Parent item 1 (initially unchecked)
Parent item 1 (initially unchecked)
Sub item 1
Sub item 2
Sub item 3
Parent item 2 (initially mixed)
Parent item 2 (initially mixed)
Sub item 4
Sub item 5
Sub item 6
Parent item 3 (initially all checked)
Parent item 3 (initially all checked)
Sub item 7
Sub item 8
Sub item 9