Wrap ImGui::TreeNode, TreePush, TreePop (#24)

Main.hs

@@ -91,6 +91,15 @@ loop w checked color slider = do
 
   colorPicker3 "Test" color
 
+  treeNode "Tree Node 1" >>= whenTrue do
+    treeNode "Tree Node 2" >>= whenTrue do
+      treePop
+
+    treeNode "Tree Node 3" >>= whenTrue do
+      treePop
+
+    treePop
+
   beginMainMenuBar >>= whenTrue do
     beginMenu "Hello" >>= whenTrue do
       menuItem "Hello"

src/DearImGui.hs

@@ -83,6 +83,11 @@ module DearImGui
   , colorPicker3
   , colorButton
 
+    -- * Trees
+  , treeNode
+  , treePush
+  , treePop
+
     -- ** Selectables
   , selectable
 
@@ -583,6 +588,25 @@ colorButton desc ref = liftIO do
 
     return changed
 
+-- | Wraps @ImGui::TreeNode()@.
+treeNode :: MonadIO m => String -> m Bool
+treeNode label = liftIO do
+  withCString label \labelPtr ->
+    (0 /=) <$> [C.exp| bool { TreeNode($(char* labelPtr)) } |]
+
+
+-- | Wraps @ImGui::TreePush()@.
+treePush :: MonadIO m => String -> m ()
+treePush label = liftIO do
+  withCString label \labelPtr ->
+    [C.exp| void { TreePush($(char* labelPtr)) } |]
+
+
+-- | Wraps @ImGui::TreePop()@.
+treePop :: MonadIO m => m ()
+treePop = liftIO do
+  [C.exp| void { TreePop() } |]
+
 
 -- | Wraps @ImGui::Selectable()@.
 selectable :: MonadIO m => String -> m Bool