iphone自适应三维柱状图
点击柱状图中的 柱 可获取 该柱的编号（从左到右，0－n）
能自动调整 柱 的宽度以及各 柱 之间的间隔
1 //
2 // NTChartView.m
3 // chart
4 //
5 // Created by wml on 11－04－10.
6 // Copyright 2009 __MyCompanyName__. All rights reserved.
7 //
8
9 #import "NTChartView.h"
10 #import "Alerter.h"
11 #import "Rectangle.h"
12
13 static int MARGIN_LEFT = 50;
14 static int MARGIN_BOTTOM = 30;
15 static int MARGIN_TOP = 20;
16 static int SHOW_SCALE_NUM = 7;
17 static int WIDTH = 300;
18 static int HEIGHT = 300;
19
20 @interface NTChartView(private)
21 -(void)drawColumn:(CGContextRef)context rect:(CGRect)_rect;
22 -(void)drawScale:(CGContextRef)context rect:(CGRect)_rect;
23 -(void)calcScales:(CGRect)_rect;
24 @end
25
26 @implementation NTChartView
27 @synthesize groupData;
28 @synthesize groupRect;
29 @synthesize frstTouch;
30 @synthesize scndTouch;
31
32 - (void) dealloc
33 {
34 [groupRect release];
35 [groupData release];
36 [super dealloc];
37 }
38
39
40 -(void)drawRect:(CGRect)_rect{
41 WIDTH = _rect.size.width;
42 HEIGHT = _rect.size.height;
43 groupRect = [[NSMutableArray alloc] init];
44 MARGIN_LEFT = WIDTH/6.0;
45 MARGIN_BOTTOM = HEIGHT/10.0;
46 MARGIN_TOP = HEIGHT/15.0;
47
48 // the _rect is the Canvas on which the bar chart should be painted
49
50 //绘图上下文
51 CGContextRef context = UIGraphicsGetCurrentContext();
52 //设置画笔颜色
53 CGContextSetFillColorWithColor(context, [UIColor whiteColor].CGColor);
54 //为该矩形填充颜色
55 CGContextFillRect(context, _rect);
56
57 //计算刻度
58 [self calcScales:_rect];
59 //画刻度
60 [self drawScale:context rect:_rect];
61 //画柱
62 [self drawColumn:context rect:_rect];
63
64 }
65
66 -(void)drawScale:(CGContextRef)context rect:(CGRect)_rect{
67
68 //the coordinate axis
69 CGPoint points[3];
70 // the top "end" of the y-axis
71 points[0] = CGPointMake(MARGIN_LEFT - WIDTH/30, MARGIN_TOP);
72 // the coordinate center
73 points[1] = CGPointMake(MARGIN_LEFT -WIDTH/30, _rect.size.height - MARGIN_BOTTOM + 1);
74 // the right "end" of x-axis
75 points[2] = CGPointMake(_rect.size.width - WIDTH/30, _rect.size.height - MARGIN_BOTTOM + 1);
76 CGContextSetAllowsAntialiasing(context, NO);
77 CGContextAddLines(context, points, 3);
78 //the color of the scale number
79 CGContextSetFillColorWithColor(context, [UIColor blackColor].CGColor);
80
81 for(int i=1;i<SHOW_SCALE_NUM + 1; i++){
82 maxScaleHeight = (_rect.size.height - MARGIN_BOTTOM) * ( i ) / (SHOW_SCALE_NUM + 1);
83 int vScal = ceil(1.0 * maxScaleValue / (SHOW_SCALE_NUM ) * (i ));
84 //the y-axis value of the current scale
85 float y = (_rect.size.height - MARGIN_BOTTOM) - maxScaleHeight;
86
87 NSString *scaleStr = [NSString stringWithFormat:@"%d",vScal];
88
89 [scaleStr drawAtPoint:CGPointMake(MARGIN_LEFT - WIDTH/15.0 - [scaleStr sizeWithFont:[UIFont systemFontOfSize:10]].width, y - 7) withFont:[UIFont systemFontOfSize:10]];
90 //the short line to the right of the scale number
91 points[0] = CGPointMake(MARGIN_LEFT - WIDTH/30.0, y);// one end of the line
92 points[1] = CGPointMake(MARGIN_LEFT - WIDTH/30.0-3, y);// another end
93 CGContextSetLineDash(context, 0, NULL, 0);
94 CGContextAddLines(context, points, 2);
95
96 //draw those defined before
97 CGContextSetStrokeColorWithColor(context, [UIColor redColor].CGColor);
98 CGContextDrawPath(context, kCGPathStroke);
99
100 //the horizontal referring line
101 points[0] = CGPointMake(MARGIN_LEFT - WIDTH/30.0, y);
102 points[1] = CGPointMake(_rect.size.width - WIDTH/30.0 , y);
103 //the length of the painted line segments and unpainted
104 //{2,3} means a dotted line with the painted segments of length 2 pixel and ...
105 float partren[] = {2,3};
106 CGContextSetStrokeColorWithColor(context, [UIColor colorWithRed:.9 green:.3 blue:.3 alpha:1].CGColor);
107
108 CGContextSetLineDash(context, 0,partren , 2);
109 CGContextAddLines(context, points, 2);
110 //draw those defined after the last drawing
111 CGContextDrawPath(context, kCGPathStroke);
112
113 }
114
115 &
补充：移动开发 , IOS ,
