Fixed displaying add button in case there is no definition of columns + update README

Author: Eugene Tupikov

CHANGELOG.md

@@ -4,6 +4,8 @@ Yii2 multiple input change log
 1.2.3 in development
 --------------------
 
+- Enh #34: Added options `allowEmptyList` (unclead)
+
 1.2.2
 -----
 

README.md

@@ -15,7 +15,7 @@ Contents:
 - [Installation](#installation)
 - [Configuration](#configuration)
 - [Usage](#usage)
-- [How to customize buttons](#customize-buttons)
+- [Tips and tricks](#tips)
 - [Javascript Events](#javascript-events)
 - [Renderers](#renderers)
 
@@ -241,7 +241,11 @@ You can find more detail about this use case [here](docs/tabular_input.md)
 
 > Also you can find source code of examples [here](./docs/examples/)
 
-## How to customize buttons
+
+
+## Tips and tricks
+
+### How to customize buttons
 
 You can customize `add` and `remove` buttons via `addButtonOptions` and `removeButtonOptions`. Here is the simple example
 how you can use those options:
@@ -262,6 +266,20 @@ how you can use those options:
 
 ```
 
+### Work with empty list
+
+In some cases you need to have the ability to delete all rows in the list. For this purpose you can use option `allowEmptyList` like in the example below:
+
+```php
+
+    echo $form->field($model, 'emails')->widget(MultipleInput::className(), [
+        'limit' => 5,
+        'allowEmptyList' => true
+    ])
+    ->label(false);
+
+```
+
 ## JavaScript events
 This widget has following events:
  - `afterInit`: triggered after initialization

examples/views/multiple-input.php

@@ -24,7 +24,8 @@
     <h3>Single column</h3>
 <?php
     echo $form->field($model, 'emails')->widget(MultipleInput::className(), [
-        'limit' => 5
+        'limit' => 5,
+        'allowEmptyList' => true
     ])
     ->label(false);
 ?>

src/renderers/TableRenderer.php

@@ -72,6 +72,9 @@ public function renderHeader()
      */
     private function hasHeader()
     {
+        if ($this->allowEmptyList) {
+            return true;
+        }
         foreach ($this->columns as $column) {
             /* @var $column BaseColumn */
             if (!empty($column->title)) {