Beginning Core graphics on the iPhone

• (4.0)

• | 770 Ratings |

• Last Updated March 07, 2017

Core Graphics FrameWork Reference:

The Core Graphics Framework is a c-based API that is based on the quartz advanced drawing engine. It provides low-level light 20 rendering with unmatched output fidelity. You use this framework to handle path–based drawing, transformation, color management,  off screen rendering, patterns, gradients and shadings, image data  management, Image Creation masking and POF document creation, display and parsing.

Structures:-

a) CGpoint
b) CGRect
c) CGSize

A) Struct   CGpoint
     {
       CGFloat   x;
       CGFloat   y;
      }
b) struct    CGRect
    {
       CGRect
       CGpoint    Origin;
       CGSize      Size;
    }
c) struct CGSize
    {
      CGFloat width;
      CGFloat  height;
    }

// preparing CGPoint:   (x,y)

CGPoint    pnt;   <img alt="" src="https://mindmajix.com/blogs/images/Screenshot_1819.png" style="height:20px; width:24px" />object   creating   for   CG point
  Pnt .x     =    200;
  Pnt .y     =    50;
           (or)
CGPoint  make   (200,50);

// preparing     CGSize  :     ( width ,   height)

CG size     Size;
Size.    Width     =200;
Size.    Height    =  100;
         (or)
CGSizeMake  (  200,100);
// preparing CGRect   (x,y,  width, height)

CGRect  re;

rc. Origin .x=20;
rc. origin .y=30;

rc. Size. Width= 100;
rc. size. height=200;
(or)
CGRectMake  (20,30,100,200);

Bounds:-

. h file:-

#  import    
@  interface   UI titledViewController   :   UIViewController
{
IBOutlet     UIImage   view*  imgview;
}
-(IBAction )  button   click;
@  end

  . m file:-

#  import   “ UItitledViewController. h”
@  implementation   UItitledViewController
-(void) viewDidload
 {
  Imgview.  Image   =  [UIImage  imageNamed@  “I phone – 4.jpg”]
  Imgview .frame   =    self  .  view   . frame;
 Imgview . alpha  = 1;
[  Super viewDidload];
}
-(IBAction )   button   click
 {
CGRect    rc   =  imgview. Frame;
NSLog   (@  “rc  is    c  %     0. Of,   %  0.of,  %0.of”);
rc .origin  x ,rc. Origin .y,          rc. size. width ,rc size. Height);
                                                       ↓           ↓  
        Point origin             +         point   size  =   CGRect

// Imgview. frame=  CGRectMake  (rc.origin.x+100,
(To make changes                 rc.origin.y+150,                          
    In the image                 rc.size.width+50;
Which is in the Rect )           rc .size. height+50);
// center
Imgview .Center    = self .view .center;
Img view.  bounds

 

Frequently Asked IPhone Interview Questions & Answers