feat: mejoras de interfaz v10.1.4 - botón refresh visible, límite de scroll y barra indicadora

Cambios implementados:

1. Botón de Actualización Más Visible (para control remoto)
   - Nuevo archivo: btn_refresh_selector.xml con estados de foco
   - Color ámbar brillante (#FFC107) cuando está enfocado
   - Borde grueso (4dp) para mejor visibilidad

2. Prevención de Navegación Entre Secciones
   - Modificado: MainActivity.java showEvents()
   - Agregado OnScrollListener que detiene scroll al final de eventos
   - Previene paso accidental a sección de canales

3. Barra de Indicador de Scroll
   - Nuevo archivo: scrollbar_vertical.xml (drawable)
   - Modificado: activity_main.xml con atributos de scrollbar
   - Barra visual derecha como indicador de posición

Archivos modificados:
- app/src/main/java/com/streamplayer/MainActivity.java
- app/src/main/res/layout/activity_main.xml
- app/src/main/res/values/colors.xml

Archivos nuevos:
- app/src/main/res/drawable/btn_refresh_selector.xml
- app/src/main/res/drawable/scrollbar_vertical.xml

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/src/main/java/com/streamplayer/MainActivity.java

@@ -14,6 +14,7 @@ import android.widget.TextView;
 import android.widget.Toast;
 import android.text.TextUtils;
 
+import androidx.annotation.NonNull;
 import androidx.appcompat.app.AppCompatActivity;
 import androidx.recyclerview.widget.GridLayoutManager;
 import androidx.recyclerview.widget.LinearLayoutManager;
@@ -169,6 +170,8 @@ public class MainActivity extends AppCompatActivity {
         refreshButton.setVisibility(View.GONE);
         contentList.setLayoutManager(channelLayoutManager);
         contentList.setAdapter(channelAdapter);
+        // Clear any scroll listeners from Events section
+        contentList.clearOnScrollListeners();
         loadingIndicator.setVisibility(View.GONE);
         channelAdapter.submitList(section.channels);
         if (section.channels.isEmpty()) {
@@ -185,6 +188,26 @@ public class MainActivity extends AppCompatActivity {
         refreshButton.setVisibility(View.VISIBLE);
         contentList.setLayoutManager(eventLayoutManager);
         contentList.setAdapter(eventAdapter);
+        // Add scroll listener to prevent scrolling from Events to Channels section
+        contentList.clearOnScrollListeners();
+        contentList.addOnScrollListener(new RecyclerView.OnScrollListener() {
+            @Override
+            public void onScrolled(@NonNull RecyclerView recyclerView, int dx, int dy) {
+                super.onScrolled(recyclerView, dx, dy);
+                // Only prevent downward scroll when at the last item
+                if (dy > 0) {  // Scrolling down
+                    int visibleItemCount = eventLayoutManager.getChildCount();
+                    int totalItemCount = eventLayoutManager.getItemCount();
+                    int firstVisibleItemPosition = eventLayoutManager.findFirstVisibleItemPosition();
+
+                    // Check if we're at the last item
+                    if (firstVisibleItemPosition + visibleItemCount >= totalItemCount) {
+                        // Prevent further scrolling by stopping the scroll
+                        recyclerView.stopScroll();
+                    }
+                }
+            }
+        });
         if (cachedEvents.isEmpty()) {
             loadEvents(false);
         } else {

app/src/main/res/drawable/btn_refresh_selector.xml

@@ -0,0 +1,45 @@
+<?xml version="1.0" encoding="utf-8"?>
+<selector xmlns:android="http://schemas.android.com/apk/res/android">
+    <!-- Focused state - bright amber with thick border -->
+    <item android:state_focused="true">
+        <shape android:shape="rectangle">
+            <solid android:color="@color/refresh_button_focused" />
+            <corners android:radius="8dp" />
+            <stroke
+                android:width="4dp"
+                android:color="@color/refresh_button_focused_border" />
+            <padding
+                android:left="12dp"
+                android:top="8dp"
+                android:right="12dp"
+                android:bottom="8dp" />
+        </shape>
+    </item>
+
+    <!-- Pressed state -->
+    <item android:state_pressed="true">
+        <shape android:shape="rectangle">
+            <solid android:color="@color/refresh_button_pressed" />
+            <corners android:radius="8dp" />
+            <stroke
+                android:width="2dp"
+                android:color="@color/refresh_button_border" />
+        </shape>
+    </item>
+
+    <!-- Default state - darker background with subtle border -->
+    <item>
+        <shape android:shape="rectangle">
+            <solid android:color="@color/refresh_button_default" />
+            <corners android:radius="8dp" />
+            <stroke
+                android:width="2dp"
+                android:color="@color/refresh_button_border" />
+            <padding
+                android:left="12dp"
+                android:top="8dp"
+                android:right="12dp"
+                android:bottom="8dp" />
+        </shape>
+    </item>
+</selector>

app/src/main/res/drawable/scrollbar_vertical.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="rectangle">
+    <solid android:color="#4DFFFFFF" />
+    <corners android:radius="2dp" />
+</shape>

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

@@ -97,7 +97,10 @@
                 android:textSize="12sp"
                 android:visibility="gone"
                 android:focusable="true"
-                android:focusableInTouchMode="true" />
+                android:focusableInTouchMode="true"
+                android:background="@drawable/btn_refresh_selector"
+                android:textColor="@color/white"
+                android:elevation="2dp" />
 
         </LinearLayout>
 
@@ -125,6 +128,9 @@
             android:layout_marginTop="16dp"
             android:layout_weight="1"
             android:overScrollMode="never"
+            android:scrollbars="vertical"
+            android:scrollbarStyle="outsideOverlay"
+            android:scrollbarThumbVertical="@drawable/scrollbar_vertical"
             android:nextFocusLeft="@id/section_list"
             tools:listitem="@layout/item_channel" />
     </LinearLayout>

app/src/main/res/values/colors.xml

@@ -3,4 +3,11 @@
     <color name="black">#FF000000</color>
     <color name="white">#FFFFFFFF</color>
     <color name="text_secondary">#B3FFFFFF</color>
+
+    <!-- Refresh button colors -->
+    <color name="refresh_button_default">#2A2A2A</color>
+    <color name="refresh_button_border">#4A4A4A</color>
+    <color name="refresh_button_focused">#FFC107</color>
+    <color name="refresh_button_focused_border">#FFD54F</color>
+    <color name="refresh_button_pressed">#FF9800</color>
 </resources>