1. You can use Set Width to force width of the table. You might have to do some calculations to get it exactly what you wish it to be.
Names Default To Here(1);
dt = Open("$SAMPLE_DATA/Big Class.jmp");
nw = New Window("Example",
Button Box("Show Table",
Try(x << delete);
temp << append(x = Data Grid Box());
x << Set Data Table(dt);
x << Close Side Panels(1);
x << Set Width(420);
),
temp = V List Box()
);
2. You can keep it from getting smaller for example by preventing V List Box from auto-stretching (there are also other possibly better options)
Names Default To Here(1);
dt = Open("$SAMPLE_DATA/Big Class.jmp");
nw = New Window("Example",
Button Box("Show Table",
Try(x << delete);
temp << append(x = Data Grid Box());
x << Set Data Table(dt);
x << Close Side Panels(1);
),
temp = V List Box()
);
temp << Set Auto Stretching({0, 0});
-Jarmo