封装CoreGraphics的API简化绘图操作

封装CoreGraphics的API简化绘图操作

效果

说明

1. 将CoreGraphics的API接口抽象为对象,让绘图变得简单易懂

2. 简化常用的绘制操作

3. 源码长期更新

源码

https://github.com/YouXianMing/CGContextObject

//
//  CGContextObject.h
//  DrawRect
//
//  Created by YouXianMing on 15/7/2.
//  Copyright (c) 2015年 YouXianMing. All rights reserved.
//

#import <Foundation/Foundation.h>
#import <CoreGraphics/CoreGraphics.h>
#import "RGBColor.h"
#import "GradientColor.h"
@class CGContextObject;


typedef void(^CGContextObjectDrawBlock_t)(CGContextObject *contextObject);


@interface CGContextObject : NSObject

/**
 *  操作句柄
 */
@property (nonatomic)          CGContextRef   context;

/**
 *  线头样式
 */
@property (nonatomic)          CGLineCap      lineCap;

/**
 *  线条宽度
 */
@property (nonatomic)          CGFloat        lineWidth;

/**
 *  线条颜色
 */
@property (nonatomic, strong)  RGBColor      *strokeColor;

/**
 *  填充颜色
 */
@property (nonatomic, strong)  RGBColor      *fillColor;

/**
 *  由context进行初始化
 *
 *  @param context 绘制句柄
 *
 *  @return 绘制对象
 */
- (instancetype)initWithCGContext:(CGContextRef)context;

#pragma mark - 绘制操作流程
/**
 *  开始path
 */
- (void)beginPath;

/**
 *  关闭path
 */
- (void)closePath;

/**
 *  线条绘制
 */
- (void)strokePath;

/**
 *  填充绘制
 */
- (void)fillPath;

/**
 *  线条绘制 + 填充绘制
 */
- (void)strokeAndFillPath;

/**
 *  绘制线条用block (beginPath + closePath + 你绘制的代码 + strokePath)
 *
 *  @param block 绘制用block
 */
- (void)drawStrokeBlock:(CGContextObjectDrawBlock_t)block;

/**
 *  填充区域用block (beginPath + closePath + 你绘制的代码 + fillPath)
 *
 *  @param block 填充用block
 */
- (void)drawFillBlock:(CGContextObjectDrawBlock_t)block;

/**
 *  绘制加填充
 *
 *  @param block 绘制加填充用block
 */
- (void)drawStrokeAndFillBlock:(CGContextObjectDrawBlock_t)block;

/**
 *  绘制线条用block (beginPath + closePath + 你绘制的代码 + strokePath)
 *
 *  @param block     绘制用block
 *  @param closePath 是否关闭曲线
 */
- (void)drawStrokeBlock:(CGContextObjectDrawBlock_t)block closePath:(BOOL)closePath;

/**
 *  填充区域用block (beginPath + closePath + 你绘制的代码 + fillPath)
 *
 *  @param block     绘制用block
 *  @param closePath 是否关闭曲线
 */
- (void)drawFillBlock:(CGContextObjectDrawBlock_t)block closePath:(BOOL)closePath;

/**
 *  绘制加填充
 *
 *  @param block     绘制用block
 *  @param closePath 是否关闭曲线
 */
- (void)drawStrokeAndFillBlock:(CGContextObjectDrawBlock_t)block closePath:(BOOL)closePath;

#pragma mark - 绘制图片API

- (void)drawImage:(UIImage *)image atPoint:(CGPoint)point;
- (void)drawImage:(UIImage *)image atPoint:(CGPoint)point blendMode:(CGBlendMode)blendMode alpha:(CGFloat)alpha;
- (void)drawImage:(UIImage *)image inRect:(CGRect)rect;
- (void)drawImage:(UIImage *)image inRect:(CGRect)rect blendMode:(CGBlendMode)blendMode alpha:(CGFloat)alpha;
- (void)drawImage:(UIImage *)image asPatternInRect:(CGRect)rect;

#pragma mark - 保存操作

/**
 *  将当前设置存取到栈区中(入栈操作)
 */
- (void)saveStateToStack;

/**
 *  从栈区中取出之前保存的设置(出栈操作)
 */
- (void)restoreStateFromStack;

#pragma mark - 图形绘制API
/**
 *  移动到起始点
 *
 *  @param point 起始点
 */
- (void)moveToStartPoint:(CGPoint)point;

/**
 *  添加一个点(与上一个点直线相连)
 *
 *  @param point 点
 */
- (void)addLineToPoint:(CGPoint)point;

/**
 *  添加二次贝塞尔曲线
 *
 *  @param point    结束点
 *  @param pointOne 控制点1
 *  @param pointTwo 控制点2
 */
- (void)addCurveToPoint:(CGPoint)point controlPointOne:(CGPoint)pointOne controlPointTwo:(CGPoint)pointTwo;

/**
 *  添加一次贝塞尔曲线
 *
 *  @param point        结束点
 *  @param controlPoint 控制点
 */
- (void)addQuadCurveToPoint:(CGPoint)point controlPoint:(CGPoint)controlPoint;

/**
 *  在指定的区域填充彩色的矩形（此为直接绘制）
 *
 *  @param rect          指定的区域
 *  @param gradientColor 渐变色对象
 */
- (void)drawLinearGradientAtClipToRect:(CGRect)rect gradientColor:(GradientColor *)gradientColor;

#pragma mark - 
/**
 *  添加一个矩形
 *
 *  @param rect
 */
- (void)addRect:(CGRect)rect;

/**
 *  在给定的矩形中绘制椭圆
 *
 *  @param rect
 */
- (void)addEllipseInRect:(CGRect)rect;

/**
 *  将string绘制在指定的点上
 *
 *  @param string     字符串
 *  @param point      点
 *  @param attributes 富文本设置（可以为空）
 */
- (void)drawString:(NSString *)string atPoint:(CGPoint)point withAttributes:(NSDictionary *)attributes;

/**
 *  将string绘制在制定的区域
 *
 *  @param string     字符串
 *  @param rect       区域
 *  @param attributes 富文本设置（可以为空）
 */
- (void)drawString:(NSString *)string inRect:(CGRect)rect withAttributes:(NSDictionary *)attributes;

/**
 *  将富文本绘制在制定的点上
 *
 *  @param string 富文本
 *  @param point  点
 */
- (void)drawAttributedString:(NSAttributedString *)string atPoint:(CGPoint)point;

/**
 *  将富文本绘制在制定的矩形中
 *
 *  @param string 富文本
 *  @param rect   矩形
 */
- (void)drawAttributedString:(NSAttributedString *)string inRect:(CGRect)rect;

@end

//
//  CGContextObject.m
//  DrawRect
//
//  Created by YouXianMing on 15/7/2.
//  Copyright (c) 2015年 YouXianMing. All rights reserved.
//

#import "CGContextObject.h"

@interface CGContextObject ()

@end

@implementation CGContextObject

- (instancetype)initWithCGContext:(CGContextRef)context {
    
    self = [super init];
    if (self) {
        
        self.context = context;
    }
    
    return self;
}

- (void)moveToStartPoint:(CGPoint)point {
    
    if (_context) {
        CGContextMoveToPoint(_context, point.x, point.y);
    }
}

- (void)addLineToPoint:(CGPoint)point {
    
    if (_context) {
        CGContextAddLineToPoint(_context, point.x, point.y);
    }
}

- (void)addCurveToPoint:(CGPoint)point controlPointOne:(CGPoint)pointOne controlPointTwo:(CGPoint)pointTwo {

    if (_context) {
        CGContextAddCurveToPoint(_context, pointOne.x, pointOne.y, pointTwo.x, pointTwo.y, point.x, point.y);
    }
}

- (void)addQuadCurveToPoint:(CGPoint)point controlPoint:(CGPoint)controlPoint {
    
    if (_context) {
        CGContextAddQuadCurveToPoint(_context, controlPoint.x, controlPoint.y, point.x, point.y);
    }
}

- (void)drawLinearGradientAtClipToRect:(CGRect)rect gradientColor:(GradientColor *)gradientColor {
    
    [self saveStateToStack];
    
    
    if (_context) {
        
        CGContextClipToRect(_context, rect);
        
        CGContextDrawLinearGradient(_context,
                                    gradientColor.gradientRef,
                                    gradientColor.gradientStartPoint,
                                    gradientColor.gradientEndPoint, kCGGradientDrawsBeforeStartLocation);
    }
    
    
    [self restoreStateFromStack];
}

- (void)addRect:(CGRect)rect {

    if (_context) {
        CGContextAddRect(_context, rect);
    }
}

- (void)addEllipseInRect:(CGRect)rect {
    
    if (_context) {
        CGContextAddEllipseInRect(_context, rect);
    }
}

- (void)drawString:(NSString *)string atPoint:(CGPoint)point withAttributes:(NSDictionary *)attributes {

    [string drawAtPoint:point withAttributes:attributes];
}

- (void)drawString:(NSString *)string inRect:(CGRect)rect withAttributes:(NSDictionary *)attributes {

    [string drawInRect:rect withAttributes:attributes];
}

- (void)drawAttributedString:(NSAttributedString *)string atPoint:(CGPoint)point {

    [string drawAtPoint:point];
}

- (void)drawAttributedString:(NSAttributedString *)string inRect:(CGRect)rect {

    [string drawInRect:rect];
}

- (void)beginPath {
    
    if (_context) {
        CGContextBeginPath(_context);
    }
}

- (void)closePath {

    if (_context) {
        CGContextClosePath(_context);
    }
}

- (void)strokePath {

    if (_context) {
        CGContextStrokePath(_context);
    }
}

- (void)fillPath {

    if (_context) {
        CGContextFillPath(_context);
    }
}

- (void)strokeAndFillPath {

    if (_context) {
        CGContextDrawPath(_context, kCGPathFillStroke);
    }
}

- (void)drawStrokeBlock:(CGContextObjectDrawBlock_t)block {

    [self beginPath];
    
    __weak CGContextObject *weakSelf = self;
    
    block(weakSelf);
    
    [self closePath];
    
    [self strokePath];
}

- (void)drawFillBlock:(CGContextObjectDrawBlock_t)block {
    
    [self beginPath];
    
    __weak CGContextObject *weakSelf = self;
    
    block(weakSelf);
    
    [self closePath];
    
    [self fillPath];
}

- (void)drawStrokeAndFillBlock:(CGContextObjectDrawBlock_t)block {

    [self beginPath];
    
    __weak CGContextObject *weakSelf = self;
    
    block(weakSelf);
    
    [self closePath];
    
    [self strokeAndFillPath];
}

- (void)drawStrokeBlock:(CGContextObjectDrawBlock_t)block closePath:(BOOL)closePath {

    [self beginPath];
    
    __weak CGContextObject *weakSelf = self;
    
    block(weakSelf);
    
    if (closePath) {
        [self closePath];
    }
    
    [self strokePath];
}

- (void)drawFillBlock:(CGContextObjectDrawBlock_t)block closePath:(BOOL)closePath {

    [self beginPath];
    
    __weak CGContextObject *weakSelf = self;
    
    block(weakSelf);
    
    if (closePath) {
        [self closePath];
    }
    
    [self fillPath];
}

- (void)drawStrokeAndFillBlock:(CGContextObjectDrawBlock_t)block closePath:(BOOL)closePath {

    [self beginPath];
    
    __weak CGContextObject *weakSelf = self;
    
    block(weakSelf);
    
    if (closePath) {
        [self closePath];
    }
    
    [self strokeAndFillPath];
}

- (void)drawImage:(UIImage *)image atPoint:(CGPoint)point {

    [image drawAtPoint:point];
}

- (void)drawImage:(UIImage *)image atPoint:(CGPoint)point blendMode:(CGBlendMode)blendMode alpha:(CGFloat)alpha {

    [image drawAtPoint:point blendMode:blendMode alpha:alpha];
}

- (void)drawImage:(UIImage *)image inRect:(CGRect)rect {

    [image drawInRect:rect];
}

- (void)drawImage:(UIImage *)image inRect:(CGRect)rect blendMode:(CGBlendMode)blendMode alpha:(CGFloat)alpha {

    [image drawInRect:rect blendMode:blendMode alpha:alpha];
}

- (void)drawImage:(UIImage *)image asPatternInRect:(CGRect)rect {

    [image drawAsPatternInRect:rect];
}

- (void)saveStateToStack {
    
    if (_context) {
        CGContextSaveGState(_context);
    }
}

- (void)restoreStateFromStack {
    
    if (_context) {
        CGContextRestoreGState(_context);
    }
}

#pragma mark - 重写setter,getter方法
@synthesize strokeColor = _strokeColor;
- (void)setStrokeColor:(RGBColor *)strokeColor {

    if (_context) {
        
        _strokeColor = strokeColor;
        CGContextSetRGBStrokeColor(_context, strokeColor.red, strokeColor.green, strokeColor.blue, strokeColor.alpha);
    }
}
- (RGBColor *)strokeColor {

    return _strokeColor;
}

@synthesize fillColor = _fillColor;
- (void)setFillColor:(RGBColor *)fillColor {
    
    if (_context) {
        
        _fillColor = fillColor;
        CGContextSetRGBFillColor(_context, fillColor.red, fillColor.green, fillColor.blue, fillColor.alpha);
    }
}
- (RGBColor *)fillColor {
    
    return _fillColor;
}

@synthesize lineWidth = _lineWidth;
- (void)setLineWidth:(CGFloat)lineWidth {
    
    if (_context) {
        
        _lineWidth = lineWidth;
        CGContextSetLineWidth(_context, lineWidth);
    }
}
- (CGFloat)lineWidth {
    
    return _lineWidth;
}

@synthesize lineCap = _lineCap;
- (void)setLineCap:(CGLineCap)lineCap {
    
    if (_context) {
    
        _lineCap = lineCap;
        CGContextSetLineCap(_context, lineCap);
    }
    
}
- (CGLineCap)lineCap {

    return _lineCap;
}

@end

细节