I am working on a webpage using flask and wtforms. When opening the webpage, my selectfield should not hold any value (i.e. be blank, have placeholder saying "please choose an option" or something in that direction).
My form is defined like this in forms.py:
class Form(FlaskForm):
selectfield = SelectField('Title', choices=[])
I leave choices as an empty list because they are created from a database through the function get_choices:
# create instance of form
form = Form()
# run function to get data from db
form.selectfield.choices = get_choices()
Here it starts to get gnarly: Since the placeholder value should be empty (i.e. "") or something like "please choose" I don't want to have it in my database. So I add the value manually:
# append
form.selectfield.choices.append('Please choose')
The html part, where I render the form looks like this:
<form method="POST" action= {{ url_for('index') }}>
{{ form.csrf_token }}
{{ form.selectfield(class_="form-control", **{"onchange":"this.form.submit()"}) }}
</form>
What have I tried:
adding 'placeholder = "please choose"' here:
{{ form.selectfield(placeholder="please choose", class_="form-control", **{"onchange":"this.form.submit()"}) }}
(as suggested by Crast here: WTForms Can I add a placeholder attribute when I init a field?)
adding default="Please choose" to my Form class as suggested by Liu Yue (How do you set a default value for a WTForms SelectField?):
class Form(FlaskForm):
selectfield = SelectField('Title', choices=[], default="Please choose")
This works partly, but the Please Choose value should not be selectable which it still is.
I feel like I might be completely on a wrong path here, and maybe oversee a very simple feature. I really can't believe that such a popular feature is not available using wtforms. I am thankful for any advice and guidance.
