Power button

The power button switches the CrossPad on and off, and it is also the back button. A short click steps back one level. A longer hold moves the encoder to the transport or switches the CrossPad off. The timing is the same in every app.

Click or hold

What you do	How long	What happens
Click	let go within 0.5 s	Back, one step (see below).
Hold	0.5 s	The encoder jumps to the transport keys at the top of the screen. Hold again to jump back.
Hold	4 s	The CrossPad switches off. Set the time in Settings → System → Power Long-Press (1 to 4 s).
Hold, on battery	7 s	Ship mode: the battery is disconnected for storage or shipping. See Get started.
Hold while off	about 1.5 s	The CrossPad switches on.

In the PC simulator, Space or Ctrl is the power button: tap it for a click, hold it for a hold.

What a click closes

A click closes the first of these that is open, and only that one:

1. An open dropdown list.
2. A dialog or overlay, the newest first.
3. A value you are changing with the encoder.
4. The encoder’s place on the transport keys: it goes back to the screen it came from.
5. The running app: the app’s own back step first. An app without one closes.

On the MODE map a click has nothing left to close.

Rules for app authors

• An app with levels of its own (a settings screen with sub-pages, a wizard) sets a back handler with setOnBack() in its create function. The handler steps back one level and returns true. On the app’s top level it returns false, and the app closes.
• A layer that opens over the app, such as a file browser over an editor, registers itself with ui_back_push(fn, user) when it opens and calls ui_back_remove(token) from its delete event. Each click then closes exactly one layer, the newest first. Use setOnBack() for the app’s own levels and the stack for layers you create on the fly.
• To give the encoder back to a group you saved, call lv_indev_restore_group(indev, saved) from crosspad-gui widgets/gui_helpers.h. It checks that the group still exists and leaves the encoder alone when it does not. Always restore a saved group this way, never by writing the pointer back directly.