Generify periodically refreshing live data

4 files changed, 70 insertions, 48 deletions

diff --git a/app/src/main/java/org/pacien/tincapp/activities/common/SelfRefreshingLiveData.kt b/app/src/main/java/org/pacien/tincapp/activities/common/SelfRefreshingLiveData.kt
new file mode 100644
index 0000000..cb98736
--- /dev/null
+++ b/app/src/main/java/org/pacien/tincapp/activities/common/SelfRefreshingLiveData.kt
@@ -0,0 +1,42 @@
+/*
+ * Tinc App, an Android binding and user interface for the tinc mesh VPN daemon
+ * Copyright (C) 2017-2018 Pacien TRAN-GIRARD
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package org.pacien.tincapp.activities.common
+
+import android.arch.lifecycle.LiveData
+import java.util.concurrent.Executors
+import java.util.concurrent.ScheduledFuture
+import java.util.concurrent.TimeUnit
+
+/**
+ * @author pacien
+ */
+abstract class SelfRefreshingLiveData<T>(private val refreshInterval: Long, private val timeUnit: TimeUnit) : LiveData<T>() {
+  private val scheduledExecutor = Executors.newSingleThreadScheduledExecutor()
+  private lateinit var scheduledFuture: ScheduledFuture<*>
+
+  override fun onActive() {
+    scheduledFuture = scheduledExecutor.scheduleWithFixedDelay(this::onRefresh, 0, refreshInterval, timeUnit)
+  }
+
+  override fun onInactive() {
+    scheduledFuture.cancel(false)
+  }
+
+  abstract fun onRefresh()
+}
diff --git a/app/src/main/java/org/pacien/tincapp/activities/start/NetworkListLiveData.kt b/app/src/main/java/org/pacien/tincapp/activities/start/NetworkListLiveData.kt
index d0d39b8..aaab0e7 100644
--- a/app/src/main/java/org/pacien/tincapp/activities/start/NetworkListLiveData.kt
+++ b/app/src/main/java/org/pacien/tincapp/activities/start/NetworkListLiveData.kt
@@ -18,28 +18,17 @@
 
 package org.pacien.tincapp.activities.start
 
-import android.arch.lifecycle.LiveData
+import org.pacien.tincapp.activities.common.SelfRefreshingLiveData
 import org.pacien.tincapp.context.AppPaths
-import java.util.*
-import kotlin.concurrent.timer
+import java.util.concurrent.TimeUnit
 
 /**
  * @author pacien
  */
-class NetworkListLiveData : LiveData<List<String>>() {
-  private val updateInterval = 2 * 1000L // in milliseconds
+class NetworkListLiveData : SelfRefreshingLiveData<List<String>>(1, TimeUnit.SECONDS) {
   private val appPaths = AppPaths
-  private lateinit var updateTimer: Timer
 
-  override fun onActive() {
-    updateTimer = timer(period = updateInterval, action = { updateNetworkList() })
-  }
-
-  override fun onInactive() {
-    updateTimer.apply { cancel() }.apply { purge() }
-  }
-
-  private fun updateNetworkList() {
+  override fun onRefresh() {
     val networkList = appPaths.confDir().list()?.sorted() ?: emptyList()
     postValue(networkList)
   }
diff --git a/app/src/main/java/org/pacien/tincapp/activities/status/nodes/NodeListLiveData.kt b/app/src/main/java/org/pacien/tincapp/activities/status/nodes/NodeListLiveData.kt
index cdbdf0a..70ea54e 100644
--- a/app/src/main/java/org/pacien/tincapp/activities/status/nodes/NodeListLiveData.kt
+++ b/app/src/main/java/org/pacien/tincapp/activities/status/nodes/NodeListLiveData.kt
@@ -18,30 +18,21 @@
 
 package org.pacien.tincapp.activities.status.nodes
 
-import android.arch.lifecycle.LiveData
+import org.pacien.tincapp.activities.common.SelfRefreshingLiveData
 import org.pacien.tincapp.commands.Tinc
-import java.util.*
-import kotlin.concurrent.timer
+import java.util.concurrent.TimeUnit
 
 /**
  * @author pacien
  */
-class NodeListLiveData(private val netName: String) : LiveData<List<String>>() {
-  private val updateInterval = 2 * 1000L // in milliseconds
+class NodeListLiveData(private val netName: String) : SelfRefreshingLiveData<List<String>>(1, TimeUnit.SECONDS) {
   private val tincCtl = Tinc
-  private lateinit var updateTimer: Timer
 
-  override fun onActive() {
-    updateTimer = timer(period = updateInterval, action = { updateNodeList() })
-  }
-
-  override fun onInactive() {
-    updateTimer.apply { cancel() }.apply { purge() }
-  }
+  override fun onRefresh() {
+    val nodeList = tincCtl.dumpNodes(netName)
+      .thenApply { list -> list.map { it.substringBefore(' ') } }
+      .get()
 
-  private fun updateNodeList() {
-    tincCtl.dumpNodes(netName)
-      .thenApply { list -> list.map { it.substringBefore(' ')} }
-      .thenAccept(this::postValue)
+    postValue(nodeList)
   }
 }
diff --git a/app/src/main/java/org/pacien/tincapp/activities/viewlog/LogLiveData.kt b/app/src/main/java/org/pacien/tincapp/activities/viewlog/LogLiveData.kt
index f410a8c..9767e12 100644
--- a/app/src/main/java/org/pacien/tincapp/activities/viewlog/LogLiveData.kt
+++ b/app/src/main/java/org/pacien/tincapp/activities/viewlog/LogLiveData.kt
@@ -18,30 +18,37 @@
 
 package org.pacien.tincapp.activities.viewlog
 
-import android.arch.lifecycle.LiveData
+import org.pacien.tincapp.activities.common.SelfRefreshingLiveData
 import org.pacien.tincapp.commands.Executor
 import org.pacien.tincapp.commands.Tinc
 import java.util.*
-import kotlin.concurrent.timer
+import java.util.concurrent.TimeUnit
 
 /**
  * @author pacien
  */
-class LogLiveData(private val netName: String, private val logLevel: Int, private val logLineSize: Int) : LiveData<List<String>>() {
-  private val updateInterval = 250L // milliseconds
+class LogLiveData(private val netName: String, private val logLevel: Int, private val logLineSize: Int)
+  : SelfRefreshingLiveData<List<String>>(250, TimeUnit.MILLISECONDS) {
+
   private val executor = Executor
   private val log = LinkedList<String>()
-  private var loggerProcess: Process? = null
-  private var logUpdateTimer: Timer? = null
+  private lateinit var loggerProcess: Process
 
   override fun onActive() {
+    super.onActive()
     loggerProcess = startNewLogger()
-    logUpdateTimer = timer(period = updateInterval, action = { outputLog() })
   }
 
   override fun onInactive() {
-    loggerProcess?.destroy()
-    logUpdateTimer?.apply { cancel() }?.apply { purge() }
+    loggerProcess.destroy()
+    super.onInactive()
+  }
+
+  override fun onRefresh() {
+    synchronized(log) {
+      val logView = ArrayList(log)
+      postValue(logView)
+    }
   }
 
   private fun startNewLogger(): Process {
@@ -64,11 +71,4 @@ class LogLiveData(private val netName: String, private val logLevel: Int, privat
       log.addLast(line)