android - 如何使用 SavedStateHandle 为 Android ViewModel 编写单元测试

Question

在 Android ViewModel 中，如何编写单元测试来验证 savedStateHandle 是否正确保存和恢复值？

class SampleViewModel(
    private val savedStateHandle: SavedStateHandle
) : ViewModel() {
    var foo: Int = 0 // In the actual code, foo is a non-parcelable type

    init {
        savedStateHandle.get<Int>("foo")?.let {
            foo = it
        }

        savedStateHandle.setSavedStateProvider("foo") {
            bundleOf("foo" to foo)
        }
    }
}

Answer 1

如果您的问题是如何创建 SavedStateHandle，您可以像这样在单元测试中创建并传递它:

val savedStateHandle = SavedStateHandle()
// or actually pass data with:
// SavedStateHandle(mapOf("foo" to 0))

val viewModel = SampleViewModel(
    savedStateHandle = savedStateHandle
)

然后，您可以通过调用简单地检查该值是否已设置

assert(savedStateHandle.get<Int>("foo") == 0)