ADFA-3130 | Fix memory usage chart crash

app/src/main/java/com/itsaky/androidide/ui/SafeLineChart.kt

@@ -0,0 +1,67 @@
+/*
+ *  This file is part of AndroidIDE.
+ *
+ *  AndroidIDE 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.
+ *
+ *  AndroidIDE 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 AndroidIDE.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.itsaky.androidide.ui
+
+import android.content.Context
+import android.graphics.Canvas
+import android.util.AttributeSet
+import com.github.mikephil.charting.charts.LineChart
+import org.slf4j.LoggerFactory
+
+/**
+ * A [LineChart] that guards its [onDraw] against the MPAndroidChart axis-rendering race.
+ *
+ * MPAndroidChart is not thread-safe: [com.github.mikephil.charting.renderer.AxisRenderer.computeAxisValues]
+ * writes `mEntryCount` and reallocates the `mEntries` array in two separate statements. When the view is
+ * drawn from more than one thread at once, a reader can observe the new `mEntryCount` while `mEntries` is
+ * still the old (shorter) array, throwing an [IndexOutOfBoundsException] from the label renderer.
+ *
+ * This happens in AndroidIDE because Sentry Session Replay records the screen by drawing the view
+ * hierarchy on a background thread, which races the main-thread updates of the memory-usage chart. The
+ * chart is a non-critical diagnostic view, so dropping the occasional frame is preferable to crashing the
+ * whole IDE. The next `invalidate()` recovers cleanly.
+ *
+ */
+class SafeLineChart : LineChart {
+
+  constructor(context: Context) : super(context)
+  constructor(context: Context, attrs: AttributeSet?) : super(context, attrs)
+  constructor(
+    context: Context,
+    attrs: AttributeSet?,
+    defStyleAttr: Int,
+  ) : super(context, attrs, defStyleAttr)
+
+  companion object {
+    private val log = LoggerFactory.getLogger(SafeLineChart::class.java)
+  }
+
+  private var skippedFrames = 0L
+
+  override fun onDraw(canvas: Canvas) {
+    try {
+      super.onDraw(canvas)
+    } catch (e: IndexOutOfBoundsException) {
+      // Transient race in MPAndroidChart's axis renderer (see class doc). Skip this frame.
+      // Only log occasionally to avoid flooding logcat, since onDraw runs every frame.
+      if (skippedFrames++ % 60L == 0L) {
+        log.warn("Skipped {} chart frame(s) due to a transient axis-rendering race", skippedFrames, e)
+      }
+    }
+  }
+}

app/src/main/res/layout/layout_mem_usage.xml

@@ -21,7 +21,7 @@
   android:layout_height="@dimen/editor_mem_usage_view_height">
 
   <!--  Need to wrap this in a layout so that we can apply margins at runtime-->
-  <com.github.mikephil.charting.charts.LineChart
+  <com.itsaky.androidide.ui.SafeLineChart
     android:id="@+id/chart"
     android:layout_width="0dp"
     android:layout_height="0dp"