Make table view and tree view resizeable

MainWindow.ui

@@ -26,10 +26,13 @@
    <string>MainWindow</string>
   </property>
   <widget class="QWidget" name="widget">
-   <layout class="QVBoxLayout" name="verticalLayout_2">
+   <layout class="QVBoxLayout" name="verticalLayout">
     <item>
-     <layout class="QVBoxLayout" name="verticalLayout">
+     <widget class="QSplitter" name="splitter">
-      <item>
+      <property name="orientation">
+       <enum>Qt::Vertical</enum>
+      </property>
+      <widget class="QWidget" name="">
        <layout class="QHBoxLayout" name="horizontalLayout">
         <item>
          <widget class="QLineEdit" name="lineEdit"/>
@@ -49,14 +52,10 @@
          </widget>
         </item>
        </layout>
-      </item>
+      </widget>
-      <item>
+      <widget class="QTableView" name="tableView"/>
-       <widget class="QTableView" name="tableView"/>
+      <widget class="QTreeView" name="treeView"/>
-      </item>
+     </widget>
-      <item>
-       <widget class="QTreeView" name="treeView"/>
-      </item>
-     </layout>
     </item>
    </layout>
   </widget>
@@ -79,7 +78,7 @@
     <property name="title">
      <string>File</string>
     </property>
-    <addaction name="action_2"/>
+    <addaction name="actionOpen"/>
     <addaction name="actionSave"/>
     <addaction name="actionSave_As"/>
     <addaction name="actionClose"/>
@@ -120,7 +119,7 @@
     <bool>false</bool>
    </attribute>
   </widget>
-  <action name="action_2">
+  <action name="actionOpen">
    <property name="text">
     <string>Open</string>
    </property>