[SalesForce] How to display fields of an Object record in one column (one below other) in a visualforce page

On keypress/keydown/change of your inputFields (whichever you prefer) you should call an action function to sync values. The idea is to pass along which field you're updating, and which record to sync from, and loop through your records to identify selected records and update the proper field. This may be a bit clunky but I hope I'm conveying the idea appropriately.

<apex:actionFunction name="sync" action="{!sync}">
    <apex:param name="field" assignTo="fieldToUpdate" value="" />
    <apex:param name="value" assignTo="selectedId" value="" />
</apex:actionFunction>

<!-- using i as an example for your table values -->
<apex:inputField value="{i.Phone}" onChange="sync('phone', '{i.Id}')" />



List<WrapperObject> WrappedObjectList = (however you fill your list);

public string fieldToUpdate {get;set;}
public string selectedId {get; set;}
public string fieldValue{
    get{
        //grab the value from the selected object
        for(WrappedObject o : WrappedObjectList){
            if(o.Id == selectedId){
                if(fieldToUpdate == "phone"){
                    return o.Phone;;
                }
            }
        }
        return "";
    }
}

public PageReference sync(){
    for(WrappedObject o : WrapperObjectList){
        //update all selected objects with that value
        if(o.Selected){
            if(fieldToUpdate == "phone"){
                o.Phone = fieldValue;
            }
        }
    }
    return null;
}

Hope this helps! c:

It can be done using client side javascript. To get exact Id of the element, you can use "Inspect Element" option in chrome. Basically salesforce will add the entire path of parent apex elements in the ID of child element. For example check sample code below,

<apex:page id="page">
    <apex:form id="form">
        <apex:pageblockTable id="table">
            <apex:inputField value="{!testvalue}" id="field"/>
        </apex:pageblockTable>
    </apex:form>
</apex:page>

It will result in final Id of the field as

page:form:table:field

instead of simple "field". If you are using rerender on the field using apex tags, you can directly use Id "field". But if you are using javascript, you need to use the full ID, which is the actual Id.