Twig / Symfony表单模板语法

Question

I'm trying to modify someone else's website setup (a Craft CMS with a Laravel plugin) but I can't decipher the syntax of this Twig form, I was hoping someone more familiar with Twig/Symfony form templating could tell me what's going on or point me to the right documentation.

Specifically, I have a variable I want to render as a placeholder in an input. So {{ myvariable }} should be <input type="text" placeholder="{{ myvariable }}" ..., but I'm unfamiliar with how the inputs are being rendered.

Here's what's in the Twig template:

{% include "dir/content_type/_field" with {
   control: { handle: 'location_address_1', value: 'address_1'},
    element: content_type,
    errors: errors is defined ? errors : null
 } only %}

The _field I assume is a nearby html template, which has:

{% set field = craft.fields.getFieldbyHandle(control['handle']) %}
{% set fieldtype = craft.fields.populateFieldType(field, element) %}
{% set value = element ? element[control['value']] : null %}
{% set required = required is defined ? required : false %}
{% set input = fieldtype.getInputHtml(field.handle, value) %}
{% set label = no_label is defined and no_label ? '' : field.name|t|e%}
{% set errors = errors is defined and errors[control['value']] is defined ?     errors[control['value']] : null %}
{% include "_includes/forms/field" with {
  label: label,
  id: field.handle,
  errors: errors,
  input: input,
  required: required
} only %}

Any insight is appreciated.

Answer 1

The _field template is setting some parameters for the field based on the initial include call. The _field processes some of those parameters and then calls the _includes/forms/field with the processed values and field html in the input variable.

craft.fields.getFieldbyHandle() gets your field object. The from that object It looks like fieldtype.getInputHtml(field.handle, value)` is generating the actual HTML for the input. So you need to find where getInputHtml is defined and pass through your placeholder to there. Change that function to build the html with you placeholder attribute.

Something like so

final template

{% include "dir/content_type/_field" with {
    control: { handle: 'location_address_1', value: 'address_1', placeholder: "[Place holder value]"},
    element: content_type,
    errors: errors is defined ? errors : null     
 } only %}

_field

...
{% set input = fieldtype.getInputHtml(field.handle, value, control['placeholder']) %}

getInputHTML(handle,value, placeholder)

<input type="text" placeholder="{{ placeholder }}" ...