Mutation and update cache

Now let's do the integration part. Open TaskFragment.kt and add the following code to define the delete mutation

TaskFragment.kt

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    private fun removeTodoMutationCloud(todoId: Int){
        // Init Query
        removeTodoMutation = RemoveTodoMutation.builder().id(todoId).build()

        // Apollo runs query on background thread
        Network.apolloClient.mutate(removeTodoMutation)?.enqueue(object : ApolloCall.Callback<RemoveTodoMutation.Data>() {
            override fun onFailure(error: ApolloException) {
                Log.d("Todo", error.toString() )
            }

            override fun onResponse(@NotNull response: Response<RemoveTodoMutation.Data>) {
                // get data from local cache and update the list
                val index = listItems?.indexOfFirst { todo ->  todo.id() == todoId}
                var todos = (listItems?.toMutableList())?.removeAt(index!!)

                Network.apolloClient
                    .apolloStore()
                    .write(GetMyTodosQuery(), GetMyTodosQuery.Data(mutableListOf(todos))).execute()
                getMyTodosQueryLocal()
            }
        })
    }

We have a function defined to handle the onClick of delete icon to remove a todo. Let's update the function.

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 override fun delete(taskId: Int) {
-        // Todo : Method for deleting a task
+        removeTodoMutationCloud(taskId)
    }