Make serial plotter ringbuffer size configurable

[chromhelm]

No description provided.

[facchinm]

@ArduinoBot build this please

[ArduinoBot]

✅ Build completed.

Please test this code using one of the following:

⬇️ http://downloads.arduino.cc/javaide/pull_requests/arduino-PR-7454-BUILD-747-linux32.tar.xz
⬇️ http://downloads.arduino.cc/javaide/pull_requests/arduino-PR-7454-BUILD-747-linux64.tar.xz
⬇️ http://downloads.arduino.cc/javaide/pull_requests/arduino-PR-7454-BUILD-747-windows.zip
⬇️ http://downloads.arduino.cc/javaide/pull_requests/arduino-PR-7454-BUILD-747-macosx.zip
⬇️ http://downloads.arduino.cc/javaide/pull_requests/arduino-PR-7454-BUILD-747-linuxarm.tar.xz

ℹ️ The linuxarm build is still experimental and may not be always available.

[madsdyd]

Just a note for others, and to stop myself from keep opening this issue: The PR (I think this should have been in the description):

Contains code to add a spinner to the Serial Plotter GUI, that allow to change the number of retained data points from the existing fixed 500 to a user chosen value between 10 and 5000.

However, the quality check fails, because there is:

• An unused local variable legendLenght in paintComponent
• The method setNewBufferCapacity assigns a new value to its parameter.

Both of these should be trivial to fix, but are there any maintainer (person with write access) that would be willing to merge this change?

[madsdyd]

So, does #7461 actually contain all the code in this issue as well?

[chromhelm]

Do not pull it yet. I have made faulty merge.

[per1234]

This partially fixes arduino/arduino-serial-plotter-webapp#29 (and the remaining part may be wontfix)

[CLAassistant]

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2 out of 3 committers have signed the CLA.

✅ chromhelm
✅ facchinm
❌ Wilhelm Wiens

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