How Set focus to CharField of a django form element

Question

Am using Django's form for my login page. I want to set focus to the first textField (username) when the page loads. I tried using Jquery as follows, But doen't get the result.

forms.py:
from django import forms
class LoginForm(forms.Form):
    userName = forms.EmailField(max_length=25)     
    password = forms.CharField( widget=forms.PasswordInput, label="password" )

Login.html

% block headextra %}
    <script type="text/javascript">
        $(document).ready(function() {
             window.onload = function() {
             $("#id_username").focus();
             // alert('test') if I add this line its works
             //  setting focus to a textbox which added to template page direcltly using html tag the focus() method works well
            };  
        }); 
        </script>       
    {% endblock %}

{% block content %} 
<form method = "POST" action ="/login/">{% csrf_token %}
<table align ="center">
    {{ form.as_table }}
<tr><td></td></tr>
<tr><td><input type="submit" value="Submit"></td></tr>
</table>
</from>

Answer 1

In html, all you need is autofocus without arguments.

In the Django form, add autofocus as key with empty value:

search = forms.CharField(
                label='Search for:',
                max_length=50,
                required=False,
                widget=forms.TextInput(attrs={'autofocus': ''}))

Answer 2

The proper Django way of answering this question is as follows (as it doesn't depend on js being enabled):

from django import forms

class LoginForm(forms.Form):
    user_name = forms.EmailField(max_length=25)     
    password = forms.CharField( widget=forms.PasswordInput, label="password" )

    def __init__(self):
        self.fields['user_name'].widget.attrs.update({'autofocus': 'autofocus'
            'required': 'required', 'placeholder': 'User Name'})
        self.fields['password'].widget.attrs.update({
            'required': 'required', 'placeholder': 'Password'})

Also, for the record, we avoid the use of camelcase for object attributes. Cheers!