/* |
File: DraggableItemView.m |
Abstract: Part of the DraggableItemView project referenced in the |
View Programming Guide for Cocoa documentation. |
|
Short Circuting the Event Loop Edition. |
Version: 1.1 |
|
Disclaimer: IMPORTANT: This Apple software is supplied to you by Apple |
Inc. ("Apple") in consideration of your agreement to the following |
terms, and your use, installation, modification or redistribution of |
this Apple software constitutes acceptance of these terms. If you do |
not agree with these terms, please do not use, install, modify or |
redistribute this Apple software. |
|
In consideration of your agreement to abide by the following terms, and |
subject to these terms, Apple grants you a personal, non-exclusive |
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"Apple Software"), to use, reproduce, modify and redistribute the Apple |
Software, with or without modifications, in source and/or binary forms; |
provided that if you redistribute the Apple Software in its entirety and |
without modifications, you must retain this notice and the following |
text and disclaimers in all such redistributions of the Apple Software. |
Neither the name, trademarks, service marks or logos of Apple Inc. may |
be used to endorse or promote products derived from the Apple Software |
without specific prior written permission from Apple. Except as |
expressly stated in this notice, no other rights or licenses, express or |
implied, are granted by Apple herein, including but not limited to any |
patent rights that may be infringed by your derivative works or by other |
works in which the Apple Software may be incorporated. |
|
The Apple Software is provided by Apple on an "AS IS" basis. APPLE |
MAKES NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION |
THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS |
FOR A PARTICULAR PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND |
OPERATION ALONE OR IN COMBINATION WITH YOUR PRODUCTS. |
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IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL |
OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
INTERRUPTION) ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION, |
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STRICT LIABILITY OR OTHERWISE, EVEN IF APPLE HAS BEEN ADVISED OF THE |
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Copyright (C) 2011 Apple Inc. All Rights Reserved. |
|
*/ |
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#import "DraggableItemView.h" |
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@implementation DraggableItemView |
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// ----------------------------------- |
// Initialize the View |
// ----------------------------------- |
|
- (id)initWithFrame:(NSRect)frame { |
self = [super initWithFrame:frame]; |
if (self) { |
// setup the starting location of the |
// draggable item |
[self setItemPropertiesToDefault:self]; |
} |
return self; |
} |
|
// ----------------------------------- |
// Release the View |
// ----------------------------------- |
|
- (void)dealloc |
{ |
// release the color items and set |
// the instance variables to nil |
[itemColor release]; |
itemColor=nil; |
|
[backgroundColor release]; |
backgroundColor=nil; |
|
// call super |
[super dealloc]; |
} |
|
// ----------------------------------- |
// Draw the View Content |
// ----------------------------------- |
|
- (void)drawRect:(NSRect)rect |
{ |
// erase the background by drawing white |
[[NSColor whiteColor] set]; |
[NSBezierPath fillRect:rect]; |
|
// set the current color for the draggable item |
[[self itemColor] set]; |
|
// draw the draggable item |
[NSBezierPath fillRect:[self calculatedItemBounds]]; |
} |
|
- (BOOL)isOpaque |
{ |
// If the background color is opaque, return YES |
// otherwise, return NO |
return [[self backgroundColor] alphaComponent] >= 1.0 ? YES : NO; |
} |
|
|
// ----------------------------------- |
// Modify the item location |
// ----------------------------------- |
|
- (void)offsetLocationByX:(float)x andY:(float)y |
{ |
// tell the display to redraw the old rect |
[self setNeedsDisplayInRect:[self calculatedItemBounds]]; |
|
// since the offset can be generated by both mouse moves |
// and moveUp:, moveDown:, etc.. actions, we'll invert |
// the deltaY amount based on if the view is flipped or |
// not. |
int invertDeltaY = [self isFlipped] ? -1: 1; |
|
location.x=location.x+x; |
location.y=location.y+y*invertDeltaY; |
|
// invalidate the new rect location so that it'll |
// be redrawn |
[self setNeedsDisplayInRect:[self calculatedItemBounds]]; |
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} |
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// ----------------------------------- |
// Hit test the item |
// ----------------------------------- |
|
- (BOOL)isPointInItem:(NSPoint)testPoint |
{ |
BOOL itemHit=NO; |
|
// test first if we're in the rough bounds |
itemHit = NSPointInRect(testPoint,[self calculatedItemBounds]); |
|
// yes, lets further refine the testing |
if (itemHit) { |
|
} |
|
return itemHit; |
} |
|
// ----------------------------------- |
// Handle Mouse Events |
// ----------------------------------- |
|
// ----------------------------------- |
// Short Circuited mouseDown: handler |
// ----------------------------------- |
|
|
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-(void)mouseDown:(NSEvent *)event |
{ |
BOOL loop = YES; |
|
NSPoint clickLocation; |
|
// convert the initial click location into the view coords |
clickLocation = [self convertPoint:[event locationInWindow] |
fromView:nil]; |
|
// did the click occur in the draggable item? |
if ([self isPointInItem:clickLocation]) { |
// we're dragging, so let's set the cursor |
// to the closed hand |
[[NSCursor closedHandCursor] push]; |
|
NSPoint newDragLocation; |
|
// the tight event loop pattern doesn't require the use |
// of any instance variables, so we'll use a local |
// variable localLastDragLocation instead. |
NSPoint localLastDragLocation; |
|
// save the starting location as the first relative point |
localLastDragLocation=clickLocation; |
|
while (loop) { |
// get the next event that is a mouse-up or mouse-dragged event |
NSEvent *localEvent; |
localEvent= [[self window] nextEventMatchingMask:NSLeftMouseUpMask | NSLeftMouseDraggedMask]; |
|
|
switch ([localEvent type]) { |
case NSLeftMouseDragged: |
|
// convert the new drag location into the view coords |
newDragLocation = [self convertPoint:[localEvent locationInWindow] |
fromView:nil]; |
|
|
// offset the item and update the display |
[self offsetLocationByX:(float)(newDragLocation.x-localLastDragLocation.x) |
andY:(float)(newDragLocation.y-localLastDragLocation.y)]; |
|
// update the relative drag location; |
localLastDragLocation=newDragLocation; |
|
// support automatic scrolling during a drag |
// by calling NSView's autoscroll: method |
[self autoscroll:localEvent]; |
|
break; |
case NSLeftMouseUp: |
// mouse up has been detected, |
// we can exit the loop |
loop = NO; |
|
// finished dragging, restore the cursor |
[NSCursor pop]; |
|
// the rectangle has moved, we need to reset our cursor |
// rectangle |
[[self window] invalidateCursorRectsForView:self]; |
|
break; |
default: |
// Ignore any other kind of event. |
break; |
} |
} |
}; |
return; |
} |
|
|
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// ----------------------------------- |
// First Responder Methods |
// ----------------------------------- |
|
- (BOOL)acceptsFirstResponder |
{ |
return YES; |
} |
|
|
|
// ----------------------------------- |
// Handle KeyDown Events |
// ----------------------------------- |
|
|
- (void)keyDown:(NSEvent *)event |
{ |
BOOL handled = NO; |
NSString *characters; |
|
// get the pressed key |
characters = [event charactersIgnoringModifiers]; |
|
// is the "r" key pressed? |
if ([characters isEqual:@"r"]) { |
// Yes, it is |
handled = YES; |
|
// set the rectangle properties |
[self setItemPropertiesToDefault:self]; |
} |
if (!handled) |
[super keyDown:event]; |
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} |
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// ----------------------------------- |
// Handle NSResponder Actions |
// ----------------------------------- |
|
-(IBAction)moveUp:(id)sender |
{ |
[self offsetLocationByX:0.0f andY:10.0f]; |
[[self window] invalidateCursorRectsForView:self]; |
} |
|
-(IBAction)moveDown:(id)sender |
{ |
[self offsetLocationByX:0.0f andY:-10.0f]; |
[[self window] invalidateCursorRectsForView:self]; |
} |
|
-(IBAction)moveLeft:(id)sender |
{ |
[self offsetLocationByX:-10.0f andY:0.0f]; |
[[self window] invalidateCursorRectsForView:self]; |
} |
|
-(IBAction)moveRight:(id)sender |
{ |
[self offsetLocationByX:10.0f andY:0.0f]; |
[[self window] invalidateCursorRectsForView:self]; |
} |
|
- (IBAction)setItemPropertiesToDefault:(id)sender |
{ |
[self setLocation:NSMakePoint(0.0f,0.0f)]; |
[self setItemColor:[NSColor redColor]]; |
[self setBackgroundColor:[NSColor whiteColor]]; |
} |
|
|
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// ----------------------------------- |
// Handle color changes via first responder |
// ----------------------------------- |
|
- (void)changeColor:(id)sender |
{ |
// Set the color in response |
// to the color changing in the color panel. |
// get the new color by asking the sender, the color panel |
[self setItemColor:[sender color]]; |
} |
|
|
|
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// ----------------------------------- |
// Reset Cursor Rects |
// ----------------------------------- |
|
-(void)resetCursorRects |
{ |
// remove the existing cursor rects |
[self discardCursorRects]; |
|
// add the draggable item's bounds as a cursor rect |
[self addCursorRect:[self calculatedItemBounds] cursor:[NSCursor openHandCursor]]; |
|
} |
|
// ----------------------------------- |
// Accessor Methods |
// ----------------------------------- |
|
- (void)setItemColor:(NSColor *)aColor |
{ |
if (![itemColor isEqual:aColor]) { |
[itemColor release]; |
itemColor = [aColor retain]; |
|
// if the colors are not equal, mark the |
// draggable rect as needing display |
[self setNeedsDisplayInRect:[self calculatedItemBounds]]; |
} |
} |
|
|
- (NSColor *)itemColor |
{ |
return [[itemColor retain] autorelease]; |
} |
|
- (void)setBackgroundColor:(NSColor *)aColor |
{ |
if (![backgroundColor isEqual:aColor]) { |
[backgroundColor release]; |
backgroundColor = [aColor retain]; |
|
// if the colors are not equal, mark the |
// draggable rect as needing display |
[self setNeedsDisplayInRect:[self calculatedItemBounds]]; |
} |
} |
|
|
- (NSColor *)backgroundColor |
{ |
return [[backgroundColor retain] autorelease]; |
} |
|
|
- (void)setLocation:(NSPoint)point |
{ |
// test to see if the point actually changed |
if (!NSEqualPoints(point,location)) { |
// tell the display to redraw the old rect |
[self setNeedsDisplayInRect:[self calculatedItemBounds]]; |
|
// reassign the rect |
location=point; |
|
// display the new rect |
[self setNeedsDisplayInRect:[self calculatedItemBounds]]; |
|
// invalidate the cursor rects |
[[self window] invalidateCursorRectsForView:self]; |
} |
} |
|
- (NSPoint)location { |
return location; |
} |
|
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- (NSRect)calculatedItemBounds |
{ |
NSRect calculatedRect; |
|
// calculate the bounds of the draggable item |
// relative to the location |
calculatedRect.origin=location; |
|
// the example assumes that the width and height |
// are fixed values |
calculatedRect.size.width=60.0f; |
calculatedRect.size.height=20.0f; |
|
return calculatedRect; |
} |
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@end |
