remove and query fences

MainActivity.kt

    fun onClick_button_remove(view: View?) {
        removeFences()
    }

    private fun removeFences() {
        Awareness.getFenceClient(this).updateFences(
                FenceUpdateRequest.Builder()
                    .removeFence(myPendingIntent)
                    .build()
            )
            .addOnSuccessListener {
                val timestamp = Timestamp(System.currentTimeMillis())
                val text = "[Fences @ $timestamp] Fences were successfully removed.".trimIndent()
                textViewMain.text = text + "\n" + textViewMain.text
            }
            .addOnFailureListener { e ->
                val timestamp = Timestamp(System.currentTimeMillis())
                val text = "[Fences @ $timestamp] Fences could not be removed: ${e.message}".trimIndent()
                textViewMain.text = text + "\n" + textViewMain.text
            }
    }

    fun onClick_button_query(view: View?) {
        queryFences()
    }

    protected fun queryFences() {
        Awareness.getFenceClient(this).queryFences(FenceQueryRequest.all())
            .addOnSuccessListener { fenceQueryResponse ->
                var fenceInfo = ""
                val fenceStateMap = fenceQueryResponse.fenceStateMap
                for (fenceKey in fenceStateMap.fenceKeys) {
                    val state = fenceStateMap.getFenceState(fenceKey).currentState
                    fenceInfo += "$fenceKey: ${if (state == FenceState.TRUE) "TRUE" else if (state == FenceState.FALSE) "FALSE" else "UNKNOWN"}".trimIndent()
                }
                val timestamp = Timestamp(System.currentTimeMillis())
                val text = "[Fences @ $timestamp]> Fences' states: ${if (fenceInfo == "") "No registered fences." else fenceInfo}".trimIndent()
                textViewMain.text = text + "\n" + textViewMain.text
            }
            .addOnFailureListener { e ->
                val timestamp = Timestamp(System.currentTimeMillis())
                val text = "[Fences @ $timestamp] Fences could not be queried: ${e.message}".trimIndent()
                textViewMain.text = text + "\n" + textViewMain.text
            }
    }