Using null as an array offset is deprecated

Author: sukhwinder33445

library/Reporting/Web/Forms/ReportForm.php

@@ -155,15 +155,15 @@ protected function assemble(): void
             'required'    => true,
             'class'       => 'autosubmit',
             'label'       => $this->translate('Timeframe'),
-            'options'     => [null => $this->translate('Please choose')] + Database::listTimeframes(),
+            'options'     => ['' => $this->translate('Please choose')] + Database::listTimeframes(),
             'description' => $this->translate(
                 'Specifies the time frame in which this report is to be generated'
             )
         ]);
 
         $this->addElement('select', 'template', [
             'label'       => $this->translate('Template'),
-            'options'     => [null => $this->translate('Please choose')] + Database::listTemplates(),
+            'options'     => ['' => $this->translate('Please choose')] + Database::listTemplates(),
             'description' => $this->translate(
                 'Specifies the template to use when exporting this report to pdf. (Default Icinga template)'
             )
@@ -173,7 +173,7 @@ protected function assemble(): void
             'required'    => true,
             'class'       => 'autosubmit',
             'label'       => $this->translate('Report'),
-            'options'     => [null => $this->translate('Please choose')] + $this->listReports(),
+            'options'     => ['' => $this->translate('Please choose')] + $this->listReports(),
             'description' => $this->translate('Specifies the type of the reportlet to be generated')
         ]);
 

library/Reporting/Web/Forms/ScheduleForm.php

@@ -89,7 +89,7 @@ protected function assemble()
         $this->addElement('select', 'action', [
             'required'    => true,
             'class'       => 'autosubmit',
-            'options'     => array_merge([null => $this->translate('Please choose')], $this->listActions()),
+            'options'     => array_merge(['' => $this->translate('Please choose')], $this->listActions()),
             'label'       => $this->translate('Action'),
             'description' => $this->translate('Specifies an action to be triggered by the scheduler')
         ]);

library/Reporting/Web/Forms/TemplateForm.php

@@ -254,7 +254,7 @@ protected function addColumnSettings($name, $label)
             'class'   => 'autosubmit',
             'label'   => $label,
             'options' => [
-                null       => 'None',
+                ''         => 'None',
                 'text'     => 'Text',
                 'image'    => 'Image',
                 'variable' => 'Variable'