You might add one black pixel column between
the vertical axis bar and the first green bar.
You are showing (as it works out on this phone's screen)
4 green bars, and a wider space, which is fine.
Your current version shows 3 groups of 5 already.
However, in optimizing for this screen resolution,
if one wanted to even bother, you could show groups of 5
bars, then an extra space, to match the tic marks, and save
a couple of pixels. Since the wider spaces appear because
of floating to integer conversion, just removing a few pixels
from the width of the plot should make the spacing
become 5 bars instead of 4 bars.
I believe that you want to add additional screens, and
a Navigation button could be Index, going to a set of
GoTo Screen buttons. So, see below...
Eventually the two buttons and Connected status box
could be not drawn on this screen, giving more room
to use for making a readable display.
Then, when the screen is touched (not in the upper icon area)
the control/navigation buttons could appear, quickly
overlaying the current data screen.
These Navigation buttons might include Prev and Next
to get through a series of data screens, but there might
be an "index" ("Go To... ") button that goes to a screen of
buttons that go directly to the desired data screens.
So, tap for Control, like Start and Stop, Settings, and
Index (or GoTo), then a second tap on GoTo (or Index),
and a third tap taking one to the desired data screen,
usually showing the "old" data, so the user could
study the same data as displayed several different
Another Control button would be Re-Request, or Update,
or some such that would re-Request the data for the
current screen, or set of screens. Perhaps a future
feature would be auto-request every N seconds, but
that should NOT be the default, for liability reasons.
The writing of a Request to the CAN bus is then entirely
done at the user's request, either once manually (the
power-On default of N = 0), or periodically, but only
after being specifically set up by the user.
Screens that just use passive listening reading of the
CAN bus can be updated as often as the messages
and data-processing allows.
The Connected status might be done with the system
Bluetooth icon, which looks dimmed on your screen.
But, the system might have other icons available,
or you could make one for your own, and put it in an
See SOC/GID-Meter and CAN-Do Info
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