An event is a kind of action or activity in your daily life.
An record is an occurrence of the corresponding event. Record is inputted by user in the following effective way.
For every event, the user can choose whether it is with or without unit, and with or without duration, thus creating four categories of events.
For an event with duration, when it starts, a timer is automatically triggered; when it ends, the user clicks the end button and potentially input the value of the bound unit. Then the corresponding record with its duration and value of unit will be generated and stored.
Note: By long pressing the event, the user can manually input a former time as its starting or ending time. Simultaneous-running events are allowed ant all events' status will not be disrupted by terminating the app.
For an event without duration, we only care about its ending time. A short press adds a record of it with current time as the end time. To enter a former time as end time, a long press is needed. (Value of unites may be inputted depending on whether the event is bound with a unit).
