MTImageMapView

An UIImageView subclass to select a complex polygon map out of many
Extremely useful for handling touches on, for example, Europe map, or an eye of owl

Screen Shots

Features

• Handling multiple maps on an image¹
• Multiple MTImageMapView on a single view
• Support Interface Builder, or progmatical initiation
• Batch mapping²
• Completion block for notifying the end of mapping³
• Delegate to provide selected map index
• Single public class and protocol to implement
• Debug mode to superimpose maps on an image

1. There is no limit but you need to be reasonable. In this example, I put around 50.
2. Mapping takes place in background and prevents UI animation from stuttering.
3. At the end, mapping function notifies on main thread.

Support

• XCode 4.4 or higher required
• Works on iOS 4.3 ~ iOS 6.0 ARC/MRC (tested on devices)
• Starting from iOS 6.0, DispatchObjects are Object-C objects, meaning when you are to go with ARC, DispatchObjects are also managed by ARC.
  ♠ You can read more detail at Does ARC support dispatch queues?.
  ♦ This paricular issue is solved with OS_OBJECT_USE_OBJC flag. You can read more in detail at OMG, GCD+ARC.

Implementation

1. Use tools like Gimp and generate a image map.
2. Copy only coordinate pairs of the map (e.g. "123,242,452,242,142,322") in NSString type.
3. Put the strings in an NSArray.
4. Instantiate MTImageMapView and implement MTImageMapDelegate procotol.
5. pass the array to the map view.
   (You can use .plist to pass a map batch to a MTImageMapView.)

    MTImageMapView *viewImageMap =\
        [[MTImageMapView alloc]
         initWithImage:
            [UIImage imageNamed:@"sample_image.png"]
         ];

    [viewImageMap setDelegate:self];
    [self.view addSubview:viewImageMap];
    
    NSArray *arrStates = \
        [NSArray arrayWithObjects:
         @"542,94,568,94,568,111,542,111"
         @"555,150,574,150,574,161,555,161"
         @"535,149,551,149,551,159,535,159"
         ,nil];

    [viewImageMap
     setMapping:arrStates
     doneBlock:^(MTImageMapView *imageMapView) {
         NSLog(@"Mapping complete!");
     }];

	-(void)imageMapView:(MTImageMapView *)inImageMapView
	   didSelectMapArea:(NSUInteger)inIndexSelected
	    areaCentrePoint:(CGPoint)point
	{
	    [[[[UIAlertView alloc]
	     initWithTitle:@"*** State Name ***"
	     message:[stateNames objectAtIndex:inIndexSelected]
	     delegate:nil
	     cancelButtonTitle:@"Ok"
	     otherButtonTitles:nil]
	      autorelease] show];
	}

LIMITS

• Delegate only receives the index of a map
• Coordinates must be provided in pairs
• At least 3 pairs of coordinates must be presented
• No "rect", "circle" type map is supported. "Polygon" only at this time being

Credits

• US states image and all coordinates are credited to Illinois Center for Information Technology and Web Accessibility
• The center point of a selected area by @RajnishTomar

License

BSD license follows (http://www.opensource.org/licenses/bsd-license.php)

Copyright © 2012-2022 Sung-Taek, Kim All Rights Reserved.

Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:

Redistributions of  source code  must retain  the above  copyright notice,
this list of  conditions and the following  disclaimer. Redistributions in
binary  form must  reproduce  the  above copyright  notice,  this list  of
conditions and the following disclaimer  in the documentation and/or other
materials  provided with  the distribution.  Neither the  name of  Sung-Ta
ek kim nor the names of its contributors may be used to endorse or promote
products  derived  from  this  software  without  specific  prior  written
permission.  THIS  SOFTWARE  IS  PROVIDED BY  THE  COPYRIGHT  HOLDERS  AND
CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT
NOT LIMITED TO, THE IMPLIED  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A  PARTICULAR PURPOSE  ARE DISCLAIMED.  IN  NO EVENT  SHALL THE  COPYRIGHT
HOLDER OR  CONTRIBUTORS BE  LIABLE FOR  ANY DIRECT,  INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY,  OR CONSEQUENTIAL DAMAGES (INCLUDING,  BUT NOT LIMITED
TO, PROCUREMENT  OF SUBSTITUTE GOODS  OR SERVICES;  LOSS OF USE,  DATA, OR
PROFITS; OR  BUSINESS INTERRUPTION)  HOWEVER CAUSED AND  ON ANY  THEORY OF
LIABILITY,  WHETHER  IN CONTRACT,  STRICT  LIABILITY,  OR TORT  (INCLUDING
NEGLIGENCE  OR OTHERWISE)  ARISING  IN ANY  WAY  OUT OF  THE  USE OF  THIS
SOFTWARE,   EVEN  IF   ADVISED  OF   THE  POSSIBILITY   OF  SUCH   DAMAGE.

VER : 1.1

UPDATED : Nov. 11, 2022