add button to show current sun position

app/src/main/java/org/woheller69/weather/activities/ForecastCityActivity.java

@@ -5,6 +5,7 @@ import android.content.Intent;
 import android.content.SharedPreferences;
 import android.os.Bundle;
 
+import androidx.appcompat.app.AlertDialog;
 import androidx.preference.PreferenceManager;
 import com.google.android.material.tabs.TabLayout;
 import com.google.android.material.tabs.TabLayoutMediator;
@@ -19,17 +20,24 @@ import android.view.animation.Animation;
 import android.view.animation.LinearInterpolator;
 import android.view.animation.RotateAnimation;
 import android.widget.TextView;
+import net.e175.klaus.solarpositioning.AzimuthZenithAngle;
+import net.e175.klaus.solarpositioning.DeltaT;
+import net.e175.klaus.solarpositioning.Grena3;
 
 import org.woheller69.weather.R;
 import org.woheller69.weather.database.GeneralData;
 import org.woheller69.weather.database.HourlyForecast;
 import org.woheller69.weather.database.SQLiteHelper;
 import org.woheller69.weather.database.WeekForecast;
+import org.woheller69.weather.ui.Help.StringFormatUtils;
 import org.woheller69.weather.ui.updater.IUpdateableCityUI;
 import org.woheller69.weather.ui.updater.ViewUpdater;
 import org.woheller69.weather.ui.viewPager.WeatherPagerAdapter;
 
 import java.lang.reflect.Field;
+import java.time.Instant;
+import java.time.ZoneId;
+import java.time.ZonedDateTime;
 import java.util.List;
 
 public class ForecastCityActivity extends NavigationActivity implements IUpdateableCityUI {
@@ -179,6 +187,26 @@ public class ForecastCityActivity extends NavigationActivity implements IUpdatea
                 WeatherPagerAdapter.refreshSingleData(getApplicationContext(),true, pagerAdapter.getCityIDForPos(viewPager2.getCurrentItem()));
                 ForecastCityActivity.startRefreshAnimation();
             }
+        } else if (id==R.id.menu_sun_position){
+            Long time = System.currentTimeMillis()/1000;
+            Instant i = Instant.ofEpochSecond(time); //currentTimeMillis is in GMT
+            ZonedDateTime dateTime = ZonedDateTime.ofInstant(i, ZoneId.of("GMT"));
+            AzimuthZenithAngle position = Grena3.calculateSolarPosition(
+                    dateTime,
+                    db.getCityToWatch(cityId).getLatitude(),
+                    db.getCityToWatch(cityId).getLongitude(),
+                    DeltaT.estimate(dateTime.toLocalDate())); // delta T (s)
+
+            String solarAzimuth = StringFormatUtils.formatDecimal((float) position.getAzimuth(),"");
+            String solarElevation = StringFormatUtils.formatDecimal((float) (90 - position.getZenithAngle()),"");
+
+            AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(this);
+            alertDialogBuilder.setTitle(R.string.action_sun_position);
+
+            alertDialogBuilder.setMessage(getString(R.string.edit_location_hint_azimuth)+": "+solarAzimuth + " \n" + getString(R.string.action_sun_elevation) + ": " + solarElevation);
+            alertDialogBuilder.setPositiveButton(getString(android.R.string.ok), (dialog, which) -> { });
+            AlertDialog alertDialog = alertDialogBuilder.create();
+            alertDialog.show();
         }
 
         return super.onOptionsItemSelected(item);

app/src/main/res/drawable/ic_solar_power_24px.xml

@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="960"
+    android:viewportHeight="960">
+  <path
+      android:fillColor="#FF000000"
+      android:pathData="m80,880 l80,-400h640l80,400L80,880ZM120,160v-80h120v80L120,160ZM178,800h262v-80L194,720l-16,80ZM245,373 L188,317 273,232 330,288 245,373ZM210,640h230v-80L226,560l-16,80ZM480,280q-83,0 -141.5,-58.5T280,80h80q0,50 35,85t85,35q50,0 85,-35t35,-85h80q0,83 -58.5,141.5T480,280ZM480,80ZM440,440L440,320h80v120h-80ZM520,800h262l-16,-80L520,720v80ZM520,640h230l-16,-80L520,560v80ZM715,373 L631,288 687,232 772,316 715,373ZM720,160v-80h120v80L720,160Z"/>
+</vector>

app/src/main/res/drawable/ic_wb_sunny_24px.xml

@@ -4,6 +4,6 @@
     android:viewportWidth="24"
     android:viewportHeight="24">
   <path
-      android:fillColor="#FF000000"
+      android:fillColor="#FFFFFFFF"
       android:pathData="M6.76,4.84l-1.8,-1.79 -1.41,1.41 1.79,1.79 1.42,-1.41zM4,10.5L1,10.5v2h3v-2zM13,0.55h-2L11,3.5h2L13,0.55zM20.45,4.46l-1.41,-1.41 -1.79,1.79 1.41,1.41 1.79,-1.79zM17.24,18.16l1.79,1.8 1.41,-1.41 -1.8,-1.79 -1.4,1.4zM20,10.5v2h3v-2h-3zM12,5.5c-3.31,0 -6,2.69 -6,6s2.69,6 6,6 6,-2.69 6,-6 -2.69,-6 -6,-6zM11,22.45h2L13,19.5h-2v2.95zM3.55,18.54l1.41,1.41 1.79,-1.8 -1.41,-1.41 -1.79,1.8z"/>
 </vector>

app/src/main/res/menu/activity_forecast_city.xml

@@ -2,14 +2,12 @@
 <menu xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto">
     <item
-        android:id="@+id/menu_update_location"
+        android:id="@+id/menu_sun_position"
         android:orderInCategory="80"
-        android:visible="false"
+        android:visible="true"
-        android:icon="@drawable/ic_location_on_white_24dp"
+        android:icon="@drawable/ic_wb_sunny_24px"
-        app:actionViewClass="android.widget.ImageButton"
         app:showAsAction="always"
-        style="@android:style/Widget.ActionButton"
+        android:title="@string/action_sun_position" />
-        android:title="@string/action_position" />
     <item
         android:id="@+id/menu_refresh"
         android:orderInCategory="90"

app/src/main/res/menu/activity_main_drawer.xml

@@ -6,7 +6,7 @@
         android:checkableBehavior="all">
         <item
             android:id="@+id/nav_weather"
-            android:icon="@drawable/ic_wb_sunny_24px"
+            android:icon="@drawable/ic_solar_power_24px"
             android:title="@string/activity_weather" />
         <item
             android:id="@+id/nav_manage"

app/src/main/res/values-de/strings.xml

@@ -131,5 +131,7 @@
     <string name="edit_location_shading_opacity_heading">Abschattung unterhalb dieser Elevation [%]</string>
     <string name="edit_location_shading_heading">Abschattung</string>
     <string name="activity_help">Anleitung</string>
+    <string name="action_sun_position">Sonnenposition</string>
+    <string name="action_sun_elevation">Elevation [°]</string>
 
 </resources>

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

@@ -133,4 +133,6 @@
     <string name="edit_location_shading_opacity_heading">Shading below this elevation [%]</string>
     <string name="edit_location_shading_heading">Shading</string>
     <string name="activity_help">Instructions</string>
+    <string name="action_sun_position">Sun position</string>
+    <string name="action_sun_elevation">Elevation [°]</string>
 </resources>