refactor update graph and prevent crash if view is no longer available.

app/src/main/java/info/nightscout/androidaps/plugins/general/overview/OverviewFragment.kt

@@ -37,11 +37,7 @@ import info.nightscout.androidaps.dialogs.InsulinDialog
 import info.nightscout.androidaps.dialogs.TreatmentDialog
 import info.nightscout.androidaps.dialogs.WizardDialog
 import info.nightscout.androidaps.events.*
-import info.nightscout.androidaps.interfaces.ActivePluginProvider
+import info.nightscout.androidaps.interfaces.*
-import info.nightscout.androidaps.interfaces.Constraint
-import info.nightscout.androidaps.interfaces.DatabaseHelperInterface
-import info.nightscout.androidaps.interfaces.PluginType
-import info.nightscout.androidaps.interfaces.ProfileFunction
 import info.nightscout.androidaps.logging.AAPSLogger
 import info.nightscout.androidaps.plugins.aps.loop.LoopPlugin
 import info.nightscout.androidaps.plugins.aps.loop.events.EventNewOpenLoopNotification
@@ -76,36 +72,16 @@ import io.reactivex.android.schedulers.AndroidSchedulers
 import io.reactivex.disposables.CompositeDisposable
 import io.reactivex.schedulers.Schedulers
 import kotlinx.android.synthetic.main.overview_buttons_layout.*
-import kotlinx.android.synthetic.main.overview_buttons_layout.overview_carbsbutton
-import kotlinx.android.synthetic.main.overview_buttons_layout.overview_insulinbutton
-import kotlinx.android.synthetic.main.overview_buttons_layout.overview_quickwizardbutton
-import kotlinx.android.synthetic.main.overview_buttons_layout.overview_treatmentbutton
-import kotlinx.android.synthetic.main.overview_buttons_layout.overview_wizardbutton
 import kotlinx.android.synthetic.main.overview_fragment.overview_notifications
 import kotlinx.android.synthetic.main.overview_fragment_nsclient.*
-import kotlinx.android.synthetic.main.overview_graphs_layout.overview_bggraph
+import kotlinx.android.synthetic.main.overview_graphs_layout.*
-import kotlinx.android.synthetic.main.overview_graphs_layout.overview_chartMenuButton
-import kotlinx.android.synthetic.main.overview_graphs_layout.overview_iobcalculationprogess
-import kotlinx.android.synthetic.main.overview_graphs_layout.overview_iobgraph
 import kotlinx.android.synthetic.main.overview_info_layout.*
-import kotlinx.android.synthetic.main.overview_info_layout.overview_arrow
-import kotlinx.android.synthetic.main.overview_info_layout.overview_basebasal
-import kotlinx.android.synthetic.main.overview_info_layout.overview_bg
-import kotlinx.android.synthetic.main.overview_info_layout.overview_cob
-import kotlinx.android.synthetic.main.overview_info_layout.overview_extendedbolus
-import kotlinx.android.synthetic.main.overview_info_layout.overview_iob
-import kotlinx.android.synthetic.main.overview_info_layout.overview_sensitivity
-import kotlinx.android.synthetic.main.overview_info_layout.overview_time
-import kotlinx.android.synthetic.main.overview_info_layout.overview_timeagoshort
 import kotlinx.android.synthetic.main.overview_loop_pumpstatus_layout.*
 import kotlinx.android.synthetic.main.overview_statuslights_layout.*
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import java.util.*
-import java.util.concurrent.Executors
-import java.util.concurrent.ScheduledFuture
-import java.util.concurrent.TimeUnit
 import javax.inject.Inject
 import kotlin.collections.ArrayList
 import kotlin.math.abs
@@ -155,9 +131,6 @@ class OverviewFragment : DaggerFragment(), View.OnClickListener, OnLongClickList
     private var loopHandler = Handler()
     private var refreshLoop: Runnable? = null
 
-    private val worker = Executors.newSingleThreadScheduledExecutor()
-    private var scheduledUpdate: ScheduledFuture<*>? = null
-
     private val secondaryGraphs = ArrayList<GraphView>()
     private val secondaryGraphsLabel = ArrayList<TextView>()
 
@@ -522,21 +495,19 @@ class OverviewFragment : DaggerFragment(), View.OnClickListener, OnLongClickList
         }
     }
 
+    var task: Runnable? = null
+
     private fun scheduleUpdateGUI(from: String) {
         class UpdateRunnable : Runnable {
 
             override fun run() {
-                activity?.runOnUiThread {
+                updateGUI(from)
-                    updateGUI(from)
+                task = null
-                    scheduledUpdate = null
-                }
             }
         }
-        // prepare task for execution in 500 milliseconds
+        view?.removeCallbacks(task)
-        // cancel waiting task to prevent multiple updates
+        task = UpdateRunnable()
-        scheduledUpdate?.cancel(false)
+        view?.postDelayed(task, 500)
-        val task: Runnable = UpdateRunnable()
-        scheduledUpdate = worker.schedule(task, 500, TimeUnit.MILLISECONDS)
     }
 
     @SuppressLint("SetTextI18n")
@@ -562,6 +533,14 @@ class OverviewFragment : DaggerFragment(), View.OnClickListener, OnLongClickList
         val units = profileFunction.getUnits()
         val lowLine = defaultValueHelper.determineLowLine()
         val highLine = defaultValueHelper.determineHighLine()
+        val lastRun = loopPlugin.lastRun
+        val predictionsAvailable = if (config.APS) lastRun?.request?.hasPredictions == true else config.NSCLIENT
+
+        try {
+            updateGraph(lastRun, predictionsAvailable, lowLine, highLine, pump, profile)
+        } catch (e: IllegalStateException) {
+            return // view no longer exists
+        }
 
         //Start with updating the BG as it is unaffected by loop.
         // **** BG value ****
@@ -664,8 +643,6 @@ class OverviewFragment : DaggerFragment(), View.OnClickListener, OnLongClickList
             overview_apsmode_text?.visibility = View.GONE
             overview_time_llayout?.visibility = View.VISIBLE
         }
-        val lastRun = loopPlugin.lastRun
-        val predictionsAvailable = if (config.APS) lastRun?.request?.hasPredictions == true else config.NSCLIENT
 
         // temp target
         val tempTarget = treatmentsPlugin.tempTargetFromHistory
@@ -803,8 +780,9 @@ class OverviewFragment : DaggerFragment(), View.OnClickListener, OnLongClickList
             iobCobCalculatorPlugin.getLastAutosensData("Overview")?.let { autosensData ->
                 String.format(Locale.ENGLISH, "%.0f%%", autosensData.autosensResult.ratio * 100)
             } ?: ""
+    }
 
-        // ****** GRAPH *******
+    private fun updateGraph(lastRun: LoopInterface.LastRun?, predictionsAvailable: Boolean, lowLine: Double, highLine: Double, pump: PumpInterface, profile: Profile) {
         viewLifecycleOwner.lifecycleScope.launch(Dispatchers.Main) {
             overview_bggraph ?: return@launch
             val graphData = GraphData(injector, overview_bggraph, iobCobCalculatorPlugin, treatmentsPlugin)