Pervasive programs should be context-aware, which means that program functions should react according to changing environmental conditions. Slicing, as an important class of code analysis techniques, can clarify the dependence between program artifacts and observable system states to facilitate debugging, testing, and other analyses. Existing program slicing techniques, however, do not take the contextual environment into account, resulting in incomplete slices for such kind of program. To tackle this problem, this paper proposes a novel static slicing approach. It develops a graphic representation that captures the contexttriggered invocations and the pervasive concurrency features. We have also developed an algorithm to check the propagation dependence in processing inter-thread data dependence. Further optimizations are discussed.