onBeforeConditionSet

fires before a new condition for cells has been set

boolean onBeforeConditionSet(number row,number column,array oldCondition,array newCondition, [string page] );

row

numberthe ID of the row column

numberthe ID of the column oldCondition

arraythe old condition for cells newConditionarraythe new condition for cells pagestringthe name of the sheet

boolean

returning false will prevent the new condition setting

$$("spsheet1").attachEvent("onBeforeConditionSet",function(row,col,oCond,nCond,page){
    // handler code here
    return true;
});

Details

The event is not called for pasting copied data. Use onBeforePaste instead.