Implement TControl::__isset() to check for sub controls

Fix #594

2 files changed, 26 insertions, 1 deletions

diff --git a/HISTORY b/HISTORY
index 90194aed..8482c526 100644
--- a/HISTORY
+++ b/HISTORY
@@ -3,9 +3,9 @@ Version 3.3.2 xxx, 2016
 BUG: Issue #592 - Fix TActiveMultiView brokwn on 3.3.1 (ctrlaltca)
 BUG: Issue #588 - Fix reading values of controls inside TJuiDialog (ctrlaltca)
 ENH: Issue #591 - Support for hyphenated attributes via <prop:*></prop:*> template syntax (emkael)
+ENH: Issue #594 - Added ability to check for subcontrols using isset(), empty() (jojoinside)
 ENH: Allow TStyle behaviors (LCSKJ)
 
-
 Version 3.3.1 April 19, 2016
 
 BUG: Issue #540 - Fix TActiveFileUpload on IE11 (ctrlaltca)
diff --git a/framework/Web/UI/TControl.php b/framework/Web/UI/TControl.php
index be7b1185..1b8a2138 100644
--- a/framework/Web/UI/TControl.php
+++ b/framework/Web/UI/TControl.php
@@ -196,6 +196,31 @@ class TControl extends TApplicationComponent implements IRenderable, IBindable
 	}
 
 	/**
+	 * Checks for the existance of a property value by name or a control by ID.
+	 * This overrides the parent implementation by allowing checking for the
+	 * existance of a control via its ID using the following syntax,
+	 * <code>
+	 * $menuBarExists = isset($this->menuBar);
+	 * </code>
+	 * Do not call this method. This is a PHP magic method that we override
+	 * to allow using isset() to detect if a component property is set or not.
+	 * Note, the control must be configured in the template
+	 * with explicit ID. If the name matches both a property and a control ID,
+	 * the control ID will take the precedence.
+	 *
+	 * @param string the property name or control ID
+	 * @return bool wether the control or property exists
+	 * @see __get
+	 */
+	public function __isset($name) {
+		if(isset($this->_rf[self::RF_NAMED_OBJECTS][$name])) {
+			return true;
+		} else {
+			return parent::__isset($name);
+		}
+	}
+
+	/**
 	 * @return boolean whether there is an adapter for this control
 	 */
 	public function getHasAdapter()