Add basic cursor tree widget

cheuph/cursor_tree_widget.py

@@ -0,0 +1,48 @@
+import datetime
+import time
+from typing import Tuple, TypeVar
+
+import urwid
+
+from .attributed_lines_widget import AttributedLinesWidget
+from .cursor_rendering import CursorTreeRenderer
+from .element import Element, Message
+
+__all__ = ["CursorTreeWidget"]
+
+E = TypeVar("E", bound=Element)
+
+class CursorTreeWidget(urwid.WidgetWrap):
+    """
+    This widget draws a CursorTree and moves the cursor around.
+    """
+
+    def __init__(self, tree: CursorTreeRenderer[E]) -> None:
+        self._tree = tree
+        self._lines_widget = AttributedLinesWidget()
+        super().__init__(self._lines_widget)
+
+    def render(self, size: Tuple[int, int], focus: bool) -> None:
+        width, height = size
+
+        self._tree.render(width, height)
+        self._lines_widget.set_lines(self._tree.lines)
+
+        return super().render(size, focus)
+
+    def selectable(self):
+        return True
+
+    def keypress(self, size: Tuple[int, int], key: str):
+        if key == "shift up":
+            self._tree.scroll(-1)
+        elif key == "shift down":
+            self._tree.scroll(1)
+        elif key == "shift right":
+            self._tree.scroll_horizontally(1)
+        elif key == "shift left":
+            self._tree.scroll_horizontally(-1)
+        else:
+            t = datetime.datetime(2019,5,7,13,25,6)
+            self._tree._supply.add(Message(str(time.time()), None, t, "key", key))
+            self._invalidate()