diff --git a/module/programplan/tao.php b/module/programplan/tao.php
index 649b6e5687..b4f2d30d34 100644
--- a/module/programplan/tao.php
+++ b/module/programplan/tao.php
@@ -284,7 +284,7 @@ class programplanTao extends programplanModel
             $dateLimit    = $this->getTaskDateLimit($task, $plan);
             $data         = $this->buildTaskDataForGantt($task, $dateLimit);
             $data->id     = $task->execution . '-' . $task->id;
-            $data->parent = $task->parent > 0 ? $task->execution . '-' . $task->parent : $task->execution;
+            $data->parent = $task->parent > 0 && isset($tasks[$task->parent]) ? $task->execution . '-' . $task->parent : $task->execution;
             if(!isset($executions[$task->execution])) $executions[$task->execution] = $this->dao->select('status')->from(TABLE_EXECUTION)->where('id')->eq($task->execution)->fetch('status');
 
             /* Determines if the object is delay. */
diff --git a/module/programplan/ui/browse.html.php b/module/programplan/ui/browse.html.php
index b6560dfcbf..f3513f15f2 100644
--- a/module/programplan/ui/browse.html.php
+++ b/module/programplan/ui/browse.html.php
@@ -13,6 +13,7 @@ declare(strict_types=1);
 namespace zin;
 
 jsVar('browseType', $type);
+jsVar('isSearch', $browseType == 'bysearch');
 
 if(empty($plans))
 {
diff --git a/module/programplan/ui/gantt.html.php b/module/programplan/ui/gantt.html.php
index bcba24ae75..8e3fcccf36 100644
--- a/module/programplan/ui/gantt.html.php
+++ b/module/programplan/ui/gantt.html.php
@@ -15,6 +15,7 @@ namespace zin;
 data('fileName', 'gantt-export-' . $projectID);
 include './ganttfields.html.php';
 
+
 if($app->rawModule == 'programplan')
 {
     if($project->stageBy == 'product')
@@ -33,7 +34,11 @@ if($app->rawModule == 'programplan')
     }
     else
     {
-        featureBar(span(setClass('text font-bold'), $lang->programplan->gantt));
+        featureBar
+        (
+            btn(setClass('ghost mr-2', ($browseType != 'bysearch' ? 'active' : '')), $lang->programplan->gantt, set::url($this->createLink('programplan', 'browse', "projectID=$projectID&productID=$productID&type=gantt"))),
+            $hasSearch ? li(searchToggle(set::module('projectTask'), set::open($browseType == 'bysearch'))) : null
+        );
     }
     toolbar
     (
diff --git a/module/programplan/ui/ganttfields.html.php b/module/programplan/ui/ganttfields.html.php
index 2c594d348e..4d727dd8e9 100644
--- a/module/programplan/ui/ganttfields.html.php
+++ b/module/programplan/ui/ganttfields.html.php
@@ -31,12 +31,12 @@ $ganttLang->today            = $lang->programplan->today;
 
 $typeHtml  = '<a data-toggle="dropdown" href="#browseTypeList"><span class="text">' . $lang->programplan->ganttBrowseType[$ganttType] . '</span><span class="caret"></span></a>';
 $typeHtml .= '<menu class="dropdown-menu menu" id="browseTypeList">';
-foreach($lang->programplan->ganttBrowseType as $browseType => $typeName)
+foreach($lang->programplan->ganttBrowseType as $ganttBrowseType => $typeName)
 {
-    $link = $this->createLink('programplan', 'browse', "projectID=$projectID&productID=$productID&type=$browseType");
-    if($app->rawModule == 'review' and $app->rawMethod == 'assess') $this->createLink('review', 'assess', "reivewID=$reviewID&from=&type=$browseType");
+    $link = $this->createLink('programplan', 'browse', "projectID=$projectID&productID=$productID&type=$ganttBrowseType");
+    if($app->rawModule == 'review' and $app->rawMethod == 'assess') $this->createLink('review', 'assess', "reivewID=$reviewID&from=&type=$ganttBrowseType");
 
-    $typeHtml .= '<li class="menu-item' . ($ganttType == $browseType ? " active" : '') . '">' . html::a($link, $typeName, '', "class='item-content'") . '</li>';
+    $typeHtml .= '<li class="menu-item' . ($ganttType == $ganttBrowseType ? " active" : '') . '">' . html::a($link, $typeName, '', "class='item-content'") . '</li>';
 }
 $typeHtml .= '</menu>';