[Lazarus] Docking manager implementation

[Hans-Peter Diettrich]

Graeme Geldenhuys schrieb:

> Percentages is often used in designing a layout. View some websites
> HTML source or CSS files.  So why can't that be applied to "real" GUI
> programming as well.

Percentages are easy to implement, but hard to use. Too bad if a layout 
system doesn't offer some better method.

Imagine a table, where all the column widths (in percents) have to be 
recalculated whenever a column is inserted or removed. Who should do 
that calculation, the user or the system?

With proportional sizing one can have e.g. columns of width=1, double 
wide columns of width=2, and margins of width=0.1, and the layout 
manager will do the rest :-)

DoDi