A Cinema 4D Python TreeView example that supports Shift Clicking and Up/Down Arrows.

ObjectBrowser.pyp

"""ObjectBrowser
Based on: https://developers.maxon.net/?p=439"""

# ====== IMPORTS ====== #

import c4d


# ====== GLOBALS ====== #

debug = True

PLUGIN_ID = 1037588
PLUGIN_NAME = "Object Browser"
PLUGIN_HELP = "A simple treeview example"


# ====== UTILS ====== #

def GetNextElement(op):
    """Returns the next material or shader after `op`."""

    if not op:
        return

    if op.GetDown():
        return op.GetDown()

    while (not op.GetNext()) and op.GetUp():
        print "Up... ", op.GetUp().GetName()
        op = op.GetUp()

    return op.GetNext()


class ListItem():
    def __init__(self, obj):
        self.obj = obj

    def GetName(self):
        return self.obj.GetName()

    def IsSelected(self):
        return self.obj.GetBit(c4d.BIT_ACTIVE)

    def Select(self):
        self.obj.SetBit(c4d.BIT_ACTIVE)

    def Deselect(self):
        self.obj.DelBit(c4d.BIT_ACTIVE)

    def IsOpened(self):
        return self.obj.GetBit(c4d.BIT_OFOLD)

# ====== TREEVIEW ====== #

class ObjectTree(c4d.gui.TreeViewFunctions):
    """Data structure for a TreeView of Materials & Shaders."""

    def __init__(self, dlg):
        if debug:
            print "ObjectTree()"

        self.items = []
        self.LoadObjects()

    def LoadObjects(self):
        if debug:
            print "LoadObjects()"

        doc = c4d.documents.GetActiveDocument()
        if not doc:
            return

        obj = doc.GetFirstObject()
        while(obj is not None):
            wrapped_obj = ListItem(obj)
            self.items.append(wrapped_obj)
            obj = GetNextElement(obj)

    def GetFirst(self, root, userdata):
        """Returns the first Material in the document."""

        if self.items:
            return self.items[0]

    def GetDown(self, root, userdata, obj):
        """Get the next shader in the list."""

        return None

    def GetNext(self, root, userdata, obj):
        """Get the next material/shader in the list."""

        if obj in self.items:
            obj_index = self.items.index(obj)
            next_index = obj_index + 1
            if next_index < len(self.items):
                return self.items[next_index]

    def GetPred(self, root, userdata, obj):
        if obj in self.items:
            obj_index = self.items.index(obj)
            prev_index = obj_index - 1
            if prev_index > 0:
                return self.items[prev_index]

    def GetName(self, root, userdata, obj):
        """Returns the name of obj."""

        if not obj:
            return

        if not obj:
            return

        return obj.GetName()

    def IsOpened(self, root, userdata, obj):
        """Returns True if obj is unfolded."""

        return obj.IsOpened()

    def IsSelected(self, root, userdata, obj):
        """Returns True if obj is selected."""

        return obj.IsSelected()

    def Select(self, root, userdata, obj, mode):
        """Selects `obj` based on `mode`."""

        if debug:
            print "Select()"

        if mode == c4d.SELECTION_NEW:
            for item in self.items:
                item.Deselect()
                if item == obj:
                    item.Select()
        elif mode == c4d.SELECTION_ADD:
            obj.Select()
        elif mode == c4d.SELECTION_SUB:
            obj.Deselect()

    def Open(self, root, userdata, obj, onoff):
        """Folds or unfolds obj based on onoff."""

        print "Open()"

        if not obj:
            return

        if onoff:
            obj.SetBit(c4d.BIT_OFOLD)
        else:
            obj.DelBit(c4d.BIT_OFOLD)

        c4d.EventAdd()

# ====== DIALOG ====== #

class ObjectBrowser(c4d.gui.GeDialog):
    """Dialog that contains a list of Materials & Shaders in the active document."""

    _tree_gui = None

    def CreateLayout(self):
        """Build the overall dialog layout."""

        self.SetTitle(PLUGIN_NAME)

        # Build the ShaderTree GUI Element
        tree_gui_settings = c4d.BaseContainer()
        tree_gui_settings.SetLong(c4d.TREEVIEW_BORDER, c4d.BORDER_THIN_IN)
        tree_gui_settings.SetBool(c4d.TREEVIEW_HAS_HEADER, True)
        tree_gui_settings.SetBool(c4d.TREEVIEW_HIDE_LINES, False)
        tree_gui_settings.SetBool(c4d.TREEVIEW_MOVE_COLUMN, True)
        tree_gui_settings.SetBool(c4d.TREEVIEW_RESIZE_HEADER, True)
        tree_gui_settings.SetBool(c4d.TREEVIEW_FIXED_LAYOUT, True)  # Don't allow Columns to be re-ordered
        tree_gui_settings.SetBool(c4d.TREEVIEW_ALTERNATE_BG, True)  # Alternate Light/Dark Gray BG
        tree_gui_settings.SetBool(c4d.TREEVIEW_CURSORKEYS, True)  # Process Up/Down Arrow Keys

        self._tree_gui = self.AddCustomGui(
            0,
            c4d.CUSTOMGUI_TREEVIEW,
            "",
            c4d.BFH_SCALEFIT | c4d.BFV_SCALEFIT,
            300,
            300,
            tree_gui_settings
        )

        return True

    def InitValues(self):
        """Set initial values when dialog is first opened."""

        tree_data = ObjectTree(self)
        self._tree_gui.SetRoot(None, tree_data, None)

        return True


# ====== COMMAND ====== #

class ObjectBrowserCommand(c4d.plugins.CommandData):
    """Command that opens a ObjectTree dialog."""

    dlg = None

    def Execute(self, doc):
        if self.dlg is None:
            self.dlg = ObjectBrowser()

        return self.dlg.Open(
            dlgtype=c4d.DLG_TYPE_ASYNC,
            pluginid=PLUGIN_ID,
            xpos=-1,
            ypos=-1,
            defaultw=300,
            defaulth=500
        )

    def GetState(self, doc):
        return c4d.CMD_ENABLED

    def RestoreLayout(self, sec_ref):
        if self.dlg is None:
            self.dlg = ObjectBrowser()

        return self.dlg.Restore(PLUGIN_ID, secret=sec_ref)

def main():
    """Register the plugin with Cinema 4D."""

    c4d.plugins.RegisterCommandPlugin(
        PLUGIN_ID,
        PLUGIN_NAME,
        0,
        None,
        PLUGIN_HELP,
        ObjectBrowserCommand()
    )

if __name__ == "__main__":
    main()