openlayers/lib/OpenLayers/Control/Navigation.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/ZoomBox.js
   7  * @requires OpenLayers/Control/DragPan.js
   8  * @requires OpenLayers/Handler/MouseWheel.js
   9  * @requires OpenLayers/Handler/Click.js
  10  */
  11
  12 /**
  13  * Class: OpenLayers.Control.Navigation
  14  * The navigation control handles map browsing with mouse events (dragging,
  15  *     double-clicking, and scrolling the wheel).  Create a new navigation
  16  *     control with the <OpenLayers.Control.Navigation> control.
  17  *
  18  *     Note that this control is added to the map by default (if no controls
  19  *     array is sent in the options object to the <OpenLayers.Map>
  20  *     constructor).
  21  *
  22  * Inherits:
  23  *  - <OpenLayers.Control>
  24  */
  25 OpenLayers.Control.Navigation = OpenLayers.Class(OpenLayers.Control, {
  26
  27     /**
  28      * Property: dragPan
  29      * {<OpenLayers.Control.DragPan>}
  30      */
  31     dragPan: null,
  32
  33     /**
  34      * APIProprety: dragPanOptions
  35      * {Object} Options passed to the DragPan control.
  36      */
  37     dragPanOptions: null,
  38
  39     /**
  40      * Property: zoomBox
  41      * {<OpenLayers.Control.ZoomBox>}
  42      */
  43     zoomBox: null,
  44
  45     /**
  46      * APIProperty: zoomWheelEnabled
  47      * {Boolean} Whether the mousewheel should zoom the map
  48      */
  49     zoomWheelEnabled: true,
  50
  51     /**
  52      * APIProperty: handleRightClicks
  53      * {Boolean} Whether or not to handle right clicks. Default is false.
  54      */
  55     handleRightClicks: false,
  56
  57     /**
  58      * APIProperty: zoomBoxKeyMask
  59      * {Integer} <OpenLayers.Handler> key code of the key, which has to be
  60      *    pressed, while drawing the zoom box with the mouse on the screen.
  61      *    You should probably set handleRightClicks to true if you use this
  62      *    with MOD_CTRL, to disable the context menu for machines which use
  63      *    CTRL-Click as a right click.
  64      * Default: <OpenLayers.Handler.MOD_SHIFT
  65      */
  66     zoomBoxKeyMask: OpenLayers.Handler.MOD_SHIFT,
  67
  68     /**
  69      * Constructor: OpenLayers.Control.Navigation
  70      * Create a new navigation control
  71      *
  72      * Parameters:
  73      * options - {Object} An optional object whose properties will be set on
  74      *                    the control
  75      */
  76     initialize: function(options) {
  77         this.handlers = {};
  78         OpenLayers.Control.prototype.initialize.apply(this, arguments);
  79     },
  80
  81     /**
  82      * Method: destroy
  83      * The destroy method is used to perform any clean up before the control
  84      * is dereferenced.  Typically this is where event listeners are removed
  85      * to prevent memory leaks.
  86      */
  87     destroy: function() {
  88         this.deactivate();
  89
  90         if (this.dragPan) {
  91             this.dragPan.destroy();
  92         }
  93         this.dragPan = null;
  94
  95         if (this.zoomBox) {
  96             this.zoomBox.destroy();
  97         }
  98         this.zoomBox = null;
  99         OpenLayers.Control.prototype.destroy.apply(this,arguments);
 100     },
 101
 102     /**
 103      * Method: activate
 104      */
 105     activate: function() {
 106         this.dragPan.activate();
 107         if (this.zoomWheelEnabled) {
 108             this.handlers.wheel.activate();
 109         }
 110         this.handlers.click.activate();
 111         this.zoomBox.activate();
 112         return OpenLayers.Control.prototype.activate.apply(this,arguments);
 113     },
 114
 115     /**
 116      * Method: deactivate
 117      */
 118     deactivate: function() {
 119         this.zoomBox.deactivate();
 120         this.dragPan.deactivate();
 121         this.handlers.click.deactivate();
 122         this.handlers.wheel.deactivate();
 123         return OpenLayers.Control.prototype.deactivate.apply(this,arguments);
 124     },
 125
 126     /**
 127      * Method: draw
 128      */
 129     draw: function() {
 130         // disable right mouse context menu for support of right click events
 131         if (this.handleRightClicks) {
 132             this.map.viewPortDiv.oncontextmenu = function () { return false;};
 133         }
 134
 135         var clickCallbacks = {
 136             'dblclick': this.defaultDblClick,
 137             'dblrightclick': this.defaultDblRightClick
 138         };
 139         var clickOptions = {
 140             'double': true,
 141             'stopDouble': true
 142         };
 143         this.handlers.click = new OpenLayers.Handler.Click(
 144             this, clickCallbacks, clickOptions
 145         );
 146         this.dragPan = new OpenLayers.Control.DragPan(
 147             OpenLayers.Util.extend({map: this.map}, this.dragPanOptions)
 148         );
 149         this.zoomBox = new OpenLayers.Control.ZoomBox(
 150                     {map: this.map, keyMask: this.zoomBoxKeyMask});
 151         this.dragPan.draw();
 152         this.zoomBox.draw();
 153         this.handlers.wheel = new OpenLayers.Handler.MouseWheel(
 154                                     this, {"up"  : this.wheelUp,
 155                                            "down": this.wheelDown} );
 156         this.activate();
 157     },
 158
 159     /**
 160      * Method: defaultDblClick
 161      *
 162      * Parameters:
 163      * evt - {Event}
 164      */
 165     defaultDblClick: function (evt) {
 166         var newCenter = this.map.getLonLatFromViewPortPx( evt.xy );
 167         this.map.setCenter(newCenter, this.map.zoom + 1);
 168     },
 169
 170     /**
 171      * Method: defaultDblRightClick
 172      *
 173      * Parameters:
 174      * evt - {Event}
 175      */
 176     defaultDblRightClick: function (evt) {
 177         var newCenter = this.map.getLonLatFromViewPortPx( evt.xy );
 178         this.map.setCenter(newCenter, this.map.zoom - 1);
 179     },
 180
 181     /**
 182      * Method: wheelChange
 183      *
 184      * Parameters:
 185      * evt - {Event}
 186      * deltaZ - {Integer}
 187      */
 188     wheelChange: function(evt, deltaZ) {
 189         var newZoom = this.map.getZoom() + deltaZ;
 190         if (!this.map.isValidZoomLevel(newZoom)) {
 191             return;
 192         }
 193         var size    = this.map.getSize();
 194         var deltaX  = size.w/2 - evt.xy.x;
 195         var deltaY  = evt.xy.y - size.h/2;
 196         var newRes  = this.map.baseLayer.getResolutionForZoom(newZoom);
 197         var zoomPoint = this.map.getLonLatFromPixel(evt.xy);
 198         var newCenter = new OpenLayers.LonLat(
 199                             zoomPoint.lon + deltaX * newRes,
 200                             zoomPoint.lat + deltaY * newRes );
 201         this.map.setCenter( newCenter, newZoom );
 202     },
 203
 204     /**
 205      * Method: wheelUp
 206      * User spun scroll wheel up
 207      *
 208      * Parameters:
 209      * evt - {Event}
 210      */
 211     wheelUp: function(evt) {
 212         this.wheelChange(evt, 1);
 213     },
 214
 215     /**
 216      * Method: wheelDown
 217      * User spun scroll wheel down
 218      *
 219      * Parameters:
 220      * evt - {Event}
 221      */
 222     wheelDown: function(evt) {
 223         this.wheelChange(evt, -1);
 224     },
 225
 226     /**
 227      * Method: disableZoomWheel
 228      */
 229
 230     disableZoomWheel : function() {
 231         this.zoomWheelEnabled = false;
 232         this.handlers.wheel.deactivate();
 233     },
 234
 235     /**
 236      * Method: enableZoomWheel
 237      */
 238
 239     enableZoomWheel : function() {
 240         this.zoomWheelEnabled = true;
 241         if (this.active) {
 242             this.handlers.wheel.activate();
 243         }
 244     },
 245
 246     CLASS_NAME: "OpenLayers.Control.Navigation"
 247 });