Add keybinds to scroll page up/down

TODO.md

@@ -11,7 +11,10 @@
   - When qml syntax highlighting supports ES6 string interpolation, use them
 
 - Fixes
+  - alt+n
   - Icons on KDE
+  - Backspace bug
+  - Add missing shortcuts to config file
 
   - Show error if uploading avatar fails or file is corrupted
 
@@ -25,6 +28,8 @@
   - Terrible performance using `QT_QPA_PLATFORM=wayland-egl`, must use `xcb`
 
 - UI
+  - Just use Shortcut onHeld instead of analyzing the current velocity
+    in `smartVerticalFlick()`
   - Reduce icons brightness
     - Thinner expand arrow
   - Restore previous focus after closing right click context menu

src/python/config_files.py

@@ -111,8 +111,10 @@ class UISettings(JSONConfigFile):
                 "startDebugger":    ["Alt+Shift+D"],
                 "reloadConfig":     "Alt+Shift+R",
 
-                "scrollUp":         ["Alt+Up", "Alt+K"],
+                "scrollUp":       ["Alt+Up", "Alt+K"],
-                "scrollDown":       ["Alt+Down", "Alt+J"],
+                "scrollDown":     ["Alt+Down", "Alt+J"],
+                "scrollPageUp":   ["Alt+Ctrl+Up", "Alt+Ctrl+K", "PageUp"],
+                "scrollPageDown": ["Alt+Ctrl+Down", "Alt+Ctrl+J", "PageDown"],
 
                 "focusSidePane":    ["Alt+S", "Ctrl+S"],
                 "clearRoomFilter":  ["Alt+Shift+S", "Ctrl+Shift+S"],

src/qml/Shortcuts.qml

@@ -32,6 +32,23 @@ HShortcutHandler {
         onHeld: pressed(event)
     }
 
+    HShortcut {
+        sequences: settings.keys.scrollPageUp
+        onPressed: Utils.smartVerticalFlick(
+            flickTarget, -2.3 * flickTarget.height, 10,
+        )
+        onHeld: pressed(event)
+    }
+
+    HShortcut {
+        sequences: settings.keys.scrollPageDown
+        onPressed: Utils.smartVerticalFlick(
+            flickTarget, 2.3 * flickTarget.height, 10,
+        )
+        onHeld: pressed(event)
+    }
+
+
     // SidePane
 
     HShortcut {