Files
openlayers/lib/OpenLayers/Layer/Vector.js
ahocevar cc2e19d789 added support for text labels. This also adds getCentroid methods to all
geometries. Thanks crschmidt for the great help with this patch, and 
thanks to camptocamp for the initial work on this and rcoup for creating 
the first patches. r=crschmidt (closes #1895)


git-svn-id: http://svn.openlayers.org/trunk/openlayers@9262 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf
2009-04-10 16:05:26 +00:00

798 lines
27 KiB
JavaScript

/* Copyright (c) 2006-2008 MetaCarta, Inc., published under the Clear BSD
* license. See http://svn.openlayers.org/trunk/openlayers/license.txt for the
* full text of the license. */
/**
* @requires OpenLayers/Layer.js
* @requires OpenLayers/Renderer.js
* @requires OpenLayers/StyleMap.js
* @requires OpenLayers/Feature/Vector.js
* @requires OpenLayers/Console.js
*/
/**
* Class: OpenLayers.Layer.Vector
* Instances of OpenLayers.Layer.Vector are used to render vector data from
* a variety of sources. Create a new vector layer with the
* <OpenLayers.Layer.Vector> constructor.
*
* Inherits from:
* - <OpenLayers.Layer>
*/
OpenLayers.Layer.Vector = OpenLayers.Class(OpenLayers.Layer, {
/**
* Constant: EVENT_TYPES
* {Array(String)} Supported application event types. Register a listener
* for a particular event with the following syntax:
* (code)
* layer.events.register(type, obj, listener);
* (end)
*
* Listeners will be called with a reference to an event object. The
* properties of this event depends on exactly what happened.
*
* All event objects have at least the following properties:
* object - {Object} A reference to layer.events.object.
* element - {DOMElement} A reference to layer.events.element.
*
* Supported map event types (in addition to those from <OpenLayers.Layer>):
* beforefeatureadded - Triggered before a feature is added. Listeners
* will receive an object with a *feature* property referencing the
* feature to be added. To stop the feature from being added, a
* listener should return false.
* beforefeaturesadded - Triggered before an array of features is added.
* Listeners will receive an object with a *features* property
* referencing the feature to be added. To stop the features from
* being added, a listener should return false.
* featureadded - Triggered after a feature is added. The event
* object passed to listeners will have a *feature* property with a
* reference to the added feature.
* featuresadded - Triggered after features are added. The event
* object passed to listeners will have a *features* property with a
* reference to an array of added features.
* beforefeatureremoved - Triggered before a feature is removed. Listeners
* will receive an object with a *feature* property referencing the
* feature to be removed.
* featureremoved - Triggerd after a feature is removed. The event
* object passed to listeners will have a *feature* property with a
* reference to the removed feature.
* featuresremoved - Triggered after features are removed. The event
* object passed to listeners will have a *features* property with a
* reference to an array of removed features.
* featureselected - Triggered after a feature is selected. Listeners
* will receive an object with a *feature* property referencing the
* selected feature.
* featureunselected - Triggered after a feature is unselected.
* Listeners will receive an object with a *feature* property
* referencing the unselected feature.
* beforefeaturemodified - Triggered when a feature is selected to
* be modified. Listeners will receive an object with a *feature*
* property referencing the selected feature.
* featuremodified - Triggered when a feature has been modified.
* Listeners will receive an object with a *feature* property referencing
* the modified feature.
* afterfeaturemodified - Triggered when a feature is finished being modified.
* Listeners will receive an object with a *feature* property referencing
* the modified feature.
* vertexmodified - Triggered when a vertex within any feature geometry
* has been modified. Listeners will receive an object with a
* *feature* property referencing the modified feature, a *vertex*
* property referencing the vertex modified (always a point geometry),
* and a *pixel* property referencing the pixel location of the
* modification.
* sketchmodified - Triggered when a feature sketch bound for this layer
* is modified. Listeners will receive an object with a *vertex*
* property referencing the modified vertex.
* sketchcomplete - Triggered when a feature sketch bound for this layer
* is complete. Listeners will receive an object with a *feature*
* property referencing the sketch feature. By returning false, a
* listener can stop the sketch feature from being added to the layer.
* refresh - Triggered when something wants a strategy to ask the protocol
* for a new set of features.
*/
EVENT_TYPES: ["beforefeatureadded", "beforefeaturesadded",
"featureadded", "featuresadded",
"beforefeatureremoved", "featureremoved", "featuresremoved",
"beforefeatureselected", "featureselected", "featureunselected",
"beforefeaturemodified", "featuremodified", "afterfeaturemodified",
"vertexmodified", "sketchmodified", "sketchcomplete",
"refresh"],
/**
* APIProperty: isBaseLayer
* {Boolean} The layer is a base layer. Default is true. Set this property
* in the layer options
*/
isBaseLayer: false,
/**
* APIProperty: isFixed
* {Boolean} Whether the layer remains in one place while dragging the
* map.
*/
isFixed: false,
/**
* APIProperty: isVector
* {Boolean} Whether the layer is a vector layer.
*/
isVector: true,
/**
* APIProperty: features
* {Array(<OpenLayers.Feature.Vector>)}
*/
features: null,
/**
* Property: selectedFeatures
* {Array(<OpenLayers.Feature.Vector>)}
*/
selectedFeatures: null,
/**
* Property: unrenderedFeatures
* {Object} hash of features, keyed by feature.id, that the renderer
* failed to draw
*/
unrenderedFeatures: null,
/**
* APIProperty: reportError
* {Boolean} report friendly error message when loading of renderer
* fails.
*/
reportError: true,
/**
* APIProperty: style
* {Object} Default style for the layer
*/
style: null,
/**
* Property: styleMap
* {<OpenLayers.StyleMap>}
*/
styleMap: null,
/**
* Property: strategies
* {Array(<OpenLayers.Strategy>})} Optional list of strategies for the layer.
*/
strategies: null,
/**
* Property: protocol
* {<OpenLayers.Protocol>} Optional protocol for the layer.
*/
protocol: null,
/**
* Property: renderers
* {Array(String)} List of supported Renderer classes. Add to this list to
* add support for additional renderers. This list is ordered:
* the first renderer which returns true for the 'supported()'
* method will be used, if not defined in the 'renderer' option.
*/
renderers: ['SVG', 'VML', 'Canvas'],
/**
* Property: renderer
* {<OpenLayers.Renderer>}
*/
renderer: null,
/**
* APIProperty: rendererOptions
* {Object} Options for the renderer. See {<OpenLayers.Renderer>} for
* supported options.
*/
rendererOptions: null,
/**
* APIProperty: geometryType
* {String} geometryType allows you to limit the types of geometries this
* layer supports. This should be set to something like
* "OpenLayers.Geometry.Point" to limit types.
*/
geometryType: null,
/**
* Property: drawn
* {Boolean} Whether the Vector Layer features have been drawn yet.
*/
drawn: false,
/**
* Constructor: OpenLayers.Layer.Vector
* Create a new vector layer
*
* Parameters:
* name - {String} A name for the layer
* options - {Object} Optional object with non-default properties to set on
* the layer.
*
* Returns:
* {<OpenLayers.Layer.Vector>} A new vector layer
*/
initialize: function(name, options) {
// concatenate events specific to vector with those from the base
this.EVENT_TYPES =
OpenLayers.Layer.Vector.prototype.EVENT_TYPES.concat(
OpenLayers.Layer.prototype.EVENT_TYPES
);
OpenLayers.Layer.prototype.initialize.apply(this, arguments);
// allow user-set renderer, otherwise assign one
if (!this.renderer || !this.renderer.supported()) {
this.assignRenderer();
}
// if no valid renderer found, display error
if (!this.renderer || !this.renderer.supported()) {
this.renderer = null;
this.displayError();
}
if (!this.styleMap) {
this.styleMap = new OpenLayers.StyleMap();
}
this.features = [];
this.selectedFeatures = [];
this.unrenderedFeatures = {};
// Allow for custom layer behavior
if(this.strategies){
for(var i=0, len=this.strategies.length; i<len; i++) {
this.strategies[i].setLayer(this);
}
}
},
/**
* APIMethod: destroy
* Destroy this layer
*/
destroy: function() {
if (this.strategies) {
var strategy, i, len;
for(i=0, len=this.strategies.length; i<len; i++) {
strategy = this.strategies[i];
if(strategy.autoDestroy) {
strategy.destroy();
}
}
this.strategies = null;
}
if (this.protocol) {
if(this.protocol.autoDestroy) {
this.protocol.destroy();
}
this.protocol = null;
}
this.destroyFeatures();
this.features = null;
this.selectedFeatures = null;
this.unrenderedFeatures = null;
if (this.renderer) {
this.renderer.destroy();
}
this.renderer = null;
this.geometryType = null;
this.drawn = null;
OpenLayers.Layer.prototype.destroy.apply(this, arguments);
},
/**
* Method: refresh
* Ask the layer to request features again and redraw them. Triggers
* the refresh event if the layer is in range and visible.
*
* Parameters:
* obj - {Object} Optional object with properties for any listener of
* the refresh event.
*/
refresh: function(obj) {
if(this.calculateInRange() && this.visibility) {
this.events.triggerEvent("refresh", obj);
}
},
/**
* Method: assignRenderer
* Iterates through the available renderer implementations and selects
* and assigns the first one whose "supported()" function returns true.
*/
assignRenderer: function() {
for (var i=0, len=this.renderers.length; i<len; i++) {
var rendererClass = OpenLayers.Renderer[this.renderers[i]];
if (rendererClass && rendererClass.prototype.supported()) {
this.renderer = new rendererClass(this.div,
this.rendererOptions);
break;
}
}
},
/**
* Method: displayError
* Let the user know their browser isn't supported.
*/
displayError: function() {
if (this.reportError) {
OpenLayers.Console.userError(OpenLayers.i18n("browserNotSupported",
{'renderers':this.renderers.join("\n")}));
}
},
/**
* Method: setMap
* The layer has been added to the map.
*
* If there is no renderer set, the layer can't be used. Remove it.
* Otherwise, give the renderer a reference to the map and set its size.
*
* Parameters:
* map - {<OpenLayers.Map>}
*/
setMap: function(map) {
OpenLayers.Layer.prototype.setMap.apply(this, arguments);
if (!this.renderer) {
this.map.removeLayer(this);
} else {
this.renderer.map = this.map;
this.renderer.setSize(this.map.getSize());
}
if(this.strategies) {
var strategy, i, len;
for(i=0, len=this.strategies.length; i<len; i++) {
strategy = this.strategies[i];
if(strategy.autoActivate) {
strategy.activate();
}
}
}
},
/**
* Method: removeMap
* The layer has been removed from the map.
*
* Parameters:
* map - {<OpenLayers.Map>}
*/
removeMap: function(map) {
if(this.strategies) {
var strategy, i, len;
for(i=0, len=this.strategies.length; i<len; i++) {
strategy = this.strategies[i];
if(strategy.autoActivate) {
strategy.deactivate();
}
}
}
},
/**
* Method: onMapResize
* Notify the renderer of the change in size.
*
*/
onMapResize: function() {
OpenLayers.Layer.prototype.onMapResize.apply(this, arguments);
this.renderer.setSize(this.map.getSize());
},
/**
* Method: moveTo
* Reset the vector layer's div so that it once again is lined up with
* the map. Notify the renderer of the change of extent, and in the
* case of a change of zoom level (resolution), have the
* renderer redraw features.
*
* If the layer has not yet been drawn, cycle through the layer's
* features and draw each one.
*
* Parameters:
* bounds - {<OpenLayers.Bounds>}
* zoomChanged - {Boolean}
* dragging - {Boolean}
*/
moveTo: function(bounds, zoomChanged, dragging) {
OpenLayers.Layer.prototype.moveTo.apply(this, arguments);
var coordSysUnchanged = true;
if (!dragging) {
this.renderer.root.style.visibility = "hidden";
this.div.style.left = -parseInt(this.map.layerContainerDiv.style.left) + "px";
this.div.style.top = -parseInt(this.map.layerContainerDiv.style.top) + "px";
var extent = this.map.getExtent();
coordSysUnchanged = this.renderer.setExtent(extent, zoomChanged);
this.renderer.root.style.visibility = "visible";
// Force a reflow on gecko based browsers to prevent jump/flicker.
// This seems to happen on only certain configurations; it was originally
// noticed in FF 2.0 and Linux.
if (navigator.userAgent.toLowerCase().indexOf("gecko") != -1) {
this.div.scrollLeft = this.div.scrollLeft;
}
if(!zoomChanged && coordSysUnchanged) {
for(var i in this.unrenderedFeatures) {
var feature = this.unrenderedFeatures[i];
this.drawFeature(feature);
}
}
}
if (!this.drawn || zoomChanged || !coordSysUnchanged) {
this.drawn = true;
var feature;
for(var i=0, len=this.features.length; i<len; i++) {
this.renderer.locked = (i !== (len - 1));
feature = this.features[i];
this.drawFeature(feature);
}
}
},
/**
* APIMethod: display
* Hide or show the Layer
*
* Parameters:
* display - {Boolean}
*/
display: function(display) {
OpenLayers.Layer.prototype.display.apply(this, arguments);
// we need to set the display style of the root in case it is attached
// to a foreign layer
var currentDisplay = this.div.style.display;
if(currentDisplay != this.renderer.root.style.display) {
this.renderer.root.style.display = currentDisplay;
}
},
/**
* APIMethod: addFeatures
* Add Features to the layer.
*
* Parameters:
* features - {Array(<OpenLayers.Feature.Vector>)}
* options - {Object}
*/
addFeatures: function(features, options) {
if (!(features instanceof Array)) {
features = [features];
}
var notify = !options || !options.silent;
if(notify) {
var event = {features: features};
var ret = this.events.triggerEvent("beforefeaturesadded", event);
if(ret === false) {
return;
}
features = event.features;
}
for (var i=0, len=features.length; i<len; i++) {
if (i != (features.length - 1)) {
this.renderer.locked = true;
} else {
this.renderer.locked = false;
}
var feature = features[i];
if (this.geometryType &&
!(feature.geometry instanceof this.geometryType)) {
var throwStr = OpenLayers.i18n('componentShouldBe',
{'geomType':this.geometryType.prototype.CLASS_NAME});
throw throwStr;
}
this.features.push(feature);
//give feature reference to its layer
feature.layer = this;
if (!feature.style && this.style) {
feature.style = OpenLayers.Util.extend({}, this.style);
}
if (notify) {
if(this.events.triggerEvent("beforefeatureadded",
{feature: feature}) === false) {
continue;
};
this.preFeatureInsert(feature);
}
this.drawFeature(feature);
if (notify) {
this.events.triggerEvent("featureadded", {
feature: feature
});
this.onFeatureInsert(feature);
}
}
if(notify) {
this.events.triggerEvent("featuresadded", {features: features});
}
},
/**
* APIMethod: removeFeatures
* Remove features from the layer. This erases any drawn features and
* removes them from the layer's control. The beforefeatureremoved
* and featureremoved events will be triggered for each feature. The
* featuresremoved event will be triggered after all features have
* been removed. To supress event triggering, use the silent option.
*
* Parameters:
* features - {Array(<OpenLayers.Feature.Vector>)} List of features to be
* removed.
* options - {Object} Optional properties for changing behavior of the
* removal.
*
* Valid options:
* silent - {Boolean} Supress event triggering. Default is false.
*/
removeFeatures: function(features, options) {
if(!features || features.length === 0) {
return;
}
if (!(features instanceof Array)) {
features = [features];
}
var notify = !options || !options.silent;
for (var i = features.length - 1; i >= 0; i--) {
// We remain locked so long as we're not at 0
// and the 'next' feature has a geometry. We do the geometry check
// because if all the features after the current one are 'null', we
// won't call eraseGeometry, so we break the 'renderer functions
// will always be called with locked=false *last*' rule. The end result
// is a possible gratiutious unlocking to save a loop through the rest
// of the list checking the remaining features every time. So long as
// null geoms are rare, this is probably okay.
if (i != 0 && features[i-1].geometry) {
this.renderer.locked = true;
} else {
this.renderer.locked = false;
}
var feature = features[i];
delete this.unrenderedFeatures[feature.id];
if (notify) {
this.events.triggerEvent("beforefeatureremoved", {
feature: feature
});
}
this.features = OpenLayers.Util.removeItem(this.features, feature);
// feature has no layer at this point
feature.layer = null;
if (feature.geometry) {
this.renderer.eraseFeatures(feature);
}
//in the case that this feature is one of the selected features,
// remove it from that array as well.
if (OpenLayers.Util.indexOf(this.selectedFeatures, feature) != -1){
OpenLayers.Util.removeItem(this.selectedFeatures, feature);
}
if (notify) {
this.events.triggerEvent("featureremoved", {
feature: feature
});
}
}
if (notify) {
this.events.triggerEvent("featuresremoved", {features: features});
}
},
/**
* APIMethod: destroyFeatures
* Erase and destroy features on the layer.
*
* Parameters:
* features - {Array(<OpenLayers.Feature.Vector>)} An optional array of
* features to destroy. If not supplied, all features on the layer
* will be destroyed.
* options - {Object}
*/
destroyFeatures: function(features, options) {
var all = (features == undefined); // evaluates to true if
// features is null
if(all) {
features = this.features;
}
if(features) {
this.removeFeatures(features, options);
for(var i=features.length-1; i>=0; i--) {
features[i].destroy();
}
}
},
/**
* APIMethod: drawFeature
* Draw (or redraw) a feature on the layer. If the optional style argument
* is included, this style will be used. If no style is included, the
* feature's style will be used. If the feature doesn't have a style,
* the layer's style will be used.
*
* This function is not designed to be used when adding features to
* the layer (use addFeatures instead). It is meant to be used when
* the style of a feature has changed, or in some other way needs to
* visually updated *after* it has already been added to a layer. You
* must add the feature to the layer for most layer-related events to
* happen.
*
* Parameters:
* feature - {<OpenLayers.Feature.Vector>}
* style - {Object} Symbolizer hash or {String} renderIntent
*/
drawFeature: function(feature, style) {
// don't try to draw the feature with the renderer if the layer is not
// drawn itself
if (!this.drawn) {
return
}
if (typeof style != "object") {
if(!style && feature.state === OpenLayers.State.DELETE) {
style = "delete";
}
var renderIntent = style || feature.renderIntent;
style = feature.style || this.style;
if (!style) {
style = this.styleMap.createSymbolizer(feature, renderIntent);
}
}
if (!this.renderer.drawFeature(feature, style)) {
this.unrenderedFeatures[feature.id] = feature;
} else {
delete this.unrenderedFeatures[feature.id];
};
},
/**
* Method: eraseFeatures
* Erase features from the layer.
*
* Parameters:
* features - {Array(<OpenLayers.Feature.Vector>)}
*/
eraseFeatures: function(features) {
this.renderer.eraseFeatures(features);
},
/**
* Method: getFeatureFromEvent
* Given an event, return a feature if the event occurred over one.
* Otherwise, return null.
*
* Parameters:
* evt - {Event}
*
* Returns:
* {<OpenLayers.Feature.Vector>} A feature if one was under the event.
*/
getFeatureFromEvent: function(evt) {
if (!this.renderer) {
OpenLayers.Console.error(OpenLayers.i18n("getFeatureError"));
return null;
}
var featureId = this.renderer.getFeatureIdFromEvent(evt);
return this.getFeatureById(featureId);
},
/**
* APIMethod: getFeatureById
* Given a feature id, return the feature if it exists in the features array
*
* Parameters:
* featureId - {String}
*
* Returns:
* {<OpenLayers.Feature.Vector>} A feature corresponding to the given
* featureId
*/
getFeatureById: function(featureId) {
//TBD - would it be more efficient to use a hash for this.features?
var feature = null;
for(var i=0, len=this.features.length; i<len; ++i) {
if(this.features[i].id == featureId) {
feature = this.features[i];
break;
}
}
return feature;
},
/**
* Unselect the selected features
* i.e. clears the featureSelection array
* change the style back
clearSelection: function() {
var vectorLayer = this.map.vectorLayer;
for (var i = 0; i < this.map.featureSelection.length; i++) {
var featureSelection = this.map.featureSelection[i];
vectorLayer.drawFeature(featureSelection, vectorLayer.style);
}
this.map.featureSelection = [];
},
*/
/**
* APIMethod: onFeatureInsert
* method called after a feature is inserted.
* Does nothing by default. Override this if you
* need to do something on feature updates.
*
* Paarameters:
* feature - {<OpenLayers.Feature.Vector>}
*/
onFeatureInsert: function(feature) {
},
/**
* APIMethod: preFeatureInsert
* method called before a feature is inserted.
* Does nothing by default. Override this if you
* need to do something when features are first added to the
* layer, but before they are drawn, such as adjust the style.
*
* Parameters:
* feature - {<OpenLayers.Feature.Vector>}
*/
preFeatureInsert: function(feature) {
},
/**
* APIMethod: getDataExtent
* Calculates the max extent which includes all of the features.
*
* Returns:
* {<OpenLayers.Bounds>}
*/
getDataExtent: function () {
var maxExtent = null;
if(this.features && (this.features.length > 0)) {
maxExtent = new OpenLayers.Bounds();
for(var i=0, len=this.features.length; i<len; i++) {
maxExtent.extend(this.features[i].geometry.getBounds());
}
}
return maxExtent;
},
CLASS_NAME: "OpenLayers.Layer.Vector"
});