framework/ember/app/templates/signup.hbs

<div class="modal-content">
  <button class="close btn btn-icon btn-link" {{action "closeModal"}}>{{fa-icon "times"}}</button>
  <form {{action "submit" on="submit"}}>
    <div class="modal-header">
      <h3>Sign Up</h3>
    </div>
    <div class="modal-body">
      <div class="form-centered">
        <div class="form-group">
          {{input value=username name="username" type="text" class="form-control" placeholder="Username" disabled=loading}}
        </div>
        <div class="form-group">
          {{input value=email name="email" type="text" class="form-control" placeholder="Email" disabled=loading}}
        </div>
        <div class="form-group">
          {{input value=password name="password" type="password" class="form-control" placeholder="Password" disabled=loading}}
        </div>
        <div class="form-group">
          <button type="submit" class="btn btn-primary btn-block" {{bind-attr disabled=loading}}>Sign Up</button>
        </div>
      </div>
    </div>
    <div class="modal-footer">
      <p class="log-in-link">Already have an account? <a href="#" {{action "login"}}>Log In</a></p>
    </div>
  </form>
</div>
{{ui/loading-indicator classNameBindings=":modal-loading loading:active"}}