How to scroll half a page in macOS via keyboard/mouse that is similar to trackpad functionality?

Question

I am no longer using the trackpad on my MacBook and using a separate wired Apple keyboard instead. I miss the scrolling functionality on my trackpad, I'm having to make do with the keyboard (the mouse is too far away for efficient scrolling).

Is there a way to map a key combination (such as cmd+pagedown) such that I scroll up/down half a page instead of a full page?

Even better, is there a way to map key combinations to arbitrary scrolling distances?

Answer 1

I have no idea why it hasn't been answered for so long, but there is a way - you can do it using ControllerMate. It's an overkill, that's for sure (and it costs $25), but it does do the job.

In a nutshell: Open ControllerMate, create a new page in "Programming items" section. In Palette, open "Controllers" (⌥⌘1), choose your keyboard and press the key you want to bind the action to (for example, Cmd key). It will highlight there.
If you want to group several keys (such as Cmd+Pagedown), drag the second (third... nth...) key there too and connect them using "AND" operator in "Logic" (⌥⌘4) palette. Then use the "Scroll Wheel Building Block" in an "Output" (⌥⌘2) palette. You can customize the scrolling step in the "Inspector" window.

You will end with something like that:

Do the same for the Cmd+PageUp hotkey (don't forget to change the direction of scrolling).

Answer 2

I am using Keyboard Maestro to do this.

There is a system macro called "Simulate Scroll Wheel Down X pixel" where you can define X for how much you wanted one key press to scroll. I use 720 which is about half a page.

Keyboard Maestro can let you make this system wide or, in my case, I limited this to just Safari and Chrome.

Answer 3

Setting up a custom shortcut in BetterTouchTool to scroll half a page involves creating a gesture or keyboard shortcut that triggers a predefined scrolling action. Here’s how you can set this up using BetterTouchTool, a powerful tool for customizing input devices on macOS:

Step 1: Install BetterTouchTool

If you haven't already installed BetterTouchTool, download it from the official website and install it on your Mac. BetterTouchTool is not free, but it offers a trial period to test its features.

Step 2: Open BetterTouchTool

• Launch BetterTouchTool from your Applications folder or Spotlight.
• You'll see the main window where you can configure gestures and shortcuts.

Step 3: Choose Your Device

• Select the device you want to create the shortcut for (Trackpad, Mouse, Keyboard, etc.) from the tabs at the top of the BetterTouchTool window.

Step 4: Add a New Gesture or Shortcut

• For a Trackpad or Magic Mouse: Click on the “+ Add New Gesture” button.
  • Choose a gesture. For example, select “Two Finger Swipe Up” or any gesture you prefer.
• For a Keyboard: Click on the “+ Add New Shortcut” button.
  • You can then press the key combination you want to use for this action.

Step 5: Assign the Action

• In the action search bar, type “Scroll” to find scrolling actions.
• Select “Custom Scroll” from the list of actions.
  • You need to set the vertical scroll amount. Since there's no preset for "half a page," you will need to experiment with the number. Start with values like 300 or 500 and adjust based on your preference and screen size.

Step 6: Adjust the Scrolling Speed and Smoothness

• After setting the scroll action, you might want to adjust the speed and smoothness of the scroll. BetterTouchTool allows you to refine these in the action settings, providing sliders to adjust speed and other parameters.

Step 7: Test Your Shortcut

• Use your new gesture or shortcut in an application that scrolls (like a web browser or PDF viewer) to see how it works.
• If the scrolling is too much or too little, adjust the scroll amount in BetterTouchTool until it feels like half a page to you.

Step 8: Save and Optimize

• Once you find the right settings, make sure to save your configuration.
• You can also make profiles specific to applications in BetterTouchTool, which allows your half-page scroll to behave differently depending on the app you are using.

Additional Tips:

• Experiment with different gestures or shortcuts to find what is most comfortable for you.
• Use BetterTouchTool’s advanced settings to trigger the gesture or shortcut only under specific conditions or within specific applications, enhancing your workflow.

BetterTouchTool is highly customizable, and part of getting it right is experimenting with settings until you achieve the desired behavior. This flexibility allows you to fine-tune how you interact with your Mac, making tasks like scrolling more efficient.