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问题:
All I want is to be able to get the input from a polymer element <paper-input> and alert it onchange WITHOUT creating a custom polymer element.
issues: on-change doesn't do anything I doubt this.value will do anything
Pseudocode:
<!DOCTYPE html> <html> <head><!--insert proper head elements here--></head> <body> <paper-input floatingLabel label="test" on-change="alert(this.value)"></paper-input> </body> </html>
回答1:
I don't know if the OP wanted a change callback while typing...but for Polymer 1.0+ one can listen to the changes while typing simply use the on-input instead of on-change "event"
<paper-input label="Enter search term" on-input="search" value="{{searchTerm}}">
回答2:
The on-* declarative event handlers are syntactic sugar provided by Polymer, so on-change won't work outside of a Polymer element. You can do the same thing in vanilla Javascript using querySelector and addEventListener:
<paper-input floatingLabel label="test"></paper-input> <script> document.querySelector('paper-input').addEventListener('change', function(event) { console.log(event.target.value); }); </script>
回答3:
<paper-input> element will fire 'value' property change event (a non-bubbling DOM event when a 'value' property changes)
elements declaration:
<paper-input label="Enter search term" on-value-changed="_onSearchTermChanged" value="{{searchTerm}}">
event handling:
_onSearchTermChanged: function (event) { console.log(event.detail.value); }
For more details check Polymer's Change Notification Events
回答4:
You can specify a custom change event name in the annotation using the following syntax https://www.polymer-project.org/1.0/docs/devguide/data-binding.html#two-way-native :
target-prop="{{hostProp::target-change-event}}"
回答5:
I was working with paper-slider and found out that the "on-change" doesn't do anything, but "onchange" triggered what I wanted. Since paper-input is a Polymer element, it should work with the declarative event handling.