openlayers/lib/OpenLayers/Control/Pan.js

   1 /* Copyright (c) 2006-2008 MetaCarta, Inc., published under the Clear BSD
   2  * license.  See http://svn.openlayers.org/trunk/openlayers/license.txt for the
   3  * full text of the license. */
   4
   5 /**
   6  * @requires OpenLayers/Control.js
   7  */
   8
   9 /**
  10  * Class: OpenLayers.Control.Pan
  11  * The Pan control is a single button to pan the map in one direction. For
  12  * a more complete control see <OpenLayers.Control.PanPanel>.
  13  *
  14  * Inherits from:
  15  *  - <OpenLayers.Control>
  16  */
  17 OpenLayers.Control.Pan = OpenLayers.Class(OpenLayers.Control, {
  18
  19     /**
  20      * APIProperty: slideFactor
  21      * {Integer} Number of pixels by which we'll pan the map in any direction
  22      *     on clicking the arrow buttons.
  23      */
  24     slideFactor: 50,
  25
  26     /**
  27      * Property: direction
  28      * {String} in {'North', 'South', 'East', 'West'}
  29      */
  30     direction: null,
  31
  32     /**
  33      * Property: type
  34      * {String} The type of <OpenLayers.Control> -- When added to a
  35      *     <Control.Panel>, 'type' is used by the panel to determine how to
  36      *     handle our events.
  37      */
  38     type: OpenLayers.Control.TYPE_BUTTON,
  39
  40     /**
  41      * Constructor: OpenLayers.Control.Pan
  42      * Control which handles the panning (in any of the cardinal directions)
  43      *     of the map by a set px distance.
  44      *
  45      * Parameters:
  46      * direction - {String} The direction this button should pan.
  47      * options - {Object} An optional object whose properties will be used
  48      *     to extend the control.
  49      */
  50     initialize: function(direction, options) {
  51
  52         this.direction = direction;
  53         this.CLASS_NAME += this.direction;
  54
  55         OpenLayers.Control.prototype.initialize.apply(this, [options]);
  56     },
  57
  58     /**
  59      * Method: trigger
  60      */
  61     trigger: function(){
  62
  63         switch (this.direction) {
  64             case OpenLayers.Control.Pan.NORTH:
  65                 this.map.pan(0, -this.slideFactor);
  66                 break;
  67             case OpenLayers.Control.Pan.SOUTH:
  68                 this.map.pan(0, this.slideFactor);
  69                 break;
  70             case OpenLayers.Control.Pan.WEST:
  71                 this.map.pan(-this.slideFactor, 0);
  72                 break;
  73             case OpenLayers.Control.Pan.EAST:
  74                 this.map.pan(this.slideFactor, 0);
  75                 break;
  76         }
  77     },
  78
  79     CLASS_NAME: "OpenLayers.Control.Pan"
  80 });
  81
  82 OpenLayers.Control.Pan.NORTH = "North";
  83 OpenLayers.Control.Pan.SOUTH = "South";
  84 OpenLayers.Control.Pan.EAST = "East";
  85 OpenLayers.Control.Pan.WEST = "West";