Import Polymer 0.8 and several key elements.

third_party/polymer/v0_8/components/paper-ripple/paper-ripple.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
+-->
+
+<!--
+`paper-ripple` provides a visual effect that other paper elements can
+use to simulate a rippling effect emanating from the point of contact.  The
+effect can be visualized as a concentric circle with motion.
+
+Example:
+
+    <paper-ripple></paper-ripple>
+
+`paper-ripple` listens to "down" and "up" events so it would display ripple
+effect when touches on it.  You can also defeat the default behavior and
+manually route the down and up actions to the ripple element.  Note that it is
+important if you call downAction() you will have to make sure to call upAction()
+so that `paper-ripple` would end the animation loop.
+
+Example:
+
+    <paper-ripple id="ripple" style="pointer-events: none;"></paper-ripple>
+    ...
+    downAction: function(e) {
+      this.$.ripple.downAction({x: e.x, y: e.y});
+    },
+    upAction: function(e) {
+      this.$.ripple.upAction();
+    }
+
+Styling ripple effect:
+
+  Use CSS color property to style the ripple:
+
+    paper-ripple {
+      color: #4285f4;
+    }
+
+  Note that CSS color property is inherited so it is not required to set it on
+  the `paper-ripple` element directly.
+
+By default, the ripple is centered on the point of contact.  Apply the `recenters`
+attribute to have the ripple grow toward the center of its container.
+
+    <paper-ripple recenters></paper-ripple>
+
+Apply `circle` class to make the rippling effect within a circle.
+
+    <paper-ripple class="circle"></paper-ripple>
+
+@group Paper Elements
+@element paper-ripple
+@homepage github.io
+-->
+
+<!--
+Fired when the animation finishes. This is useful if you want to wait until the ripple
+animation finishes to perform some action.
+
+@event transitionend
+@param {Object} detail
+@param {Object} detail.node The animated node
+-->
+
+<link rel="import" href="../polymer/polymer.html">
+
+<dom-module id="paper-ripple">
+  <style>
+    :host {
+      display: block;
+      position: absolute;
+      border-radius: inherit;
+      overflow: hidden;
+      top: 0;
+      left: 0;
+      right: 0;
+      bottom: 0;
+
+      /* This resolves a rendering issue in Chrome 40 where the
+         ripple is not properly clipped by its parent (which may have
+         rounded corners. See: http://jsbin.com/temexa/4 */
+      -webkit-transform: translate3d(0, 0, 0);
+      transform: translate3d(0, 0, 0);
+    }
+
+    :host([noink]) {
+      pointer-events: none;
+    }
+
+    #background,
+    #waves,
+    .wave-container,
+    .wave {
+      pointer-events: none;
+      position: absolute;
+      top: 0;
+      left: 0;
+      width: 100%;
+      height: 100%;
+    }
+
+    #background,
+    .wave {
+      opacity: 0;
+    }
+
+    #waves,
+    .wave {
+      overflow: hidden;
+    }
+
+    .wave-container,
+    .wave {
+      border-radius: 50%;
+    }
+
+    :host(.circle) #background,
+    :host(.circle) #waves {
+      border-radius: 50%;
+    }
+
+    :host(.circle) .wave-container {
+      overflow: hidden;
+    }
+
+  </style>
+  <template>
+    <div id="background"></div>
+    <div id="waves"></div>
+  </template>
+</dom-module>
+<script>
+  (function() {
+    var Utility = {
+      cssColorWithAlpha: function(cssColor, alpha) {
+        var parts = cssColor.match(/^rgb\((\d+),\s*(\d+),\s*(\d+)\)$/);
+
+        if (typeof alpha == 'undefined') {
+          alpha = 1;
+        }
+
+        if (!parts) {
+          return 'rgba(255, 255, 255, ' + alpha + ')';
+        }
+
+        return 'rgba(' + parts[1] + ', ' + parts[2] + ', ' + parts[3] + ', ' + alpha + ')';
+      },
+
+      distance: function(x1, y1, x2, y2) {
+        var xDelta = (x1 - x2);
+        var yDelta = (y1 - y2);
+
+        return Math.sqrt(xDelta * xDelta + yDelta * yDelta);
+      },
+
+      now: (function() {
+        if (window.performance && window.performance.now) {
+          return window.performance.now.bind(window.performance);
+        }
+
+        return Date.now;
+      })()
+    };
+
+    /**
+     * @param {HTMLElement} element
+     * @constructor
+     */
+    function ElementMetrics(element) {
+      this.element = element;
+      this.width = this.boundingRect.width;
+      this.height = this.boundingRect.height;
+
+      this.size = Math.max(this.width, this.height);
+    }
+
+    ElementMetrics.prototype = {
+      get boundingRect () {
+        return this.element.getBoundingClientRect();
+      },
+
+      furthestCornerDistanceFrom: function(x, y) {
+        var topLeft = Utility.distance(x, y, 0, 0);
+        var topRight = Utility.distance(x, y, this.width, 0);
+        var bottomLeft = Utility.distance(x, y, 0, this.height);
+        var bottomRight = Utility.distance(x, y, this.width, this.height);
+
+        return Math.max(topLeft, topRight, bottomLeft, bottomRight);
+      }
+    };
+
+    /**
+     * @param {HTMLElement} element
+     * @constructor
+     */
+    function Ripple(element) {
+      this.element = element;
+      this.color = window.getComputedStyle(element).color;
+
+      this.wave = document.createElement('div');
+      this.waveContainer = document.createElement('div');
+      this.wave.style.backgroundColor = this.color;
+      this.wave.classList.add('wave');
+      this.waveContainer.classList.add('wave-container');
+      Polymer.dom(this.waveContainer).appendChild(this.wave);
+
+      this.resetInteractionState();
+    }
+
+    Ripple.MAX_RADIUS = 300;
+
+    Ripple.prototype = {
+      get recenters() {
+        return this.element.recenters;
+      },
+
+      get mouseDownElapsed() {
+        var elapsed;
+
+        if (!this.mouseDownStart) {
+          return 0;
+        }
+
+        elapsed = Utility.now() - this.mouseDownStart;
+
+        if (this.mouseUpStart) {
+          elapsed -= this.mouseUpElapsed;
+        }
+
+        return elapsed;
+      },
+
+      get mouseUpElapsed() {
+        return this.mouseUpStart ?
+          Utility.now () - this.mouseUpStart : 0;
+      },
+
+      get mouseDownElapsedSeconds() {
+        return this.mouseDownElapsed / 1000;
+      },
+
+      get mouseUpElapsedSeconds() {
+        return this.mouseUpElapsed / 1000;
+      },
+
+      get mouseInteractionSeconds() {
+        return this.mouseDownElapsedSeconds + this.mouseUpElapsedSeconds;
+      },
+
+      get initialOpacity() {
+        return this.element.initialOpacity;
+      },
+
+      get opacityDecayVelocity() {
+        return this.element.opacityDecayVelocity;
+      },
+
+      get radius() {
+        var width2 = this.containerMetrics.width * this.containerMetrics.width;
+        var height2 = this.containerMetrics.height * this.containerMetrics.height;
+        var waveRadius = Math.min(
+          Math.sqrt(width2 + height2),
+          Ripple.MAX_RADIUS
+        ) * 1.1 + 5;
+
+        var duration = 1.1 - 0.2 * (waveRadius / Ripple.MAX_RADIUS);
+        var timeNow = this.mouseInteractionSeconds / duration;
+        var size = waveRadius * (1 - Math.pow(80, -timeNow));
+
+        return Math.abs(size);
+      },
+
+      get opacity() {
+        if (!this.mouseUpStart) {
+          return this.initialOpacity;
+        }
+
+        return Math.max(
+          0,
+          this.initialOpacity - this.mouseUpElapsedSeconds * this.opacityDecayVelocity
+        );
+      },
+
+      get outerOpacity() {
+        // Linear increase in background opacity, capped at the opacity
+        // of the wavefront (waveOpacity).
+        var outerOpacity = this.mouseUpElapsedSeconds * 0.3;
+        var waveOpacity = this.opacity;
+
+        return Math.max(
+          0,
+          Math.min(outerOpacity, waveOpacity)
+        );
+      },
+
+      get isOpacityFullyDecayed() {
+        return this.opacity < 0.01 &&
+          this.radius >= Math.min(this.maxRadius, Ripple.MAX_RADIUS);
+      },
+
+      get isRestingAtMaxRadius() {
+        return this.opacity >= this.initialOpacity &&
+          this.radius >= Math.min(this.maxRadius, Ripple.MAX_RADIUS);
+      },
+
+      get isAnimationComplete() {
+        return this.mouseUpStart ?
+          this.isOpacityFullyDecayed : this.isRestingAtMaxRadius;
+      },
+
+      get translationFraction() {
+        return Math.min(
+          1,
+          this.radius / this.containerMetrics.size * 2 / Math.sqrt(2)
+        );
+      },
+
+      get xNow() {
+        if (this.xEnd) {
+          return this.xStart + this.translationFraction * (this.xEnd - this.xStart);
+        }
+
+        return this.xStart;
+      },
+
+      get yNow() {
+        if (this.yEnd) {
+          return this.yStart + this.translationFraction * (this.yEnd - this.yStart);
+        }
+
+        return this.yStart;
+      },
+
+      get isMouseDown() {
+        return this.mouseDownStart && !this.mouseUpStart;
+      },
+
+      resetInteractionState: function() {
+        this.maxRadius = 0;
+        this.mouseDownStart = 0;
+        this.mouseUpStart = 0;
+
+        this.xStart = 0;
+        this.yStart = 0;
+        this.xEnd = 0;
+        this.yEnd = 0;
+        this.slideDistance = 0;
+
+        this.containerMetrics = new ElementMetrics(this.element);
+      },
+
+      draw: function() {
+        var scale;
+        var translateString;
+        var dx;
+        var dy;
+
+        this.wave.style.opacity = this.opacity;
+
+        scale = this.radius / (this.containerMetrics.size / 2);
+        dx = this.xNow - (this.containerMetrics.width / 2);
+        dy = this.yNow - (this.containerMetrics.height / 2);
+
+        Polymer.Base.translate3d(this.waveContainer, dx + 'px', dy + 'px', 0);
+
+        // 2d transform for safari because of border-radius and overflow:hidden clipping bug.
+        // https://bugs.webkit.org/show_bug.cgi?id=98538
+        this.wave.style.webkitTransform = 'scale(' + scale + ',' + scale + ')';
+        this.wave.style.transform = 'scale3d(' + scale + ',' + scale + ',1)';
+      },
+
+      mousedownAction: function(event) {
+        this.resetInteractionState();
+        this.mouseDownStart = Utility.now();
+
+        this.xStart = event ?
+          event.x - this.containerMetrics.boundingRect.left :
+          this.containerMetrics.width / 2;
+        this.yStart = event ?
+          event.y - this.containerMetrics.boundingRect.top :
+          this.containerMetrics.height / 2;
+
+        if (this.recenters) {
+          this.xEnd = this.containerMetrics.width / 2;
+          this.yEnd = this.containerMetrics.height / 2;
+          this.slideDistance = Utility.distance(
+            this.xStart, this.yStart, this.xEnd, this.yEnd
+          );
+        }
+
+        this.maxRadius = this.containerMetrics.furthestCornerDistanceFrom(
+          this.xStart,
+          this.yStart
+        );
+
+        this.waveContainer.style.top =
+          (this.containerMetrics.height - this.containerMetrics.size) / 2 + 'px';
+        this.waveContainer.style.left =
+          (this.containerMetrics.width - this.containerMetrics.size) / 2 + 'px';
+
+        this.waveContainer.style.width = this.containerMetrics.size + 'px';
+        this.waveContainer.style.height = this.containerMetrics.size + 'px';
+      },
+
+      mouseupAction: function(event) {
+        if (!this.isMouseDown) {
+          return;
+        }
+
+        this.mouseUpStart = Utility.now();
+      },
+
+      remove: function() {
+        Polymer.dom(this.waveContainer.parentNode).removeChild(
+          this.waveContainer
+        );
+      }
+    };
+
+    Polymer({
+      is: 'paper-ripple',
+
+      properties: {
+        /**
+         * The initial opacity set on the wave.
+         *
+         * @attribute initialOpacity
+         * @type number
+         * @default 0.25
+         */
+        initialOpacity: {
+          type: Number,
+          value: 0.25
+        },
+
+        /**
+         * How fast (opacity per second) the wave fades out.
+         *
+         * @attribute opacityDecayVelocity
+         * @type number
+         * @default 0.8
+         */
+        opacityDecayVelocity: {
+          type: Number,
+          value: 0.8
+        },
+
+        /**
+         * If true, ripples will exhibit a gravitational pull towards
+         * the center of their container as they fade away.
+         *
+         * @attribute recenters
+         * @type boolean
+         * @default false
+         */
+        recenters: {
+          type: Boolean,
+          value: false
+        },
+
+        /**
+         * A list of the visual ripples.
+         *
+         * @attribute ripples
+         * @type Array
+         * @default []
+         */
+        ripples: {
+          type: Array,
+          value: function() {
+            return [];
+          }
+        },
+
+        _animating: {
+          type: Boolean
+        },
+
+        _boundAnimate: {
+          type: Function,
+          value: function() {
+            return this.animate.bind(this);
+          }
+        },
+
+        _boundMousedownAction: {
+          type: Function,
+          value: function() {
+            return this.mousedownAction.bind(this);
+          }
+        },
+
+        _boundMouseupAction: {
+          type: Function,
+          value: function() {
+            return this.mouseupAction.bind(this);
+          }
+        }
+      },
+
+      get target () {
+        return this.host || this.parentNode;
+      },
+
+      attached: function() {
+        this.target.addEventListener('mousedown', this._boundMousedownAction);
+        this.target.addEventListener('mouseup', this._boundMouseupAction);
+      },
+
+      detached: function() {
+        this.target.removeEventListener('mousedown', this._boundMousedownAction);
+        this.target.removeEventListener('mouseup', this._boundMouseupAction);
+      },
+
+      /* TODO(cdata): Replace the above attached / detached listeners when
+         PolymerGestures equivalent lands in 0.8.
+      listeners: {
+        mousedown: 'mousedownAction',
+        mouseup: 'mouseupAction'
+      },
+      */
+
+      get shouldKeepAnimating () {
+        for (var index = 0; index < this.ripples.length; ++index) {
+          if (!this.ripples[index].isAnimationComplete) {
+            return true;
+          }
+        }
+
+        return false;
+      },
+
+      simulatedRipple: function() {
+        this.mousedownAction(null);
+
+        // Please see polymer/polymer#1305
+        this.async(function() {
+          this.mouseupAction();
+        }, 1);
+      },
+
+      mousedownAction: function(event) {
+        var ripple = this.addRipple();
+
+        ripple.mousedownAction(event);
+
+        if (!this._animating) {
+          this.animate();
+        }
+      },
+
+      mouseupAction: function(event) {
+        this.ripples.forEach(function(ripple) {
+          ripple.mouseupAction(event);
+        });
+
+        this.animate();
+      },
+
+      onAnimationComplete: function() {
+        this._animating = false;
+        this.$.background.style.backgroundColor = null;
+        this.fire('transitionend');
+      },
+
+      addRipple: function() {
+        var ripple = new Ripple(this);
+
+        Polymer.dom(this.$.waves).appendChild(ripple.waveContainer);
+        this.$.background.style.backgroundColor = ripple.color;
+        this.ripples.push(ripple);
+
+        return ripple;
+      },
+
+      removeRipple: function(ripple) {
+        var rippleIndex = this.ripples.indexOf(ripple);
+
+        if (rippleIndex < 0) {
+          return;
+        }
+
+        this.ripples.splice(rippleIndex, 1);
+
+        ripple.remove();
+      },
+
+      animate: function() {
+        var index;
+        var ripple;
+
+        this._animating = true;
+
+        for (index = 0; index < this.ripples.length; ++index) {
+          ripple = this.ripples[index];
+
+          ripple.draw();
+
+          this.$.background.style.opacity = ripple.outerOpacity;
+
+          if (ripple.isOpacityFullyDecayed && !ripple.isRestingAtMaxRadius) {
+            this.removeRipple(ripple);
+          }
+        }
+
+        if (this.shouldKeepAnimating) {
+          window.requestAnimationFrame(this._boundAnimate);
+        } else if (this.ripples.length === 0) {
+          this.onAnimationComplete();
+        }
+      }
+    });
+  })();
+</script>
+