1 | /* Copyright (c) 2006-2010 by OpenLayers Contributors (see authors.txt for |
---|
2 | * full list of contributors). Published under the Clear BSD license. |
---|
3 | * See http://svn.openlayers.org/trunk/openlayers/license.txt for the |
---|
4 | * full text of the license. */ |
---|
5 | |
---|
6 | /** |
---|
7 | * Constructor: OpenLayers.Class |
---|
8 | * Base class used to construct all other classes. Includes support for |
---|
9 | * multiple inheritance. |
---|
10 | * |
---|
11 | * This constructor is new in OpenLayers 2.5. At OpenLayers 3.0, the old |
---|
12 | * syntax for creating classes and dealing with inheritance |
---|
13 | * will be removed. |
---|
14 | * |
---|
15 | * To create a new OpenLayers-style class, use the following syntax: |
---|
16 | * > var MyClass = OpenLayers.Class(prototype); |
---|
17 | * |
---|
18 | * To create a new OpenLayers-style class with multiple inheritance, use the |
---|
19 | * following syntax: |
---|
20 | * > var MyClass = OpenLayers.Class(Class1, Class2, prototype); |
---|
21 | * Note that instanceof reflection will only reveil Class1 as superclass. |
---|
22 | * Class2 ff are mixins. |
---|
23 | * |
---|
24 | */ |
---|
25 | OpenLayers.Class = function() { |
---|
26 | var Class = function() { |
---|
27 | /** |
---|
28 | * This following condition can be removed at 3.0 - this is only for |
---|
29 | * backwards compatibility while the Class.inherit method is still |
---|
30 | * in use. So at 3.0, the following three lines would be replaced with |
---|
31 | * simply: |
---|
32 | * this.initialize.apply(this, arguments); |
---|
33 | */ |
---|
34 | if (arguments && arguments[0] != OpenLayers.Class.isPrototype) { |
---|
35 | this.initialize.apply(this, arguments); |
---|
36 | } |
---|
37 | }; |
---|
38 | var extended = {}; |
---|
39 | var parent, initialize, Type; |
---|
40 | for(var i=0, len=arguments.length; i<len; ++i) { |
---|
41 | Type = arguments[i]; |
---|
42 | if(typeof Type == "function") { |
---|
43 | // make the class passed as the first argument the superclass |
---|
44 | if(i == 0 && len > 1) { |
---|
45 | initialize = Type.prototype.initialize; |
---|
46 | // replace the initialize method with an empty function, |
---|
47 | // because we do not want to create a real instance here |
---|
48 | Type.prototype.initialize = function() {}; |
---|
49 | // the line below makes sure that the new class has a |
---|
50 | // superclass |
---|
51 | extended = new Type(); |
---|
52 | // restore the original initialize method |
---|
53 | if(initialize === undefined) { |
---|
54 | delete Type.prototype.initialize; |
---|
55 | } else { |
---|
56 | Type.prototype.initialize = initialize; |
---|
57 | } |
---|
58 | } |
---|
59 | // get the prototype of the superclass |
---|
60 | parent = Type.prototype; |
---|
61 | } else { |
---|
62 | // in this case we're extending with the prototype |
---|
63 | parent = Type; |
---|
64 | } |
---|
65 | OpenLayers.Util.extend(extended, parent); |
---|
66 | } |
---|
67 | Class.prototype = extended; |
---|
68 | return Class; |
---|
69 | }; |
---|
70 | |
---|
71 | /** |
---|
72 | * Property: isPrototype |
---|
73 | * *Deprecated*. This is no longer needed and will be removed at 3.0. |
---|
74 | */ |
---|
75 | OpenLayers.Class.isPrototype = function () {}; |
---|
76 | |
---|
77 | /** |
---|
78 | * APIFunction: OpenLayers.create |
---|
79 | * *Deprecated*. Old method to create an OpenLayers style class. Use the |
---|
80 | * <OpenLayers.Class> constructor instead. |
---|
81 | * |
---|
82 | * Returns: |
---|
83 | * An OpenLayers class |
---|
84 | */ |
---|
85 | OpenLayers.Class.create = function() { |
---|
86 | return function() { |
---|
87 | if (arguments && arguments[0] != OpenLayers.Class.isPrototype) { |
---|
88 | this.initialize.apply(this, arguments); |
---|
89 | } |
---|
90 | }; |
---|
91 | }; |
---|
92 | |
---|
93 | |
---|
94 | /** |
---|
95 | * APIFunction: inherit |
---|
96 | * *Deprecated*. Old method to inherit from one or more OpenLayers style |
---|
97 | * classes. Use the <OpenLayers.Class> constructor instead. |
---|
98 | * |
---|
99 | * Parameters: |
---|
100 | * class - One or more classes can be provided as arguments |
---|
101 | * |
---|
102 | * Returns: |
---|
103 | * An object prototype |
---|
104 | */ |
---|
105 | OpenLayers.Class.inherit = function () { |
---|
106 | var superClass = arguments[0]; |
---|
107 | var proto = new superClass(OpenLayers.Class.isPrototype); |
---|
108 | for (var i=1, len=arguments.length; i<len; i++) { |
---|
109 | if (typeof arguments[i] == "function") { |
---|
110 | var mixin = arguments[i]; |
---|
111 | arguments[i] = new mixin(OpenLayers.Class.isPrototype); |
---|
112 | } |
---|
113 | OpenLayers.Util.extend(proto, arguments[i]); |
---|
114 | } |
---|
115 | return proto; |
---|
116 | }; |
---|