retrieving specific items from an ArrayList

Question

I am really struggling with how to obtain the index of an object in an array list via a specific property value of said object. If anyone could provide me with a method for how to do this, it would be VERY much appreciated. I have an array list that contains several task objects. These objects can have a status of active, inactive, held, alerting, etc. If I have 3 task objects in my arrayList like the ones below... index0 = task.alerting index1 = task.active index2 = task.held How can I cycle through the array list looking for the one with a state of alerting??? Please help. Thank you. Bob