Bug 496804

Created attachment 176199 [details]
screencast

While testing LabPlot I encountered a minor but annoying issue:

in many places
1. the default spinbar step sizes are not sensible (they use the last digit)
2. the default decimals are not sensible

One example is bug 496803. But there are more. Take for example the Legend property and there General and geometric (see attached screencast):
1. you quickly want to change the value thus click on the spinbar arrow button, but as result you get a change of 1e-4%. In effect using the arrow button makes then no sens and the button could be omitted
2. you get 4 decimals for a percentage. This is not a good UI. The user should only see by default sensible decimal places. For a percentage these are 2 decimals (unless the user set e.g. to get always 3 decimal)

I propose to revise all settings UI spinbars to adjust the default decimals and the default stepsize. My experience (with programming fro LyX and FreeCAD) is:
* default decimals: 2, except of special uses cases like e.g. output of sin/cos() values or explicit decimal settings the user made in the preferences
* default stepsize: so that the range the user will need to address on 90% of the cases can be accessed with max. 20 button clicks. For example if a typical range would be between 0 and 20 %, the stepsize should be 1, of the typical range is between -5 and 5 cm, the stepsize is 0,5 cm

This is an annoying issue because the workflow is slowed down since one has to move the hand from the mouse, cannot "just click", has to enter values via the keyboard.

If I manage to compile LabPlot under Windows, I could do this and send PRs.