Polymer elements added to third_party/polymer.

third_party/polymer/components/core-overlay/core-overlay.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">
+<link rel="import" href="../core-transition/core-transition.html">
+<link rel="import" href="core-key-helper.html">
+<link rel="import" href="core-overlay-layer.html">
+
+<!--
+The `core-overlay` element displays overlayed on top of other content. It starts
+out hidden and is displayed by setting its `opened` property to true.
+A `core-overlay's` opened state can be toggled by calling the `toggle`
+method.
+
+The `core-overlay` will, by default, show/hide itself when it's opened. The 
+`target` property may be set to another element to cause that element to 
+be shown when the overlay is opened.
+
+It's common to want a `core-overlay` to animate to its opened
+position. The `core-overlay` element uses a `core-transition` to handle
+animation. The default transition is `core-transition-fade` which 
+causes the overlay to fade in when displayed. See 
+<a href="../core-transition/">`core-transition`</a> for more
+information about customizing a `core-overlay's` opening animation. The
+`backdrop` property can be set to true to show a backdrop behind the overlay
+that will darken the rest of the window.
+
+An element that should close the `core-overlay` will automatically
+do so if it's given the `core-overlay-toggle` attribute. This attribute
+can be customized with the `closeAttribute` property. You can also use
+`closeSelector` if more general matching is needed.
+
+By default  `core-overlay` will close whenever the user taps outside it or
+presses the escape key. This behavior can be turned off via the
+`autoCloseDisabled` property.
+
+    <core-overlay>
+      <h2>Dialog</h2>
+      <input placeholder="say something..." autofocus>
+      <div>I agree with this wholeheartedly.</div>
+      <button core-overlay-toggle>OK</button>
+    </core-overlay>
+
+`core-overlay` will automatically size and position itself according to the 
+following rules. If the target's style.top and style.left are unset, the 
+target will be centered. The size of the target is constrained to be no larger
+than the window dimensions. The `margin` property specifies the extra amount
+of space that should be reserved around the overlay. This can be used to ensure
+that, for example, a drop shadow is always visible around the overlay.
+
+@group Core Elements
+@element core-overlay
+@homepage github.io
+-->
+<!--
+Fired when the `core-overlay`'s `opened` property changes.
+
+@event core-overlay-open
+@param {Object} detail
+@param {Object} detail.opened the opened state
+-->
+
+<style>
+  .core-overlay-backdrop {
+    position: fixed;
+    top: 0;
+    left: 0;
+    width: 100vw;
+    height: 100vh;
+    background-color: black;
+    opacity: 0;
+    transition: opacity 0.2s;
+  }
+
+  .core-overlay-backdrop.core-opened {
+    opacity: 0.6;
+  }
+</style>
+
+<polymer-element name="core-overlay">
+<script>
+(function() {
+
+  Polymer('core-overlay', {
+
+    publish: {
+      /**
+       * The target element that will be shown when the overlay is 
+       * opened. If unspecified, the core-overlay itself is the target.
+       *
+       * @attribute target
+       * @type Object
+       * @default the overlay element
+       */
+      target: null,
+
+
+      /**
+       * A `core-overlay`'s size is guaranteed to be 
+       * constrained to the window size. To achieve this, the sizingElement
+       * is sized with a max-height/width. By default this element is the 
+       * target element, but it can be specifically set to a specific element
+       * inside the target if that is more appropriate. This is useful, for 
+       * example, when a region inside the overlay should scroll if needed.
+       *
+       * @attribute sizingTarget
+       * @type Object
+       * @default the target element
+       */
+      sizingTarget: null,
+    
+      /**
+       * Set opened to true to show an overlay and to false to hide it.
+       * A `core-overlay` may be made initially opened by setting its
+       * `opened` attribute.
+       * @attribute opened
+       * @type boolean
+       * @default false
+       */
+      opened: false,
+
+      /**
+       * If true, the overlay has a backdrop darkening the rest of the screen.
+       * The backdrop element is attached to the document body and may be styled
+       * with the class `core-overlay-backdrop`. When opened the `core-opened`
+       * class is applied.
+       *
+       * @attribute backdrop
+       * @type boolean
+       * @default false
+       */    
+      backdrop: false,
+
+      /**
+       * If true, the overlay is guaranteed to display above page content.
+       *
+       * @attribute layered
+       * @type boolean
+       * @default false
+      */
+      layered: false,
+    
+      /**
+       * By default an overlay will close automatically if the user
+       * taps outside it or presses the escape key. Disable this
+       * behavior by setting the `autoCloseDisabled` property to true.
+       * @attribute autoCloseDisabled
+       * @type boolean
+       * @default false
+       */
+      autoCloseDisabled: false,
+
+      /**
+       * This property specifies an attribute on elements that should
+       * close the overlay on tap. Should not set `closeSelector` if this
+       * is set.
+       *
+       * @attribute closeAttribute
+       * @type string
+       * @default "core-overlay-toggle"
+       */
+      closeAttribute: 'core-overlay-toggle',
+
+      /**
+       * This property specifies a selector matching elements that should
+       * close the overlay on tap. Should not set `closeAttribute` if this
+       * is set.
+       *
+       * @attribute closeSelector
+       * @type string
+       * @default ""
+       */
+      closeSelector: '',
+
+      /**
+       * A `core-overlay` target's size is constrained to the window size.
+       * The `margin` property specifies a pixel amount around the overlay 
+       * that will be reserved. It's useful for ensuring that, for example, 
+       * a shadow displayed outside the target will always be visible.
+       *
+       * @attribute margin
+       * @type number
+       * @default 0
+       */
+      margin: 0,
+
+      /**
+       * The transition property specifies a string which identifies a 
+       * <a href="../core-transition/">`core-transition`</a> element that 
+       * will be used to help the overlay open and close. The default
+       * `core-transition-fade` will cause the overlay to fade in and out.
+       *
+       * @attribute transition
+       * @type string
+       * @default 'core-transition-fade'
+       */
+      transition: 'core-transition-fade'
+
+    },
+
+    captureEventName: 'tap',
+    targetListeners: {
+      'tap': 'tapHandler',
+      'keydown': 'keydownHandler',
+      'core-transitionend': 'transitionend'
+    },
+    
+    registerCallback: function(element) {
+      this.layer = document.createElement('core-overlay-layer');
+      this.keyHelper = document.createElement('core-key-helper');
+      this.meta = document.createElement('core-transition');
+      this.scrim = document.createElement('div');
+      this.scrim.className = 'core-overlay-backdrop';
+    },
+
+    ready: function() {
+      this.target = this.target || this;
+      // flush to ensure styles are installed before paint
+      Platform.flush();
+    },
+
+    /** 
+     * Toggle the opened state of the overlay.
+     * @method toggle
+     */
+    toggle: function() {
+      this.opened = !this.opened;
+    },
+
+    /** 
+     * Open the overlay. This is equivalent to setting the `opened`
+     * property to true.
+     * @method open
+     */
+    open: function() {
+      this.opened = true;
+    },
+
+    /** 
+     * Close the overlay. This is equivalent to setting the `opened` 
+     * property to false.
+     * @method close
+     */
+    close: function() {
+      this.opened = false;
+    },
+
+    domReady: function() {
+      this.ensureTargetSetup();
+    },
+
+    targetChanged: function(old) {
+      if (this.target) {
+        // really make sure tabIndex is set
+        if (this.target.tabIndex < 0) {
+          this.target.tabIndex = -1;
+        }
+        this.addElementListenerList(this.target, this.targetListeners);
+        this.target.style.display = 'none';
+      }
+      if (old) {
+        this.removeElementListenerList(old, this.targetListeners);
+        var transition = this.getTransition();
+        if (transition) {
+          transition.teardown(old);
+        } else {
+          old.style.position = '';
+          old.style.outline = '';
+        }
+        old.style.display = '';
+      }
+    },
+
+    // NOTE: wait to call this until we're as sure as possible that target
+    // is styled.
+    ensureTargetSetup: function() {
+      if (!this.target || this.target.__overlaySetup) {
+        return;
+      }
+      this.target.__overlaySetup = true;
+      this.target.style.display = '';
+      var transition = this.getTransition();
+      if (transition) {
+        transition.setup(this.target);
+      }
+      var computed = getComputedStyle(this.target);
+      this.targetStyle = {
+        position: computed.position === 'static' ? 'fixed' :
+            computed.position
+      }
+      if (!transition) {
+        this.target.style.position = this.targetStyle.position;
+        this.target.style.outline = 'none';
+      }
+      this.target.style.display = 'none';
+    },
+
+    openedChanged: function() {
+      this.transitioning = true;
+      this.ensureTargetSetup();
+      this.prepareRenderOpened();
+      // continue styling after delay so display state can change
+      // without aborting transitions
+      // note: we wait a full frame so that transition changes executed
+      // during measuring do not cause transition
+      this.async(function() {
+        this.target.style.display = '';
+        this.async('renderOpened');
+      });
+      this.fire('core-overlay-open', this.opened);
+    },
+
+    // tasks which must occur before opening; e.g. making the element visible
+    prepareRenderOpened: function() {
+      if (this.opened) {
+        addOverlay(this);
+      }
+      this.prepareBackdrop();
+      // async so we don't auto-close immediately via a click.
+      this.async(function() {
+        if (!this.autoCloseDisabled) {
+          this.enableElementListener(this.opened, document,
+              this.captureEventName, 'captureHandler', true);
+        }
+      });
+      this.enableElementListener(this.opened, window, 'resize',
+          'resizeHandler');
+
+      if (this.opened) {
+        // TODO(sorvell): force SD Polyfill to render
+        forcePolyfillRender(this.target);
+        if (!this._shouldPosition) {
+          this.target.style.position = 'absolute';
+          var computed = getComputedStyle(this.target);
+          var t = (computed.top === 'auto' && computed.bottom === 'auto');
+          var l = (computed.left === 'auto' && computed.right === 'auto');
+          this.target.style.position = this.targetStyle.position;
+          this._shouldPosition = {top: t, left: l};
+        }
+        // if we are showing, then take care when measuring
+        this.prepareMeasure(this.target);
+        this.updateTargetDimensions();
+        this.finishMeasure(this.target);
+        if (this.layered) {
+          this.layer.addElement(this.target);
+          this.layer.opened = this.opened;
+        }
+      }
+    },
+
+    // tasks which cause the overlay to actually open; typically play an
+    // animation
+    renderOpened: function() {
+      var transition = this.getTransition();
+      if (transition) {
+        transition.go(this.target, {opened: this.opened});
+      } else {
+        this.transitionend();
+      }
+      this.renderBackdropOpened();
+    },
+
+    // finishing tasks; typically called via a transition
+    transitionend: function(e) {
+      // make sure this is our transition event.
+      if (e && e.target !== this.target) {
+        return;
+      }
+      this.transitioning = false;
+      if (!this.opened) {
+        this.resetTargetDimensions();
+        this.target.style.display = 'none';
+        this.completeBackdrop();
+        removeOverlay(this);
+        if (this.layered) {
+          if (!currentOverlay()) {
+            this.layer.opened = this.opened;
+          }
+          this.layer.removeElement(this.target);
+        }
+      }
+      this.applyFocus();
+    },
+
+    prepareBackdrop: function() {
+      if (this.backdrop && this.opened) {
+        if (!this.scrim.parentNode) {
+          document.body.appendChild(this.scrim);
+          this.scrim.style.zIndex = currentOverlayZ() - 1;
+        }
+        trackBackdrop(this);
+      }
+    },
+
+    renderBackdropOpened: function() {
+      if (this.backdrop && getBackdrops().length < 2) {
+        this.scrim.classList.toggle('core-opened', this.opened);
+      }
+    },
+
+    completeBackdrop: function() {
+      if (this.backdrop) {
+        trackBackdrop(this);
+        if (getBackdrops().length === 0) {
+          this.scrim.parentNode.removeChild(this.scrim);
+        }
+      }
+    },
+
+    prepareMeasure: function(target) {
+      target.style.transition = target.style.webkitTransition = 'none';
+      target.style.transform = target.style.webkitTransform = 'none';
+      target.style.display = '';
+    },
+
+    finishMeasure: function(target) {
+      target.style.display = 'none';
+      target.style.transform = target.style.webkitTransform = '';
+      target.style.transition = target.style.webkitTransition = '';
+    },
+
+    getTransition: function() {
+      return this.meta.byId(this.transition);
+    },
+
+    getFocusNode: function() {
+      return this.target.querySelector('[autofocus]') || this.target;
+    },
+
+    applyFocus: function() {
+      var focusNode = this.getFocusNode();
+      if (this.opened) {
+        focusNode.focus();
+      } else {
+        focusNode.blur();
+        if (currentOverlay() == this) {
+          console.warn('Current core-overlay is attempting to focus itself as next! (bug)');
+        } else {
+          focusOverlay();
+        }
+      }
+    },
+
+    updateTargetDimensions: function() {
+      this.positionTarget();
+      this.sizeTarget();
+      //
+      if (this.layered) {
+        var rect = this.target.getBoundingClientRect();
+        this.target.style.top = rect.top + 'px';
+        this.target.style.left = rect.left + 'px';
+        this.target.style.right = this.target.style.bottom = 'auto';
+      }
+    },
+
+    sizeTarget: function() {
+      var sizer = this.sizingTarget || this.target;
+      var rect = sizer.getBoundingClientRect();
+      var mt = rect.top === this.margin ? this.margin : this.margin * 2;
+      var ml = rect.left === this.margin ? this.margin : this.margin * 2;
+      var h = window.innerHeight - rect.top - mt;
+      var w = window.innerWidth - rect.left - ml;
+      sizer.style.maxHeight = h + 'px';
+      sizer.style.maxWidth = w + 'px';
+      sizer.style.boxSizing = 'border-box';
+    },
+
+    positionTarget: function() {
+      // vertically and horizontally center if not positioned
+      if (this._shouldPosition.top) {
+        var t = Math.max((window.innerHeight - 
+            this.target.offsetHeight - this.margin*2) / 2, this.margin);
+        this.target.style.top = t + 'px';
+      }
+      if (this._shouldPosition.left) {
+        var l = Math.max((window.innerWidth - 
+            this.target.offsetWidth - this.margin*2) / 2, this.margin);
+        this.target.style.left = l + 'px';
+      }
+    },
+
+    resetTargetDimensions: function() {
+      this.target.style.top = this.target.style.left = '';
+      this.target.style.right = this.target.style.bottom = '';
+      this.target.style.width = this.target.style.height = '';
+      this._shouldPosition = null;
+    },
+
+    tapHandler: function(e) {
+      // closeSelector takes precedence since closeAttribute has a default non-null value.
+      if (e.target &&
+          (this.closeSelector && e.target.matches(this.closeSelector)) ||
+          (this.closeAttribute && e.target.hasAttribute(this.closeAttribute))) {
+        this.toggle();
+      } else {
+        if (this.autoCloseJob) {
+          this.autoCloseJob.stop();
+          this.autoCloseJob = null;
+        }
+      }
+    },
+    
+    // We use the traditional approach of capturing events on document
+    // to to determine if the overlay needs to close. However, due to 
+    // ShadowDOM event retargeting, the event target is not useful. Instead
+    // of using it, we attempt to close asynchronously and prevent the close
+    // if a tap event is immediately heard on the target.
+    // TODO(sorvell): This approach will not work with modal. For
+    // this we need a scrim.
+    captureHandler: function(e) {
+      if (!this.autoCloseDisabled && (currentOverlay() == this)) {
+        this.autoCloseJob = this.job(this.autoCloseJob, function() {
+          this.close();
+        });
+      }
+    },
+
+    keydownHandler: function(e) {
+      if (!this.autoCloseDisabled && (e.keyCode == this.keyHelper.ESCAPE_KEY)) {
+        this.close();
+        e.stopPropagation();
+      }
+    },
+
+    /**
+     * Extensions of core-overlay should implement the `resizeHandler`
+     * method to adjust the size and position of the overlay when the 
+     * browser window resizes.
+     * @method resizeHandler
+     */
+    resizeHandler: function() {
+      this.updateTargetDimensions();
+    },
+
+    // TODO(sorvell): these utility methods should not be here.
+    addElementListenerList: function(node, events) {
+      for (var i in events) {
+        this.addElementListener(node, i, events[i]);
+      }
+    },
+
+    removeElementListenerList: function(node, events) {
+      for (var i in events) {
+        this.removeElementListener(node, i, events[i]);
+      }
+    },
+
+    enableElementListener: function(enable, node, event, methodName, capture) {
+      if (enable) {
+        this.addElementListener(node, event, methodName, capture);
+      } else {
+        this.removeElementListener(node, event, methodName, capture);
+      }
+    },
+
+    addElementListener: function(node, event, methodName, capture) {
+      var fn = this._makeBoundListener(methodName);
+      if (node && fn) {
+        Polymer.addEventListener(node, event, fn, capture);
+      }
+    },
+
+    removeElementListener: function(node, event, methodName, capture) {
+      var fn = this._makeBoundListener(methodName);
+      if (node && fn) {
+        Polymer.removeEventListener(node, event, fn, capture);
+      }
+    },
+
+    _makeBoundListener: function(methodName) {
+      var self = this, method = this[methodName];
+      if (!method) {
+        return;
+      }
+      var bound = '_bound' + methodName;
+      if (!this[bound]) {
+        this[bound] = function(e) {
+          method.call(self, e);
+        }
+      }
+      return this[bound];
+    },
+  });
+
+  function forcePolyfillRender(target) {
+    if (window.ShadowDOMPolyfill) {
+      target.offsetHeight;
+    }
+  }
+
+  // TODO(sorvell): This should be an element with private state so it can
+  // be independent of overlay.
+  // track overlays for z-index and focus managemant
+  var overlays = [];
+  function addOverlay(overlay) {
+    var z0 = currentOverlayZ();
+    overlays.push(overlay);
+    var z1 = currentOverlayZ();
+    if (z1 <= z0) {
+      applyOverlayZ(overlay, z0);
+    }
+  }
+
+  function removeOverlay(overlay) {
+    var i = overlays.indexOf(overlay);
+    if (i >= 0) {
+      overlays.splice(i, 1);
+      setZ(overlay, '');
+    }
+  }
+  
+  function applyOverlayZ(overlay, aboveZ) {
+    setZ(overlay.target, aboveZ + 2);
+  }
+  
+  function setZ(element, z) {
+    element.style.zIndex = z;
+  }
+
+  function currentOverlay() {
+    return overlays[overlays.length-1];
+  }
+  
+  var DEFAULT_Z = 10;
+  
+  function currentOverlayZ() {
+    var z;
+    var current = currentOverlay();
+    if (current) {
+      var z1 = window.getComputedStyle(current.target).zIndex;
+      if (!isNaN(z1)) {
+        z = Number(z1);
+      }
+    }
+    return z || DEFAULT_Z;
+  }
+  
+  function focusOverlay() {
+    var current = currentOverlay();
+    // We have to be careful to focus the next overlay _after_ any current
+    // transitions are complete (due to the state being toggled prior to the
+    // transition). Otherwise, we risk infinite recursion when a transitioning
+    // (closed) overlay becomes the current overlay.
+    //
+    // NOTE: We make the assumption that any overlay that completes a transition
+    // will call into focusOverlay to kick the process back off. Currently:
+    // transitionend -> applyFocus -> focusOverlay.
+    if (current && !current.transitioning) {
+      current.applyFocus();
+    }
+  }
+
+  var backdrops = [];
+  function trackBackdrop(element) {
+    if (element.opened) {
+      backdrops.push(element);
+    } else {
+      var i = backdrops.indexOf(element);
+      if (i >= 0) {
+        backdrops.splice(i, 1);
+      }
+    }
+  }
+
+  function getBackdrops() {
+    return backdrops;
+  }
+})();
+</script>
+</polymer-element>