start

The blocker ID that is assigned to this power blocker.

Starts preventing the system from entering lower-power mode. Returns an integer identifying the power save blocker.

Note: prevent-display-sleep has higher precedence over prevent-app-suspension. Only the highest precedence type takes effect. In other words, prevent-display-sleep always takes precedence over prevent-app-suspension.

For example, an API calling A requests for prevent-app-suspension, and another calling B requests for prevent-display-sleep. prevent-display-sleep will be used until B stops its request. After that, prevent-app-suspension is used.