Implement Prev Sib for Displays

[pauldeen]

When buidling a display tree in a new window I cannot traverse the tree in reverse direction. So I can use number edit box << sib to find the next display box, but I cannot use <<prev sib to find the previous display box.

Example of what I'm trying to do in this forum topic:  

[Jeff_Perkinson]

JMP 15 has a <<Prev Sib() message.

Names Default To Here( 1 );
//This message applies to all display box objects
dt = Open( "$SAMPLE_DATA/Big Class.jmp" );
biv = dt << Bivariate( y( :weight ), x( :height ) );
rbiv = biv << report;
axisbox = rbiv[axis box( 2 )];
axisSibling = axisbox << Prev Sib();
Print( axisSibling << Class Name() );