Zend: Redirect from form without validation

Question

I have a form for the creation of new "groups". I now added a small "go back" image with which the user should be able to go back one step. I don't know why, but when I click this new image, the controller and action used for the form which I want to leave (/admin/creategroup) is called again with HTTP POST set. Therefore, the form validation is done, and I'm stuck at this form with the validation errors displayed.

This is a snippet of the code from my form with both image-buttons. I wan't the "go back"-image to redirect me to the specified controller without validating the form:

    $this->addElement('image', 'btnBack', array (
        'name' => 'btnBack',
        'id'   => 'btnBack',
        'label' => '',
        'title' => 'Go back',
        'alt' => 'Go back',
        'src' => '/img/undo.png',
        'onClick' => "window.location='/admin/groupoverview'"
    ));

    $this->addElement('image', 'btnSave', array (
        'name' => 'btnSave',
        'id'   => 'btnSave',
        'label' => '',
        'title' => 'Save this new group',
        'alt' => 'Save this new group',
        'src' => '/img/save.png',
        'onClick' => "document.forms[0].submit();"
    ));

Edit:
I already thought of the possibility to check in /admin/creategroup whether it was called from the 'btnBack'-image or the 'btnSave'-image and skip form validation and redirect correctly if the source was the 'btnBack'-image.
I just think that there should be a nicer solution to directly redirect from the form and circumvent calling /admin/creategroup again.

Edit2:
My view script:

<div id="createGroupMask">
    <br/>
    Use the form below to create a new group
    <?php
        $this->form->setAction($this->url());
        echo $this->form;
    ?>
</div>

My action in the controller:

public function creategroupAction()
{
    $form = new Application_Form_CreateGroup();
    $request = $this->getRequest();

    if ($request->isPost()) {
        if ($form->isValid($request->getPost())) {
            // Data for new group is valid
            ...
        } else {
            // Form data was invalid
            // => This is where I land when pressing the 'back' image
            // No further code here
        }
    }
    $this->view->form = $form;
}

Answer 1

Now there is something to work with:

The isValid() loop is incorrect, your form will never evaluate as inValid with respect to the elements you've presented, you will never get to the else.

public function creategroupAction()
{
    $form = new Application_Form_CreateGroup();
    $request = $this->getRequest();

    if ($request->isPost()) {
        if ($form->isValid($request->getPost())) {
            // Data for new group is valid
            ...
        } else {
/* This is incorrect */
            // Form data was invalid
            // => This is where I land when pressing the 'back' image
            // No further code here
        }
    }
    $this->view->form = $form;
}

My problem is that I'm not sure what is going to be submitted from your form, I'm not really familiar with how your using "onClick" and what I presume is javascript. It looks like element btnBack should redirect on click and element btnSave should POST. However this does not seem to be happening.

I have done this type of thing in PHP and ZF with submit buttons, perhaps the flow of what I did will help:

NOTE: for this type of flow to work you must give the button element a label. The label is used as the submit value.

//psuedoCode
public function creategroupAction()
{
    $form = new Application_Form_CreateGroup();
    $request = $this->getRequest();

    if ($request->isPost()) {
        if ($form->isValid($request->getPost())) {
            //I would probably opt to perform this task with a switch loop
            if ($form->getValue('btnBack') === some true value) {
               $this->_redirect('new url');
            }
            if ($form->getValue('btnSave') === some true value) {
               //Process and save data
            }

        } else {
            //Display form errors
    }
    $this->view->form = $form;
}

I think when all is said and done the crux of your problem is that you did not give your button elements a label.

Answer 2

I tried adding labels to my images, but this didn't work.

I also tried to use the isChecked() method on my btnBack-image like this:

if ($form->btnBack->isChecked()) {
    // 'Go back' image was clicked so this is no real error, just redirect
}

This didn't work either.

I finally was able to check which image was clicked via the following method as answered in Zend form: image as submit button:

public function creategroupAction()
{
     $form = new Application_Form_CreateGroup();
     $request = $this->getRequest();

     if ($request->isPost()) {
         if ($form->isValid($request->getPost())) {
             // Data for new group is valid
             ...
         } else {
             // Form data was invalid

             if (isset($this->_request->btnBack_x)) {
                 // 'Go back' image was pressed, so this is no error
                 // -> redirect to group overview page
                 $this->_redirect('/admin/groupoverview');
             }
         }
     }
     $this->view->form = $form;
 }

I guess this doesn't thoroughly answer the original question as the validation is still done and I'm only checking for this 'special case' where the 'Go back' image was clicked, but I'll mark it as answered anyways.

Answer 3

Tim Fountain suggested an even cleaner approach in my somewhat related question: Zend forms: How to surround an image-element with a hyperlink?