ios 三种颜色画笔和橡皮擦的画图板demo
demo功能：三种颜色画笔和橡皮擦的画图板demo 【iphone 6.1 测试通过】
demo说明：项目中PaintView.m 是demo的画板部分，PaintView和三个颜色按钮添加到ViewController的view中。构成程序主界面。
demo截屏：
demo主要代码：PaintView.m 画板view部分
#import "PaintView.h"
#import <QuartzCore/QuartzCore.h>
@implementation PaintView
@synthesize paintColor = _paintColor;
@synthesize erase;
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
self.layer.shadowColor = [UIColor blackColor].CGColor;
self.layer.shadowOpacity = 0.8;
self.layer.shadowOffset = CGSizeMake(5, 5);
self.backgroundColor = [UIColor whiteColor];
self.paintColor = [UIColor blackColor];
// Initialization code
linesArray = [[NSMutableArray alloc]init];
UIPanGestureRecognizer *panGesture = [[UIPanGestureRecognizer alloc]initWithTarget:self
action:@selector(panGesture:)];
[self addGestureRecognizer:panGesture];
[panGesture release];
}
return self;
}
- (void)dealloc {
[linesArray release];
[_paintColor release];
[super dealloc];
}
// Only override drawRect: if you perform custom drawing.
// An empty implementation adversely affects performance during animation.
- (void)drawRect:(CGRect)rect
{
// Drawing code
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetLineWidth(context, 20);
//NSLog(@"color:%@",_paintColor);
for (NSDictionary *lineDic in linesArray) {
UIColor *lineColor = [lineDic objectForKey:@"color"];
CGContextSetStrokeColorWithColor(context, lineColor.CGColor);
CGMutablePathRef paintPath = CGPathCreateMutable();
NSArray *linePointArray = [lineDic objectForKey:@"line"];
for (NSInteger i=0; i<linePointArray.count; i++) {
CGPoint point = [[linePointArray objectAtIndex:i]CGPointValue];
if (i==0) {
//CGContextMoveToPoint(context, point.x, point.y);
CGPathMoveToPoint(paintPath, NULL, point.x, point.y);
}else {
//CGContextAddLineToPoint(context, point.x, point.y);
CGPathAddLineToPoint(paintPath, NULL, point.x, point.y);
}
}
CGContextAddPath(context, paintPath);
CGContextStrokePath(context);
if ([lineDic objectForKey:@"eraseArray"]) {
//NSLog(@"color:%@",lineColor);
NSMutableArray *eraseArray = [lineDic objectForKey:@"eraseArray"];
CGContextSetStrokeColorWithColor(context, [UIColor whiteColor].CGColor);
CGMutablePathRef paintPath = CGPathCreateMutable();
for (NSInteger i=0; i<eraseArray.count; i++) {
CGPoint point = [[eraseArray objectAtIndex:i]CGPointValue];
//NSLog(@"erase point:%@",NSStringFromCGPoint(point));
if (i==0) {
//CGContextMoveToPoint(context, point.x, point.y);
CGPathMoveToPoint(paintPath, NULL, point.x, point.y);
}else {
//CGContextAddLineToPoint(context, point.x, point.y);
CGPathAddLineToPoint(paintPath, NULL, point.x, point.y);
}
}
CGContextAddPath(context, paintPath);
CGContextStrokePath(context);
}
}
}
-(void)panGesture:(UIPanGestureRecognizer*)thePan{
CGPoint touchPoint = [thePan locationInView:self];
if (self.erase) {
if (thePan.state==UIGestureRecognizerStateChanged) {
for (NSMutableDictionary *lineDic in linesArray) {
NSMutableArray *linePointArray = [lineDic objectForKey:@"line"];
for (NSInteger i=0; i<linePointArray.count; i++) {
CGPoint point = [[linePointArray objectAtIndex:i]CGPointValue];
CGFloat distance = powf(point.x-touchPoint.x,point.y-touchPoint.y);
if (distance<20) {
NSMutableArray *eraseArray;
if ([lineDic objectForKey:@"eraseArray"]) {
eraseArray = [lineDic objectForKey:@"eraseArray"];
}else {
eraseArray = [NSMutableArray array];
}
[eraseArray addObject:[NSValue valueWithCGPoint:touchPoint]];
[lineDic setObject:eraseArray forKey:@"eraseArray"];
CGRect paintRect = CGRectMake(touchPoint.x-50, touchPoint.y-50, 100, 100);
[self setNeedsDisplayInRect:paintRect];
//[self setNeedsDisplay];
continue;
}
}
}
}
//[self eraseLine:currentLineDic erase:[thePan locationInView:self]];
}else {
if (thePan.state==UIGestureRecognizerStateBegan) {
NSMutableArray *currentLineArray = [NSMutableArray arrayWithObject:[NSValue valueWithCGPoint:touchPoint]];
NSMutableDictionary *lineDic = [NSMutableDictionary dictionaryWithObjectsAndKeys:currentLineArray,@"line",_paintColor,@"color", nil];
[linesArray addObject:lineDic];
}else if(thePan.state==UIGestureRecognizerStateChanged){
NSMutableDictionary *lineDic = [linesArray lastObject];
NSMutableArray *currentLineArray = [lineDic objectForKey:@"line"];
[currentLineArray addObject:[NSValue valueWithCGPoint:touchPoint]];
CGRect paintRect = CGRectMake(touchPoint.x-50, touchPoint.y-50, 100, 100);
[self setNeedsDisplayInRect:paintRect];
}else if(thePan.state==UIGestureRecognizerStateEnded){
}
}
}
@end
demo下载地址：http://download.csdn.net/detail/donny_zhang/5572237