Add a section about form.submit action and input change events #7275
Description
We landed support for input change event and exposing form.submit action that can be used together to support submit-on-change kind of behavior.
We need to update AMP-form docs to add a section about form.submit action and input change event. See the forms.amp.html example for more details on syntax and usage.
<form method="post"
id="poll1"
action-xhr="/form/json/poll1"
target="_blank">
<fieldset>
<p>What is your favorite flightless bird?</p>
<label>
<input name="question1" value="Penguins" type="radio" on="change:poll1.submit">
Penguins
</label>
<label>
<input name="question1" value="Ostriches" type="radio" on="change:poll1.submit">
Ostriches
</label>
<label>
<input name="question1" value="Kiwis" type="radio" on="change:poll1.submit">
Kiwis
</label>
<label>
<input name="question1" value="Wekas" type="radio" on="change:poll1.submit">
Wekas
</label>
</fieldset>
</form>Reference bug: #4272