Chen,

>I have four biz objects having a relationship as: parent -> child -> grandchild -> great-grandchild. They are bound to four grids spread over three tabPages. The relationship chain is established with RegisterChildBizObj(). I have codes in HookParentRetrieved() and HookParentNavigated() to call my methods to get the datasets.
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>When the form is run, I can get the initial sets of datasets in the grids. However, if I move up and down in, say, the child grid, the grandchild and greatgrandchild grids remain unchanged. I also tried to add navigation control to the form, but depending on which grid I associate the navigation control to, the grids behave differently.
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>After consulting the Dev Guide, I still don¡¯t know what I did wrong. It seems, if I don't have more than two grids, the way I do things work fine.

If you set a breakpoint in the grandchild and great-grandchild business object's hook methods, do these methods ever fire?

Regards,