when using krajee plugin, (Try to get a property of non object)when click on upload button.

I am using the krajee, ajax file input plugin with laravelframwork.when i m click on upload button so it gives an error of "create default object from empty value". If anyone know about this error how to resolve it kindly reply me. My html code is;

Scripts code is;

   $("#input-700").fileinput({
        uploadUrl: "", // server upload action
        uploadAsync: true,
       initialPreview: s.photoInitialPreview,
       previewFileType: "image",
       initialPreviewAsData: true,
       data: {'_token': ""},
        maxFileCount: 4,
        uploadExtraData: {'_token': ""}
    });

And my controller code is; public function productImage(Request $request) {

    $productImage = new ProductImage;
    $file = Input::file('image_path');
    $productImage = $request->product_id;
    if ($file) {
        $userId = Auth::user()->id;
        $destinationPath = public_path('assets/uploads/' . $userId . '/images/');
        $filename = $userId . '-' . time() . "." . $file->getClientOriginalExtension();
        $file->move($destinationPath, $filename);
        $productImage->image_path = $filename;
        }
        $productImage->save();

// return redirect()->back(); }

via Chebli Mohamed