Fix Android monitor scroll stability

android/TradeBotMonitor/app/build.gradle.kts

@@ -10,7 +10,7 @@ android {
         applicationId = "xyz.kusoft.tradebotmonitor"
         minSdk = 26
         targetSdk = 36
-        versionCode = 1
-        versionName = "0.1.0"
+        versionCode = 2
+        versionName = "0.1.1"
     }
 }

android/TradeBotMonitor/app/src/main/java/xyz/kusoft/tradebotmonitor/MainActivity.kt

@@ -39,6 +39,7 @@ class MainActivity : Activity() {
     private var lastError: String = ""
     private var activeTab: String = "markets"
     private var palette: AppPalette = AppPalette.dark()
+    private val scrollPositions = mutableMapOf<String, Int>()
 
     private val refreshRunnable = object : Runnable {
         override fun run() {
@@ -127,9 +128,12 @@ class MainActivity : Activity() {
         ).forEach { (id, title) ->
             tabBar.addView(
                 button(title, selected = activeTab == id) {
-                    activeTab = id
-                    renderTabs()
-                    render()
+                    if (activeTab != id) {
+                        saveCurrentScroll()
+                        activeTab = id
+                        renderTabs()
+                        render(saveScroll = false)
+                    }
                 },
                 LinearLayout.LayoutParams(0, dp(38), 1f).apply { setMargins(dp(3), 0, dp(3), 0) },
             )
@@ -150,7 +154,11 @@ class MainActivity : Activity() {
         styleLabel(statusView, if (data.ok && data.running) "ok" else "warn")
     }
 
-    private fun render() {
+    private fun render(saveScroll: Boolean = true) {
+        val tabForRender = activeTab
+        if (saveScroll) {
+            saveCurrentScroll(tabForRender)
+        }
         contentHost.removeAllViews()
         val view = when (activeTab) {
             "overview" -> overviewScreen()
@@ -159,6 +167,23 @@ class MainActivity : Activity() {
             else -> marketsScreen()
         }
         contentHost.addView(view)
+        restoreScroll(view, tabForRender)
+    }
+
+    private fun saveCurrentScroll(tabId: String = activeTab) {
+        val current = contentHost.getChildAt(0)
+        if (current is ScrollView) {
+            scrollPositions[tabId] = current.scrollY
+        }
+    }
+
+    private fun restoreScroll(view: View, tabId: String) {
+        if (view !is ScrollView) return
+        val savedY = scrollPositions[tabId] ?: 0
+        view.post {
+            val maxY = (view.getChildAt(0)?.height ?: 0) - view.height
+            view.scrollTo(0, savedY.coerceIn(0, maxOf(0, maxY)))
+        }
     }
 
     private fun overviewScreen(): View {
@@ -610,7 +635,8 @@ class MainActivity : Activity() {
             background = boxDrawable(if (selected) palette.blue else palette.panelAlt, if (selected) palette.blue else palette.line, 5)
             setOnClickListener { onClick() }
             isClickable = true
-            isFocusable = true
+            isFocusable = false
+            isFocusableInTouchMode = false
         }
 
     private fun label(title: String, kind: String): TextView =