Merge pull request #44 from VPerrollaz/add-vi-move

Add some vi-style navigation to the pager.

README.md

@@ -147,7 +147,7 @@ rich "Hello [b]World[/b]!" --rule --rule-style "red" --rule-char "="
 
 Add `--pager` to display the content with a built in pager application.
 
-Scroll the pager with cursor keys, page up/down, home, end. Alternatively use the scrollbar which will be visible to the right of the terminal.
+Scroll the pager with cursor keys, page up/down, home, end. Alternatively use the scrollbar which will be visible to the right of the terminal. Or use the vi navigation (j, k, ctrl_d, ctrl-u).
 
 ```
 rich __main__.py -n -g --theme monokai --pager

src/rich_cli/pager.py

@@ -59,8 +59,18 @@ async def on_load(self, event: events.Load) -> None:
         await self.bind("q", "quit", "Quit")
 
     async def on_key(self, event: events.Key) -> None:
-        if event.key == " ":
+        if event.key == "j":
+            self.body.scroll_up()
+        elif event.key == "k":
+            self.body.scroll_down()
+        elif event.key == " ":
             self.body.page_down()
+        elif event.key == "ctrl+u":
+            self.body.target_y -= self.body.size.height // 2
+            self.body.animate("y", self.body.target_y, easing="out_cubic")
+        elif event.key == "ctrl+d":
+            self.body.target_y += self.body.size.height // 2
+            self.body.animate("y", self.body.target_y, easing="out_cubic")
 
     async def on_mount(self, event: events.Mount) -> None:
         self.body = body = ScrollView(auto_width=True)