From 8744724c0f2df6dcda6e784a5bb8381949cf81fd Mon Sep 17 00:00:00 2001
From: Dennis Guse <dennis.guse@alumni.tu-berlin.de>
Date: Tue, 24 Jun 2025 11:36:44 +0200
Subject: [PATCH] Enable to edit timezone offset for recorded tracks.

Fixes #2014.
---
 .../opentracks/TrackEditActivity.java         | 10 ++++++++--
 .../opentracks/data/models/Track.java         |  8 ++++++--
 .../opentracks/ui/ZoneOffsetAdapter.java      | 19 +++++++++++++++++++
 src/main/res/layout/track_edit.xml            | 19 +++++++++++++++++++
 src/main/res/values/strings.xml               |  1 +
 5 files changed, 53 insertions(+), 4 deletions(-)
 create mode 100644 src/main/java/de/dennisguse/opentracks/ui/ZoneOffsetAdapter.java

diff --git a/src/main/java/de/dennisguse/opentracks/TrackEditActivity.java b/src/main/java/de/dennisguse/opentracks/TrackEditActivity.java
index da3969bf3..b6035d705 100644
--- a/src/main/java/de/dennisguse/opentracks/TrackEditActivity.java
+++ b/src/main/java/de/dennisguse/opentracks/TrackEditActivity.java
@@ -23,11 +23,14 @@ import android.widget.ArrayAdapter;
 
 import androidx.annotation.NonNull;
 
+import java.time.ZoneOffset;
+
 import de.dennisguse.opentracks.data.ContentProviderUtils;
 import de.dennisguse.opentracks.data.models.ActivityType;
 import de.dennisguse.opentracks.data.models.Track;
 import de.dennisguse.opentracks.databinding.TrackEditBinding;
 import de.dennisguse.opentracks.fragments.ChooseActivityTypeDialogFragment;
+import de.dennisguse.opentracks.ui.ZoneOffsetAdapter;
 import de.dennisguse.opentracks.util.TrackUtils;
 
 /**
@@ -71,7 +74,6 @@ public class TrackEditActivity extends AbstractActivity implements ChooseActivit
         viewBinding.trackEditName.setText(track.getName());
 
         viewBinding.trackEditActivityType.setText(track.getActivityTypeLocalized());
-
         ArrayAdapter<String> adapter = new ArrayAdapter<>(this, android.R.layout.simple_dropdown_item_1line, ActivityType.getLocalizedStrings(this));
         viewBinding.trackEditActivityType.setAdapter(adapter);
         viewBinding.trackEditActivityType.setOnItemClickListener((parent, view, position, id) -> {
@@ -92,12 +94,16 @@ public class TrackEditActivity extends AbstractActivity implements ChooseActivit
         if (activityType == null) {
             activityType = track.getActivityType();
         }
-
         setActivityTypeIcon(activityType);
         viewBinding.trackEditActivityTypeIcon.setOnClickListener(v -> ChooseActivityTypeDialogFragment.showDialog(getSupportFragmentManager(), this, viewBinding.trackEditActivityType.getText().toString()));
 
         viewBinding.trackEditDescription.setText(track.getDescription());
 
+        final ArrayAdapter<ZoneOffset> zoneOffsetAdapter = new ZoneOffsetAdapter(this, android.R.layout.simple_dropdown_item_1line);
+        viewBinding.trackEditTimeOffset.setText(track.getZoneOffset().toString());
+        viewBinding.trackEditTimeOffset.setAdapter(zoneOffsetAdapter);
+        viewBinding.trackEditTimeOffset.setOnItemClickListener((parent, view, position, id) -> track.setZoneOffset(zoneOffsetAdapter.getItem(position)));
+
         viewBinding.trackEditSave.setOnClickListener(v -> {
             TrackUtils.updateTrack(TrackEditActivity.this, track, viewBinding.trackEditName.getText().toString(),
                     viewBinding.trackEditActivityType.getText().toString(), viewBinding.trackEditDescription.getText().toString(),
diff --git a/src/main/java/de/dennisguse/opentracks/data/models/Track.java b/src/main/java/de/dennisguse/opentracks/data/models/Track.java
index 625f276cd..9703de43d 100644
--- a/src/main/java/de/dennisguse/opentracks/data/models/Track.java
+++ b/src/main/java/de/dennisguse/opentracks/data/models/Track.java
@@ -48,7 +48,7 @@ public class Track {
 
     private ActivityType activityType;
 
-    private final ZoneOffset zoneOffset;
+    private ZoneOffset zoneOffset;
 
     private TrackStatistics trackStatistics = new TrackStatistics();
 
@@ -58,7 +58,7 @@ public class Track {
     }
 
     public Track(@NonNull ZoneOffset zoneOffset) {
-        this.zoneOffset = zoneOffset;
+        setZoneOffset(zoneOffset);
     }
 
     /**
@@ -117,6 +117,10 @@ public class Track {
         return zoneOffset;
     }
 
+    public void setZoneOffset(@NonNull ZoneOffset zoneOffset) {
+        this.zoneOffset = zoneOffset;
+    }
+
     public OffsetDateTime getStartTime() {
         return trackStatistics
                 .getStartTime().atOffset(zoneOffset);
diff --git a/src/main/java/de/dennisguse/opentracks/ui/ZoneOffsetAdapter.java b/src/main/java/de/dennisguse/opentracks/ui/ZoneOffsetAdapter.java
new file mode 100644
index 000000000..9ae5148b0
--- /dev/null
+++ b/src/main/java/de/dennisguse/opentracks/ui/ZoneOffsetAdapter.java
@@ -0,0 +1,19 @@
+package de.dennisguse.opentracks.ui;
+
+
+import android.content.Context;
+import android.widget.ArrayAdapter;
+
+import androidx.annotation.NonNull;
+
+import java.time.ZoneOffset;
+import java.util.stream.IntStream;
+
+public class ZoneOffsetAdapter extends ArrayAdapter<ZoneOffset> {
+    public ZoneOffsetAdapter(@NonNull Context context, int resource) {
+        super(context, resource, IntStream.range(-12, +12)
+                .boxed()
+                .map(ZoneOffset::ofHours)
+                .toList());
+    }
+}
diff --git a/src/main/res/layout/track_edit.xml b/src/main/res/layout/track_edit.xml
index 42e90a66d..cb4d630fe 100644
--- a/src/main/res/layout/track_edit.xml
+++ b/src/main/res/layout/track_edit.xml
@@ -79,6 +79,25 @@ limitations under the License.
                         android:layout_gravity="bottom" />
                 </LinearLayout>
 
+                <com.google.android.material.textfield.TextInputLayout
+                    style="?attr/textInputOutlinedExposedDropdownMenuStyle"
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:layout_marginBottom="16dp"
+                    android:imeOptions="actionNext"
+                    android:importantForAutofill="no">
+
+                    <com.google.android.material.textfield.MaterialAutoCompleteTextView
+                        android:id="@+id/track_edit_time_offset"
+                        android:layout_width="match_parent"
+                        android:inputType="none"
+                        android:layout_height="wrap_content"
+                        android:layout_marginEnd="8dp"
+                        android:hint="@string/track_edit_time_offset"
+                        android:imeOptions="actionNext"
+                        android:selectAllOnFocus="true" />
+                </com.google.android.material.textfield.TextInputLayout>
+
                 <com.google.android.material.textfield.TextInputLayout
                     style="?attr/textInputOutlinedStyle"
                     android:layout_width="match_parent"
diff --git a/src/main/res/values/strings.xml b/src/main/res/values/strings.xml
index f8b589d1a..600f4fe96 100644
--- a/src/main/res/values/strings.xml
+++ b/src/main/res/values/strings.xml
@@ -491,6 +491,7 @@ limitations under the License.
     <!-- Track Edit -->
     <string name="track_edit_activity_type">Activity type (e.g. hiking)</string>
     <string name="track_edit_activity_type_hint">Activity type</string>
+    <string name="track_edit_time_offset">Timezone Offset</string>
     <!-- Track List -->
     <string name="track_list_empty_message">Start recording your next adventure here</string>
     <!-- Aggregated Statistics -->