Hi All,

             I am trying to collect a value of the selected checkbox, am new to visualforce.

<apex:page controller="chooseColor">
    <apex:form id="Form1" >
    <script type="text/javascript">
        function ToggleInput(theId)
            {
                var e = document.getElementById(theId);
                alert(e.value);
            }
        function ToggleInput2(Idd)
            {
                var e = document.getElementById(theId);
                alert(e.value);
            }

    </script>
    
<apex:selectList id="chooseColor" value="{!string1}" onchange="ToggleInput('{!$Component.chooseColor}');">
    <apex:selectOption itemValue="red" itemLabel="Red"/>
    <apex:selectOption itemValue="white" itemLabel="White"/>
    <apex:selectOption itemValue="blue" itemLabel="Blue"/>            
</apex:selectList>

<apex:selectCheckboxes id="chooseColor1" value="{!string1}" onchange="ToggleInput2('{!$Component.chooseColor1}');">
    <apex:selectOption itemValue="red" itemLabel="Red" id="ID1" title="1"/>
    <apex:selectOption itemValue="white" itemLabel="White" id="ID2" title="2"/>
    <apex:selectOption itemValue="blue" itemLabel="Blue" title="3"/>            
</apex:selectCheckboxes>  

    </apex:form>
</apex:page>

 Apex Controller Code:

public class chooseColor {
    String s = 'blue';
    public String Val{get;set;}
 
    public String getString1() {
        return s;
    }
                        
    public void setString1(String s) {
        Val = s;
        system.debug('Value+++'+Val);
        this.s = s;
        
    }
}

 When i try the apex:selectList am getting proper values, but am getting undefined for apex:selectCheckbox tag's. Please tell me where i have done the mistake.

else tell me how to find the selected checkbox. I have three checkbox and am selecting only two, i need to find the selected checkbox alone. give some idea.

Thanks in advance.. :)