How to get sliders in a row in manipulate?

Question

Manipulate[v + t, {v, 0, 1}, {t, 0, 1},
           ControlPlacement -> Left, ControlType -> VerticalSlider]

puts the second slider below the first one. How to get it on the left of the first?

Answer 1

1. You can wrap each control with Control and use them with Row:

Manipulate[v + t, Row[{Control@{v, 0, 1}, Control@{t, 0, 1}}], 
 ControlPlacement -> Left, ControlType -> VerticalSlider]

2. Alternatively, you can use the Method option to modify the setting for the suboption "ControlAreaDisplayFunction" to organize the control area content as you like:

Manipulate[v + t, {v, 0, 1}, {t, 0, 1}, ControlPlacement -> Left, 
 ControlType -> VerticalSlider, 
 Method -> "ControlAreaDisplayFunction" -> 
   (Row[Column[#, Alignment -> Center] & /@ #[[1]], Spacer[10]] &)]

Answer 2

In this answer I introduced a function copyCurve which returned a manipulator containing a number of sliders and other interactive elements organized in rows and columns like in the image below:

Just have a look. Have fun!