npm-polymer-elements
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Polymer Elements package for npm
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HTML
<!--
Copyright (c) 2015 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="../iron-flex-layout/iron-flex-layout.html">
<!--
`paper-header-panel` contains a header section and a content panel section.
__Important:__ The `paper-header-panel` will not display if its parent does not have a height.
Using layout classes, you can make the `paper-header-panel` fill the screen
<body class="fullbleed layout vertical">
<paper-header-panel class="flex">
<paper-toolbar>
<div>Hello World!</div>
</paper-toolbar>
</paper-header-panel>
</body>
Special support is provided for scrolling modes when one uses a paper-toolbar or equivalent for the
header section.
Example:
<paper-header-panel>
<paper-toolbar>Header</paper-toolbar>
<div>Content goes here...</div>
</paper-header-panel>
If you want to use other than `paper-toolbar` for the header, add `paper-header` class to that
element.
Example:
<paper-header-panel>
<div class="paper-header">Header</div>
<div>Content goes here...</div>
</paper-header-panel>
To have the content fit to the main area, use the `fit` class.
<paper-header-panel>
<div class="paper-header">standard</div>
<div class="fit">content fits 100% below the header</div>
</paper-header-panel>
### Modes
Controls header and scrolling behavior. Options are `standard`, `seamed`, `waterfall`, `waterfall-tall`, `scroll` and
`cover`. Default is `standard`.
Mode | Description
----------------|-------------
`standard` | The header is a step above the panel. The header will consume the panel at the point of entry, preventing it from passing through to the opposite side.
`seamed` | The header is presented as seamed with the panel.
`waterfall` | Similar to standard mode, but header is initially presented as seamed with panel, but then separates to form the step.
`waterfall-tall` | The header is initially taller (`tall` class is added to the header). As the user scrolls, the header separates (forming an edge) while condensing (`tall` class is removed from the header).
`scroll` | The header keeps its seam with the panel, and is pushed off screen.
`cover` | The panel covers the whole `paper-header-panel` including the header. This allows user to style the panel in such a way that the panel is partially covering the header.
Example:
<paper-header-panel mode="waterfall">
<div class="paper-header">standard</div>
<div class="content fit">content fits 100% below the header</div>
</paper-header-panel>
### Styling
To change the shadow that shows up underneath the header:
paper-header-panel {
--paper-header-panel-shadow: {
height: 6px;
bottom: -6px;
box-shadow: inset 0px 5px 6px -3px rgba(0, 0, 0, 0.4);
};
}
To change the panel container in different modes:
paper-header-panel {
--paper-header-panel-standard-container: {
border: 1px solid gray;
};
--paper-header-panel-seamed-container: {
border: 1px solid gray;
};
--paper-header-panel-waterfall-container: {
border: 1px solid gray;
};
--paper-header-panel-waterfall-tall-container: {
border: 1px solid gray;
};
--paper-header-panel-scroll-container: {
border: 1px solid gray;
};
--paper-header-panel-cover-container: {
border: 1px solid gray;
};
}
The following custom properties and mixins are available for styling:
Custom property | Description | Default
----------------|-------------|----------
`--paper-header-panel` | Mixin applied to the element | `{}`
`--paper-header-panel-body` | Mixin applied to the element's body (i.e. everything below the toolbar) | `{}`
`--paper-header-panel-scroll-container` | Mixin applied to the container when in scroll mode | `{}`
`--paper-header-panel-cover-container` | Mixin applied to the container when in cover mode | `{}`
`--paper-header-panel-standard-container` | Mixin applied to the container when in standard mode | `{}`
`--paper-header-panel-seamed-container` | Mixin applied to the container when in seamed mode | `{}`
`--paper-header-panel-waterfall-container` | Mixin applied to the container when in waterfall mode | `{}`
`--paper-header-panel-waterfall-tall-container` | Mixin applied to the container when in tall waterfall mode | `{}`
@group Paper Elements
@element paper-header-panel
@demo demo/index.html
@hero hero.svg
-->
<dom-module id="paper-header-panel">
<template>
<style>
:host {
--paper-header-panel-shadow: {
height: 6px;
bottom: -6px;
box-shadow: inset 0px 5px 6px -3px rgba(0, 0, 0, 0.4);
};
@apply(--layout-vertical);
position: relative;
height: 100%;
@apply(--paper-header-panel);
}
#mainContainer {
@apply(--layout-flex);
position: relative;
overflow-y: auto;
overflow-x: hidden;
-webkit-overflow-scrolling: touch;
}
#mainPanel {
@apply(--layout-vertical);
@apply(--layout-flex);
position: relative;
min-height: 0;
@apply(--paper-header-panel-body);
}
/*
* mode: scroll
*/
:host([mode=scroll]) #mainContainer {
@apply(--paper-header-panel-scroll-container);
overflow: visible;
}
:host([mode=scroll]) {
overflow-y: auto;
overflow-x: hidden;
-webkit-overflow-scrolling: touch;
}
/*
* mode: cover
*/
:host([mode=cover]) #mainContainer {
@apply(--paper-header-panel-cover-container);
position: absolute;
top: 0;
right: 0;
bottom: 0;
left: 0;
}
:host([mode=cover]) #mainPanel {
position: static;
}
/*
* mode: standard
*/
:host([mode=standard]) #mainContainer {
@apply(--paper-header-panel-standard-container);
}
/*
* mode: seamed
*/
:host([mode=seamed]) #mainContainer {
@apply(--paper-header-panel-seamed-container);
}
/*
* mode: waterfall
*/
:host([mode=waterfall]) #mainContainer {
@apply(--paper-header-panel-waterfall-container);
}
/*
* mode: waterfall-tall
*/
:host([mode=waterfall-tall]) #mainContainer {
@apply(--paper-header-panel-waterfall-tall-container);
}
#dropShadow {
@apply(--paper-header-panel-shadow);
position: absolute;
top: 0;
left: 0;
right: 0;
height: 6px;
pointer-events: none;
-webkit-transition: opacity 0.5s;
transition: opacity 0.5s;
opacity: 0;
}
#dropShadow.has-shadow {
opacity: 1;
}
</style>
<content id="headerContent" select="paper-toolbar, .paper-header"></content>
<div id="mainPanel">
<div id="mainContainer" class$="[[_computeMainContainerClass(mode)]]">
<content id="mainContent" select="*"></content>
</div>
<div id="dropShadow"></div>
</div>
</template>
<script>
(function() {
'use strict';
var SHADOW_WHEN_SCROLLING = 1;
var SHADOW_ALWAYS = 2;
var MODE_CONFIGS = {
outerScroll: {
'scroll': true
},
shadowMode: {
'standard': SHADOW_ALWAYS,
'waterfall': SHADOW_WHEN_SCROLLING,
'waterfall-tall': SHADOW_WHEN_SCROLLING
},
tallMode: {
'waterfall-tall': true
}
};
Polymer({
is: 'paper-header-panel',
/**
* Fired when the content has been scrolled. `event.detail.target` returns
* the scrollable element which you can use to access scroll info such as
* `scrollTop`.
*
* <paper-header-panel on-content-scroll="scrollHandler">
* ...
* </paper-header-panel>
*
*
* scrollHandler: function(event) {
* var scroller = event.detail.target;
* console.log(scroller.scrollTop);
* }
*
* @event content-scroll
*/
properties: {
/**
* Controls header and scrolling behavior. Options are
* `standard`, `seamed`, `waterfall`, `waterfall-tall`, `scroll` and
* `cover`. Default is `standard`.
*
* `standard`: The header is a step above the panel. The header will consume the
* panel at the point of entry, preventing it from passing through to the
* opposite side.
*
* `seamed`: The header is presented as seamed with the panel.
*
* `waterfall`: Similar to standard mode, but header is initially presented as
* seamed with panel, but then separates to form the step.
*
* `waterfall-tall`: The header is initially taller (`tall` class is added to
* the header). As the user scrolls, the header separates (forming an edge)
* while condensing (`tall` class is removed from the header).
*
* `scroll`: The header keeps its seam with the panel, and is pushed off screen.
*
* `cover`: The panel covers the whole `paper-header-panel` including the
* header. This allows user to style the panel in such a way that the panel is
* partially covering the header.
*
* <paper-header-panel mode="cover">
* <paper-toolbar class="tall">
* <paper-icon-button icon="menu"></paper-icon-button>
* </paper-toolbar>
* <div class="content"></div>
* </paper-header-panel>
*/
mode: {
type: String,
value: 'standard',
observer: '_modeChanged',
reflectToAttribute: true
},
/**
* If true, the drop-shadow is always shown no matter what mode is set to.
*/
shadow: {
type: Boolean,
value: false
},
/**
* The class used in waterfall-tall mode. Change this if the header
* accepts a different class for toggling height, e.g. "medium-tall"
*/
tallClass: {
type: String,
value: 'tall'
},
/**
* If true, the scroller is at the top
*/
atTop: {
type: Boolean,
value: true,
readOnly: true
}
},
observers: [
'_computeDropShadowHidden(atTop, mode, shadow)'
],
ready: function() {
this.scrollHandler = this._scroll.bind(this);
},
attached: function() {
this._addListener();
// Run `scroll` logic once to initialize class names, etc.
this._keepScrollingState();
},
detached: function() {
this._removeListener();
},
/**
* Returns the header element
*
* @property header
* @type Object
*/
get header() {
return Polymer.dom(this.$.headerContent).getDistributedNodes()[0];
},
/**
* Returns the scrollable element.
*
* @property scroller
* @type Object
*/
get scroller() {
return this._getScrollerForMode(this.mode);
},
/**
* Returns true if the scroller has a visible shadow.
*
* @property visibleShadow
* @type Boolean
*/
get visibleShadow() {
return this.$.dropShadow.classList.contains('has-shadow');
},
_computeDropShadowHidden: function(atTop, mode, shadow) {
var shadowMode = MODE_CONFIGS.shadowMode[mode];
if (this.shadow) {
this.toggleClass('has-shadow', true, this.$.dropShadow);
} else if (shadowMode === SHADOW_ALWAYS) {
this.toggleClass('has-shadow', true, this.$.dropShadow);
} else if (shadowMode === SHADOW_WHEN_SCROLLING && !atTop) {
this.toggleClass('has-shadow', true, this.$.dropShadow);
} else {
this.toggleClass('has-shadow', false, this.$.dropShadow);
}
},
_computeMainContainerClass: function(mode) {
// TODO: It will be useful to have a utility for classes
// e.g. Polymer.Utils.classes({ foo: true });
var classes = {};
classes['flex'] = mode !== 'cover';
return Object.keys(classes).filter(
function(className) {
return classes[className];
}).join(' ');
},
_addListener: function() {
this.scroller.addEventListener('scroll', this.scrollHandler, false);
},
_removeListener: function() {
this.scroller.removeEventListener('scroll', this.scrollHandler);
},
_modeChanged: function(newMode, oldMode) {
var configs = MODE_CONFIGS;
var header = this.header;
var animateDuration = 200;
if (header) {
// in tallMode it may add tallClass to the header; so do the cleanup
// when mode is changed from tallMode to not tallMode
if (configs.tallMode[oldMode] && !configs.tallMode[newMode]) {
header.classList.remove(this.tallClass);
this.async(function() {
header.classList.remove('animate');
}, animateDuration);
} else {
header.classList.toggle('animate', configs.tallMode[newMode]);
}
}
this._keepScrollingState();
},
_keepScrollingState: function() {
var main = this.scroller;
var header = this.header;
this._setAtTop(main.scrollTop === 0);
if (header && this.tallClass && MODE_CONFIGS.tallMode[this.mode]) {
this.toggleClass(this.tallClass, this.atTop ||
header.classList.contains(this.tallClass) &&
main.scrollHeight < this.offsetHeight, header);
}
},
_scroll: function() {
this._keepScrollingState();
this.fire('content-scroll', {target: this.scroller}, {bubbles: false});
},
_getScrollerForMode: function(mode) {
return MODE_CONFIGS.outerScroll[mode] ?
this : this.$.mainContainer;
}
});
})();
</script>
</dom-module>