Avoid some PHP warnings

- Undefined array keys
- Undefined class variables
- Passing null to string functions

api/src/Etemplate/Widget/Date.php

@@ -114,7 +114,7 @@ class Date extends Transformer
 			return $value;
 		}    // otherwise we will get current date or 1970-01-01 instead of an empty value
 
-		$format = $this->attrs['dataFormat'] ?? $this->attrs['data_format'];
+		$format = $this->attrs['dataFormat'] ?? $this->attrs['data_format'] ?? "";
 		// for DateTime objects (regular PHP and Api\DateTime ones), set user timezone
 		if($value instanceof \DateTime)
 		{

api/src/Etemplate/Widget/Grid.php

@@ -189,7 +189,7 @@ class Grid extends Box
 			foreach(array_merge(array($direct_child), $n ? array() : $direct_child->children) as $child)
 			{
 				$pat = $child->id;
-				while(($patstr = strstr($pat, '$')))
+				while($pat && ($patstr = strstr($pat, '$')))
 				{
 					$pat = substr($patstr, $patstr[1] == '{' ? 2 : 1);
 

api/src/Etemplate/Widget/Nextmatch.php

@@ -136,7 +136,7 @@ class Nextmatch extends Etemplate\Widget
 		}
 
 		// Check for sort preference.  We only apply this on first load so it can be changed
-		if($GLOBALS['egw_info']['user']['preferences'][$app][$this->attrs['template'] . "_sort"])
+		if(array_key_exists($this->attrs['template'] . "_sort", $GLOBALS['egw_info']['user']['preferences'][$app]))
 		{
 			$send_value['sort'] = $GLOBALS['egw_info']['user']['preferences'][$app][$this->attrs['template'] . "_sort"];
 		}

api/src/Etemplate/Widget/Select.php

@@ -644,7 +644,7 @@ class Select extends Etemplate\Widget
 		}
 		// Legacy / static support
 		// Have to do this explicitly, since legacy options is not defined on class level
-		$legacy_options = explode(',',$_legacy_options);
+		$legacy_options = explode(',', $_legacy_options ?? "");
 		foreach($legacy_options as &$field)
 		{
 			$field = self::expand_name($field, 0, 0,'','',self::$cont);

api/src/Hooks.php

@@ -261,6 +261,10 @@ class Hooks
 				// some apps have setup_info for more then themselfs (eg. api for groupdav)
 				foreach($setup_info as $appname => $data)
 				{
+					if(!array_key_exists('hooks', $data))
+					{
+						continue;
+					}
 					foreach((array)$data['hooks'] as $location => $methods)
 					{
 						if (is_int($location))

importexport/inc/class.importexport_definitions_ui.inc.php

@@ -51,6 +51,10 @@ class importexport_definitions_ui
 	 * @var object
 	 */
 	var $plugin;
+	private Etemplate $etpl;
+	private string $clock;
+	private array $steps;
+	private $wizard_content_template;
 
 	function __construct()
 	{