先上图(做出来的效果就是下图的样子)
1.效果图-w220
图中不论每个扇形多小,都可以从指引线处将指引的数据分割开来,不会重叠。
需要给图中数据做个模型
@interface DVFoodPieModel : NSObject /** 名称 */ @property (copy, nonatomic) NSString *name; /** 数值 */ @property (assign, nonatomic) CGFloat value; /** 比例 */ @property (assign, nonatomic) CGFloat rate; @end
现在先把饼图中间的圆形做出来,这个没有什么难度,直接贴代码
在.h文件中
@interface DVPieCenterView : UIView @property (strong, nonatomic) UILabel *nameLabel; @end
在.m文件中
@interface DVPieCenterView () @property (strong, nonatomic) UIView *centerView; @end @implementation DVPieCenterView - (instancetype)initWithFrame:(CGRect)frame { if (self = [super initWithFrame:frame]) { self.backgroundColor = [[UIColor whiteColor] colorWithAlphaComponent:0.4]; UIView *centerView = [[UIView alloc] init]; centerView.backgroundColor = [UIColor whiteColor]; [self addSubview:centerView]; self.centerView = centerView; UILabel *nameLabel = [[UILabel alloc] init]; nameLabel.textColor = [UIColor colorWithRed:51/255.0 green:51/255.0 blue:51/255.0 alpha:1]; nameLabel.font = [UIFont systemFontOfSize:18]; nameLabel.textAlignment = NSTextAlignmentCenter; self.nameLabel = nameLabel; [centerView addSubview:nameLabel]; } return self; } - (void)layoutSubviews { [super layoutSubviews]; self.layer.cornerRadius = self.frame.size.width * 0.5; self.layer.masksToBounds = true; self.centerView.frame = CGRectMake(6, 6, self.frame.size.width - 6 * 2, self.frame.size.height - 6 * 2); self.centerView.layer.cornerRadius = self.centerView.frame.size.width * 0.5; self.centerView.layer.masksToBounds = true; self.nameLabel.frame = self.centerView.bounds; }
暴露的只有.h文件中的namelabel,需要中间显示文字时,给nameLabel的text赋值就好了
现在就创建一个继承UIView的视图,用来画饼状图和指引线以及数据
在.h文件中需要有数据数组,还有中间显示的文字,以及一个draw方法(draw方法纯属个人习惯,在数据全部赋值完成后,调用该方法进行绘画)
@interface DVPieChart : UIView /** 数据数组 */ @property (strong, nonatomic) NSArray *dataArray; /** 标题 */ @property (copy, nonatomic) NSString *title; /** 绘制方法 */ - (void)draw; @end
在调用draw方法前应确定数据全部赋值完成,绘制工作其实是在- (void)drawRect:(CGRect)rect方法中完成的,所以.h文件中的draw方法只是来调用系统方法的
在.m文件中, draw 方法的实现
- (void)draw { [self.subviews makeObjectsPerformSelector:@selector(removeFromSuperview)]; [self setNeedsDisplay]; }
[self setNeedsDisplay];就是来调用drawRect方法的
[self.subviews makeObjectsPerformSelector:@selector(removeFromSuperview)];这个方法是用来移除添加到pieChart上的centerView,不然每次重绘时都会再次添加一个centerView
下面就是 drawRect 方法的实现
首先需要确定圆的半径,中心点和起始点
CGFloat min = self.bounds.size.width > self.bounds.size.height ? self.bounds.size.height : self.bounds.size.width; CGPoint center = CGPointMake(self.bounds.size.width * 0.5, self.bounds.size.height * 0.5); CGFloat radius = min * 0.5 - CHART_MARGIN; CGFloat start = 0; CGFloat angle = 0; CGFloat end = start;
CHART_MARGIN是自己定义的一个宏,圆不能让视图的边形成切线,在此我把CHART_MARGIN设定为60
* 根据产品的需求,当请求回来的数据为空时,显示一个纯色的圆,不画指引线,所以在drawRect中分两种情况来实现 ```objc if (self.dataArray.count == 0) { } else { } ``` * 当dataArray的长度为0时 ```objc if (self.dataArray.count == 0) { end = start + M_PI * 2; UIColor *color = COLOR_ARRAY.firstObject; UIBezierPath *path = [UIBezierPath bezierPathWithArcCenter:center radius:radius startAngle:start endAngle:end clockwise:true]; [color set]; //添加一根线到圆心 [path addLineToPoint:center]; [path fill]; } ``` > COLOR_ARRAY是自己设定的一个宏定义,产品要求的饼图份数是6份,每份颜色一定,所以做一个宏定义存储一下(做成变量都是可以的,看自己代码风格) ``` objc #define COLOR_ARRAY @[/
[UIColor colorWithRed:251/255.0 green:166.9/255.0 blue:96.5/255.0 alpha:1],
[UIColor colorWithRed:151.9/255.0 green:188/255.0 blue:95.8/255.0 alpha:1],
[UIColor colorWithRed:245/255.0 green:94/255.0 blue:102/255.0 alpha:1],
[UIColor colorWithRed:29/255.0 green:140/255.0 blue:140/255.0 alpha:1],
[UIColor colorWithRed:121/255.0 green:113/255.0 blue:199/255.0 alpha:1],
[UIColor colorWithRed:16/255.0 green:149/255.0 blue:224/255.0 alpha:1]
]
```
* 当dataArray的长度不为0时
``objc for (int i = 0; i < self.dataArray.count; i++) { DVFoodPieModel *model = self.dataArray[i]; CGFloat percent = model.rate; UIColor *color = COLOR_ARRAY[i % 6]; start = end; angle = percent * M_PI * 2; end = start + angle; UIBezierPath *path = [UIBezierPath bezierPathWithArcCenter:center radius:radius startAngle:start endAngle:end clockwise:true]; [color set]; //添加一根线到圆心 [path addLineToPoint:center]; [path fill]; } ```
在else中这么做,就能绘制出各个扇形
* 在扇形绘画出来后,添加centerView ```objc // 在中心添加label DVPieCenterView *centerView = [[DVPieCenterView alloc] init]; centerView.frame = CGRectMake(0, 0, 80, 80); CGRect frame = centerView.frame; frame.origin = CGPointMake(self.frame.size.width * 0.5 - frame.size.width * 0.5, self.frame.size.height * 0.5 - frame.size.width * 0.5); centerView.frame = frame; centerView.nameLabel.text = self.title; [self addSubview:centerView]; ```
绘制指引线,需要在画扇形时就确定几个数据,并根据这几种数据进行绘制
各个扇形圆弧的中心点
指引线的重点(效果图中有圆点的位置)
// 获取弧度的中心角度 CGFloat radianCenter = (start + end) * 0.5; // 获取指引线的终点 CGFloat lineStartX = self.frame.size.width * 0.5 + radius * cos(radianCenter); CGFloat lineStartY = self.frame.size.height * 0.5 + radius * sin(radianCenter); CGPoint point = CGPointMake(lineStartX, lineStartY);
因为这个图刚刚做出来时是有重叠的,按产品需求进行更改,所以起的变量名称会有些歧义,不方便改了,我只能做好注释,大家以注释为准
如果按顺序进行绘制的话,那么很难让指引线的位置不重叠,所以从中间的一个数据先进行绘制,然后在绘制中间数据两侧的数据
那么,现在需要将上面需要确定的数据依次添加到一个数组中
例:原数据为@[@1, @2, @3, @4, @5, @6]
画指引线时则需要数据这样来弄@[@3, @2, @1, @4, @5, @6]
所以for循环中应该改成这个样子
注意,数据变更顺序了之后,绘制时模型数据和颜色数据也需要变更顺序
首先声明两个变量
@interface DVPieChart () @property (nonatomic, strong) NSMutableArray *modelArray; @property (nonatomic, strong) NSMutableArray *colorArray; @end
else中变成下面这个样子
NSMutableArray *pointArray = [NSMutableArray array]; NSMutableArray *centerArray = [NSMutableArray array]; self.modelArray = [NSMutableArray array]; self.colorArray = [NSMutableArray array]; for (int i = 0; i < self.dataArray.count; i++) { DVFoodPieModel *model = self.dataArray[i]; CGFloat percent = model.rate; UIColor *color = COLOR_ARRAY[i]; start = end; angle = percent * M_PI * 2; end = start + angle; UIBezierPath *path = [UIBezierPath bezierPathWithArcCenter:center radius:radius startAngle:start endAngle:end clockwise:true]; [color set]; //添加一根线到圆心 [path addLineToPoint:center]; [path fill]; // 获取弧度的中心角度 CGFloat radianCenter = (start + end) * 0.5; // 获取指引线的终点 CGFloat lineStartX = self.frame.size.width * 0.5 + radius * cos(radianCenter); CGFloat lineStartY = self.frame.size.height * 0.5 + radius * sin(radianCenter); CGPoint point = CGPointMake(lineStartX, lineStartY); if (i <= self.dataArray.count / 2 - 1) { [pointArray insertObject:[NSValue valueWithCGPoint:point] atIndex:0]; [centerArray insertObject:[NSNumber numberWithFloat:radianCenter] atIndex:0]; [self.modelArray insertObject:model atIndex:0]; [self.colorArray insertObject:color atIndex:0]; } else { [pointArray addObject:[NSValue valueWithCGPoint:point]]; [centerArray addObject:[NSNumber numberWithFloat:radianCenter]]; [self.modelArray addObject:model]; [self.colorArray addObject:color]; } }
for循环中确定了需要的数据:
pointArray、centerArray、self.modelArray、self.colorArray
根据上面确定的数据来绘出指引线,逻辑比较复杂,写一个方法来绘制
- (void)drawLineWithPointArray:(NSArray *)pointArray centerArray:(NSArray *)centerArray
在for循环外调用
// 通过pointArray和centerArray绘制指引线 [self drawLineWithPointArray:pointArray centerArray:centerArray];
方法内部实现
需要确定的数据都有:
1.指引线长度
2.指引线起点、终点、转折点
3.指引线数据所占的rect范围(用于确定绘制下一个的时候是否有重叠)
下面直接贴出代码实现, 注意看注释 ,我就不在代码外再写一遍了
- (void)drawLineWithPointArray:(NSArray *)pointArray centerArray:(NSArray *)centerArray { // 记录每一个指引线包括数据所占用位置的和(总体位置) CGRect rect = CGRectZero; // 用于计算指引线长度 CGFloat width = self.bounds.size.width * 0.5; for (int i = 0; i < pointArray.count; i++) { // 取出数据 NSValue *value = pointArray[i]; // 每个圆弧中心店的位置 CGPoint point = value.CGPointValue; // 每个圆弧中心点的角度 CGFloat radianCenter = [centerArray[i] floatValue]; // 颜色(绘制数据时要用) UIColor *color = self.colorArray[i % 6]; // 模型数据(绘制数据时要用) DVFoodPieModel *model = self.modelArray[i]; // 模型的数据 NSString *name = model.name; NSString *number = [NSString stringWithFormat:@"%.2f%%", model.rate * 100]; // 圆弧中心点的x值和y值 CGFloat x = point.x; CGFloat y = point.y; // 指引线终点的位置(x, y) CGFloat startX = x + 10 * cos(radianCenter); CGFloat startY = y + 10 * sin(radianCenter); // 指引线转折点的位置(x, y) CGFloat breakPointX = x + 20 * cos(radianCenter); CGFloat breakPointY = y + 20 * sin(radianCenter); // 转折点到中心竖线的垂直长度(为什么+20, 在实际做出的效果中,有的转折线很丑,+20为了美化) CGFloat margin = fabs(width - breakPointX) + 20; // 指引线长度 CGFloat lineWidth = width - margin; // 指引线起点(x, y) CGFloat endX; CGFloat endY; // 绘制文字和数字时,所占的size(width和height) // width使用lineWidth更好,我这么写固定值是为了达到产品要求 CGFloat numberWidth = 80.f; CGFloat numberHeight = 15.f; CGFloat titleWidth = numberWidth; CGFloat titleHeight = numberHeight; // 绘制文字和数字时的起始位置(x, y)与上面的合并起来就是frame CGFloat numberX;// = breakPointX; CGFloat numberY = breakPointY - numberHeight; CGFloat titleX = breakPointX; CGFloat titleY = breakPointY + 2; // 文本段落属性(绘制文字和数字时需要) NSMutableParagraphStyle * paragraph = [[NSMutableParagraphStyle alloc]init]; // 文字靠右 paragraph.alignment = NSTextAlignmentRight; // 判断x位置,确定在指引线向左还是向右绘制 // 根据需要变更指引线的起始位置 // 变更文字和数字的位置 if (x <= width) { // 在左边 endX = 10; endY = breakPointY; // 文字靠左 paragraph.alignment = NSTextAlignmentLeft; numberX = endX; titleX = endX; } else { // 在右边 endX = self.bounds.size.width - 10; endY = breakPointY; numberX = endX - numberWidth; titleX = endX - titleWidth; } if (i != 0) { // 当i!=0时,就需要计算位置总和(方法开始出的rect)与rect1(将进行绘制的位置)是否有重叠 CGRect rect1 = CGRectMake(numberX, numberY, numberWidth, titleY + titleHeight - numberY); CGFloat margin = 0; if (CGRectIntersectsRect(rect, rect1)) { // 两个面积重叠 // 三种情况 // 1. 压上面 // 2. 压下面 // 3. 包含 // 通过计算让面积重叠的情况消除 if (CGRectContainsRect(rect, rect1)) {// 包含 if (i % self.dataArray.count rect.origin.y && rect1.origin.y < rect.origin.y) { // 压在总位置上面 margin = CGRectGetMaxY(rect1) - rect.origin.y; endY -= margin; } else if (rect1.origin.y < CGRectGetMaxY(rect) && CGRectGetMaxY(rect1) > CGRectGetMaxY(rect)) { // 压总位置下面 margin = CGRectGetMaxY(rect) - rect1.origin.y; endY += margin; } } } titleY = endY + 2; numberY = endY - numberHeight; // 通过计算得出的将要绘制的位置 CGRect rect2 = CGRectMake(numberX, numberY, numberWidth, titleY + titleHeight - numberY); // 把新获得的rect和之前的rect合并 if (numberX == rect.origin.x) { // 当两个位置在同一侧的时候才需要合并 if (rect2.origin.y < rect.origin.y) { rect = CGRectMake(rect.origin.x, rect2.origin.y, rect.size.width, rect.size.height + rect2.size.height); } else { rect = CGRectMake(rect.origin.x, rect.origin.y, rect.size.width, rect.size.height + rect2.size.height); } } } else { rect = CGRectMake(numberX, numberY, numberWidth, titleY + titleHeight - numberY); } // 重新制定转折点 if (endX == 10) { breakPointX = endX + lineWidth; } else { breakPointX = endX - lineWidth; } breakPointY = endY; //1.获取上下文 CGContextRef ctx = UIGraphicsGetCurrentContext(); //2.绘制路径 UIBezierPath *path = [UIBezierPath bezierPath]; [path moveToPoint:CGPointMake(endX, endY)]; [path addLineToPoint:CGPointMake(breakPointX, breakPointY)]; [path addLineToPoint:CGPointMake(startX, startY)]; CGContextSetLineWidth(ctx, 0.5); //设置颜色 [color set]; //3.把绘制的内容添加到上下文当中 CGContextAddPath(ctx, path.CGPath); //4.把上下文的内容显示到View上(渲染到View的layer)(stroke fill) CGContextStrokePath(ctx); // 在终点处添加点(小圆点) // movePoint,让转折线指向小圆点中心 CGFloat movePoint = -2.5; UIView *view = [[UIView alloc] init]; view.backgroundColor = color; [self addSubview:view]; CGRect rect = view.frame; rect.size = CGSizeMake(5, 5); rect.origin = CGPointMake(startX + movePoint, startY - 2.5); view.frame = rect; view.layer.cornerRadius = 2.5; view.layer.masksToBounds = true; //指引线上面的数字 [name drawInRect:CGRectMake(numberX, numberY, numberWidth, numberHeight) withAttributes:@{NSFontAttributeName:[UIFont systemFontOfSize:9.0], NSForegroundColorAttributeName:color,NSParagraphStyleAttributeName:paragraph}]; // 指引线下面的title [number drawInRect:CGRectMake(titleX, titleY, titleWidth, titleHeight) withAttributes:@{NSFontAttributeName:[UIFont systemFontOfSize:9.0],NSForegroundColorAttributeName:color,NSParagraphStyleAttributeName:paragraph}]; } }
附 github地址 : https://github.com/FireMou/DVPieChart
作者:Fire_day
链接:https://www.jianshu.com/p/bc9029c32fc1