iOS应用开发——小画板Demo.doc

iOS应用开发小画板Demo代码部分TouchView.h1#import23interfaceTouchView:UIView45NSMutableArray*points;6NSArray*points_all;7CGContextRefcontext;8UIColor*paint_clr;910property(strong,nonatomic)NSMutableArray*points;11property(strong,nonatomic)NSArray*points_all;12property(strong,nonatomic)UIColor*paint_clr;1314endTouchView.m1#importTouchView.h23implementationTouchView4synthesizepoints,points_all,paint_clr;56-(id)initWithFrame:(CGRect)frame78self=superinitWithFrame:frame;9if(self)10/Initializationcode11paint_clr=UIColorgreenColor;1213returnself;141516/OnlyoverridedrawRect:ifyouperformcustomdrawing.17/Anemptyimplementationadverselyaffectsperformanceduringanimation.18-(void)drawRect:(CGRect)rect1920/Drawingcode21if(!self.points)|(self.points.count2)22return;232425context=UIGraphicsGetCurrentContext();26/设置画笔粗细27CGContextSetLineWidth(context,5.0f);28/设置画笔颜色29/UIColorblueColorset;30/paint_clrset;31/CGContextSetStrokeColorWithColor(context,UIColorblueColorCGColor);32CGContextSetStrokeColorWithColor(context,paint_clrCGColor);3334/画以前的轨迹35for(intj=0;jself.points_allcount;j+)36NSMutableArray*points_tmp=points_allobjectAtIndex:j;3738for(inti=0;ipoints_tmpcount-1;i+)3940CGPointpoint1=points_tmpobjectAtIndex:iCGPointValue;41CGPointpoint2=points_tmpobjectAtIndex:(i+1)CGPointValue;42CGContextMoveToPoint(context,point1.x,point1.y);43CGContextAddLineToPoint(context,point2.x,point2.y);44CGContextStrokePath(context);45464748/画这次49for(inti=0;iself.pointscount-1;i+)50CGPointpoint1=self.pointsobjectAtIndex:iCGPointValue;51CGPointpoint2=self.pointsobjectAtIndex:(i+1)CGPointValue;52CGContextMoveToPoint(context,point1.x,point1.y);53CGContextAddLineToPoint(context,point2.x,point2.y);54CGContextStrokePath(context);55565758/不支持多点触摸59-(BOOL)isMultipleTouchEnabled6061returnNO;626364/创建一个array，并且记录初始ponit65-(void)touchesBegan:(NSSet*)toucheswithEvent:(UIEvent*)event6667self.points=NSMutableArrayarray;68CGPointpt=touchesanyObjectlocationInView:self;69self.pointsaddObject:NSValuevalueWithCGPoint:pt;707172/移动过程中记录这些points73/调用setNeedsDisplay，会触发drawRect方法的调用74-(void)touchesMoved:(NSSet*)toucheswithEvent:(UIEvent*)event7576CGPointpt=touchesanyObjectlocationInView:self;77self.pointsaddObject:NSValuevalueWithCGPoint:pt;78selfsetNeedsDisplay;798081-(void)touchesEnded:(NSSet*)toucheswithEvent:(UIEvent*)event8283NSMutableArray*points_tmp=NSMutableArrayallocinitWithArray:self.points;84if(self.points_all=nil)85self.points_all=NSArrayallocinitWithObjects:points_tmp,nil;86else87self.points_all=self.points_allarrayByAddingObject:points_tmp;888990endViewController.h1#import23classTouchView;4interfaceViewController:UIViewController56TouchView*tv;78endViewController.m1#importViewController.h2#importTouchView.h34interfaceViewController()56end78implementationViewController910-(void)viewDidLoad1112superviewDidLoad;13/Doanyadditionalsetupafterloadingtheview,typicallyfromanib.14self.view.userInteractionEnabled=YES;1516/TouchView*tv=TouchViewallocinitWithFrame:CGRectMake(0.0f,0.0f,260.0f,260.0f);17tv=TouchViewallocinitWithFrame:self.view.frame;18tv.backgroundColor=UIColorblackColor;1920self.viewaddSubview:tv;2122UISegmentedControl*seg=UISegmentedControlallocinitWithItems:WhiteRedBlueGreenYellowcomponentsSeparatedByString:;23seg.segmentedControlStyle=UISegmentedControlSegmentCenter;24seg.tintColor=UIColorblackColor;25seg.center=CGPointMake(self.view.center.x,(self.view.bounds.size.height-seg.bounds.size.height);26self.viewaddSubview:seg;2728segaddTarget:selfaction:selector(colorChange:)forControlEvents:UIControlEventValueChanged;293031-(void)viewDidUnload3233superviewDidUnload;34/Releaseanyretainedsubviewsofthemainview.353637-(BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation3839return(interfaceOrientation!=UIInterfaceOrientationPortraitUpsideDown);404142-(void)colorChange:(UISegmentedControl*)seg4344switch(segselectedSegmentIndex)4546case0:47tv.paint_clr=UIColorwhiteColor;48break;49case1:50tv.paint