NSView

Authors

Scott Christley(scottc@net-community.com)
Felipe A. Rodriguez(far@ix.netcom.com)
Ovidiu Predescu(ovidiu@net-community.com)
Richard Frith-Macdonald(richard@brainstorm.co.uk)

The view class which encapsulates all drawing functionality

Contents -

NSView
Software documentation for the NSView(PrivateMethods) category

NSView

NSView is an abstract class which provides facilities for drawing in a window and receiving events. It is the superclass of many of the visual elements of the GUI.

In order to display itself, a view must be placed in a window (represented by an NSWindow object). Within the window is a hierarchy of NSViews, headed by the window's content view. Every other view in a window is a descendant of this view.

Subclasses can override drawRect: in order to implement their appearance. Other methods of NSView and NSResponder can also be overridden to handle user generated events.

NSView : NSResponder

Declared in:

AppKit/NSView.h

Standards:

MacOS-X

OpenStep

GNUstep

Method summary

defaultMenu

+ (NSMenu*) defaultMenu;

Description forthcoming.

focusView

+ (NSView*) focusView;

Return the view at the top of graphics contexts stack or nil if none is focused.

acceptsFirstMouse:

- (BOOL) acceptsFirstMouse: (NSEvent*)theEvent;

Returns YES if the view object will accept the first click received when in an inactive window, and NO otherwise.

addCursorRect:cursor:

- (void) addCursorRect: (NSRect)aRect cursor: (NSCursor*)anObject;

Description forthcoming.

addSubview:

- (void) addSubview: (NSView*)aView;

Adds aView as a subview of the receiver.

addSubview:positioned:relativeTo:

- (void) addSubview: (NSView*)aView positioned: (NSWindowOrderingMode)place relativeTo: (NSView*)otherView;

Description forthcoming.

addToPageSetup

- (void) addToPageSetup;

Description forthcoming.

addToolTipRect:owner:userData:

- (NSToolTipTag) addToolTipRect: (NSRect)aRect owner: (id)anObject userData: (void*)data;

Description forthcoming.

addTrackingRect:owner:userData:assumeInside:

- (NSTrackingRectTag) addTrackingRect: (NSRect)aRect owner: (id)anObject userData: (void*)data assumeInside: (BOOL)flag;

Description forthcoming.

adjustPageHeightNew:top:bottom:limit:

- (void) adjustPageHeightNew: (float*)newBottom top: (float)oldTop bottom: (float)oldBottom limit: (float)bottomLimit;

Description forthcoming.

adjustPageWidthNew:left:right:limit:

- (void) adjustPageWidthNew: (float*)newRight left: (float)oldLeft right: (float)oldRight limit: (float)rightLimit;

Description forthcoming.

adjustScroll:

- (NSRect) adjustScroll: (NSRect)newVisible;

Description forthcoming.

allocateGState

- (void) allocateGState;

Tell the view to maintain a private gstate object which encapsulates all the information about drawing, such as coordinate transforms, line widths, etc. If you do not invoke this method, a gstate object is constructed each time the view is lockFocused. Allocating a private gstate may improve the performance of views that are focused a lot and have a lot of customized drawing parameters.

View subclasses should override the setUpGstate method to set these custom parameters.

ancestorSharedWithView:

- (NSView*) ancestorSharedWithView: (NSView*)aView;

Returns self if aView is the receiver or aView is a subview of the receiver, the ancestor view shared by aView and the receiver, if any, aView if it is an ancestor of the receiver, otherwise returns nil.

autoresizesSubviews

- (BOOL) autoresizesSubviews;

Description forthcoming.

autoresizingMask

- (unsigned int) autoresizingMask;

Description forthcoming.

autoscroll:

- (BOOL) autoscroll: (NSEvent*)theEvent;

Description forthcoming.

beginDocument

- (void) beginDocument;

Writes header and job information for the PostScript document. This includes at a minimum, PostScript header information. It may also include job setup information if the output is intended for a printer (i.e. not an EPS file). Most of the information for writing the header comes from the NSPrintOperation and NSPrintInfo objects associated with the current print operation. There isn't normally anything that the program needs to override at the beginning of a document, although if there is additional setup that needs to be done, you can override the NSView's methods endHeaderComments, endPrologue, beginSetup, and/or endSetup. This method calls the above methods in the listed order before or after writing the required information. For an EPS operation, the beginSetup and endSetup methods aren't used.

beginPage:label:bBox:fonts:

- (void) beginPage: (int)ordinalNum label: (NSString*)aString bBox: (NSRect)pageRect fonts: (NSString*)fontNames;

Description forthcoming.

beginPageInRect:atPlacement:

- (void) beginPageInRect: (NSRect)aRect atPlacement: (NSPoint)location;

Description forthcoming.

beginPageSetupRect:placement:

- (void) beginPageSetupRect: (NSRect)aRect placement: (NSPoint)location;

Description forthcoming.

beginPrologueBBox:creationDate:createdBy:fonts:forWhom:pages:title:

- (void) beginPrologueBBox: (NSRect)bBox creationDate: (NSString*)dateCreated createdBy: (NSString*)anApplication fonts: (NSString*)fontNames forWhom: (NSString*)user pages: (int)numPages title: (NSString*)aTitle;

Description forthcoming.

beginSetup

- (void) beginSetup;

Description forthcoming.

beginTrailer

- (void) beginTrailer;

Description forthcoming.

bounds

- (NSRect) bounds;

Description forthcoming.

boundsRotation

- (float) boundsRotation;

Description forthcoming.

canDraw

- (BOOL) canDraw;

Description forthcoming.

centerScanRect:

- (NSRect) centerScanRect: (NSRect)aRect;

Description forthcoming.

convertPoint:fromView:

- (NSPoint) convertPoint: (NSPoint)aPoint fromView: (NSView*)aView;

Description forthcoming.

convertPoint:toView:

- (NSPoint) convertPoint: (NSPoint)aPoint toView: (NSView*)aView;

Description forthcoming.

convertRect:fromView:

- (NSRect) convertRect: (NSRect)aRect fromView: (NSView*)aView;

Description forthcoming.

convertRect:toView:

- (NSRect) convertRect: (NSRect)aRect toView: (NSView*)aView;

Description forthcoming.

convertSize:fromView:

- (NSSize) convertSize: (NSSize)aSize fromView: (NSView*)aView;

Description forthcoming.

convertSize:toView:

- (NSSize) convertSize: (NSSize)aSize toView: (NSView*)aView;

Description forthcoming.

dataWithEPSInsideRect:

- (NSData*) dataWithEPSInsideRect: (NSRect)aRect;

Description forthcoming.

dataWithPDFInsideRect:

- (NSData*) dataWithPDFInsideRect: (NSRect)aRect;

Description forthcoming.

didAddSubview:

- (void) didAddSubview: (NSView*)subview;

Description forthcoming.

discardCursorRects

- (void) discardCursorRects;

Description forthcoming.

display

- (void) display;

Description forthcoming.

displayIfNeeded

- (void) displayIfNeeded;

Description forthcoming.

displayIfNeededIgnoringOpacity

- (void) displayIfNeededIgnoringOpacity;

Description forthcoming.

displayIfNeededInRect:

- (void) displayIfNeededInRect: (NSRect)aRect;

Description forthcoming.

displayIfNeededInRectIgnoringOpacity:

- (void) displayIfNeededInRectIgnoringOpacity: (NSRect)aRect;

Description forthcoming.

displayRect:

- (void) displayRect: (NSRect)rect;

Description forthcoming.

displayRectIgnoringOpacity:

- (void) displayRectIgnoringOpacity: (NSRect)aRect;

Description forthcoming.

dragFile:fromRect:slideBack:event:

- (BOOL) dragFile: (NSString*)filename fromRect: (NSRect)rect slideBack: (BOOL)slideFlag event: (NSEvent*)event;

Description forthcoming.

dragImage:at:offset:event:pasteboard:source:slideBack:

- (void) dragImage: (NSImage*)anImage at: (NSPoint)viewLocation offset: (NSSize)initialOffset event: (NSEvent*)event pasteboard: (NSPasteboard*)pboard source: (id)sourceObject slideBack: (BOOL)slideFlag;

Description forthcoming.

drawPageBorderWithSize:

- (void) drawPageBorderWithSize: (NSSize)borderSize;

Description forthcoming.

drawRect:

- (void) drawRect: (NSRect)rect;

This method is invoked to handle drawing inside the view. The default NSView's implementation does nothing; subclasses might override it to draw something inside the view. Since NSView's implementation is guaranteed to be empty, you should not call super's implementation when you override it in subclasses. drawRect: is invoked when the focus has already been locked on the view; you can use arbitrary postscript functions in drawRect: to draw inside your view; the coordinate system in which you draw is the view's own coordinate system (this means for example that you should refer to the rectangle covered by the view using its bounds, and not its frame). The argument of drawRect: is the rectangle which needs to be redrawn. In a lossy implementation, you can ignore the argument and redraw the whole view; if you are aiming at performance, you may want to redraw only what is inside the rectangle which needs to be redrawn; this usually improves drawing performance considerably.

drawSheetBorderWithSize:

- (void) drawSheetBorderWithSize: (NSSize)borderSize;

Description forthcoming.

enclosingScrollView

- (NSScrollView*) enclosingScrollView;

Description forthcoming.

endDocument

- (void) endDocument;

Description forthcoming.

endHeaderComments

- (void) endHeaderComments;

Description forthcoming.

endPage

- (void) endPage;

Description forthcoming.

endPageSetup

- (void) endPageSetup;

Description forthcoming.

endPrologue

- (void) endPrologue;

Description forthcoming.

endSetup

- (void) endSetup;

Description forthcoming.

endTrailer

- (void) endTrailer;

Description forthcoming.

fax:

- (void) fax: (id)sender;

Description forthcoming.

frame

- (NSRect) frame;

Description forthcoming.

frameRotation

- (float) frameRotation;

Description forthcoming.

gState

- (int) gState;

Returns an identifier that represents the view's gstate object, which is used to encapsulate drawing information about the view. Most of the time a gstate object is created from scratch when the view is focused, so if the view is not currently focused or allocateGState has not been called, then this method will

heightAdjustLimit

- (float) heightAdjustLimit;

Description forthcoming.

hitTest:

- (NSView*) hitTest: (NSPoint)aPoint;

Returns the subview, lowest in the receiver's hierarchy, which contains aPoint

initWithFrame:

- (id) initWithFrame: (NSRect)frameRect;

Description forthcoming.

isDescendantOf:

- (BOOL) isDescendantOf: (NSView*)aView;

Returns YES if aView is an ancestor of the receiver.

isFlipped

- (BOOL) isFlipped;

Description forthcoming.

isOpaque

- (BOOL) isOpaque;

Description forthcoming.

isRotatedFromBase

- (BOOL) isRotatedFromBase;

Description forthcoming.

isRotatedOrScaledFromBase

- (BOOL) isRotatedOrScaledFromBase;

Description forthcoming.

knowsPageRange:

- (BOOL) knowsPageRange: (NSRange*)range;

Description forthcoming.

knowsPagesFirst:last:

- (BOOL) knowsPagesFirst: (int*)firstPageNum last: (int*)lastPageNum;

Description forthcoming.

locationOfPrintRect:

- (NSPoint) locationOfPrintRect: (NSRect)aRect;

Description forthcoming.

lockFocus

- (void) lockFocus;

Description forthcoming.

lockFocusIfCanDraw

- (BOOL) lockFocusIfCanDraw;

Description forthcoming.

menuForEvent:

- (NSMenu*) menuForEvent: (NSEvent*)theEvent;

Description forthcoming.

mouse:inRect:

- (BOOL) mouse: (NSPoint)aPoint inRect: (NSRect)aRect;

Returns whether or not aPoint lies within aRect

needsDisplay

- (BOOL) needsDisplay;

Description forthcoming.

nextKeyView

- (NSView*) nextKeyView;

Description forthcoming.

nextValidKeyView

- (NSView*) nextValidKeyView;

Description forthcoming.

opaqueAncestor

- (NSView*) opaqueAncestor;

Description forthcoming.

performKeyEquivalent:

- (BOOL) performKeyEquivalent: (NSEvent*)theEvent;

Description forthcoming.

performMnemonic:

- (BOOL) performMnemonic: (NSString*)aString;

Description forthcoming.

postsBoundsChangedNotifications

- (BOOL) postsBoundsChangedNotifications;

Description forthcoming.

postsFrameChangedNotifications

- (BOOL) postsFrameChangedNotifications;

Description forthcoming.

previousKeyView

- (NSView*) previousKeyView;

Description forthcoming.

previousValidKeyView

- (NSView*) previousValidKeyView;

Description forthcoming.

print:

- (void) print: (id)sender;

Description forthcoming.

printJobTitle

- (NSString*) printJobTitle;

Description forthcoming.

rectForPage:

- (NSRect) rectForPage: (int)page;

Description forthcoming.

reflectScrolledClipView:

- (void) reflectScrolledClipView: (NSClipView*)aClipView;

Description forthcoming.

registerForDraggedTypes:

- (void) registerForDraggedTypes: (NSArray*)types;

Description forthcoming.

releaseGState

- (void) releaseGState;

Frees the gstate object, if there is one. Note that the next time the view is lockFocused, the gstate will be allocated again.

removeAllToolTips

- (void) removeAllToolTips;

Description forthcoming.

removeCursorRect:cursor:

- (void) removeCursorRect: (NSRect)aRect cursor: (NSCursor*)anObject;

Description forthcoming.

removeFromSuperview

- (void) removeFromSuperview;

Removes the receiver from its superviews list of subviews, by invoking the superviews [ -removeSubview: ] method, and marks the rectangle that the reciever occupied in the superview as needing redisplay.

This is dangerous to use during display, since it alters the rectangles needing display. In this case, you can use the -removeFromSuperviewWithoutNeedingDisplay method instead.

removeFromSuperviewWithoutNeedingDisplay

- (void) removeFromSuperviewWithoutNeedingDisplay;

Removes the receiver from its superviews list of subviews, by invoking the superviews [ -removeSubview: ] method.

removeSubview:

- (void) removeSubview: (NSView*)aSubview;

Removes aSubview from the receivers list of subviews and from the responder chain.

Also invokes [aView -viewWillMoveToWindow: nil] to handle removal of aView (and recursively, its children) from its window - performing tidyup by invalidating cursor rects etc.

Software documentation for the NSView(PrivateMethods) category

NSView(PrivateMethods)

Declared in:

AppKit/NSView.h

Standards:

NotOpenStep

NotMacOS-X

GNUstep

Description forthcoming.

Method summary