Is there a way to change the height of VolumePane from the code?
I would like to make VolumePane the same height as PricePane.

I see that you've already found what you're looking for:

Number of decimals

Because this is the way to go.

So the answer is "No, there is no programmable way to change the height of the volume pane"?

There is no documented way. Attempts at working around this fail as you can see:

CODE:
Please log in to see this code.

Yes, I saw them to fail as read only.

The VolumePane looks great but it's just too narrow to see when having many chart windows open.

QUOTE:
Is there a way to change the height of VolumePane from the code?

You can change its height manually.

I have more than 30 ETF chart windows opened by a workspace and manual operation isn't practical for me.
I need to monitor the intra-day volume movement but VolumePane is too small and decimals make hard to read the numbers.

Since you're using a workspace, this is going to be just a one-time inconvenience.

As an undocumented and unsupported alternative, you can edit the workspace file, adding a new line like below to each ChartForm section:

CODE:
Please log in to see this code.

The "P=50" stands for PricePane and "V=100" stands for the VolumePane height. "RSI" is an example of an indicator pane.

It seems causing an exception.

QUOTE:
Type=ChartForm
Bounds=793,0,793,424
Version=8
ItemCount=23
V=100
TrendFollow
SPY
.
.

This one line "V=100" in the workspace file causes an exception below.

QUOTE:
************** Exception Text **************
System.IndexOutOfRangeException: Index was outside the bounds of the array.
at WealthLabPro.MainForm.b(String A_0)
at WealthLabPro.MainForm.cu(Object A_0, EventArgs A_1)
at System.Windows.Forms.Form.OnLoad(EventArgs e)
at System.Windows.Forms.Control.CreateControl(Boolean fIgnoreVisible)
at System.Windows.Forms.Control.CreateControl()
at System.Windows.Forms.Control.WmShowWindow(Message& m)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.Form.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

Did I say unsupported and undocumented? This means you're experimenting with this on your own.

1. Try my line, it did work on my end (your one is partial).
2. Do a fresh save and experiment with your own line.

Yes, you said and I experimented but I couldn't figure out the exception so I was just hoping if you know something about it.

1. I did it at the very first and got an exception. That's why I simplified it to just VolumePane but still got an exception.
2. I will experiment it more and get back to you.

Maybe it's the position of the line inside the file that counts (serialization expects it to find it at some precise location).