i have a question, been stuck for a while, 
i dont know how can i add a checkbox in the list, for example if I have a list of items i want to be able to check them. my xml code is the following:

```
<LinearLayout android:id="@+id/topLayout"
    android:orientation="vertical" android:layout_width="fill_parent"
    android:layout_centerHorizontal="true"  android:layout_height="wrap_content">

</LinearLayout>

<LinearLayout
    android:id="@+id/middleLayout"
    android:orientation="horizontal"
    android:layout_height="wrap_content"
    android:layout_width="fill_parent">

    <LinearLayout android:id="@+id/leftMiddleLayout"
            android:orientation="vertical" android:layout_below="@+id/topLayout"
            android:layout_above="@+id/bottomLayout"
            android:layout_width="60px" android:layout_height="wrap_content"
            >

            <ListView android:id="@+id/checkboxList" android:layout_width="fill_parent"
                    android:layout_height="wrap_content" ></ListView>

            <CheckBox android:id="@+id/checkbox"
            android:layout_width="wrap_content" android:layout_height="wrap_content"
            android:checked="false"
            android:text="test">
            </CheckBox>

    </LinearLayout>

    <LinearLayout android:id="@+id/rightMiddleLayout"
            android:orientation="vertical" android:layout_below="@+id/topLayout"
            android:layout_above="@+id/bottomLayout"
            android:layout_width="280px" android:layout_height="wrap_content"
            >

            <ListView android:id="@+id/list" android:layout_width="fill_parent"
                    android:layout_height="wrap_content" ></ListView>

            <TextView android:id="@+id/text" android:layout_width="fill_parent"
                    android:layout_height="wrap_content"/>                   
    </LinearLayout>
</LinearLayout>

<LinearLayout android:id="@+id/bottomLayout" 
    android:layout_alignParentBottom="true" 
    android:orientation="horizontal" 
    android:layout_width="fill_parent" android:layout_height="wrap_content"
    android:paddingBottom="5pt"
    >

    <EditText android:id="@+id/insertNewItem"
        android:layout_width="220px" android:layout_height="wrap_content" />

    <TextView android:layout_width="10px" android:layout_height="wrap_content" />

    <Button android:id="@+id/addItemButton" android:layout_width="wrap_content"
        android:layout_height="fill_parent" android:text="Add Item"/>
</LinearLayout>

```

if you have any ideas please let me know, its for my academic studies :((

Thank you!