javascript - 矢量特征渲染

Question

在 OpenLayers 中，我有一个 LineFeature 对象。

我更改对象的样式(例如 my_line.style.StrokeColor="Black")。

但是在我放大/缩小(即重新渲染)之前，屏幕上的颜色不会改变。

如何判断需要重新渲染的矢量特征？

Answer 1

更改样式后，尝试在包含该要素的矢量图层上调用 redraw() 方法。

更新:如果不想重绘整个图层，您可以尝试drawFeature()方法。如果您查看它的代码，您可能会更好地了解它是如何工作的:

/**
     * 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 - {String | Object} Named render intent or full symbolizer object.
     */
    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);
            }
        }

        var drawn = this.renderer.drawFeature(feature, style);
        //TODO remove the check for null when we get rid of Renderer.SVG
        if (drawn === false || drawn === null) {
            this.unrenderedFeatures[feature.id] = feature;
        } else {
            delete this.unrenderedFeatures[feature.id];
        };
    }