Fix and improve service switching (introduced colors)

- Every service now have its own colors
- Fix bug navigation button and backstack count
- Fix and themed properly the icons and colors of the main fragment tabs
- Re-organized the styles and colors (too much in one file)

app/src/main/java/org/schabi/newpipe/util/ServiceHelper.java

@@ -0,0 +1,67 @@
+package org.schabi.newpipe.util;
+
+import android.content.Context;
+import android.preference.PreferenceManager;
+import android.support.annotation.DrawableRes;
+
+import org.schabi.newpipe.BuildConfig;
+import org.schabi.newpipe.R;
+import org.schabi.newpipe.extractor.NewPipe;
+import org.schabi.newpipe.extractor.ServiceList;
+import org.schabi.newpipe.extractor.StreamingService;
+import org.schabi.newpipe.extractor.exceptions.ExtractionException;
+
+public class ServiceHelper {
+    private static final StreamingService DEFAULT_FALLBACK_SERVICE = ServiceList.YouTube.getService();
+
+    @DrawableRes
+    public static int getIcon(int serviceId) {
+        switch (serviceId) {
+            case 0:
+                return R.drawable.youtube;
+            case 1:
+                return R.drawable.soundcloud;
+            default:
+                return R.drawable.service;
+        }
+    }
+
+    public static int getSelectedServiceId(Context context) {
+        if (BuildConfig.BUILD_TYPE.equals("release")) return DEFAULT_FALLBACK_SERVICE.getServiceId();
+
+        final String serviceName = PreferenceManager.getDefaultSharedPreferences(context)
+                .getString(context.getString(R.string.current_service_key), context.getString(R.string.default_service_value));
+
+        int serviceId;
+        try {
+            serviceId = NewPipe.getService(serviceName).getServiceId();
+        } catch (ExtractionException e) {
+            serviceId = DEFAULT_FALLBACK_SERVICE.getServiceId();
+        }
+
+        return serviceId;
+    }
+
+    public static void setSelectedServiceId(Context context, int serviceId) {
+        String serviceName;
+        try {
+            serviceName = NewPipe.getService(serviceId).getServiceInfo().name;
+        } catch (ExtractionException e) {
+            serviceName = DEFAULT_FALLBACK_SERVICE.getServiceInfo().name;
+        }
+
+        setSelectedServicePreferences(context, serviceName);
+    }
+
+    public static void setSelectedServiceId(Context context, String serviceName) {
+        int serviceId = NewPipe.getIdOfService(serviceName);
+        if (serviceId == -1) serviceName = DEFAULT_FALLBACK_SERVICE.getServiceInfo().name;
+
+        setSelectedServicePreferences(context, serviceName);
+    }
+
+    private static void setSelectedServicePreferences(Context context, String serviceName) {
+        PreferenceManager.getDefaultSharedPreferences(context).edit().
+                putString(context.getString(R.string.current_service_key), serviceName).apply();
+    }
+}

app/src/main/java/org/schabi/newpipe/util/ServiceIconMapper.java

@@ -1,35 +0,0 @@
-package org.schabi.newpipe.util;
-
-import org.schabi.newpipe.R;
-import org.schabi.newpipe.extractor.NewPipe;
-
-/**
- * Created by Chrsitian Schabesberger on 09.10.17.
- * ServiceIconMapper.java is part of NewPipe.
- *
- * NewPipe 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.
- *
- * NewPipe 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 NewPipe.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-public class ServiceIconMapper {
-    public static int getIconResource(int service_id) {
-        switch(service_id) {
-            case 0:
-                return R.drawable.youtube;
-            case 1:
-                return R.drawable.soud_cloud;
-            default:
-                return R.drawable.service;
-        }
-    }
-}

app/src/main/java/org/schabi/newpipe/util/ThemeHelper.java

@@ -7,16 +7,32 @@ import android.support.annotation.AttrRes;
 import android.support.annotation.StyleRes;
 
 import org.schabi.newpipe.R;
+import org.schabi.newpipe.extractor.NewPipe;
+import org.schabi.newpipe.extractor.StreamingService;
+import org.schabi.newpipe.extractor.exceptions.ExtractionException;
 
 public class ThemeHelper {
 
     /**
      * Apply the selected theme (on NewPipe settings) in the context
+     * with the default style (see {@link #setTheme(Context, int)}).
      *
      * @param context context that the theme will be applied
      */
     public static void setTheme(Context context) {
-        context.setTheme(getSelectedThemeStyle(context));
+        setTheme(context, -1);
+    }
+
+    /**
+     * Apply the selected theme (on NewPipe settings) in the context,
+     * themed according with the styles defined for the service .
+     *
+     * @param context   context that the theme will be applied
+     * @param serviceId the theme will be styled to the service with this id,
+     *                  pass -1 to get the default style
+     */
+    public static void setTheme(Context context, int serviceId) {
+        context.setTheme(getThemeForService(context, serviceId));
     }
 
     /**
@@ -29,18 +45,42 @@ public class ThemeHelper {
     }
 
     @StyleRes
-    public static int getSelectedThemeStyle(Context context) {
+    public static int getThemeForService(Context context, int serviceId) {
         String lightTheme = context.getResources().getString(R.string.light_theme_key);
         String darkTheme = context.getResources().getString(R.string.dark_theme_key);
         String blackTheme = context.getResources().getString(R.string.black_theme_key);
 
         String selectedTheme = getSelectedTheme(context);
 
-        if (selectedTheme.equals(lightTheme)) return R.style.LightTheme;
-        else if (selectedTheme.equals(blackTheme)) return R.style.BlackTheme;
-        else if (selectedTheme.equals(darkTheme)) return R.style.DarkTheme;
-            // Fallback
-        else return R.style.DarkTheme;
+        int defaultTheme = R.style.DarkTheme;
+        if (selectedTheme.equals(lightTheme)) defaultTheme = R.style.LightTheme;
+        else if (selectedTheme.equals(blackTheme)) defaultTheme = R.style.BlackTheme;
+        else if (selectedTheme.equals(darkTheme)) defaultTheme = R.style.DarkTheme;
+
+        if (serviceId <= -1) {
+            return defaultTheme;
+        }
+
+        final StreamingService service;
+        try {
+            service = NewPipe.getService(serviceId);
+        } catch (ExtractionException ignored) {
+            return defaultTheme;
+        }
+
+        String themeName = "DarkTheme";
+        if (selectedTheme.equals(lightTheme)) themeName = "LightTheme";
+        else if (selectedTheme.equals(blackTheme)) themeName = "BlackTheme";
+        else if (selectedTheme.equals(darkTheme)) themeName = "DarkTheme";
+
+        themeName += "." + service.getServiceInfo().name;
+        int resourceId = context.getResources().getIdentifier(themeName, "style", context.getPackageName());
+
+        if (resourceId > 0) {
+            return resourceId;
+        }
+
+        return defaultTheme;
     }
 
     public static String getSelectedTheme(Context context) {