Port @ahocevar's drag box control to the new control architecture

src/ol/control/dragbox.js

@@ -0,0 +1,91 @@
+goog.provide('ol.control.DragBox');
+
+goog.require('goog.asserts');
+goog.require('goog.dom');
+goog.require('goog.dom.TagName');
+goog.require('goog.events');
+goog.require('goog.style');
+goog.require('ol.Size');
+goog.require('ol.control.Control');
+
+
+/**
+ * @typedef {{map: (ol.Map|undefined),
+ *            startCoordinate: ol.Coordinate}}
+ */
+ol.control.DragBoxOptions;
+
+
+
+/**
+ * @constructor
+ * @extends {ol.control.Control}
+ * @param {ol.control.DragBoxOptions} dragBoxOptions Drag box options.
+ */
+ol.control.DragBox = function(dragBoxOptions) {
+
+  var element = goog.dom.createDom(goog.dom.TagName.DIV, 'ol-dragbox');
+
+  /**
+   * @type {ol.Pixel|undefined}
+   * @private
+   */
+  this.startPixel_ = null;
+
+  /**
+   * @private
+   * @type {ol.Coordinate}
+   */
+  this.startCoordinate_ = dragBoxOptions.startCoordinate;
+
+  /**
+   * @private
+   * @type {?number}
+   */
+  this.dragListenKey_ = null;
+
+  goog.base(this, {
+    element: element,
+    map: dragBoxOptions.map
+  });
+
+};
+goog.inherits(ol.control.DragBox, ol.control.Control);
+
+
+/**
+ * @inheritDoc
+ */
+ol.control.DragBox.prototype.setMap = function(map) {
+  if (!goog.isNull(this.dragListenKey_)) {
+    goog.events.unlistenByKey(this.dragListenKey_);
+    this.dragListenKey_ = null;
+  }
+  if (!goog.isNull(map)) {
+    this.startPixel_ = map.getPixelFromCoordinate(this.startCoordinate_);
+    goog.asserts.assert(goog.isDef(this.startPixel_));
+    goog.style.setPosition(this.element, this.startPixel_);
+    goog.style.setBorderBoxSize(this.element, new ol.Size(0, 0));
+    this.dragListenKey_ = goog.events.listen(
+        map, ol.MapBrowserEvent.EventType.DRAG, this.updateBox_, false, this);
+  }
+  goog.base(this, 'setMap', map);
+};
+
+
+/**
+ * @param {ol.MapBrowserEvent} mapBrowserEvent The event to handle.
+ * @private
+ */
+ol.control.DragBox.prototype.updateBox_ = function(mapBrowserEvent) {
+  var map = this.getMap();
+  var coordinate = mapBrowserEvent.getCoordinate();
+  goog.asserts.assert(goog.isDef(coordinate));
+  var currentPixel = map.getPixelFromCoordinate(coordinate);
+  goog.style.setPosition(this.element, new ol.Pixel(
+      Math.min(currentPixel.x, this.startPixel_.x),
+      Math.min(currentPixel.y, this.startPixel_.y)));
+  goog.style.setBorderBoxSize(this.element, new ol.Size(
+      Math.abs(currentPixel.x - this.startPixel_.x),
+      Math.abs(currentPixel.y - this.startPixel_.y)));
+};