锁屏d ds

private final IDevicePolicyManager mService;

mService = IDevicePolicyManager.Stub.asInterface(
                ServiceManager.getService(Context.DEVICE_POLICY_SERVICE));

if (mService != null) {
            try {
                mService.lockNow();
            } catch (RemoteException e) {
                Log.w(TAG, "Failed talking with device policy service", e);
            }
}