FIX Subsites VirtualPage link to edit main page and TreeDropdownField API implementations

javascript/SubsitesTreeDropdownField.js

@@ -4,14 +4,14 @@
 		 * Choose a subsite from which to select pages.
 		 * Needs to clear tree dropdowns in case selection is changed.
 		 */
-		$('.subsitestreedropdownfield-chooser').entwine({
+        $('select.subsitestreedropdownfield-chooser').entwine({
 			onchange: function() {
 				// TODO Data binding between two fields
-				// TODO create resetField method on API instead
-				var fields = $('.SubsitesTreeDropdownField');
-				fields.setValue(null);
-				fields.setTitle(null);
-				fields.find('.tree-holder').empty();
+                const name = this.attr('name').replace('_SubsiteID', '');
+                let field = $('#Form_EditForm_' + name).first();
+                field.setValue(0);
+                field.refresh();
+                field.trigger('change');
 			}
 		});
 
@@ -20,12 +20,15 @@
 		 * before asking for the tree.
 		 */
 		$('.TreeDropdownField.SubsitesTreeDropdownField').entwine({
-			getRequestParams: function() {
-				var name = this.find(':input[type=hidden]:first').attr('name') + '_SubsiteID',
-					source = $('[name=' + name + ']'), params = {};
-				params[name] = source.length ? source.val() : null;
-				return params;
-			}
+            getAttributes() {
+                const fieldName = this.attr('id').replace('Form_EditForm_', '');
+                const subsiteID = $('#Form_EditForm_' + fieldName + '_SubsiteID option:selected').val();
+
+                let attributes = this._super();
+                attributes.data.urlTree += "?" + fieldName + "_SubsiteID=" + subsiteID;
+                attributes.data.cacheKey = attributes.data.cacheKey.substring(0, 19) + "_" + subsiteID;
+                return attributes;
+            }
 		});
 	});
 })(jQuery);

src/Extensions/LeftAndMainSubsites.php

@@ -5,6 +5,7 @@
 use SilverStripe\Admin\AdminRootController;
 use SilverStripe\Admin\CMSMenu;
 use SilverStripe\Admin\LeftAndMainExtension;
+use SilverStripe\CMS\Controllers\CMSPagesController;
 use SilverStripe\CMS\Model\SiteTree;
 use SilverStripe\CMS\Controllers\CMSPageEditController;
 use SilverStripe\Control\Controller;
@@ -270,13 +271,31 @@ public function onBeforeInit()
                 $session->clear($sessionNamespace . '.currentPage');
             }
 
-            // Subsite ID has already been set to the state via InitStateMiddleware. If the user cannot view
-            // the current page, or we're in the context of editing a specific page, redirect to the admin landing
-            // section to prevent a loop of re-loading the original subsite for the current page.
-            if (!$this->owner->canView() || Controller::curr() instanceof CMSPageEditController) {
+            // Context: Subsite ID has already been set to the state via InitStateMiddleware
+
+            // If the user cannot view the current page, redirect to the admin landing section
+            if (!$this->owner->canView()) {
                 return $this->owner->redirect(AdminRootController::config()->get('url_base') . '/');
             }
 
+            $currentController = Controller::curr();
+            if ($currentController instanceof CMSPageEditController) {
+                /** @var SiteTree $page */
+                $page = $currentController->currentPage();
+
+                // If the page exists but doesn't belong to the requested subsite, redirect to admin/pages which
+                // will show a list of the requested subsite's pages
+                $currentSubsiteId = $request->getVar('SubsiteID');
+                if ($page && (int) $page->SubsiteID !== (int) $currentSubsiteId) {
+                    return $this->owner->redirect(CMSPagesController::singleton()->Link());
+                }
+
+                // Page does belong to the current subsite, so remove the query string parameter and refresh the page
+                // Remove the subsiteID parameter and redirect back to the current URL again
+                $request->offsetSet('SubsiteID', null);
+                return $this->owner->redirect($request->getURL(true));
+            }
+
             // Redirect to clear the current page, retaining the current URL parameters
             return $this->owner->redirect(
                 Controller::join_links($this->owner->Link(), ...array_values($this->owner->getURLParams()))
@@ -299,10 +318,7 @@ public function onBeforeInit()
             $canViewElsewhere = SubsiteState::singleton()->withState(function ($newState) use ($record) {
                 $newState->setSubsiteId($record->SubsiteID);
 
-                if ($this->owner->canView(Security::getCurrentUser())) {
-                    return true;
-                }
-                return false;
+                return (bool) $this->owner->canView(Security::getCurrentUser());
             });
 
             if ($canViewElsewhere) {

src/Extensions/SiteTreeSubsites.php

@@ -118,22 +118,24 @@ public function updateCMSFields(FieldList $fields)
                     'SubsiteOperations',
                     _t(__CLASS__ . '.SubsiteOperations', 'Subsite Operations'),
                     [
-                        new DropdownField('CopyToSubsiteID', _t(
+                        DropdownField::create('CopyToSubsiteID', _t(
                             __CLASS__ . '.CopyToSubsite',
                             'Copy page to subsite'
                         ), $subsitesMap),
-                        new CheckboxField(
+                        CheckboxField::create(
                             'CopyToSubsiteWithChildren',
                             _t(__CLASS__ . '.CopyToSubsiteWithChildren', 'Include children pages?')
                         ),
-                        $copyAction = new FormAction(
+                        $copyAction = FormAction::create(
                             'copytosubsite',
                             _t(__CLASS__ . '.CopyAction', 'Copy')
                         )
                     ]
                 )->setHeadingLevel(4)
             );
 
+            $copyAction->addExtraClass('btn btn-primary font-icon-save ml-3');
+
             // @todo check if this needs re-implementation
 //            $copyAction->includeDefaultJS(false);
         }

src/Forms/SubsitesTreeDropdownField.php

@@ -5,6 +5,7 @@
 use SilverStripe\Control\Controller;
 use SilverStripe\Control\HTTPRequest;
 use SilverStripe\Forms\TreeDropdownField;
+use SilverStripe\Subsites\Model\Subsite;
 use SilverStripe\View\Requirements;
 use SilverStripe\Subsites\State\SubsiteState;
 
@@ -20,7 +21,10 @@ class SubsitesTreeDropdownField extends TreeDropdownField
         'tree'
     ];
 
-    protected $subsiteID = 0;
+    /**
+     * @var int
+     */
+    protected $subsiteId = 0;
 
     /**
      * Extra HTML classes
@@ -39,20 +43,42 @@ public function Field($properties = [])
         return $html;
     }
 
-    public function setSubsiteID($id)
+    /**
+     * Sets the subsite ID to use when generating the tree
+     *
+     * @param int $id
+     * @return $this
+     */
+    public function setSubsiteId($id)
     {
-        $this->subsiteID = $id;
+        $this->subsiteId = $id;
+        return $this;
     }
 
-    public function getSubsiteID()
+    /**
+     * Get the subsite ID to use when generating the tree
+     *
+     * @return int
+     */
+    public function getSubsiteId()
     {
-        return $this->subsiteID;
+        return $this->subsiteId;
     }
 
+    /**
+     * Get the CMS tree with the provided subsite ID applied to the state
+     *
+     * {@inheritDoc}
+     */
     public function tree(HTTPRequest $request)
     {
-        $results = SubsiteState::singleton()->withState(function () use ($request) {
-            SubsiteState::singleton()->setSubsiteId($this->subsiteID);
+        // Detect subsite ID from the request
+        if ($request->getVar($this->getName() . '_SubsiteID')) {
+            $this->setSubsiteId($request->getVar($this->getName() . '_SubsiteID'));
+        }
+
+        $results = SubsiteState::singleton()->withState(function (SubsiteState $newState) use ($request) {
+            $newState->setSubsiteId($this->getSubsiteId());
             return parent::tree($request);
         });
 

src/Pages/SubsitesVirtualPage.php

@@ -2,14 +2,17 @@
 
 namespace SilverStripe\Subsites\Pages;
 
+use SilverStripe\CMS\Controllers\CMSPageEditController;
 use SilverStripe\CMS\Model\SiteTree;
 use SilverStripe\CMS\Model\VirtualPage;
 use SilverStripe\Control\Controller;
 use SilverStripe\Core\Config\Config;
 use SilverStripe\Forms\DropdownField;
 use SilverStripe\Forms\LabelField;
+use SilverStripe\Forms\LiteralField;
 use SilverStripe\Forms\TextareaField;
 use SilverStripe\Forms\TextField;
+use SilverStripe\Forms\TreeDropdownField;
 use SilverStripe\ORM\ArrayList;
 use SilverStripe\ORM\DataObject;
 use SilverStripe\Subsites\Forms\SubsitesTreeDropdownField;
@@ -59,34 +62,42 @@ public function getCMSFields()
         );
 
         // Setup the linking to the original page.
-        $pageSelectionField = new SubsitesTreeDropdownField(
+        $pageSelectionField = SubsitesTreeDropdownField::create(
             'CopyContentFromID',
-            _t('SilverStripe\\CMS\\Model\\VirtualPage.CHOOSE', 'Choose a page to link to'),
-            "SilverStripe\\CMS\\Model\\SiteTree",
+            _t('SilverStripe\\CMS\\Model\\VirtualPage.CHOOSE', 'Linked Page'),
+            SiteTree::class,
             'ID',
             'MenuTitle'
         );
 
+        $fields->addFieldToTab(
+            'Root.Main',
+            TreeDropdownField::create('CopyContentFromID', 'Linked Page', SiteTree::class)
+        );
+
         if (Controller::has_curr() && Controller::curr()->getRequest()) {
-            $subsiteID = Controller::curr()->getRequest()->requestVar('CopyContentFromID_SubsiteID');
+            $subsiteID = (int) Controller::curr()->getRequest()->requestVar('CopyContentFromID_SubsiteID');
             $pageSelectionField->setSubsiteID($subsiteID);
         }
         $fields->replaceField('CopyContentFromID', $pageSelectionField);
 
         // Create links back to the original object in the CMS
         if ($this->CopyContentFromID) {
-            $editLink = "admin/pages/edit/show/$this->CopyContentFromID/?SubsiteID=" . $this->CopyContentFrom()->SubsiteID;
+            $editLink = Controller::join_links(
+                CMSPageEditController::singleton()->Link('show'),
+                $this->CopyContentFromID
+            );
+
             $linkToContent = "
 				<a class=\"cmsEditlink\" href=\"$editLink\">" .
                 _t('SilverStripe\\CMS\\Model\\VirtualPage.EDITCONTENT', 'Click here to edit the content') .
                 '</a>';
             $fields->removeByName('VirtualPageContentLinkLabel');
             $fields->addFieldToTab(
                 'Root.Main',
-                $linkToContentLabelField = new LabelField('VirtualPageContentLinkLabel', $linkToContent),
+                $linkToContentLabelField = LiteralField::create('VirtualPageContentLinkLabel', $linkToContent),
                 'Title'
             );
-            $linkToContentLabelField->setAllowHTML(true);
         }