how to colapse and expand tabs dynamically in ms cmr 2011

we can collapse or expand the tabs in design mode by clicking the checkbox expand this tab by default as high lighted in image.

this also can be done dynamically as follows
1. get the tab object
var objTab = Xrm.Page.ui.tabs.get("<tabName>");
2.now call the expand and collapse state
objTab.setDisplayState("expanded"); // to expand
objTab.setDisplayState("collapsed"); // to collapse

hope this helps...

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