Difference between revisions of "Cocoa Internals/Extensions"
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|- | |- | ||
|lclClientFrame | |lclClientFrame | ||
− | |Returns client rectangle (content of the control) in the control's coordinate system | + | |Returns client rectangle (content of the control) in the control's coordinate system |
|does nothing | |does nothing | ||
| | | | ||
+ | |- | ||
+ | |lclFrame | ||
+ | |Returns controls position rectangle in the parent's coordinate system | ||
+ | |does nothing | ||
+ | |frame() | ||
|} | |} | ||
Revision as of 19:50, 23 December 2017
Extensions are used to add additional lcl-friendly methods to all Cocoa classes. The default implementation of each method should:
- either indicate that a class is not a LCL-specific class (it's Cocoa native) thus should be handled with care
- provide a basic functionality for LCL types (for example setting a control bounds using TRect type. Where cocoa is using float-point NSRect)
Extensions
LCLObjectExtension
The extensions adds additional methods to NSObject class of cocoa. (This is TObject counterpart, where (almost) all classes in Cocoa inherit from).
A lot of the methods below are control specific methods, thus it might be a good idea to elevate the extension from NSObject to NSView or NSControl. However, this might impact other control-like objects (i.w. NSWindow?)
LCLObjectExtensions methods are:
Method | Description | Default behavior | |
---|---|---|---|
LCLObjectExtension | LCLViewExtensions | ||
lclIsEnabled | Returns true/false if control is enabled | false | |
lclSetEnable | Enables or disables the control | does nothing | |
lclisVisible | Returns true/false if control is visible | false | not hidden() |
lclSetVisible | shows or hides a control | does nothing | setHidden() (where is the method in the documentation? deprecated?) |
lclisHandle | Returns true if the instance of the class can be considered a LCL handle | false | |
lclClientFrame | Returns client rectangle (content of the control) in the control's coordinate system | does nothing | |
lclFrame | Returns controls position rectangle in the parent's coordinate system | does nothing | frame() |
Convention
- All lcl extension methods should start with "lcl" to distinguish them Cocoa native methods.