python - Flask wtforms own style -

i want make registration flask:

@app.route('/register/', methods=['get','post']) def register():     form = registrationform(request.form)     if request.method == 'post' , form.validate():         username = form.username.data         mail = form.mail.data         password = sha256_crypt.encrypt((str(form.password.data)))         c, conn = dbconnect.conn()         x = c.execute("select * users username = (%s)", (thwart(username)))         if int(x) > 0:             flash("this username taken. please choose another!")             return render_template("register.html", form=form, nav=8)         else:             c.execute("insert users (username, password, mail, credits, settings, rank, items) values (%s, %s, %s, %s, %s, %s, %s)",                 thwart(username), thwart(password), thwart(mail), thwart(100), thwart(""), thwart(1), thwart(""))             conn.commit()             flash("you registered!")             c.close()             conn.close()             gc.collect()             session['logged_in'] = true             session['username'] = username             return redirect(url_for('dashboard'))     return render_template("register.html", form=form, nav=8) 

i'm using wtforms see. problem is, registration page is:

{% extends "default.html" %}  {% block body %}  <h4>register</h4> <form action="" method="post">     {% "_formhelpers.html" import render_field %}     {{ render_field(form.username) }}     {{ render_field(form.mail) }}     {{ render_field(form.password) }}     <p><input class="btn btn-primary form-control" type="submit" value="register"></p> </form>  {% endblock %} 

so render_field defined following:

{% macro render_field(field) %} {{ field(**kwargs)|safe }} {% endmacro %} 

but textboxes default style, no placeholder , no style. i'm using bootstrap , want formated like:

<p><input type="text" class="form-control" placeholder="{{ field.label }}" name="{{ field.label }}" value=""></p> 

how style them?

here how can write it

{% macro render_field(name, class='class-name', value='', type='text') -%} <input type="{{ type }}" name="{{ name }}" class="{{ class }}" value="{{ value }}"/> {%- endmacro %} 

your case

{% macro render_field(name, class='form-control', type='text') %} {{ field(**kwargs | safe) }} {% endmacro %} 

you can apply own style while rendering field.