diff --git a/src/NppJsonViewer/JsonViewDlg.cpp b/src/NppJsonViewer/JsonViewDlg.cpp
index 0fe6f5f..d0a66b6 100644
--- a/src/NppJsonViewer/JsonViewDlg.cpp
+++ b/src/NppJsonViewer/JsonViewDlg.cpp
@@ -466,18 +466,18 @@ void JsonViewDlg::AppendNodeCount(HTREEITEM node, unsigned elementCount, bool bA
     m_pTreeView->UpdateNodeText(node, txt);
 }
 
-void JsonViewDlg::UpdateNodePath(HTREEITEM htiNode)
+void JsonViewDlg::UpdateNodePath(HTREEITEM htiNode) const
 {
     std::wstring nodePath = m_pTreeView->GetNodePath(htiNode);
     CUtility::SetEditCtrlText(::GetDlgItem(_hSelf, IDC_EDT_NODEPATH), nodePath);
 }
 
-void JsonViewDlg::GoToLine(size_t nLineToGo)
+void JsonViewDlg::GoToLine(size_t nLineToGo) const
 {
     m_pEditor->GoToLine(nLineToGo);
 }
 
-void JsonViewDlg::GoToPosition(size_t nLineToGo, size_t nPos, size_t nLen)
+void JsonViewDlg::GoToPosition(size_t nLineToGo, size_t nPos, size_t nLen) const
 {
     m_pEditor->GoToPosition(nLineToGo, nPos, nLen);
 }
@@ -673,7 +673,7 @@ void JsonViewDlg::AdjustDocPanelSize(int nWidth, int nHeight)
     const auto moveWindowIDs = {IDC_BTN_SEARCH};
 
     // elements which requires both resizing and move
-    const auto resizeAndmoveWindowIDs = {IDC_EDT_NODEPATH};
+    const auto resizeAndMoveWindowIDs = {IDC_EDT_NODEPATH};
 
     const UINT flags = SWP_NOZORDER | SWP_NOOWNERZORDER | SWP_NOACTIVATE | SWP_NOCOPYBITS | SWP_SHOWWINDOW;
 
@@ -700,7 +700,7 @@ void JsonViewDlg::AdjustDocPanelSize(int nWidth, int nHeight)
         ::SetWindowPos(hWnd, NULL, rc.left + addWidth, rc.top, 0, 0, SWP_NOSIZE | flags);
     }
 
-    for (int id : resizeAndmoveWindowIDs)
+    for (int id : resizeAndMoveWindowIDs)
     {
         HWND hWnd = GetDlgItem(_hSelf, id);
 
@@ -895,7 +895,7 @@ void JsonViewDlg::EnableControls(const std::vector<DWORD>& ids, bool enable)
         EnableWindow(GetDlgItem(getHSelf(), id), enable ? TRUE : FALSE);
 }
 
-void JsonViewDlg::HandleTreeEvents(LPARAM lParam)
+void JsonViewDlg::HandleTreeEvents(LPARAM lParam) const
 {
     LPNMHDR lpnmh = reinterpret_cast<LPNMHDR>(lParam);
     if (!lpnmh || lpnmh->idFrom != IDC_TREE)
@@ -1029,7 +1029,7 @@ INT_PTR JsonViewDlg::run_dlgProc(UINT message, WPARAM wParam, LPARAM lParam)
         // Save ourselves in GWLP_USERDATA.
         ::SetWindowLongPtr(getHSelf(), GWLP_USERDATA, reinterpret_cast<LONG_PTR>(this));
 
-        m_pTreeView->OnInit(getHSelf());
+        m_pTreeView->OnInit(getHSelf(), IDC_TREE);
 
         PrepareButtons();
 
diff --git a/src/NppJsonViewer/JsonViewDlg.h b/src/NppJsonViewer/JsonViewDlg.h
index bff36e6..3fb2a32 100644
--- a/src/NppJsonViewer/JsonViewDlg.h
+++ b/src/NppJsonViewer/JsonViewDlg.h
@@ -59,9 +59,9 @@ class JsonViewDlg
 
     void ValidateJson();
 
-    void UpdateNodePath(HTREEITEM htiNode);
-    void GoToLine(size_t nLineToGo);
-    void GoToPosition(size_t nLineToGo, size_t nPos, size_t nLen);
+    void UpdateNodePath(HTREEITEM htiNode) const;
+    void GoToLine(size_t nLineToGo) const;
+    void GoToPosition(size_t nLineToGo, size_t nPos, size_t nLen) const;
 
     void SearchInTree();
 
@@ -89,7 +89,7 @@ class JsonViewDlg
     void ShowControls(const std::vector<DWORD>& ids, bool show);
     void EnableControls(const std::vector<DWORD>& ids, bool enable);
 
-    void HandleTreeEvents(LPARAM lParam);
+    void HandleTreeEvents(LPARAM lParam) const;
 
     auto GetFormatSetting() const -> std::tuple<LE, LF, char, unsigned>;
 
diff --git a/src/NppJsonViewer/TreeViewCtrl.cpp b/src/NppJsonViewer/TreeViewCtrl.cpp
index 844c685..d2ff8fd 100644
--- a/src/NppJsonViewer/TreeViewCtrl.cpp
+++ b/src/NppJsonViewer/TreeViewCtrl.cpp
@@ -2,13 +2,13 @@
 
 #include "TreeViewCtrl.h"
 #include "Define.h"
-#include "resource.h"
 
 
-void TreeViewCtrl::OnInit(HWND hParent)
+void TreeViewCtrl::OnInit(HWND hParent, int ctrlID)
 {
+    m_nCtrlID = ctrlID;
     m_hParent = hParent;
-    m_hTree   = GetDlgItem(m_hParent, IDC_TREE);
+    m_hTree   = GetDlgItem(m_hParent, m_nCtrlID);
 }
 
 auto TreeViewCtrl::InitTree() -> HTREEITEM
@@ -43,7 +43,7 @@ auto TreeViewCtrl::InsertNode(const std::wstring& text, LPARAM lparam, HTREEITEM
     tvInsert.item.pszText = const_cast<LPTSTR>(text.c_str());
     tvInsert.item.lParam  = lparam;
 
-    HTREEITEM item = reinterpret_cast<HTREEITEM>(SendDlgItemMessage(m_hParent, IDC_TREE, TVM_INSERTITEM, 0, reinterpret_cast<LPARAM>(&tvInsert)));
+    HTREEITEM item = reinterpret_cast<HTREEITEM>(SendDlgItemMessage(m_hParent, m_nCtrlID, TVM_INSERTITEM, 0, reinterpret_cast<LPARAM>(&tvInsert)));
 
     return item;
 }
diff --git a/src/NppJsonViewer/TreeViewCtrl.h b/src/NppJsonViewer/TreeViewCtrl.h
index 73dfb01..c5153af 100644
--- a/src/NppJsonViewer/TreeViewCtrl.h
+++ b/src/NppJsonViewer/TreeViewCtrl.h
@@ -11,13 +11,14 @@ class TreeViewCtrl
 {
     HWND   m_hTree              = nullptr;
     HWND   m_hParent            = nullptr;
+    int    m_nCtrlID            = 0;
     size_t m_nMaxNodeTextLength = 0;
 
 public:
     TreeViewCtrl()  = default;
     ~TreeViewCtrl() = default;
 
-    void OnInit(HWND hParent);
+    void OnInit(HWND hParent, int ctrlID);
 
     HWND GetTreeViewHandle() const
     {