added preference first day of week, need to implement in DateUtils

uhabits-android/src/main/java/org/isoron/uhabits/activities/common/views/HistoryChart.java

@@ -29,6 +29,7 @@ import android.view.*;
 import org.isoron.androidbase.utils.*;
 import org.isoron.uhabits.*;
 import org.isoron.uhabits.core.models.*;
+import org.isoron.uhabits.core.preferences.Preferences;
 import org.isoron.uhabits.core.utils.*;
 import org.isoron.uhabits.utils.*;
 
@@ -96,6 +97,8 @@ public class HistoryChart extends ScrollableChart
     @NonNull
     private Controller controller;
 
+    private int weekFirstDay;
+
     public HistoryChart(Context context)
     {
         super(context);
@@ -392,6 +395,14 @@ public class HistoryChart extends ScrollableChart
         initPaints();
         initDateFormats();
         initRects();
+        initWeekFirstDay();
+
+    }
+
+    private void initWeekFirstDay() {
+        HabitsApplication app = (HabitsApplication) getContext().getApplicationContext();
+        Preferences prefs = app.getComponent().getPreferences();
+        weekFirstDay = prefs.getWeekFirstDay();
     }
 
     private void initColors()
@@ -458,8 +469,10 @@ public class HistoryChart extends ScrollableChart
 
     private void updateDate()
     {
+
+
         baseDate = DateUtils.getStartOfTodayCalendar();
-        baseDate.setFirstDayOfWeek(Calendar.SATURDAY);
+        baseDate.setFirstDayOfWeek(weekFirstDay);
         baseDate.add(Calendar.DAY_OF_YEAR, -(getDataOffset() - 1) * 7);
 
         nDays = (nColumns - 1) * 7;

uhabits-android/src/main/res/values/constants.xml

@@ -47,6 +47,26 @@
         <item>1440</item>
     </string-array>
 
+    <string-array name="days_names">
+        <item>Sunday</item>
+        <item>Monday</item>
+        <item>Tuesday</item>
+        <item>Wednesday</item>
+        <item>Thursday</item>
+        <item>Friday</item>
+        <item>Saturday</item>
+    </string-array>
+
+    <string-array name="days_values" translatable="false">
+        <item>1</item>
+        <item>2</item>
+        <item>3</item>
+        <item>4</item>
+        <item>5</item>
+        <item>6</item>
+        <item>7</item>
+    </string-array>
+
     <string-array name="frequencyQuickSelect" translatable="false">
         <item>@string/every_day</item>
         <item>@string/every_week</item>
@@ -94,5 +114,6 @@
     </string-array>
 
     <string name="snooze_interval_default" translatable="false">15</string>
+    <string name="week_start_default" translatable="false">7</string>
     <string name="default_count" translatable="false">100</string>
 </resources>

uhabits-android/src/main/res/values/strings.xml

@@ -86,6 +86,7 @@
     <string name="pref_toggle_title">Toggle with short press</string>
     <string name="pref_toggle_description">Put checkmarks with a single tap instead of press-and-hold. More convenient, but might cause accidental toggles.</string>
     <string name="pref_snooze_interval_title">Snooze interval on reminders</string>
+    <string name="pref_week_start_title">First day of week</string>
     <string name="pref_rate_this_app">Rate this app on Google Play</string>
     <string name="pref_send_feedback">Send feedback to developer</string>
     <string name="pref_view_source_code">View source code at GitHub</string>
@@ -95,6 +96,7 @@
     <string name="name">Name</string>
     <string name="settings">Settings</string>
     <string name="snooze_interval">Snooze interval</string>
+    <string name="week_start">First day of week</string>
 
     <string name="hint_title">Did you know?</string>
     <string name="hint_drag">To rearrange the entries, press-and-hold on the name of the habit, then drag it to the correct place.</string>

uhabits-android/src/main/res/xml/preferences.xml

@@ -100,6 +100,20 @@
 
     </PreferenceCategory>
 
+    <PreferenceCategory
+        android:title="Custom Settings">
+
+        <ListPreference
+            android:defaultValue="@string/week_start_default"
+            android:dialogTitle="@string/week_start"
+            android:entries="@array/days_names"
+            android:entryValues="@array/days_values"
+            android:key="pref_week_start"
+            android:summary="%s"
+            android:title="@string/pref_week_start_title"/>
+
+    </PreferenceCategory>
+
     <PreferenceCategory
         android:key="pref_key_debug"
         android:title="@string/troubleshooting">

uhabits-core/src/main/java/org/isoron/uhabits/core/preferences/Preferences.java

@@ -145,6 +145,11 @@ public class Preferences
         return Long.parseLong(storage.getString("pref_snooze_interval", "15"));
     }
 
+    public int getWeekFirstDay()
+    {
+        return Integer.parseInt(storage.getString("pref_week_start", "7"));
+    }
+
     public String getSyncAddress()
     {
         return storage.getString("pref_sync_address", DEFAULT_SYNC_SERVER);