Customize the color and size of the page control

Hello Friends,

Today we will go for the customize page control. Page control is the functionality is used with scrolling photos. Apple has given UIPageControl for the paging implementation. But that is not customizable in delegate method. It does not contain property variables for the variations. Every time it does not fit in the project. As the project sometimes contain white color background, at that time page control does not appear on the view.

For making customize page control follow the following steps.

To use below code in the your project. Put following code in you project.
 

CGRect f = CGRectMake(0, 0, 320, 20); 
PageControl *pageControl = [[[PageControl alloc] initWithFrame:f] autorelease];
pageControl.numberOfPages = 10;
pageControl.currentPage = 5;
pageControl.delegate = self;
[self addSubview:pageControl];

Now Add the following files in your project.

Header File:
Import

//  Created by Morten Heiberg  on November 1, 2010.
//

@protocol PageControlDelegate;

@interface PageControl : UIView 
{
@private
    NSInteger _currentPage;
    NSInteger _numberOfPages;
    UIColor *dotColorCurrentPage;
    UIColor *dotColorOtherPage;
    NSObject *delegate;
}

// Set these to control the PageControl.
@property (nonatomic) NSInteger currentPage;
@property (nonatomic) NSInteger numberOfPages;

// Customize these as well as the backgroundColor property.
@property (nonatomic, retain) UIColor *dotColorCurrentPage;
@property (nonatomic, retain) UIColor *dotColorOtherPage;

// Optional delegate for callbacks when user taps a page dot.
@property (nonatomic, assign) NSObject *delegate;

@end

@protocol PageControlDelegate
@optional
- (void)pageControlPageDidChange:(PageControl *)pageControl;
@end

Implementation file:

//
//  PageControl.m
//
//  Replacement for UIPageControl because that one only supports white dots.
//
//  Created by Morten Heiberg  on November 1, 2010.
//

#import "PageControl.h"

// Tweak these or make them dynamic.
#define kDotDiameter 7.0
#define kDotSpacer 7.0

@implementation PageControl

@synthesize dotColorCurrentPage;
@synthesize dotColorOtherPage;
@synthesize delegate;

- (NSInteger)currentPage
{
    return _currentPage;
}

- (void)setCurrentPage:(NSInteger)page
{
    _currentPage = MIN(MAX(0, page), _numberOfPages-1);
    [self setNeedsDisplay];
}

- (NSInteger)numberOfPages
{
    return _numberOfPages;
}

- (void)setNumberOfPages:(NSInteger)pages
{
    _numberOfPages = MAX(0, pages);
    _currentPage = MIN(MAX(0, _currentPage), _numberOfPages-1);
    [self setNeedsDisplay];
}

- (id)initWithFrame:(CGRect)frame 
{
    if ((self = [super initWithFrame:frame])) 
    {
        // Default colors.
        self.backgroundColor = [UIColor clearColor];
        self.dotColorCurrentPage = [UIColor blackColor];
        self.dotColorOtherPage = [UIColor lightGrayColor];
    }
    return self;
}

- (void)drawRect:(CGRect)rect 
{
    CGContextRef context = UIGraphicsGetCurrentContext();   
    CGContextSetAllowsAntialiasing(context, true);

    CGRect currentBounds = self.bounds;
    CGFloat dotsWidth = self.numberOfPages*kDotDiameter + MAX(0, self.numberOfPages-1)*kDotSpacer;
    CGFloat x = CGRectGetMidX(currentBounds)-dotsWidth/2;
    CGFloat y = CGRectGetMidY(currentBounds)-kDotDiameter/2;
    for (int i=0; i<_numberOfPages; i++)
    {
        CGRect circleRect = CGRectMake(x, y, kDotDiameter, kDotDiameter);
        if (i == _currentPage)
        {
            CGContextSetFillColorWithColor(context, self.dotColorCurrentPage.CGColor);
        }
        else
        {
            CGContextSetFillColorWithColor(context, self.dotColorOtherPage.CGColor);
        }
        CGContextFillEllipseInRect(context, circleRect);
        x += kDotDiameter + kDotSpacer;
    }
}

- (void)dealloc 
{
    [dotColorCurrentPage release];
    [dotColorOtherPage release];
    [super dealloc];
}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    if (!self.delegate) return;

    CGPoint touchPoint = [[[event touchesForView:self] anyObject] locationInView:self];

    CGFloat dotSpanX = self.numberOfPages*(kDotDiameter + kDotSpacer);
    CGFloat dotSpanY = kDotDiameter + kDotSpacer;

    CGRect currentBounds = self.bounds;
    CGFloat x = touchPoint.x + dotSpanX/2 - CGRectGetMidX(currentBounds);
    CGFloat y = touchPoint.y + dotSpanY/2 - CGRectGetMidY(currentBounds);

    if ((x<0) || (x>dotSpanX) || (y<0) || (y>dotSpanY)) return;

    self.currentPage = floor(x/(kDotDiameter+kDotSpacer));
    if ([self.delegate respondsToSelector:@selector(pageControlPageDidChange:)])
    {
        [self.delegate pageControlPageDidChange:self];
    }
}

@end

Enjoy... :-)