OpenCart无法添加或编辑产品

My OpenCart version 1.5.6 and I'm not using vQmod. So recently I added one custom product field. This tutorial helped me to do that http://forum.opencart.com/viewtopic.php?f=22&t=36625#p181916 Now, when I'm trying to add a new product to store this error appears:

Fatal error: Call to undefined method ModelCatalogCategory::getAllCategories() in C:\apache\localhost\www\webshop.kg\admin\controller\catalog\product.php on line 1018

If I'm trying to edit already existing product these two errors appear:

Notice: Undefined index: seo_title in C:\apache\localhost\www\webshop.kg\admin\model\catalog\product.php on line 456Notice: Undefined index: seo_h1 in C:\apache\localhost\www\webshop.kg\admin\model\catalog\product.php on line 457
Fatal error: Call to undefined method ModelCatalogCategory::getAllCategories() in C:\apache\localhost\www\webshop.kg\admin\controller\catalog\product.php on line 1018

What possible reason could create such a behavior?

Thank you for your attention.

The problem is within your controller as the model in admin/model/catalog/category.php does not contain a method getAllCategories() (unless you added it there which is not a case because of the fatal error) - it contains only the method getCategories().

Furthermore your Undefined index notices are saying that within your product model (lines 456 and 457) you are relying on the presence of the indexes seo_title and seo_h1 but they are not set.

I do not know the code you have modified in admin/model/catalog/product.php but you should use something like this:

if(isset($data['seo_title'])) { /* do setting of seo title */ } /* else { do not set this } */
if(isset($data['seo_h1'])) { /* do setting of seo h1 */ } /* else { do not set this } */

Maybe posting the method reliable for storing new or updating existing product code would be more helpful...

The model in admin/model/catalog/category.php does not contain a method getAllCategories(). So you need to define it in category model.

public function getAllCateories() {
    $query = "WRITE YOUR QUERY";
}