Initial data commit

Task/Visualize-a-tree/BBC-BASIC/visualize-a-tree.basic

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+      INSTALL @lib$+"WINLIB5"
+      ON ERROR SYS "MessageBox", @hwnd%, REPORT$, 0, 0 : QUIT
+
+      REM!WC Windows constants:
+      TVI_SORT = -65533
+      TVIF_TEXT = 1
+      TVM_INSERTITEM = 4352
+      TVS_HASBUTTONS = 1
+      TVS_HASLINES = 2
+      TVS_LINESATROOT = 4
+
+      REM. TV_INSERTSTRUCT
+      DIM tvi{hParent%,       \
+      \       hInsertAfter%,  \
+      \       mask%,          \
+      \       hItem%,         \
+      \       state%,         \
+      \       stateMask%,     \
+      \       pszText%,       \
+      \       cchTextMax%,    \
+      \       iImage%,        \
+      \       iSelectedImage%,\
+      \       cChildren%,     \
+      \       lParam%         \
+      \      }
+
+      SYS "InitCommonControls"
+      hTree% = FN_createwindow("SysTreeView32", "", 0, 0, @vdu.tr%, @vdu.tb%, 0, \
+      \                        TVS_HASLINES OR TVS_HASBUTTONS OR TVS_LINESATROOT, 0)
+      hroot% = FNinsertnode(0, "Root")
+      hchild1% = FNinsertnode(hroot%, "Child 1")
+      hchild2% = FNinsertnode(hroot%, "Child 2")
+      hchild11% = FNinsertnode(hchild1%, "Grandchild 1")
+      hchild12% = FNinsertnode(hchild1%, "Grandchild 2")
+      hchild21% = FNinsertnode(hchild2%, "Grandchild 3")
+      hchild22% = FNinsertnode(hchild2%, "Grandchild 4")
+
+      REPEAT
+        WAIT 1
+      UNTIL FALSE
+      END
+
+      DEF FNinsertnode(hparent%, text$)
+      LOCAL hnode%
+      text$ += CHR$0
+
+      tvi.hParent% = hparent%
+      tvi.hInsertAfter% = TVI_SORT
+      tvi.mask% = TVIF_TEXT
+      tvi.pszText% = !^text$
+
+      SYS "SendMessage", hTree%, TVM_INSERTITEM, 0, tvi{} TO hnode%
+      IF hnode% = 0 ERROR 100, "TVM_INSERTITEM failed"
+      SYS "InvalidateRect", hTree%, 0, 0
+      = hnode%