fix: compilation errors — val reassign + missing import

android/app/src/main/java/com/senstools/presentation/ui/charts/AccelChartManager.kt

@@ -18,26 +18,20 @@ class AccelChartManager(private val chart: LineChart) {
     private val yEntries = mutableListOf<Entry>()
     private val zEntries = mutableListOf<Entry>()
 
-    private val xDataSet: LineDataSet
-    private val yDataSet: LineDataSet
-    private val zDataSet: LineDataSet
+    private val xDataSet = createDataSet("X", Color.RED)
+    private val yDataSet = createDataSet("Y", Color.GREEN)
+    private val zDataSet = createDataSet("Z", Color.BLUE)
 
     private var index = 0
 
     init {
         try {
             setupChart()
-            xDataSet = createDataSet("X", Color.RED)
-            yDataSet = createDataSet("Y", Color.GREEN)
-            zDataSet = createDataSet("Z", Color.BLUE)
-
+        } catch (_: Exception) { }
+        try {
             val lineData = LineData(xDataSet, yDataSet, zDataSet)
             chart.data = lineData
-        } catch (_: Exception) {
-            xDataSet = createDataSet("X", Color.RED)
-            yDataSet = createDataSet("Y", Color.GREEN)
-            zDataSet = createDataSet("Z", Color.BLUE)
-        }
+        } catch (_: Exception) { }
     }
 
 

android/app/src/main/java/com/senstools/presentation/ui/charts/GyroChartManager.kt

@@ -18,26 +18,20 @@ class GyroChartManager(private val chart: LineChart) {
     private val yEntries = mutableListOf<Entry>()
     private val zEntries = mutableListOf<Entry>()
 
-    private val xDataSet: LineDataSet
-    private val yDataSet: LineDataSet
-    private val zDataSet: LineDataSet
+    private val xDataSet = createDataSet("X", Color.RED)
+    private val yDataSet = createDataSet("Y", Color.GREEN)
+    private val zDataSet = createDataSet("Z", Color.BLUE)
 
     private var index = 0
 
     init {
         try {
             setupChart()
-            xDataSet = createDataSet("X", Color.RED)
-            yDataSet = createDataSet("Y", Color.GREEN)
-            zDataSet = createDataSet("Z", Color.BLUE)
-
+        } catch (_: Exception) { }
+        try {
             val lineData = LineData(xDataSet, yDataSet, zDataSet)
             chart.data = lineData
-        } catch (_: Exception) {
-            xDataSet = createDataSet("X", Color.RED)
-            yDataSet = createDataSet("Y", Color.GREEN)
-            zDataSet = createDataSet("Z", Color.BLUE)
-        }
+        } catch (_: Exception) { }
     }
 
     private fun setupChart() {

android/app/src/main/java/com/senstools/presentation/ui/charts/MagnetometerBarManager.kt

@@ -16,28 +16,23 @@ class MagnetometerBarManager(private val chart: BarChart) {
     private val colors = listOf(Color.RED, Color.GREEN, Color.BLUE)
     private val labels = listOf("X", "Y", "Z")
 
-    private val dataSet: BarDataSet
+    private val dataSet = BarDataSet(mutableListOf(), "Magnetometer (µT)").apply {
+        setColors(colors)
+        setDrawValues(true)
+        valueTextColor = Color.WHITE
+        valueTextSize = 12f
+    }
 
     init {
         try {
             setupChart()
-            dataSet = BarDataSet(mutableListOf(), "Magnetometer (µT)").apply {
-                setColors(colors)
-                setDrawValues(true)
-                valueTextColor = Color.WHITE
-                valueTextSize = 12f
-            }
-
+        } catch (_: Exception) { }
+        try {
             val barData = BarData(dataSet).apply {
                 barWidth = 0.6f
             }
             chart.data = barData
-        } catch (_: Exception) {
-            // Chart init after view detach — will be recreated on next view creation
-            dataSet = BarDataSet(mutableListOf(), "").apply {
-                setColors(colors)
-            }
-        }
+        } catch (_: Exception) { }
     }
 
     private fun setupChart() {

android/app/src/main/java/com/senstools/presentation/ui/dashboard/DashboardFragment.kt

@@ -18,6 +18,7 @@ import androidx.lifecycle.repeatOnLifecycle
 import com.senstools.data.datasource.DataCollectionService
 import com.senstools.databinding.FragmentDashboardBinding
 import com.senstools.domain.ekf.EKFAttitude
+import com.senstools.domain.model.AttitudeData
 import com.senstools.domain.repository.DataRepository
 import com.senstools.presentation.ui.charts.AccelChartManager
 import com.senstools.presentation.ui.charts.GyroChartManager
@@ -155,7 +156,8 @@ class DashboardFragment : Fragment() {
 
                         // Guard against stale timestamps causing EKF divergence
                         val now = System.currentTimeMillis()
-                        if (sensor.timestamp > 0L && kotlin.math.abs(sensor.timestamp - now) > 10000L) {
+                        val tsDiff = if (sensor.timestamp > now) sensor.timestamp - now else now - sensor.timestamp
+                        if (sensor.timestamp > 0L && tsDiff > 10000L) {
                             // Timestamp too far in the future or past, reset EKF
                             ekfAttitude.reset()
                             ekfInitialized = false