Hi Monika,
To bring the connector over node use order commands. By using the order commands or changing the z index of the connector we can able to bring the connector over the node. Select the connector and call diagram public API method BringToFront or through context menu order commands call Bring to front. So that connector come front all over the node and it does not gets hide under the nodes. We have attached a video demonstration that how to use bring to front method.
For more information about z order commands and context menu please refer to below UG link
For your information, please find the Z-order index behavior in our diagram control.
While loading or deserialzing the diagram elements or during automatic layouting, we used to render all the nodes and then the connectors. In this case, all the connectors will be having the higher z-index value than all the nodes. All the connectors will be positioning above the nodes.
When creating dynamically through interaction, drag and drop from stencil, or clipboard, we set the z-index value for every element.
For example:
1) First element – consider it as node – its z-index value is set as 0
2) Second element – consider it as connector – its z-index value is set as 1
3) Third element – consider it as connector – its z-index value is set as 2
Likewise, zindex value will be increment for each diagram element (node or connector) in the order of addng into the diagram surface.
Regards
Aravind Ravi