<dom-module id="page-list">
<style include="shared-styles"></style>
<style>
iron-list {
height: 500px;
}
</style>
<template>
<neon-animated-pages id="pages" selected="0">
<neon-animatable><paper-button id="list-button" raised on-tap="_onOK" >List</paper-button></neon-animatable>
<neon-animatable>
<iron-list id="list" items="[[data]]" as="item">
<template>
<div>
Name: <span>[[item.name]]</span>
</div>
</template>
</iron-list>
</neon-animatable>
</neon-animated-pages>
</template>
<script>
Polymer({
is: "page-list",
attached: function () {
this.data=[
{
index: 0,
name: "Liz Grimes"
},
{
index: 1,
name: "Frazier Lara"
},
{
index: 2,
name: "Dora Griffith"
}];
this.$.list.fire('resize');
},
behaviors: [
Polymer.NeonAnimatableBehavior
],
properties: {
data: {
type: Array,
notify: true
}
},
_onOK: function (e) {
this.$.pages.selected="1";
}
});
</script>
After pushing the "List" button, the iron list is expected to be totatlly displayed. Unfortunately, the result is a display of one line with "Name:" and nothing else. If I force the selected page to "1", <neon-animated-pages id="pages" selected="1"> which means that on the first resfresh of the browser, the page with the iron list is displayed, the display is correct : three lines with the correct data.
The issue seems to be related to the fact that on startup, the page with the iron list is not yet displayed.
Anybody knows how to solve this ?
Seems to be a known issue https://github.com/PolymerElements/neon-animation/issues/115
Please check my suggested solution on github.
I think you need
this.set('data', [...]);
instead of
this.data=[...];
for Polymer to get notice of data change
The following solution is merely a hack, but if you listen to the iron-resize event on your neon-animatable and then call notifyResize() on any child iron-list elements you should be able to get around this issue until a more sustainable fix can be made to https://github.com/PolymerElements/neon-animation/issues/115
Related
I am trying to do the same basic task as this other question, iron-selector selected={{}} binding with iron-pages selected={{}}, but I believe my case must be different, since I cannot replicate the solution.
I want to have a menu of buttons with iron-selector, and when clicked, the content with iron-pagesshould change.
So I have the actual page about.htm that has 1 webcomponent for the button-menu, called about-buttons.htm and then 1 webcomponent for each page, that should load according to which button is pushed by the user; about-who.htm, about-manifesto and about-team.
My question is:
How can I with this structure of my web components bind my buttons with my pages - and / or why is my current method wrong?
There's a lot of different ways to do a simple data binding like this. My method here is definitely not simple, and it does not work (by clicking buttons, the pages does not change).
So my about.htm looks like this (and this is the page people will visit):
<about-buttons selected="{{who}}">
</about-buttons>
<about-iron-pages attr-for-selected="name" selected="{{who}}" fallback-selection="who">
<about-us name="who">
</about-us>
<about-manifesto name="manifesto">
</about-manifesto>
<about-team name="team">
</about-team>
</about-iron-pages>
My about-buttons.htm looks like this:
<iron-selector
attr-for-selected="name"
selected="{{buttonSelected}}"
fallback-selection="who"
class="f-column f-column_3 f-column_mobile_2">
<button class="f-button-group__button" name="manifesto">Manifesto</button>
<button class="f-button-group__button" name="who">Who we are</button>
<button class="f-button-group__button" name="team">Team</button>
</iron-selector>
With this script:
<script>
Polymer({
is: 'about-buttons',
properties: {
buttonSelected: {
type: String,
notify: true,
value: 'who'
}
}
});
</script>
And here's my version of iron-pages:
<dom-module id="about-iron-pages">
<template>
<style>
:host {
display: block;
}
:host > ::content > :not(.iron-selected) {
display: none !important;
}
</style>
<content>
</content>
</template>
<script>
Polymer({
is: 'about-iron-pages',
behaviors: [
Polymer.IronResizableBehavior,
Polymer.IronSelectableBehavior
],
properties: {
activateEvent: {
type: String,
value: null,
}
},
observers: [
'_selectedPageChanged(selected)'
],
_selectedPageChanged: function(selected, old) {
this.async(this.notifyResize);
}
});
</script>
</dom-module>
As already pointed out, your attribute in <about-buttons selected="..."> does not match the actual property name. For <about-buttons>.buttonSelected, your attribute should be button-selected, and that's the only change to your code needed to get the selector working (plunker):
<about-buttons button-selected="{{who}}" ...>
Perhaps there's more context to your need for <about-buttons> and <about-iron-pages>, but otherwise, if you're only trying to implement a tabbed view, you could just use Polymer's components.
Specifically, <about-buttons> could be replaced by <paper-tabs> and <about-iron-pages> by <iron-pages> (plunker).
My goal is to append an element to existing dom-if dynamically. Problem is that after appending I can see appended element in the DOM three but it never reacts on condition and stays always hidden.
<template>
<template id="domif" is="dom-if" if="[[condition]]" restamp></template>
</template>
ready() {
var el = document.createElement("input");
Polymer.dom(this.$.domif).appendChild(el);
Polymer.dom.flush();
}
Exploring DOM with hardcoded dom-if and input shows that <input /> element is actually not a child of dom-if but lives next to it..
<template>
<template is="dom-if" if="[[condition]]" restamp>
<input />
</template>
</template>
That gave me a clue that I probably should append my element next to dom-if... But now the biggest question is how to say to dom-if that appended element should be rendered if condition is satisfied. Any ideas?
How about adding a span in your dom-if and appending it to that span?
Update after some comments : We need to use this.async for the item to be found. Using the ready-event only works when the condition is true initially. So you could append the element in a conditionChanged-observer - this is a working example :
<dom-module id='my-element1'>
<template>
<template is="dom-if" if="[[condition]]" restamp>
<span id="appendHere"></span>
</template>
</template>
</dom-module>
<script>
Polymer({
is: 'my-element1',
properties: {
condition: {
type: Boolean,
observer: "_conditionChanged"
}
},
_conditionChanged: function(newVal) {
if (newVal) {
this.async(function() {
var el = document.createElement("input");
Polymer.dom(this.$$("#appendHere")).appendChild(el);
Polymer.dom.flush();
});
}
}
});
</script>
Try it here : http://plnkr.co/edit/1IIeM3gSjHIIZ5xpZKa1?p=preview .
A side-effect of using dom-if in this case is that after setting the condition to false, the element disappears completely and gets added on the next condition-change again. So every change before setting the condition to false gets lost. You could work around it by putting the added element somewhere hidden when the condition changes and getting it back later, but I don't think this is a good idea, if the following is an alternative :
The Polymer-team recommends using dom-if only if there is no other way, like hiding the element. So, if it is possible you also could do something like this (condition has to be true to hide the element) :
<dom-module id='my-element1'>
<template>
<span id="appendHere" hidden$="[[condition]]"></span>
</template>
</dom-module>
<script>
Polymer({
is: 'my-element1',
properties: {
condition: Boolean
},
ready: function() {
var el = document.createElement("input");
Polymer.dom(this.$.appendHere).appendChild(el);
Polymer.dom.flush();
}
});
</script>
Try it here :
http://plnkr.co/edit/mCtwqmqtCPaLOUveOqWS?p=preview
The template element itself will not be added to the DOM, this is the reason you can't access it using querySelector or getElementXxx
I have a custom element that utilizes iron-list to display an array of objects. Each item is generated via a template as follows:
<iron-list id="projectList" items="[[projects]]" indexAs="_id" as="projLI" class="layout flex">
<template>
<div>
<paper-material id="itemShadow" animated elevation="1">
<div class="item layout horizontal" onmouseover="hoverOver(this)" onmouseout="hoverOut(this)">
<!-- I use a paper-menu-button to display a list of available actions here -->
<!-- list item object content here such as: [[projLI.desc]] etc. -->
</div>
</paper-material>
</div>
</template>
</iron-list>
What is the best polymer-friendly approach to detect both a tap event on the iron-list item itself (ideally knowing which item was actually tapped via projLI._id), yet also be able to handle the internal paper-menu-button tap events in a different way?
I've eye-balled polymer 1.0's new event listeners (https://www.polymer-project.org/1.0/docs/devguide/events.html), as a possible approach, attempting to listen for different element tap events (as shown in example 1 on that page), but I'm not sure if that will work here. I've also considered possibly using iron-selector somehow around iron-list? Is that doable? I'm not sure that will work either, given that iron-selector would only have one child (i.e. the iron-list element and not it's templated children).
I feel like I'm missing a really easy way to accomplish this. Can someone please show me the light?
Follow the model outlined on lines 154 and 184 of this demo.
https://github.com/PolymerElements/iron-list/blob/master/demo/collapse.html
my-element.html
<iron-list items="[[items]]">
<template>
<my-list-item on-tap="_toggleMe"></my-list-item>
</template>
</iron-list>
...
_toggleMe: function(e) {
console.log(e.model.index);
}
The key is to place the event and listener method (toggleMe() in this case) inside the <template> of the iron-list. This allows the iron-list to register the array index.
I do this by encoding an array index in a list element id, then pulling the id out of a list item event target. Here is an example Polymer element that does this.
<link rel="import" href="../../bower_components/polymer/polymer.html">
<link rel="import" href="../../bower_components/iron-list/iron-list.html">
<dom-module id="list-example">
<style>
:host {
display: block;
}
#list-example {
height: 100px;
}
</style>
<template>
<paper-material animated elevation="1">
<iron-list id="list-example" items="[[data]]">
<template>
<div id="{{index2id(item.index)}}" on-mouseover="onMouseOverItem">{{item.name}}</div>
</template>
</iron-list>
</paper-material>
</template>
</dom-module>
<script>
(function () {
Polymer({
is: 'list-example',
ready: function() {
for(var i = 0; i < this.data.length; i++) {
this.data[i].index = i;
}
},
index2id: function(index) {
return "_" + index;
},
id2index: function(id) {
return Number(id.substr(1));
},
onMouseOverItem: function(e) {
console.log('on-mouseover list item:', this.data[this.id2index(e.target.getAttribute('id'))]);
},
properties: {
data: {
type: Array,
value: [{name: 'A'}, {name: 'B'}, {name: 'C'},
{name: 'D'}, {name: 'E'}, {name: 'F'},
{name: 'G'}, {name: 'H'}, {name: 'I'}]
}
}
});
})();
</script>
I was having a similar issue and solved my problem using <array-selector> as follows:
<iron-list items="{{myarray}}" as="ref">
<template>
<div>
<paper-checkbox on-tap="toggleSelection"></paper-checkbox>
<span>{{ref.name}}</span>
</div>
</template>
</iron-list>
<array-selector id="arrsel" items="{{myarray}}"
selected="{{selectedName}}" toggle></array-selector>
and myarray is an array of objects:
var myarray = [{name: "Alice"}, {name: "Ben"}, ...]
and the function toggleSelection is defined as follows:
toggleSelection: function(e) {
console.log ("Selected index is " + e.model.index);
console.log ("Selected name is " + e.model.ref);
this.$.arrsel.select (e.model.ref);
console.log ("Current selection: ", this.selectedName);
}
The field name ref after e.model.__ is the value of the as attribute of iron-list.
WARNING: The variable e.model is not officially documented on the Polymer 1.0 iron-list doc (https://elements.polymer-project.org/elements/iron-list), however I discovered it during my debugging session. I am assuming that e.model is a public property (the coding style of Polymer uses underscore prefix for private property such as: _scroll_Position) and it is not a candidate for deprecation.
I just solved my issue of here https://groups.google.com/forum/#!topic/polymer-dev/r9IsUKVnLVM. Reading this documentation https://www.polymer-project.org/1.0/docs/devguide/events.html.
I hope it helps you!
Wrap your iron-list with an iron-selector - this allows you get to get the row selected / tapped.
(NB: you might need to remove your custom indexAs="_id" attribute to get the right row index)
<iron-selector attr-for-selected="index" on-tap="_itemSelected">
<iron-list id="projectList" items="[[projects]]" as="projLI" class="fit">
<template>
<div class="layout horizontal center" id="{{index}}">
<!-- your row content here -->
</div>
</template>
</iron-list>
</iron-selector>
Polymer method for row item selected:
_itemSelected: function (e) {
console.log(e.target.id); // selected iron-list row index
}
I am very new to web development and am attempting to learn to use polymer to create a simple webpage. I have created a drop down menu populated by the names in a json file similar to the below example. I cannot understand how to display the data associated with the selected menu item. below is the demo code from the polymer project. I understand this question may seem very simple to some of you. Thank you in advance for your patience and any assistance that may be provided.
<paper-menu-button>
<paper-icon-button icon="menu" noink></paper-icon-button>
<paper-dropdown class="dropdown">
<core-menu class="menu">
<template repeat="{{name in food}}">
<paper-item>{{}}</paper-item>
</template>
</core-menu>
</paper-dropdown>
</paper-menu-button>
there are several ways you can check a menu for user input.
method 1
you can use a EventListener to look for the core-select event. to do that you would give the core-menu a id. i am calling it select.
that would make the function look like
this.$.select.addEventListener('core-select', function () {
// access the value with this.selected
});
method 2
you could also use the declarative approach also using a EventListener but this time as a attribute on-core-select="{{selectAction}}" then the function would look like.
selectAction: function () {
// value would be this.$.select.selected if using the select id on the core-menu
}
method 3
you could also use a attribute changed function to get the value when changed. that method would look like.
<paper-menu-button>
<paper-icon-button icon="menu" noink></paper-icon-button>
<paper-dropdown class="dropdown">
<core-menu class="menu" selected="{{selected}}">
<template repeat="{{name in food}}">
<paper-item>{{}}</paper-item>
</template>
</core-menu>
</paper-dropdown>
</paper-menu-button>
the change would call a function that would look something like
selectedChanged: function () {
// value would be this.selected
}
i also made a plunker showing all 3 in use check console for output when selecting http://plnkr.co/edit/odQwNRLFTzyATodQUNh0?p=preview
edit: all this is assuming you are working inside a custom element. outside a custom element method 1 would still work. method 2 and 3 would require a auto-binding template
I'm very new to Polymer too, but I got tabs working this way (i think it may apply to drop-down too):
In normal web-pages:
<body>
<template is="dom-bind" id="app">
<div class="container">
<div class="menu-area">
<paper-tabs selected="{{selected}}" on-iron-select="_onTabSelected">
<template is="dom-repeat" items="[[items]]">
<paper-tab>[[item.name]]</paper-tab>
</template>
</paper-tabs>
</div>
</div>
</template>
<script>
app._onTabSelected = function (e) {
var selectedIndex = e.srcElement.selected;
var item = this.items[selectedIndex];
document.location = item.uri;
};
app.items = [
{id: 'HOME', name: 'Home', uri: "home.html"},
{id: 'PRODUCTS', name: 'Products', uri: "products.html"},
{id: 'USERS', name: 'Users', uri: "users.html"}
];
</script>
</body>
</html>
When composing new elements:
<link rel="import" href="../../bower_components/polymer/polymer.html">
<link rel="import" href="../../bower_components/paper-tabs/paper-tabs.html">
<link rel="import" href="../../bower_components/paper-tabs/paper-tab.html">
<dom-module id="app-header-menu">
<template>
<div class="container">
<div class="menu-area">
<paper-tabs selected="{{selected}}" on-iron-select="_onTabSelected">
<template is="dom-repeat" items="[[items]]"><paper-tab>[[item.name]]</paper-tab></template>
</paper-tabs>
</div>
</div>
</template>
<script>
Polymer({
is: "app-header-menu",
properties: {
items: {
type: Array,
notify: false,
readOnly: false,
value: [
{id: 'HOME', name: 'Home', uri: "home.html"},
{id: 'PRODUCTS', name: 'Products', uri: "products.html"},
{id: 'USERS', name: 'Users', uri: "users.html"}
]
}
},
_onTabSelected: function (e) {
var selectedIndex = e.srcElement.selected;
var item = this.items[selectedIndex];
document.location = item.uri;
}
});
</script>
</dom-module>
I'm trying to encapsulate a paper-dropdown in a paper-button. To do this, I made a custom element, paper-dropdown-holder:
<polymer-element name="paper-dropdown-holder" extends="paper-button" relative on-tap="{{toggle}}">
<template>
<shadow></shadow>
<content></content>
</template>
<script>
Polymer({
toggle: function() {
if (!this.dropdown) {
this.dropdown = this.querySelector('paper-dropdown');
}
this.dropdown && this.dropdown.toggle();
}
});
</script>
</polymer-element>
and I'm using it in the page like:
<paper-dropdown-holder raised tabindex="0" class="unpadded">
<paper-dropdown class="dropdown" flex>
<core-menu class="menu" selected="0">
<paper-item>Writing</paper-item>
<paper-item>Blog</paper-item>
<paper-item>Art</paper-item>
</core-menu>
</paper-dropdown>
</paper-dropdown-holder>
My problem is deciphering The documentation to figure out how to automatically put the text of the currently-selected menu item into the paper-dropdown-holder.
My first attempt was to just use a standard paper-dropdown-menu, but I couldn't as easily style that like a paper-button. Is there any way to do this that's not (for lack of a better term) hacky? I'd love if the answer would keep to the Polymer philosophies.
Bonus challenge: How do I set default text like "choose section"?
One of awesome things of Polymer is it's open source... that said you could learn how to implement new element based on already existing elements....
If you have a look at paper-dropdown-menu source you could easily make something like it but with paper-button as a "control".
So
The new element should extend core-dropdown-base not
paper-button.
To make that element logically working you could do that with
some help of paper-dropdown-menu by binding (core-overlay-open,
core-activate, core-select) events to the according handlers.
(the actual binding happens in core-dropdown-base in dropdown
getter which called inside attached event listener.
To put them together:
<polymer-element name="paper-dropdown-holder" extends="core-dropdown-base" relative>
<template>
<div>
<paper-button raised on-tap="{{toggle}}">{{selectedItemLabel || label}}</paper-button>
<content></content>
</div>
</template>
<script>
Polymer('paper-dropdown-holder', {
publish: {
label: 'Select an item',
},
selectedItemLabel: '',
overlayListeners: {
'core-overlay-open': 'openAction',
'core-activate': 'activateAction',
'core-select': 'selectAction'
},
activateAction: function(e) {
this.opened = false;
},
selectAction: function(e) {
var detail = e.detail;
if (detail.isSelected) {
this.selectedItemLabel = detail.item.label || detail.item.textContent;
} else {
this.selectedItemLabel = '';
}
}
});
</script>
</polymer-element>
Demo.