Polymer elements added to third_party/polymer.

third_party/polymer/components/core-drag-drop/core-drag-drop.html

+<!--
+Copyright (c) 2014 The Polymer Project Authors. All rights reserved.
+This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
+The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
+The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
+Code distributed by Google as part of the polymer project is also
+subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
+-->
+
+<link rel="import" href="../polymer/polymer.html">
+
+<style>
+  core-drag-avatar {
+    position: fixed;
+    left: 0;
+    top: 0;
+    display: block;
+    pointer-events: none;
+  }
+</style>
+
+<!--
+@group Polymer Core Elements
+@element core-drag-drop
+@homepage github.io
+-->
+
+<polymer-element name="core-drag-drop">
+<script>
+
+  Polymer('core-drag-drop', {
+
+    observe: {
+      'x y': 'coordinatesChanged'
+    },
+
+    ready: function() {
+      if (!this.__proto__.avatar) {
+        this.__proto__.avatar = document.createElement('core-drag-avatar');
+        document.body.appendChild(this.avatar);
+      }
+      this.dragging = false;
+    },
+
+    draggingChanged: function() {
+      this.avatar.style.display = this.dragging ? '' : 'none';
+    },
+
+    coordinatesChanged: function() {
+      var x = this.x, y = this.y;
+      this.avatar.style.transform = 
+        this.avatar.style.webkitTransform = 
+          'translate(' + x + 'px, ' + y + 'px)';
+    },
+
+    attached: function() {
+      var listen = function(event, handler) {
+        Polymer.addEventListener(this.parentNode, event, this[handler].bind(this));
+      }.bind(this);
+      //
+      listen('trackstart', 'trackStart');
+      listen('track', 'track');
+      listen('trackend', 'trackEnd');
+      //
+      var host = this.parentNode.host || this.parentNode;
+      host.style.cssText += '; user-select: none; -webkit-user-select: none; -moz-user-select: none; -ms-user-select: none;';
+    },
+
+    trackStart: function(event) {
+      this.avatar.style.cssText = '';
+      this.dragInfo = {
+        event: event,
+        avatar: this.avatar
+      };
+      this.fire('drag-start', this.dragInfo);
+      // flaw #1: what if user doesn't need `drag()`?
+      this.dragging = Boolean(this.dragInfo.drag);
+    },
+
+    track: function(event) {
+      if (this.dragging) {
+        this.x = event.pageX;
+        this.y = event.pageY;
+        this.dragInfo.event = event;
+        this.dragInfo.p = {x : this.x, y: this.y};
+        this.dragInfo.drag(this.dragInfo);
+      }
+    },
+
+    trackEnd: function(event) {
+      if (this.dragging) {
+        this.dragging = false;
+        if (this.dragInfo.drop) {
+          this.dragInfo.framed = this.framed(event.relatedTarget);
+          this.dragInfo.event = event;
+          this.dragInfo.drop(this.dragInfo);
+        }
+      }
+      this.dragInfo = null;
+    },
+
+    framed: function(node) {
+      var local = node.getBoundingClientRect();
+      return {x: this.x - local.left, y: this.y - local.top};
+    }
+
+  });
+
+</script>
+</polymer-element>