The row layout manager orders the controls in lines or rows.
The row layout manager calculates the necessary space for the different controls, and establishes the amount of rows that will be occupied according to the size. The calculated size is on the basis of complete rows, in other words, if a control occupies 1.5 rows, then the row layout manager will assign 2 complete lines to it. (Figure 1)
Figure 1 - Big component added
The row layout manager orders the controls sequentially as they are added, thus the first element will occupy row one.
Figure 2 - Control added
When a control is eliminated, the lines occupied by the control are crossed, and the controls are ordered on the basis of their previous position. (Figure 3)
Figure 3 - Control from figure 1 deleted