fix(android): min/max dates not always correct when timezoneOffsetInMinutes is set

.maestro/timezone-offset-in-minutes.yml

@@ -3,8 +3,9 @@ appId: com.rn069
 - runFlow:
     file: utils/set-timezone.yml
     env:
-      TIMEZONE: Sweden
+      REGION: Sweden
       GMT: GMT+01:00
+      STATE: ''
 
 - runFlow: utils/launch.yml
 
@@ -53,8 +54,9 @@ appId: com.rn069
 - runFlow:
     file: utils/set-timezone.yml
     env:
-      TIMEZONE: Sweden
+      REGION: Sweden
       GMT: GMT+02:00
+      STATE: ''
 
 - runFlow: utils/launch.yml
 
@@ -118,3 +120,24 @@ appId: com.rn069
 - assertVisible: 'Thu Jun 1101 AM '
 
 - runFlow: utils/reset.yml
+
+# test: timezoneOffsetInMinutes combined with maximumDate/minimumDate in another timezone than current device.
+# Bug was reported here: https://github.com/henninghall/react-native-date-picker/issues/613
+- runFlow:
+    file: utils/set-timezone.yml
+    env:
+      REGION: 'United states'
+      STATE: Phoenix
+      GMT: GMT-07:00
+- runFlow: utils/launch.yml
+- runFlow:
+    file: utils/change-prop.yml
+    env:
+      PROP: timeZoneOffsetInMinutes
+      VALUE: 180
+- repeat:
+    times: 5
+    commands:
+      - runFlow: utils/swipe-wheel-1.yml
+- runFlow: utils/swipe-wheel-4.yml
+- assertVisible: 'Thu Jan 61000 AM '

.maestro/utils/select-region.yml

@@ -1,4 +1,14 @@
 appId: com.android.settings
 ---
 - tapOn: Region
-- inputText: ${TIMEZONE}
+- inputText: ${REGION}
+- tapOn:
+    text: ${REGION}
+    index: 1
+
+- runFlow:
+    when:
+      true: ${REGION == 'United states'}
+    file: tap.yml
+    env:
+      TEXT: ${STATE}

.maestro/utils/set-timezone.yml

@@ -29,4 +29,5 @@ appId: com.android.settings
       visible: Region
     file: select-region.yml
     env:
-      TIMEZONE: ${TIMEZONE}
+      REGION: ${REGION}
+      STATE: ${STATE}

android/src/main/java/com/henninghall/date_picker/DatePickerManager.java

@@ -1,18 +1,10 @@
 package com.henninghall.date_picker;
 
 
-import android.app.AlertDialog;
-import android.app.Dialog;
-import android.app.DialogFragment;
-import android.content.DialogInterface;
-import android.os.Bundle;
-import android.view.View;
 import android.widget.LinearLayout;
 import android.widget.RelativeLayout;
 
 import com.facebook.react.bridge.Dynamic;
-import com.facebook.react.bridge.ReactApplicationContext;
-import com.facebook.react.bridge.ReactMethod;
 import com.facebook.react.bridge.ReadableArray;
 import com.facebook.react.common.MapBuilder;
 import com.facebook.react.uimanager.SimpleViewManager;
@@ -29,7 +21,7 @@
 import com.henninghall.date_picker.props.MinuteIntervalProp;
 import com.henninghall.date_picker.props.ModeProp;
 import com.henninghall.date_picker.props.TextColorProp;
-import com.henninghall.date_picker.props.UtcProp;
+import com.henninghall.date_picker.props.TimezoneOffsetInMinutesProp;
 
 
 import java.lang.reflect.Method;
@@ -54,7 +46,7 @@ public PickerView createViewInstance(ThemedReactContext context) {
   }
 
   @ReactPropGroup(names = { DateProp.name, ModeProp.name, LocaleProp.name, MaximumDateProp.name,
-          MinimumDateProp.name, FadeToColorProp.name, TextColorProp.name, UtcProp.name, MinuteIntervalProp.name,
+          MinimumDateProp.name, FadeToColorProp.name, TextColorProp.name, TimezoneOffsetInMinutesProp.name, MinuteIntervalProp.name,
           VariantProp.name, DividerHeightProp.name, Is24hourSourceProp.name
   })
   public void setProps(PickerView view, int index, Dynamic value) {

android/src/main/java/com/henninghall/date_picker/PickerView.java

@@ -11,7 +11,7 @@
 import com.henninghall.date_picker.props.MaximumDateProp;
 import com.henninghall.date_picker.props.MinimumDateProp;
 import com.henninghall.date_picker.props.MinuteIntervalProp;
-import com.henninghall.date_picker.props.UtcProp;
+import com.henninghall.date_picker.props.TimezoneOffsetInMinutesProp;
 import com.henninghall.date_picker.props.VariantProp;
 import com.henninghall.date_picker.props.DateProp;
 import com.henninghall.date_picker.props.FadeToColorProp;
@@ -77,7 +77,7 @@ public void update() {
 
         if (didUpdate(DateProp.name, HeightProp.name, LocaleProp.name,
                 MaximumDateProp.name, MinimumDateProp.name, MinuteIntervalProp.name, ModeProp.name,
-                UtcProp.name, VariantProp.name
+                TimezoneOffsetInMinutesProp.name, VariantProp.name
         )) {
             uiManager.updateDisplayValues();
         }

android/src/main/java/com/henninghall/date_picker/State.java

@@ -17,7 +17,9 @@
 import com.henninghall.date_picker.props.ModeProp;
 import com.henninghall.date_picker.props.Prop;
 import com.henninghall.date_picker.props.TextColorProp;
-import com.henninghall.date_picker.props.UtcProp;
+import com.henninghall.date_picker.props.TimezoneOffsetInMinutesProp;
+
+import net.time4j.tz.Timezone;
 
 import java.util.Calendar;
 import java.util.HashMap;
@@ -35,7 +37,7 @@ public class State {
     private final MinuteIntervalProp minuteIntervalProp = new MinuteIntervalProp();
     private final MinimumDateProp minimumDateProp = new MinimumDateProp();
     private final MaximumDateProp maximumDateProp = new MaximumDateProp();
-    private final UtcProp utcProp = new UtcProp();
+    private final TimezoneOffsetInMinutesProp timezoneOffsetInMinutesProp = new TimezoneOffsetInMinutesProp();
     private final HeightProp heightProp = new HeightProp();
     private final VariantProp variantProp = new VariantProp();
     private final DividerHeightProp dividerHeightProp = new DividerHeightProp();
@@ -50,7 +52,7 @@ public class State {
         put(MinuteIntervalProp.name, minuteIntervalProp);
         put(MinimumDateProp.name, minimumDateProp);
         put(MaximumDateProp.name, maximumDateProp);
-        put(UtcProp.name, utcProp);
+        put(TimezoneOffsetInMinutesProp.name, timezoneOffsetInMinutesProp);
         put(HeightProp.name, heightProp);
         put(VariantProp.name, variantProp);
         put(DividerHeightProp.name, dividerHeightProp);
@@ -91,18 +93,23 @@ public Locale getLocale() {
     }
 
     public Calendar getMinimumDate() {
-        DateBoundary db = new DateBoundary(getTimeZone(), (String) minimumDateProp.getValue());
-        return db.get();
+        return Utils.isoToCalendar(minimumDateProp.getValue(), getTimeZone());
     }
 
     public Calendar getMaximumDate() {
-        DateBoundary db = new DateBoundary(getTimeZone(), (String) maximumDateProp.getValue());
-        return db.get();
+        return Utils.isoToCalendar(maximumDateProp.getValue(), getTimeZone());
     }
 
     public TimeZone getTimeZone() {
-        boolean utc = (boolean) utcProp.getValue();
-        return utc ? TimeZone.getTimeZone("UTC") : TimeZone.getDefault();
+        Integer offset = timezoneOffsetInMinutesProp.getValue();
+        if(offset == null) return TimeZone.getDefault();
+        int totalOffsetMinutes = Math.abs(offset);
+        char offsetDirection = offset < 0 ? '-' : '+';
+        int offsetHours = (int) Math.floor(totalOffsetMinutes / 60f);
+        int offsetMinutes = totalOffsetMinutes - offsetHours * 60;
+        String timeZoneId = "GMT" + offsetDirection + offsetHours + ":" + Utils.toPaddedMinutes(offsetMinutes);
+        TimeZone zone = TimeZone.getTimeZone(timeZoneId);
+        return zone;
     }
 
     public String getIsoDate() {

android/src/main/java/com/henninghall/date_picker/Utils.java

@@ -9,6 +9,7 @@
 
 import net.time4j.PrettyTime;
 
+import java.text.DecimalFormat;
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
 import java.util.ArrayList;
@@ -110,4 +111,9 @@ public static String getLocalisedStringFromResources(Locale locale, String tagNa
     public static int toDp(int pixels){
         return (int) (pixels * DatePickerPackage.context.getResources().getDisplayMetrics().density);
     }
+
+    public static String toPaddedMinutes(int minutes){
+        DecimalFormat df = new DecimalFormat("00");
+        return df.format(minutes);
+    }
 }

android/src/main/java/com/henninghall/date_picker/props/TimezoneOffsetInMinutesProp.java

@@ -0,0 +1,13 @@
+package com.henninghall.date_picker.props;
+
+import com.facebook.react.bridge.Dynamic;
+
+public class TimezoneOffsetInMinutesProp extends Prop<Integer> {
+    public static final String name = "timezoneOffsetInMinutes";
+
+    @Override
+    Integer toValue(Dynamic value) {
+        if(value.isNull()) return null;
+        return value.asInt();
+    }
+}

android/src/main/java/com/henninghall/date_picker/wheels/DayWheel.java

@@ -50,10 +50,8 @@ private Calendar getStartCal(){
         Calendar min = state.getMinimumDate();
         if (min != null) {
             cal = (Calendar) min.clone();
-            resetToMidnight(cal);
         } else if (max != null) {
             cal = (Calendar) max.clone();
-            resetToMidnight(cal);
             cal.add(Calendar.DATE, -cal.getActualMaximum(Calendar.DAY_OF_YEAR) / 2);
         } else {
             cal = (Calendar) getInitialDate().clone();
@@ -68,10 +66,8 @@ private Calendar getEndCal(){
         Calendar min = state.getMinimumDate();
         if (max != null) {
             cal = (Calendar) max.clone();
-            resetToMidnight(cal);
         } else if (min != null) {
             cal = (Calendar) min.clone();
-            resetToMidnight(cal);
             cal.add(Calendar.DATE, cal.getActualMaximum(Calendar.DAY_OF_YEAR) / 2);
         } else {
             cal = (Calendar) getInitialDate().clone();

src/DatePickerAndroid.js

@@ -46,10 +46,15 @@ class DatePickerAndroid extends React.PureComponent {
     date: this._date(),
     minimumDate: this._minimumDate(),
     maximumDate: this._maximumDate(),
-    utc: this.props.timeZoneOffsetInMinutes !== undefined,
+    timezoneOffsetInMinutes: this._getTimezoneOffsetInMinutes(),
     style: this._getStyle(),
   })
 
+  _getTimezoneOffsetInMinutes = () => {
+    if (this.props.timeZoneOffsetInMinutes == undefined) return undefined
+    return this.props.timeZoneOffsetInMinutes
+  }
+
   _getStyle = () => {
     const width = this.props.mode === 'time' ? timeModeWidth : defaultWidth
     return [{ width, height }, this.props.style]
@@ -74,16 +79,11 @@ class DatePickerAndroid extends React.PureComponent {
   _date = () => this._toIsoWithTimeZoneOffset(this.props.date)
 
   _fromIsoWithTimeZoneOffset = (timestamp) => {
-    const date = new Date(timestamp)
-    if (this.props.timeZoneOffsetInMinutes === undefined) return date
-    return addMinutes(date, -this.props.timeZoneOffsetInMinutes)
+    return new Date(timestamp)
   }
 
   _toIsoWithTimeZoneOffset = (date) => {
-    if (this.props.timeZoneOffsetInMinutes === undefined)
-      return date.toISOString()
-
-    return addMinutes(date, this.props.timeZoneOffsetInMinutes).toISOString()
+    return date.toISOString()
   }
 
   _onConfirm = (isoDate) => {