Alternation edge

Click on the alternation edge button on the Class graph toolbar. When the mouse pointer is on the drawing canvas its shape changes to crossbar shape. Press mouse button down on the source class and drag the mouse in the pressed position to the destination class and release the mouse button. APStudio allows only one bend point in an edge. If user wants to bend the edge while drawing, stop dragging the mouse at the bendpoint and again start drawing by clicking the mouse down and dragging it to the destination class. Source and destination can not be same. Also multiple inheritance is not allowed. If only one of the connected classes is alternation class then the user can start drawing from any class.