Why i'm Getting Call to a member function formName() on null in yii2

Question

I can't find any supporting resources for the error Call to a member function formName() on null. The scenario of getting this error when opening a update page. I've checked the rendered variable on update page by print_r() and its fine. Then I checked by removing the all input field which codes in yii2 ActiveFrom chtml

<?= $form->field($model, 'name')->textInput(['maxlength' => true, 'class' => ' form-control']) ?> 

and kept some input fields which is in normal html syntax

<input type="text" class="qty" name="qty[]" value="1" style="width: 24px;" value="<?php echo $value->qty; ?>">

Then it worked. Why this error occurred and how to fix it. Thanks,

Answer 1

You are probably not passing an update model from controller's action to view. Make sure you pass the loaded model in your update action to view like this:

public function actionUpdate($id)
{
    $model = $this->findModel($id);
    //... other update action code

    return $this->render('update', ['model' => $model]);
}

If you are using some common _form template that you include into your create/update templates you also have to make sure the $model is passed from your update template to the _form template.

<!-- ... your update template code ... -->
<?= $this->render('_form', ['model' => $model]); ?>
<!-- ... the rest of update template ... -->

Another option is that you are overwiriting the $model variable somewhere in your templates.