[76] | 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 | * @requires OpenLayers/Control.js |
---|
| 8 | * @requires OpenLayers/Control/Button.js |
---|
| 9 | */ |
---|
| 10 | |
---|
| 11 | /** |
---|
| 12 | * Class: OpenLayers.Control.NavigationHistory |
---|
| 13 | * A navigation history control. This is a meta-control, that creates two |
---|
| 14 | * dependent controls: <previous> and <next>. Call the trigger method |
---|
| 15 | * on the <previous> and <next> controls to restore previous and next |
---|
| 16 | * history states. The previous and next controls will become active |
---|
| 17 | * when there are available states to restore and will become deactive |
---|
| 18 | * when there are no states to restore. |
---|
| 19 | * |
---|
| 20 | * Inherits from: |
---|
| 21 | * - <OpenLayers.Control> |
---|
| 22 | */ |
---|
| 23 | OpenLayers.Control.NavigationHistory = OpenLayers.Class(OpenLayers.Control, { |
---|
| 24 | |
---|
| 25 | /** |
---|
| 26 | * Property: type |
---|
| 27 | * {String} Note that this control is not intended to be added directly |
---|
| 28 | * to a control panel. Instead, add the sub-controls previous and |
---|
| 29 | * next. These sub-controls are button type controls that activate |
---|
| 30 | * and deactivate themselves. If this parent control is added to |
---|
| 31 | * a panel, it will act as a toggle. |
---|
| 32 | */ |
---|
| 33 | type: OpenLayers.Control.TYPE_TOGGLE, |
---|
| 34 | |
---|
| 35 | /** |
---|
| 36 | * APIProperty: previous |
---|
| 37 | * {<OpenLayers.Control>} A button type control whose trigger method restores |
---|
| 38 | * the previous state managed by this control. |
---|
| 39 | */ |
---|
| 40 | previous: null, |
---|
| 41 | |
---|
| 42 | /** |
---|
| 43 | * APIProperty: previousOptions |
---|
| 44 | * {Object} Set this property on the options argument of the constructor |
---|
| 45 | * to set optional properties on the <previous> control. |
---|
| 46 | */ |
---|
| 47 | previousOptions: null, |
---|
| 48 | |
---|
| 49 | /** |
---|
| 50 | * APIProperty: next |
---|
| 51 | * {<OpenLayers.Control>} A button type control whose trigger method restores |
---|
| 52 | * the next state managed by this control. |
---|
| 53 | */ |
---|
| 54 | next: null, |
---|
| 55 | |
---|
| 56 | /** |
---|
| 57 | * APIProperty: nextOptions |
---|
| 58 | * {Object} Set this property on the options argument of the constructor |
---|
| 59 | * to set optional properties on the <next> control. |
---|
| 60 | */ |
---|
| 61 | nextOptions: null, |
---|
| 62 | |
---|
| 63 | /** |
---|
| 64 | * APIProperty: limit |
---|
| 65 | * {Integer} Optional limit on the number of history items to retain. If |
---|
| 66 | * null, there is no limit. Default is 50. |
---|
| 67 | */ |
---|
| 68 | limit: 50, |
---|
| 69 | |
---|
| 70 | /** |
---|
| 71 | * APIProperty: autoActivate |
---|
| 72 | * {Boolean} Activate the control when it is added to a map. Default is |
---|
| 73 | * true. |
---|
| 74 | */ |
---|
| 75 | autoActivate: true, |
---|
| 76 | |
---|
| 77 | /** |
---|
| 78 | * Property: clearOnDeactivate |
---|
| 79 | * {Boolean} Clear the history when the control is deactivated. Default |
---|
| 80 | * is false. |
---|
| 81 | */ |
---|
| 82 | clearOnDeactivate: false, |
---|
| 83 | |
---|
| 84 | /** |
---|
| 85 | * Property: registry |
---|
| 86 | * {Object} An object with keys corresponding to event types. Values |
---|
| 87 | * are functions that return an object representing the current state. |
---|
| 88 | */ |
---|
| 89 | registry: null, |
---|
| 90 | |
---|
| 91 | /** |
---|
| 92 | * Property: nextStack |
---|
| 93 | * {Array} Array of items in the history. |
---|
| 94 | */ |
---|
| 95 | nextStack: null, |
---|
| 96 | |
---|
| 97 | /** |
---|
| 98 | * Property: previousStack |
---|
| 99 | * {Array} List of items in the history. First item represents the current |
---|
| 100 | * state. |
---|
| 101 | */ |
---|
| 102 | previousStack: null, |
---|
| 103 | |
---|
| 104 | /** |
---|
| 105 | * Property: listeners |
---|
| 106 | * {Object} An object containing properties corresponding to event types. |
---|
| 107 | * This object is used to configure the control and is modified on |
---|
| 108 | * construction. |
---|
| 109 | */ |
---|
| 110 | listeners: null, |
---|
| 111 | |
---|
| 112 | /** |
---|
| 113 | * Property: restoring |
---|
| 114 | * {Boolean} Currently restoring a history state. This is set to true |
---|
| 115 | * before calling restore and set to false after restore returns. |
---|
| 116 | */ |
---|
| 117 | restoring: false, |
---|
| 118 | |
---|
| 119 | /** |
---|
| 120 | * Constructor: OpenLayers.Control.NavigationHistory |
---|
| 121 | * |
---|
| 122 | * Parameters: |
---|
| 123 | * options - {Object} An optional object whose properties will be used |
---|
| 124 | * to extend the control. |
---|
| 125 | */ |
---|
| 126 | initialize: function(options) { |
---|
| 127 | OpenLayers.Control.prototype.initialize.apply(this, [options]); |
---|
| 128 | |
---|
| 129 | this.registry = OpenLayers.Util.extend({ |
---|
| 130 | "moveend": this.getState |
---|
| 131 | }, this.registry); |
---|
| 132 | |
---|
| 133 | var previousOptions = { |
---|
| 134 | trigger: OpenLayers.Function.bind(this.previousTrigger, this), |
---|
| 135 | displayClass: this.displayClass + " " + this.displayClass + "Previous" |
---|
| 136 | }; |
---|
| 137 | OpenLayers.Util.extend(previousOptions, this.previousOptions); |
---|
| 138 | this.previous = new OpenLayers.Control.Button(previousOptions); |
---|
| 139 | |
---|
| 140 | var nextOptions = { |
---|
| 141 | trigger: OpenLayers.Function.bind(this.nextTrigger, this), |
---|
| 142 | displayClass: this.displayClass + " " + this.displayClass + "Next" |
---|
| 143 | }; |
---|
| 144 | OpenLayers.Util.extend(nextOptions, this.nextOptions); |
---|
| 145 | this.next = new OpenLayers.Control.Button(nextOptions); |
---|
| 146 | |
---|
| 147 | this.clear(); |
---|
| 148 | }, |
---|
| 149 | |
---|
| 150 | /** |
---|
| 151 | * Method: onPreviousChange |
---|
| 152 | * Called when the previous history stack changes. |
---|
| 153 | * |
---|
| 154 | * Parameters: |
---|
| 155 | * state - {Object} An object representing the state to be restored |
---|
| 156 | * if previous is triggered again or null if no previous states remain. |
---|
| 157 | * length - {Integer} The number of remaining previous states that can |
---|
| 158 | * be restored. |
---|
| 159 | */ |
---|
| 160 | onPreviousChange: function(state, length) { |
---|
| 161 | if(state && !this.previous.active) { |
---|
| 162 | this.previous.activate(); |
---|
| 163 | } else if(!state && this.previous.active) { |
---|
| 164 | this.previous.deactivate(); |
---|
| 165 | } |
---|
| 166 | }, |
---|
| 167 | |
---|
| 168 | /** |
---|
| 169 | * Method: onNextChange |
---|
| 170 | * Called when the next history stack changes. |
---|
| 171 | * |
---|
| 172 | * Parameters: |
---|
| 173 | * state - {Object} An object representing the state to be restored |
---|
| 174 | * if next is triggered again or null if no next states remain. |
---|
| 175 | * length - {Integer} The number of remaining next states that can |
---|
| 176 | * be restored. |
---|
| 177 | */ |
---|
| 178 | onNextChange: function(state, length) { |
---|
| 179 | if(state && !this.next.active) { |
---|
| 180 | this.next.activate(); |
---|
| 181 | } else if(!state && this.next.active) { |
---|
| 182 | this.next.deactivate(); |
---|
| 183 | } |
---|
| 184 | }, |
---|
| 185 | |
---|
| 186 | /** |
---|
| 187 | * APIMethod: destroy |
---|
| 188 | * Destroy the control. |
---|
| 189 | */ |
---|
| 190 | destroy: function() { |
---|
| 191 | OpenLayers.Control.prototype.destroy.apply(this); |
---|
| 192 | this.previous.destroy(); |
---|
| 193 | this.next.destroy(); |
---|
| 194 | this.deactivate(); |
---|
| 195 | for(var prop in this) { |
---|
| 196 | this[prop] = null; |
---|
| 197 | } |
---|
| 198 | }, |
---|
| 199 | |
---|
| 200 | /** |
---|
| 201 | * Method: setMap |
---|
| 202 | * Set the map property for the control and <previous> and <next> child |
---|
| 203 | * controls. |
---|
| 204 | * |
---|
| 205 | * Parameters: |
---|
| 206 | * map - {<OpenLayers.Map>} |
---|
| 207 | */ |
---|
| 208 | setMap: function(map) { |
---|
| 209 | this.map = map; |
---|
| 210 | this.next.setMap(map); |
---|
| 211 | this.previous.setMap(map); |
---|
| 212 | }, |
---|
| 213 | |
---|
| 214 | /** |
---|
| 215 | * Method: draw |
---|
| 216 | * Called when the control is added to the map. |
---|
| 217 | */ |
---|
| 218 | draw: function() { |
---|
| 219 | OpenLayers.Control.prototype.draw.apply(this, arguments); |
---|
| 220 | this.next.draw(); |
---|
| 221 | this.previous.draw(); |
---|
| 222 | }, |
---|
| 223 | |
---|
| 224 | /** |
---|
| 225 | * Method: previousTrigger |
---|
| 226 | * Restore the previous state. If no items are in the previous history |
---|
| 227 | * stack, this has no effect. |
---|
| 228 | * |
---|
| 229 | * Returns: |
---|
| 230 | * {Object} Item representing state that was restored. Undefined if no |
---|
| 231 | * items are in the previous history stack. |
---|
| 232 | */ |
---|
| 233 | previousTrigger: function() { |
---|
| 234 | var current = this.previousStack.shift(); |
---|
| 235 | var state = this.previousStack.shift(); |
---|
| 236 | if(state != undefined) { |
---|
| 237 | this.nextStack.unshift(current); |
---|
| 238 | this.previousStack.unshift(state); |
---|
| 239 | this.restoring = true; |
---|
| 240 | this.restore(state); |
---|
| 241 | this.restoring = false; |
---|
| 242 | this.onNextChange(this.nextStack[0], this.nextStack.length); |
---|
| 243 | this.onPreviousChange( |
---|
| 244 | this.previousStack[1], this.previousStack.length - 1 |
---|
| 245 | ); |
---|
| 246 | } else { |
---|
| 247 | this.previousStack.unshift(current); |
---|
| 248 | } |
---|
| 249 | return state; |
---|
| 250 | }, |
---|
| 251 | |
---|
| 252 | /** |
---|
| 253 | * APIMethod: nextTrigger |
---|
| 254 | * Restore the next state. If no items are in the next history |
---|
| 255 | * stack, this has no effect. The next history stack is populated |
---|
| 256 | * as states are restored from the previous history stack. |
---|
| 257 | * |
---|
| 258 | * Returns: |
---|
| 259 | * {Object} Item representing state that was restored. Undefined if no |
---|
| 260 | * items are in the next history stack. |
---|
| 261 | */ |
---|
| 262 | nextTrigger: function() { |
---|
| 263 | var state = this.nextStack.shift(); |
---|
| 264 | if(state != undefined) { |
---|
| 265 | this.previousStack.unshift(state); |
---|
| 266 | this.restoring = true; |
---|
| 267 | this.restore(state); |
---|
| 268 | this.restoring = false; |
---|
| 269 | this.onNextChange(this.nextStack[0], this.nextStack.length); |
---|
| 270 | this.onPreviousChange( |
---|
| 271 | this.previousStack[1], this.previousStack.length - 1 |
---|
| 272 | ); |
---|
| 273 | } |
---|
| 274 | return state; |
---|
| 275 | }, |
---|
| 276 | |
---|
| 277 | /** |
---|
| 278 | * APIMethod: clear |
---|
| 279 | * Clear history. |
---|
| 280 | */ |
---|
| 281 | clear: function() { |
---|
| 282 | this.previousStack = []; |
---|
| 283 | this.previous.deactivate(); |
---|
| 284 | this.nextStack = []; |
---|
| 285 | this.next.deactivate(); |
---|
| 286 | }, |
---|
| 287 | |
---|
| 288 | /** |
---|
| 289 | * Method: getState |
---|
| 290 | * Get the current state and return it. |
---|
| 291 | * |
---|
| 292 | * Returns: |
---|
| 293 | * {Object} An object representing the current state. |
---|
| 294 | */ |
---|
| 295 | getState: function() { |
---|
| 296 | return { |
---|
| 297 | center: this.map.getCenter(), |
---|
| 298 | resolution: this.map.getResolution(), |
---|
| 299 | projection: this.map.getProjectionObject(), |
---|
| 300 | units: this.map.getProjectionObject().getUnits() || |
---|
| 301 | this.map.units || this.map.baseLayer.units |
---|
| 302 | }; |
---|
| 303 | }, |
---|
| 304 | |
---|
| 305 | /** |
---|
| 306 | * Method: restore |
---|
| 307 | * Update the state with the given object. |
---|
| 308 | * |
---|
| 309 | * Parameters: |
---|
| 310 | * state - {Object} An object representing the state to restore. |
---|
| 311 | */ |
---|
| 312 | restore: function(state) { |
---|
| 313 | var center, zoom; |
---|
| 314 | if (this.map.getProjectionObject() == state.projection) { |
---|
| 315 | zoom = this.map.getZoomForResolution(state.resolution); |
---|
| 316 | center = state.center; |
---|
| 317 | } else { |
---|
| 318 | center = state.center.clone(); |
---|
| 319 | center.transform(state.projection, this.map.getProjectionObject()); |
---|
| 320 | var sourceUnits = state.units; |
---|
| 321 | var targetUnits = this.map.getProjectionObject().getUnits() || |
---|
| 322 | this.map.units || this.map.baseLayer.units; |
---|
| 323 | var resolutionFactor = sourceUnits && targetUnits ? |
---|
| 324 | OpenLayers.INCHES_PER_UNIT[sourceUnits] / OpenLayers.INCHES_PER_UNIT[targetUnits] : 1; |
---|
| 325 | zoom = this.map.getZoomForResolution(resolutionFactor*state.resolution); |
---|
| 326 | } |
---|
| 327 | this.map.setCenter(center, zoom); |
---|
| 328 | }, |
---|
| 329 | |
---|
| 330 | /** |
---|
| 331 | * Method: setListeners |
---|
| 332 | * Sets functions to be registered in the listeners object. |
---|
| 333 | */ |
---|
| 334 | setListeners: function() { |
---|
| 335 | this.listeners = {}; |
---|
| 336 | for(var type in this.registry) { |
---|
| 337 | this.listeners[type] = OpenLayers.Function.bind(function() { |
---|
| 338 | if(!this.restoring) { |
---|
| 339 | var state = this.registry[type].apply(this, arguments); |
---|
| 340 | this.previousStack.unshift(state); |
---|
| 341 | if(this.previousStack.length > 1) { |
---|
| 342 | this.onPreviousChange( |
---|
| 343 | this.previousStack[1], this.previousStack.length - 1 |
---|
| 344 | ); |
---|
| 345 | } |
---|
| 346 | if(this.previousStack.length > (this.limit + 1)) { |
---|
| 347 | this.previousStack.pop(); |
---|
| 348 | } |
---|
| 349 | if(this.nextStack.length > 0) { |
---|
| 350 | this.nextStack = []; |
---|
| 351 | this.onNextChange(null, 0); |
---|
| 352 | } |
---|
| 353 | } |
---|
| 354 | return true; |
---|
| 355 | }, this); |
---|
| 356 | } |
---|
| 357 | }, |
---|
| 358 | |
---|
| 359 | /** |
---|
| 360 | * APIMethod: activate |
---|
| 361 | * Activate the control. This registers any listeners. |
---|
| 362 | * |
---|
| 363 | * Returns: |
---|
| 364 | * {Boolean} Control successfully activated. |
---|
| 365 | */ |
---|
| 366 | activate: function() { |
---|
| 367 | var activated = false; |
---|
| 368 | if(this.map) { |
---|
| 369 | if(OpenLayers.Control.prototype.activate.apply(this)) { |
---|
| 370 | if(this.listeners == null) { |
---|
| 371 | this.setListeners(); |
---|
| 372 | } |
---|
| 373 | for(var type in this.listeners) { |
---|
| 374 | this.map.events.register(type, this, this.listeners[type]); |
---|
| 375 | } |
---|
| 376 | activated = true; |
---|
| 377 | if(this.previousStack.length == 0) { |
---|
| 378 | this.initStack(); |
---|
| 379 | } |
---|
| 380 | } |
---|
| 381 | } |
---|
| 382 | return activated; |
---|
| 383 | }, |
---|
| 384 | |
---|
| 385 | /** |
---|
| 386 | * Method: initStack |
---|
| 387 | * Called after the control is activated if the previous history stack is |
---|
| 388 | * empty. |
---|
| 389 | */ |
---|
| 390 | initStack: function() { |
---|
| 391 | if(this.map.getCenter()) { |
---|
| 392 | this.listeners.moveend(); |
---|
| 393 | } |
---|
| 394 | }, |
---|
| 395 | |
---|
| 396 | /** |
---|
| 397 | * APIMethod: deactivate |
---|
| 398 | * Deactivate the control. This unregisters any listeners. |
---|
| 399 | * |
---|
| 400 | * Returns: |
---|
| 401 | * {Boolean} Control successfully deactivated. |
---|
| 402 | */ |
---|
| 403 | deactivate: function() { |
---|
| 404 | var deactivated = false; |
---|
| 405 | if(this.map) { |
---|
| 406 | if(OpenLayers.Control.prototype.deactivate.apply(this)) { |
---|
| 407 | for(var type in this.listeners) { |
---|
| 408 | this.map.events.unregister( |
---|
| 409 | type, this, this.listeners[type] |
---|
| 410 | ); |
---|
| 411 | } |
---|
| 412 | if(this.clearOnDeactivate) { |
---|
| 413 | this.clear(); |
---|
| 414 | } |
---|
| 415 | deactivated = true; |
---|
| 416 | } |
---|
| 417 | } |
---|
| 418 | return deactivated; |
---|
| 419 | }, |
---|
| 420 | |
---|
| 421 | CLASS_NAME: "OpenLayers.Control.NavigationHistory" |
---|
| 422 | }); |
---|
| 423 | |
---|