1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
|
/* Copyright (c) 2006-2013 by OpenLayers Contributors (see authors.txt for
* full list of contributors). Published under the 2-clause BSD license.
* See license.txt in the OpenLayers distribution or repository for the
* full text of the license. */
/**
* @requires OpenLayers/Strategy.js
*/
/**
* Class: OpenLayers.Strategy.Refresh
* A strategy that refreshes the layer. By default the strategy waits for a
* call to <refresh> before refreshing. By configuring the strategy with
* the <interval> option, refreshing can take place automatically.
*
* Inherits from:
* - <OpenLayers.Strategy>
*/
OpenLayers.Strategy.Refresh = OpenLayers.Class(OpenLayers.Strategy, {
/**
* Property: force
* {Boolean} Force a refresh on the layer. Default is false.
*/
force: false,
/**
* Property: interval
* {Number} Auto-refresh. Default is 0. If > 0, layer will be refreshed
* every N milliseconds.
*/
interval: 0,
/**
* Property: timer
* {Number} The id of the timer.
*/
timer: null,
/**
* Constructor: OpenLayers.Strategy.Refresh
* Create a new Refresh strategy.
*
* Parameters:
* options - {Object} Optional object whose properties will be set on the
* instance.
*/
/**
* APIMethod: activate
* Activate the strategy. Register any listeners, do appropriate setup.
*
* Returns:
* {Boolean} True if the strategy was successfully activated.
*/
activate: function() {
var activated = OpenLayers.Strategy.prototype.activate.call(this);
if(activated) {
if(this.layer.visibility === true) {
this.start();
}
this.layer.events.on({
"visibilitychanged": this.reset,
scope: this
});
}
return activated;
},
/**
* APIMethod: deactivate
* Deactivate the strategy. Unregister any listeners, do appropriate
* tear-down.
*
* Returns:
* {Boolean} True if the strategy was successfully deactivated.
*/
deactivate: function() {
var deactivated = OpenLayers.Strategy.prototype.deactivate.call(this);
if(deactivated) {
this.stop();
this.layer.events.un({
"visibilitychanged": this.reset,
scope: this
});
}
return deactivated;
},
/**
* Method: reset
* Start or cancel the refresh interval depending on the visibility of
* the layer.
*/
reset: function() {
if(this.layer.visibility === true) {
this.start();
} else {
this.stop();
}
},
/**
* Method: start
* Start the refresh interval.
*/
start: function() {
if(this.interval && typeof this.interval === "number" &&
this.interval > 0) {
this.timer = window.setInterval(
OpenLayers.Function.bind(this.refresh, this),
this.interval);
}
},
/**
* APIMethod: refresh
* Tell the strategy to refresh which will refresh the layer.
*/
refresh: function() {
if (this.layer && this.layer.refresh &&
typeof this.layer.refresh == "function") {
this.layer.refresh({force: this.force});
}
},
/**
* Method: stop
* Cancels the refresh interval.
*/
stop: function() {
if(this.timer !== null) {
window.clearInterval(this.timer);
this.timer = null;
}
},
CLASS_NAME: "OpenLayers.Strategy.Refresh"
});
|
