Power and Device Awareness
Mobile PC users consistently cite battery life as their most critical mobile computing concern. Any long-time mobile PC user can recall stowing the PC in its carrying case, expecting the computer to go to sleep, only to later find it running, overheated, and with a depleted battery. Or, they can recall travel layovers, in which a primary concern was not rest or refreshment, but finding an AC power outlet to recharge the battery before the next flight.
Power management does not solely concern battery life, however. Improving power management also reduces energy costs and benefits the environment.
Windows Vista introduces significant improvements in power management. Users benefit from simplified power management options, and default settings conserve power. The shutdown experience has also been streamlined. For example, a new power button on the Start menu provides a quick way for users to put mobile PCs to sleep. And a new powersaving mode called Fast S4, which combines sleep and hibernate, is available on desktop computers.
For developers, Windows Vista introduces stricter rules about sleep transitions and shutdown. The overall goal is to provide a faster and more predictable startup and shutdown experience for users.
A good place to get started is the "Power Awareness in Windows Vista (C#, Windows Vista Version)", hands-on lab, found on line with the Mobile PC and Tablet PC Hands-On Labs.
At minimum, your application should do the following:
- Properly handle sleep transitions and avoid delaying the transition from idle to sleep.
- Modify application behavior to maximize either power or performance, based on the power plan in use.
- Monitor and respond to system messages about power management status.
Topics in this section
- Managing Power in Windows Vista
- The Power-Aware Application
- Reducing Power Consumption
- Grab-and-Go Docking Guidelines
Build date: 2/8/2011