How do I clear Polymer paper-input? - polymer

I've been toying with Polymer, and a simple app that takes input from a paper-input element, and put it in a list.
I just updated with bower update, and now I can't seem to clear the input field.
This is my code:
<link rel="import" href="../bower_components/polymer/polymer.html">
<polymer-element name="input-reason">
<template>
<content select="paper-input" on-change="{{valueChanged}}"></content>
</template>
<script>
Polymer('input-reason', {
valueChanged: function() {
var inputText = this.getElementsByTagName('paper-input')[0].value;
console.log(inputText);
this.getElementsByTagName('paper-input')[0].value = "";
}
});
</script>
</polymer-element>
This worked before I updated, now nothing happens.
I'm guessing something changed in either paper-input or core-input, but I don't really have an idea what it could be.
Another thing, I'm wondering if it's really necessary to jump through hoops like that to get and set the value of paper-input. It looks so crude.

You can still use inputValue and commit to notify the changes:
<link rel="import" href="../bower_components/polymer/polymer.html">
<polymer-element name="input-reason">
<template>
<content select="paper-input" inputValue="{{ value }}" on-change="{{ valueChanged }}"></content>
</template>
<script>
Polymer('input-reason', {
valueChanged: function () {
var input = this.getElementsByTagName('paper-input')[0];
var inputText = input.inputValue;
console.log(inputText);
input.inputValue = 'sd';
input.commit();
}
});
</script>
</polymer-element>

Related

how to pass data from host element to child element

Having trouble getting my data to work across elements. Say I have an object "records" in my host element. It is usable in that element no problem. But when I try to spin off the view into a separate element, it no longer works.
Here's an example snippet of code. The .template part works fine but I'm not able to replicate the functionality in the child element .my-list. When I try, nothing happens.
<dom-module id="host-element">
...
<template is="dom-repeat" items="{{records}}">
<p>{{item.userName}} - {{item.number}}</p>
</template>
<my-list></my-list>
<script>
Polymer({
is: 'host-element',
ready: function() {
this.records = [
{userName: 'Bob'},
{userName: 'Sally'}
];
}
});
</script>
</dom-module>
If I try simply taking the current .template code and placing it into .my-list, it doesn't work.
I assume I need someway to bind the data into the child element, but I'm not able to figure this out. Adding a: record="{{records}}" to the tag, and then using that in the child element didn't work.
Imagine this is pretty simple, just can't find the answer in the documentation.
It's important that each element's top-level template is a plain template (not is="dom-repeat" or other specialization), otherwise, it should be straightforward:
<link rel="import" href="//polygit.org/components/polymer/polymer.html">
<i>(Requires Chrome)</i>
<host-element></host-element>
<dom-module id="my-list">
<template>
<template is="dom-repeat" items="{{records}}">
<p>{{item.userName}} - {{item.number}}</p>
</template>
</template>
<script>
Polymer({
is: 'my-list'
});
</script>
</dom-module>
<dom-module id="host-element">
<template>
<my-list records="{{records}}"></my-list>
</template>
<script>
Polymer({
is: 'host-element',
ready: function() {
this.records = [{userName: 'Bob'}, {userName: 'Sally'}];
}
});
</script>
</dom-module>

Polymer 1.0 Extending Elements - paper-dialog with custom element

I am am trying to create a custom element that plays a youtube video in paper-dialog. So videoPlayer = Polymer.dom(this.root).querySelector('video-player'); inherits/has access to that paper-dialogs open method, I am trying to extend my custom element. It isn't working, but hopefully I am on the right track and someone can show me correctly.
I am using Polymer 1.0, but I only have https://www.polymer-project.org/0.5/docs/polymer/polymer.html#extending-other-elements to go by for extending elements.
<link rel="import" href="../bower_components/paper-dialog/paper-dialog.html">
<link rel="import" href="../bower_components/paper-icon-button/paper-icon-button.html">
<link rel="import" href="../bower_components/iron-icons/iron-icons.html">
<link rel="import" href="../bower_components/google-youtube/google-youtube.html">
<link rel="import" href="../bower_components/polymer/polymer.html">
<dom-module id="video-player">
<template>
<div class="layout horizontal">
<paper-button dialog-dismiss>
<paper-icon-button icon="arrow-back"></paper-icon-button>
</paper-button>
</div>
<div style="height: 100%; width: 100%">
<google-youtube style="height: 100%;"
video-id="YMWd7QnXY8E"
rel="1"
start="5"
playsinline="0"
controls="2"
showinfo="0"
width="100%"
height="100%"
autoplay="1">
</google-youtube>
</div>
</template>
<script>
Polymer({
is: "video-player"
});
</script>
<paper-dialog name="video-player" extends="video-player">
<template>
<shadow></shadow>
</template>
<script>
Polymer();
</script>
</paper-dialog>
<video-player></video-player>
As was mentioned in the comments, you can't yet extend custom elements, so the existing pattern (or at least the one I use) is to make use of behaviors wherever possible and wrappers wherever not.
e.g.
<dom-module id="popup-video-player">
<template>
<video-player></video-player>
</template>
<script>
Polymer({
is: 'popup-video-player',
behaviors: [Polymer.PaperDialogBehavior],
...
});
</script>
</dom-module>
Now you can use <popup-video-player> just like a paper-dialog.
I know it stinks because if video-player has a bunch of properties that you want access to, you have to copy them in the popup-video-player element's API, which is not exactly DRY.
If you look at the paper-input source, you'll see them doing the same thing. It's obvious that they want to extend iron-input, but they can't so you get things like this:
<input is="iron-input" id="input"
aria-labelledby$="[[_ariaLabelledBy]]"
aria-describedby$="[[_ariaDescribedBy]]"
disabled$="[[disabled]]"
title$="[[title]]"
... >
As a side note, you could always hook into the <video-player>s "properties" property and make the API additions programatically.
maybe something like this would work: (untested!)
Polymer({
...
properties: (function () {
var prop = {
//special properties specific to the pop up version of video-player
//..obviously be careful to avoid name space conflicts.
};
var video_player = document.createElement('video-player');
video_player.properties.keys().forEach( function(key) {
props[key] = video_player[key];
});
return props;
}()),
});

Polymer 1.0: polymer-element not showing

The below code does not show in the browser. This works in Polymer 0.5. Is there code difference as I am using 1.0?:
<link rel="import" href="../bower_components/polymer/polymer.html">
<polymer-element name="my-name">
<template>
<h1> Hello {{name}}</h1>
</template>
<script>
Polymer('my-name', {
ready: function() {
this.name = "Brown";
}
});
</script>
</polymer-element>
Basically you need to rewrite your element based on the new requirements. You can easily follow it in the migration guide, registration element section.
You should rewrite it like following:
<dom-module id="my-name">
<template>
<!--Keep in mind in polymer 1.0 you can't have whitespaces in bound tags-->
<h1>Hello <span>{{name}}</span></h1>
</template>
<script>
Polymer({
is: "my-name",
ready: function () {
this.name = "Brown";
}
});
</script>
</dom-module>
I did a Plunker where you can reproduce it.
<link rel="import" href="../bower_components/polymer/polymer.html">
<dom-module id="my-name">
<style>
/*your styles go here*/
<style>
<template>
<!-- Things to show in element view -->
<h1> Hello <span>{{name}}</span></h1>
</template>
<dom-module>
<script>
// Your script goes here
Polymer({
is: 'my-name',
properties: {
name: {
type: String,
value: 'Brown'
}
}
});
</script>
There are many differences when migrating from Polymer 0.5 to Polymer 1.0 +. They changed the old polymer-element to dom-module and name attribute to id. The constructor is also changed as i shown in the example. Read https://www.polymer-project.org/1.0/docs/migration.html to get more info on migrating.
polymer 1.0 changes <polymer-element name="my-name"> to <dom-module id="my-name">.
I think you should follow the documentation of polymer 1.0
Polymer 1.0 documentation

Alternative to "in" expression for iterating over objects polymer (0.5.4)

Using the repeat and in expression it is trivial to iterate over arrays, but swapping
this.data = ["foo","bar"];
to
this.data = {foo:"football",bar:"barfly"}
fails to iterate over the object. I have seen examples of using Object.key in order to get each value, but the index returned is 0,1 instead of "foo" "bar".
While this simple example doesn't use 2 way binding, I would like to keep support for it, in case I need it in the future.
http://jsbin.com/copogeyome/1/
<!DOCTYPE html>
<html>
<head>
<meta charset=utf-8 />
<title>Polymer</title>
<script src="http://www.polymer-project.org/components/webcomponentsjs/webcomponents.js"></script>
<link rel="import" href="http://www.polymer-project.org/components/polymer/polymer.html">
</head>
<body>
<polymer-element name="an-consumer" attributes="data" noscript>
<template>testing {{data.foo}}<br>
<template id="foo">f {{}}<br></template>
<template id="bar">b {{}}<br></template>
<template id="0">0 {{}}<br></template>
<template id="1">1 {{}}<br></template>
<template id="2">2 {{}}<br></template>
{
<template repeat="{{obj,index in data}}" bind="{{data}}">
( {{index}} - {{obj}} ) = <template ref="{{index}}" bind="{{obj}}"></template>
</template>
}
</template>
</polymer-element>
<polymer-element name="an-supplier" attributes="data">
<template></template>
<script>
Polymer({
ready: function(){
this.data = ["foo","bar"];
//this.data = {foo:"football",bar:"barfly"}
}
});
</script>
</polymer-element>
<polymer-element name = "an-root" noscript>
<template>
<an-supplier data="{{stuff}}"></an-supplier>
<an-consumer data="{{stuff}}"></an-consumer>
</template>
</polymer-element>
<an-root>
</an-root>
</body>
</html>
While there is [yet] no built-in ability to iterate over object, you might easily achieve this functionality with filter:
<template repeat="{{key in data | getKeys}}">
<span>Key: {{key}}</span>
<span>Value: {{data[key]}}</span>
</template>
<script>
Polymer({
ready: function(){
// this.data = ["foo","bar"];
this.data = {foo:"football",bar:"barfly"}
}
// filter function to use in looping objects
getKeys : function(o) {
return Object.keys(o);
}
});
</script>
Whether you have additional questions, please, don’t hesitate to ask.
Live: http://jsbin.com/munehitogu/1/edit

Polymer: how to parse the index to the elements using template repeat

I've been trying to use Polymer for a project I'm working on. And although I enjoyed it quite a lot so far, I ran into a problem I just can't solve.
I dumped it down to a simple example. Basically it's just a list element (item-list) that contains item elements (item-card) and i want to parse the items position to the element via the attribute pos. But for some reason the items attribute is allways undefined! Is this because the attribute is bound to the variable i, which dies after the template repeat? If so, how do I work around it? Is there a different approach I should be using here?
SOLUTION: You can find the solution by reading through all the comments, but to sum it up: apperantly there was a timing issue and the attribute wasn't ready at the ready callback. But I found out about the domReady callback (polymer lifecycle documentation). Using domReady it works just fine! Thanks to Günter Zöchbauer for the help!
This is the item-list.html:
<link rel="import" href="components/polymer/polymer.html">
<link rel="import" href="item-card.html">
<polymer-element name="item-list">
<template>
<style>
</style>
<template repeat="{{values, i in data.data}}">
<item-card pos="{{i}}"></item-card>
</template>
</template>
<script>
Polymer({
created: function()
{
this.num = 123456;
this.data = { "data":
[
{
"value":999
},
{
"value":666
},
{
"value":555
},
{
"value":222
}
]
};
}
});
</script>
</polymer-element>
This is the item-card.html
<link rel="import" href="components/polymer/polymer.html">
<polymer-element name="item-card" attributes="pos">
<template>
<style>
</style>
</template>
<script>
Polymer({
ready: function()
{
console.log("ready: " + this.pos);
}
});
</script>
</polymer-element>
I didn't bother putting the index.html in, since it just containts one item-list element.
Thanks alot!!
I think you need a pos field in <item-card> in addition to the attributes="pos" declaration.
The repeated element also references the bound model which can be accessed like querySelector('item-card').templateInstance.model property.
See https://github.com/PolymerLabs/polymer-selector/blob/master/polymer-selector.html#L286 for an example.
Info:
According to the comments it turned out to be a timing issue. The value wasn't yet assigned when the ready callback was called but using domReady worked.