0 –
Signature -(UIImage*)_applicationIconImageForFormat:(int)format precomposed:(BOOL)precomposed;
Available in 3.2 –
Signature -(UIImage*)_applicationIconImagePrecomposed:(BOOL)precomposed;
Available in 2.0 – 4.0
Signature -(UIImage*)_smallApplicationIconImagePrecomposed:(BOOL)precomposed;
Available in 2.0 – 3.1

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

Format Size MobileIcons variant Description
iPhone iPad iPhone iPad 2x iPad 1x
0 29×29 29×29 4 17 4
1 29×29 50×50 2 16 3 the small icon that appears in Spotlight
2 59×62 74×78 0 15 1 the large icon that appears in home screen (default)
3 44×45 74×78 22 23 1 for use in GameCenter (?)
4 59×62 74×78 24 25 26 in gray scale
5 31×37 64×64 18 19 5 document-like picture filled with the specified image
6 31×37 64×64 20 21 7 document-like picture with a small icon

The rendering of icon is actually done by MobileIcons.

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

Example:

@interface UIImage (privateAPI)
-(UIImage*)_applicationIconImagePrecomposed:(BOOL)precomposed;
@end
...
UIImage *regularIcon = [UIImage imageNamed:@"regularIcon.png"];
UIImage *renderedIcon = [regularIcon _applicationIconImageForFormat:2 precomposed:NO];
NSData  *pngData = UIImagePNGRepresentation( renderedIcon );
[pngData writeToFile:@"/tmp/roundedIcon.png" atomically:YES];

_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 – 3.1

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 – 3.2
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 – 4.1

Return the user's lock screen image.

+setDesktopImageData:

Signature +(void)setDesktopImageData:(NSData*)jpegData;
Available in 2.0 – 3.2
Signature +(void)setDesktopImageData:(NSData*)data composedPortraitImageData:(NSData*)data2 composedLandscapeImageData:(NSData*)data3 forVariant:(int)variant;
Available in 4.0 – 4.1

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], 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 –
Signature CGImageRef UICreateScreenImage();
Available in 3.2 –

"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.

This function can be used for SDK apps between 2009 December[3] and 2010 July[4]

In firmware 3.2, UIGetScreenImage becomes an alias of the more appropriately-named UICreateScreenImage.

References