Added icon for fieldtype

src/fields/QRCodeField.php

@@ -50,6 +50,14 @@ public static function displayName(): string
         return Craft::t('qrcode', 'QR Code');
     }
 
+     /**
+     * @inheritdoc
+     */
+    public static function icon(): string
+    {
+        return __DIR__ . '/../assetbundles/qrcodefieldfield/dist/img/qrcode-fieldtype-icon.svg';
+    }
+
     // Public Methods
     // =========================================================================
 
@@ -59,11 +67,10 @@ public static function displayName(): string
     public function rules(): array
     {
         $rules = parent::rules();
-        $rules = array_merge($rules, [
+        return array_merge($rules, [
             ['property', 'string'],
             ['property', 'required'],
         ]);
-        return $rules;
     }
 
     /**

src/templates/_components/fields/QRCodeField_settings.twig

@@ -19,10 +19,12 @@
 
 {{ forms.textareaField({
 	label: "Data Format"|t,
-	instructions: ""|t,
+	instructions: "Define the format of the a QR code to be shown in the control panel. Use Twig to dynamically retrieve properties of the element that the fieldtype is set on. It may be a simple string, i.e. `{{ entry.title }}`, or a full JSON string, i.e., `{ \"title\" : \"{{ entry.title }}\" }`."|t,
 	id: 'property',
 	name: 'property',
+	class: 'code',
+	required: true,
 	value: field.property ? field.property|raw,
 	errors: field.getErrors('property'),
-    rows: 8
+    rows: 6
 }) }}