PieChart in iPhone

I was in need to include a pie chart view in my iPhone project to represent usage graphically. I first came up with a solution. That was to draw a circle of the full size and then drawing the angle that was calculated to the usage size i wanted to represent over the same circle with a different color. I did that into a simple drawRect function. Below are the codes i did.

float endDeg = [currentSize floatValue]/[maxSize floatValue];

NSLog(@"the end degree is : %f",endDeg);

endDeg = endDeg*360.00;

NSLog(@"the end degree is : %f",endDeg);

if(endDeg>360)

{

endDeg=360;

}

int x = 90;

int y = 80;

int r =70;

CGContextRef ctx=UIGraphicsGetCurrentContext();

CGContextSetRGBFillColor(ctx, 0, 255,0, 1.0);

CGContextMoveToPoint(ctx,x,y);//center point

CGContextAddArc(ctx,x,y,r,(0)*M_PI/180.0,(360)*M_PI/180.0,0);

CGContextFillPath(ctx);

CGContextSetRGBFillColor(ctx, 0,0,255, 0.9);

CGContextMoveToPoint(ctx,x,y);

CGContextAddArc(ctx,x,y,r,(0)*M_PI/180.0,(endDeg)*M_PI/180.0,0);

CGContextFillPath(ctx);

got the output but not the exact solution i needed. I Wanted some animation to that. Exploration ended in xyPieChart. I just simply integrated the class and customized it to what i needed and came up what i longed for. You can download the xyPieChart from here

There are hell out of frameworks open-sourced for graphical representation of data. 

I just included the xyPieChart classes to my project and the

In ViewDidLoad of the class where i needed to display the chart i included the following

Initiated the slice array which represents the number of slices in the Chart. And added the slice value to the array.

self.slices = [NSMutableArray arrayWithCapacity:2];

[_slices addObject:usedSize];

usedSize = [NSNumber numberWithInt:[maxSize intValue]-[usedSize intValue]];

[_slices addObject:usedSize];

[self.pieChartRight setDelegate:self];

[self.pieChartRight setDataSource:self];

[self.pieChartRight setPieCenter:CGPointMake(95,80)];

[self.pieChartRight setShowPercentage:YES];

self.pieChartRight.backgroundColor =[UIColor blackColor];

self.pieChartRight.layer.cornerRadius =10;

self.pieChartRight.layer.borderWidth = 1;

self.pieChartRight.layer.borderColor = [[UIColor colorWithRed:(188/255.f) green:230 blue:0 alpha:1.0] CGColor];

[self.percentageLabel.layer setCornerRadius:100];

self.sliceColors =[NSArray arrayWithObjects:

[UIColor colorWithRed:(0/255.f) green:0 blue:255 alpha:1.0],

// [UIColor colorWithRed:229/255.0 green:66/255.0 blue:115/255.0 alpha:1],

[UIColor colorWithRed:(0/255.f) green:255 blue:0 alpha:1.0],

and then i  included the follwing delegates.

//delegate for piechart

#pragma mark - XYPieChart Data Source

- (NSUInteger)numberOfSlicesInPieChart:(XYPieChart *)pieChart

{

return self.slices.count;

}

- (CGFloat)pieChart:(XYPieChart *)pieChart valueForSliceAtIndex:(NSUInteger)index

{

return [[self.slices objectAtIndex:index] intValue];

}

- (UIColor *)pieChart:(XYPieChart *)pieChart colorForSliceAtIndex:(NSUInteger)index

{

return [self.sliceColors objectAtIndex:index];

}

#pragma mark - XYPieChart Delegate

- (void)pieChart:(XYPieChart *)pieChart didSelectSliceAtIndex:(NSUInteger)index

{

NSLog(@"did select slice at index %d",index);

self.selectedSliceLabel.text = [NSString stringWithFormat:@"$%@",[self.slices objectAtIndex:index]];

}

Thats it i got the chart displayed well on my page animated.