imgui.TreeNode('Test Tree')
--[[
// Widgets: Trees
IMGUI_API bool TreeNode(const char* label); // if returning 'true' the node is open and the tree id is pushed into the id stack. user is responsible for calling TreePop().
IMGUI_API bool TreeNode(const char* str_id, const char* fmt, ...) IM_FMTARGS(2); // read the FAQ about why and how to use ID. to align arbitrary text at the same level as a TreeNode() you can use Bullet().
IMGUI_API bool TreeNode(const void* ptr_id, const char* fmt, ...) IM_FMTARGS(2); // "
IMGUI_API bool TreeNodeV(const char* str_id, const char* fmt, va_list args) IM_FMTLIST(2);
IMGUI_API bool TreeNodeV(const void* ptr_id, const char* fmt, va_list args) IM_FMTLIST(2);
IMGUI_API bool TreeNodeEx(const char* label, ImGuiTreeNodeFlags flags = 0);
IMGUI_API bool TreeNodeEx(const char* str_id, ImGuiTreeNodeFlags flags, const char* fmt, ...) IM_FMTARGS(3);
IMGUI_API bool TreeNodeEx(const void* ptr_id, ImGuiTreeNodeFlags flags, const char* fmt, ...) IM_FMTARGS(3);
IMGUI_API bool TreeNodeExV(const char* str_id, ImGuiTreeNodeFlags flags, const char* fmt, va_list args) IM_FMTLIST(3);
IMGUI_API bool TreeNodeExV(const void* ptr_id, ImGuiTreeNodeFlags flags, const char* fmt, va_list args) IM_FMTLIST(3);
IMGUI_API void TreePush(const char* str_id = NULL); // ~ Indent()+PushId(). Already called by TreeNode() when returning true, but you can call Push/Pop yourself for layout purpose
IMGUI_API void TreePush(const void* ptr_id = NULL); // "
IMGUI_API void TreePop(); // ~ Unindent()+PopId()
IMGUI_API void TreeAdvanceToLabelPos(); // advance cursor x position by GetTreeNodeToLabelSpacing()
IMGUI_API float GetTreeNodeToLabelSpacing(); // horizontal distance preceding label when using TreeNode*() or Bullet() == (g.FontSize + style.FramePadding.x*2) for a regular unframed TreeNode
IMGUI_API void SetNextTreeNodeOpen(bool is_open, ImGuiCond cond = 0); // set next TreeNode/CollapsingHeader open state.
IMGUI_API bool CollapsingHeader(const char* label, ImGuiTreeNodeFlags flags = 0); // if returning 'true' the header is open. doesn't indent nor push on ID stack. user doesn't have to call TreePop().
IMGUI_API bool CollapsingHeader(const char* label, bool* p_open, ImGuiTreeNodeFlags flags = 0); // when 'p_open' isn't NULL, display an additional small close button on upper right of the header
]]