概要
本章主要简示了使用IOS的绘图Quartz，包括简单的画直线、图片、文字、圆、矩形、贝塞尔曲线，包括一些基本使用方法。
结果展示
流程概要
1.绘图好像直接在UIView类里面绘制的，在控制类里面绘制没有尝试。
2.新建一个基于UIView的类，发现新建类里面自动生成了drawRect方法，直接在这个方法里面写代码即可自动被调用
3.注意绘图时是先绘制路径，然后使用画图函数（eg.CGContextDrawPath,CGContextFillPath等）才能在界面上显示。
主要代码
基于UIView的类的m文件
//
// MyView.m
// CustomDraw
//
// Created by arbboter on 14/12/18.
// Copyright (c) 2014年 arbboter. All rights reserved.
//
#import "MyView.h"
@interface MyView ()
@property (nonatomic, readwrite) CGRect myFrame;
@end
@implementation MyView
- (void) setMyFrame
{
CGFloat x = self.frame.origin.x;
CGFloat y = self.frame.origin.y;
CGFloat w = self.frame.size.width;
CGFloat h = self.frame.size.height;
x = x + 5;
y = y + 20 ;
w = w - 10;
h = h - 25;
_myFrame = CGRectMake(x, y, w, h);
}
/** 该方法是UIView内置方法 */
- (void) drawRect:(CGRect)rect
{
// 设置绘图区域
[self setMyFrame];
/** 画图 */
NSString* filePath = [[NSBundle mainBundle] pathForResource:@"sad" ofType:@"jpeg"];
UIImage* image = [[UIImage alloc] initWithContentsOfFile:filePath];
[image drawAtPoint:CGPointMake(self.frame.origin.x, self.frame.origin.y)];
[image release];
image = nil;
/** 写字(设置字体大小及颜色) */
NSArray* array = [UIFont familyNames];
UIFont* font = [UIFont fontWithName:[array objectAtIndex:35] size:42];
NSDictionary* dict = [[NSDictionary alloc] initWithObjectsAndKeys:font, NSFontAttributeName,
[UIColor blueColor], NSForegroundColorAttributeName,
nil];
NSString* title = [[NSString alloc] initWithString:@"正余弦曲线"];
[title drawAtPoint:CGPointMake(95, 35) withAttributes:dict];
[dict release];
dict = nil;
CGFloat x = self.myFrame.origin.x;
CGFloat y = self.myFrame.origin.y;
CGFloat w = self.myFrame.size.width;
CGFloat h = self.myFrame.size.height;
CGContextRef ctx = UIGraphicsGetCurrentContext();
/** ==画矩形框== */
/** 设置路径 */
CGContextMoveToPoint(ctx, x, y);
CGContextAddLineToPoint(ctx, x + w, y);
CGContextAddLineToPoint(ctx, x + w, y + h);
CGContextAddLineToPoint(ctx, x, y + h);
CGContextAddLineToPoint(ctx, x, y);
/** 设置画图颜色 */
[[UIColor blackColor] setStroke];
/** 设置画笔大小 */
CGContextSetLineWidth(ctx, 2.0);
/** 根据设置的路径画路径 */
CGContextStrokePath(ctx);
/** ==画矩形块== */
/* 设置路径 */
CGContextMoveToPoint(ctx, x + w - 50, y + 5);
CGContextAddLineToPoint(ctx, x + w - 10, y + 5);
CGContextAddLineToPoint(ctx, x + w - 10, y + 45);
CGContextAddLineToPoint(ctx, x + w - 50, y + 45);
/* 可选择自己绘制闭合路径, 也可使用CGContextClosePath自动绘制 */
#if 0
/* 绘制闭合路径 */
CGContextAddLineToPoint(ctx, x + 5, y + 5);
#else
/** 自动绘制闭合路径 */
CGContextClosePath(ctx);
#endif
/* 设置绘图画笔颜色 */
[[UIColor yellowColor] setStroke];
/* 设置绘图填充颜色 */
[[UIColor redColor] setFill];
/** 设置画笔大小 */
CGContextSetLineWidth(ctx, 1.0);
/* 绘制方式绘画
* kCGPathFillStroke -> 填充+描边
* kCGPathFill -> 填充
* kCGPathStroke -> 描边
*/
CGContextDrawPath(ctx, kCGPathFillStroke);
/** ==画下边框的圆还== */
CGFloat r1 = 12;
CGFloat r2 = 6;
CGFloat x1 = x + r1 + 2;
CGFloat y1 = y + h - r1 -2;
for (CGFloat xMax=x1+r1; xMax < x + w; xMax=x1+r1)
{
/** 通过先绘制大圆，然后再绘制和背景色相同的小圆实现圆环绘制 */
/** 移动到圆周上一点,不然会把当前圆和之前的最后点连接起来 */
CGContextMoveToPoint(ctx, x1+r1, y1);
/* 绘制大圆路径 */
CGContextAddArc(ctx, x1, y1, r1, 0, M_PI*2, 0);
/* 设置颜色 */
CGContextSetFillColor(ctx, CGColorGetComponents([[UIColor blueColor] CGColor]));
CGContextSetStrokeColor(ctx, CGColorGetComponents([[UIColor greenColor] CGColor]));
/** 绘制图形 */
CGContextDrawPath(ctx, kCGPathFillStroke);
/** 移动到圆周上一点 */
CGContextMoveToPoint(ctx, x1+r2, y1);
/** 绘制小圆路径 */
CGContextAddArc(ctx, x1, y1, r2, 0, M_PI*2, 0);
/** 设置小圆填充颜色[颜色值用系统自带的数码测色器获取背景色] */
[[UIColor colorWithRed:170.0/255 green:166.0/255 blue:102.0/255 alpha:1.0] setFill];
/** 绘制图形 */
CGContextFillPath(ctx);
x1 += (2*r1+2);
}
[self drawCoordinate];
[self drawSin];
}
/** 绘制坐标轴 */
- (void) drawCoordinate
{
CGFloat x = self.myFrame.origin.x;
CGFloat y = self.myFrame.origin.y;
CGFloat w = self.myFrame.size.width;
CGFloat h = self.myFrame.size.height;
/* 坐标系原点 */
CGFloat x1 = x + 5 + 20;
CGFloat y1 = y + h - 40;
CGContextRef ctx = UIGraphicsGetCurrentContext();
/** 设置绘图颜色 */
CGContextSetStrokeColorWithColor(ctx, [[UIColor blackColor] CGColor]);
CGContextSetLineWidth(ctx, 3.0);
/** 设置标准字体 */
/** 写字(设置字体大小及颜色) */
NSArray* array = [UIFont familyNames];
UIFont* font = [UIFont fontWithName:[array objectAtIndex:1] size:12];
NSDictionary* dict = [[NSDictionary alloc] initWithObjectsAndKeys:font, NSFontAttributeName,
[UIColor redColor], NSForegroundColorAttributeName,
nil];
/** 先绘制坐标 */
CGContextMoveToPoint(ctx, x1, y1);
/** 横坐标系 */
CGContextAddLineToPoint(ctx, x + w, y1);
CGContextStrokePath(ctx);
/* 绘制尺寸标注 */
CGFloat h1 = 0;
NSInteger wid = 20;
for (NSInteger x2= x1+wid; x2 < x1 + w; x2+=wid)
{
NSInteger num = (x2 - x1)/wid;
if( num%2 )
{
h1 = 4;
CGContextSetLineWidth(ctx, 1.0);
}
else
{
h1 = 6;
CGContextSetLineWidth(ctx, 2.0);
NSString* strNum = [[NSString alloc] initWithFormat:@"%ld", num/2];
[strNum drawAtPoint:CGPointMake(x2, y1) withAttributes:dict];
[strNum release];
}
CGContextMoveToPoint(ctx, x2, y1-2);
CGContextAddLineToPoint(ctx, x2, y1-h1);
CGContextStrokePath(ctx);
}
/** 纵坐标系 */
CGContextSetStrokeColorWithColor(ctx, [[UIColor blackColor] CGColor]);
CGContextSetLineWidth(ctx, 3.0);
CGContextMoveToPoint(ctx, x1, y1+1.5);
CGContextAddLineToPoint(ctx, x1, y);
CGContextStrokePath(ctx);
/* 绘制尺寸标注 */
for (NSInteger y2=y1-wid; y2 > y; y2-=wid)
{
NSInteger num = (y1 - y2)/wid;
if( num%2 )
{
h1 = 4;
CGContextSetLineWidth(ctx, 1.0);
}
else
{
h1 = 6;
CGContextSetLineWidth(ctx, 2.0);
if (num>1)
{
NSString* strNum = [[NSString alloc] initWithFormat:@"%ld", num/2];
[strNum drawAtPoint:CGPointMake(x1-20, y2-6) withAttributes:dict];
[strNum release];
}
}
CGContextMoveToPoint(ctx, x1+2, y2);
CGContextAddLineToPoint(ctx, x1+h1, y2);
CGContextStrokePath(ctx);
}
[dict release];
dict = nil;
}
- (void) drawSin
{
/** 使用二阶贝塞尔曲线模拟正余弦 */
CGFloat x = self.myFrame.origin.x;
CGFloat y = self.myFrame.origin.y;
CGFloat w = self.myFrame.size.width;
CGFloat h = self.myFrame.size.height;
/* 坐标系原点 */
CGFloat x1 = x + 5 + 20;
CGFloat y1 = y + h - 40;
CGFloat w1 = 20;
CGFloat h1 = 200;
CGContextRef ctx = UIGraphicsGetCurrentContext();
/** 正弦 */
CGContextSetStrokeColorWithColor(ctx, [[UIColor redColor] CGColor]);
CGFloat yShift = -300;
for (CGFloat x2=x1-2*w1; x2<x+w; x2+=2*w1)
{
h1 *= -1;
CGContextMoveToPoint(ctx, x2, y1+yShift);
CGContextAddQuadCurveToPoint(ctx, x2+w1, y1-h1+yShift, x2+2*w1, y1+yShift);
CGContextStrokePath(ctx);
}
/** 余弦 */
CGContextSetStrokeColorWithColor(ctx, [[UIColor yellowColor] CGColor]);
for (CGFloat x2=x1-w1; x2<x+w; x2+=2*w1)
{
CGContextMoveToPoint(ctx, x2, y1+yShift);
CGContextAddQuadCurveToPoint(ctx, x2+w1, y1-h1+yShift, x2+2*w1, y1+yShift);
CGContextStrokePath(ctx);
h1 *= -1;
}
/** 给曲线加个基线 */
/** 分别指定虚线的小实线和空白的长度 */
CGFloat fpDash[] = {5,5};
CGContextSetStrokeColorWithColor(ctx, [[UIColor blackColor] CGColor]);
CGContextSetLineWidth(ctx, 1.0);
/** 设置画线格式为虚线：参数含义
* context – 这个不用多说
* phase参数表示在第一个虚线绘制的时候跳过多少个点
* lengths – 指明虚线是如何交替绘制，上面的数组fpDash
* count – lengths数组的长度
*/
CGContextSetLineDash(ctx, 0, fpDash, 2);
CGContextMoveToPoint(ctx, 0, y1+yShift);
CGContextAddLineToPoint(ctx, x+w, y1+yShift);
CGContextStrokePath(ctx);
/** 文字标注 */
/** 写字(设置字体大小及颜色) */
NSArray* array = [UIFont familyNames];
UIFont* font = [UIFont fontWithName:[array objectAtIndex:20] size:16];
NSDictionary* dict = [[NSDictionary alloc] initWithObjectsAndKeys:font, NSFontAttributeName,
[UIColor redColor], NSForegroundColorAttributeName,
nil];
NSString* title = [[NSString alloc] initWithString:@"----正弦曲线"];
[title drawAtPoint:CGPointMake(x + w - 100, y + h/8) withAttributes:dict];
[dict release];
dict = nil;
dict = [[NSDictionary alloc] initWithObjectsAndKeys:font, NSFontAttributeName,
[UIColor yellowColor], NSForegroundColorAttributeName,
nil];
title = [[NSString alloc] initWithString:@"----余弦曲线"];
[title drawAtPoint:CGPointMake(x + w - 100, y + h/8 + 30) withAttributes:dict];
[dict release];
dict = nil;
}
@end
项目工程
时间： 2024-11-15 22:58:10