For IOS, the simple code for creating a pie chart is annotated. for ios

For IOS, the simple code for creating a pie chart is annotated. for ios

Today we bring you the implementation of the pie chart in IOS graphics

. H file

# Import <UIKit/UIKit. h>

 

@ Interface ZXCircle: UIView

 

@ End

. M file

# Import "ZXCircle. h"

 

@ Implementation ZXCircle

-(Void) drawRect :( CGRect) rect {

CGFloat w = self. bounds. size. width;

CGFloat h = self. bounds. size. height;

// Data array

NSArray * array = @ [@ 1, @ 2, @ 3, @ 4, @ 5, @ 6, @ 7, @ 8, @ 9, @ 10];

// Color array

NSArray * colorArray = @ [[UIColor redColor], [UIColor greenColor], [UIColor yellowColor], [UIColor cyanColor], [UIColor blueColor], [UIColor lightGrayColor], [UIColor grayColor], [UIColor darkGrayColor], [UIColor magentaColor], [UIColor orangeColor];

// The following loop uses the color Algorithm in the case of only several colors but a large amount of data.

// New color array

NSMutableArray * colorArr = [NSMutableArray new];

// This loop shows only the first three colors in the color array. % The number following is based on the number of colors in your color array.

For (int I = 0; I <array. count; I ++ ){

[ColorArr addObject: colorArray [I % 10];

}

CGContextRef ctx = UIGraphicsGetCurrentContext ();

// Center point

CGPoint center = CGPointMake (w * 0.5, h * 0.5 );

// Radius

CGFloat radius = w * 0.3-5;

// Start point

CGFloat startA = 0;

// End point angle

CGFloat endA = M_PI;

// Scan the angle range

CGFloat angle = 0;

For (int I = 0; I <array. count; I ++ ){

// This sentence is used to draw one of them, and the second start point is the first end point. M_PI indicates that the value 180 degrees 55 is the sum of the data sources.

StartA = endA;

Angle = [array [I] integerValue]/55 * M_PI * 2;

EndA = startA + angle;

// Arc path

// Clockwise: whether it is rotated in the clock direction (clockwise or not)

UIBezierPath * path = [UIBezierPath bezierPathWithArcCenter: center radius: radius startAngle: startA endAngle: endA clockwise: YES];

// Connection center, forming a fan

[Path addLineToPoint: center];

// Fill color

[(UIColor *) colorArr [I] set];

CGContextAddPath (ctx, path. CGPath );

// Render the context to the view

CGContextFillPath (ctx );

}

}

@ End

The following is a simple pie chart. I hope it will be helpful for your future development !! Thank you !!