Added option to disable two column mode

app/src/main/java/eu/faircode/email/ActivityView.java

@@ -78,6 +78,8 @@ import java.util.List;
 
 import javax.net.ssl.HttpsURLConnection;
 
+import static android.content.res.Configuration.ORIENTATION_PORTRAIT;
+
 public class ActivityView extends ActivityBilling implements FragmentManager.OnBackStackChangedListener {
     private String startup;
 
@@ -133,7 +135,15 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
         final SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
         startup = prefs.getString("startup", "unified");
 
-        view = LayoutInflater.from(this).inflate(R.layout.activity_view, null);
+        Configuration config = getResources().getConfiguration();
+        boolean normal = config.isLayoutSizeAtLeast(Configuration.SCREENLAYOUT_SIZE_NORMAL);
+        boolean landscape = prefs.getBoolean("landscape", true);
+        Log.i("Orientation=" + config.orientation + " normal=" + normal + " landscape=" + landscape);
+
+        view = LayoutInflater.from(this).inflate(
+                config.orientation == ORIENTATION_PORTRAIT || !normal || !landscape
+                        ? R.layout.activity_view_portrait
+                        : R.layout.activity_view_landscape, null);
         setContentView(view);
 
         getSupportActionBar().setDisplayHomeAsUpEnabled(true);

app/src/main/java/eu/faircode/email/FragmentOptions.java

@@ -39,7 +39,7 @@ public class FragmentOptions extends FragmentBase {
 
     static String[] OPTIONS_RESTART = new String[]{
             "subscriptions",
-            "startup", "cards", "date", "threading", "indentation", "highlight_unread",
+            "landscape", "startup", "cards", "date", "threading", "indentation", "highlight_unread",
             "avatars", "generated_icons", "identicons", "circular", "saturation", "brightness", "threshold",
             "name_email", "distinguish_contacts", "authentication",
             "subject_top", "subject_italic", "subject_ellipsize",

app/src/main/java/eu/faircode/email/FragmentOptionsDisplay.java

@@ -22,6 +22,7 @@ package eu.faircode.email;
 import android.app.Dialog;
 import android.content.Context;
 import android.content.SharedPreferences;
+import android.content.res.Configuration;
 import android.graphics.Bitmap;
 import android.os.Bundle;
 import android.view.LayoutInflater;
@@ -48,6 +49,7 @@ import androidx.preference.PreferenceManager;
 
 public class FragmentOptionsDisplay extends FragmentBase implements SharedPreferences.OnSharedPreferenceChangeListener {
     private Button btnTheme;
+    private SwitchCompat swLandscape;
     private Spinner spStartup;
     private SwitchCompat swCards;
     private SwitchCompat swDate;
@@ -86,7 +88,7 @@ public class FragmentOptionsDisplay extends FragmentBase implements SharedPrefer
     private SwitchCompat swActionbar;
 
     private final static String[] RESET_OPTIONS = new String[]{
-            "theme", "startup", "cards", "date", "threading", "indentation", "highlight_unread",
+            "theme", "landscape", "startup", "cards", "date", "threading", "indentation", "highlight_unread",
             "avatars", "generated_icons", "identicons", "circular", "saturation", "brightness", "threshold",
             "name_email", "distinguish_contacts", "authentication",
             "subject_top", "subject_italic", "subject_ellipsize",
@@ -106,6 +108,7 @@ public class FragmentOptionsDisplay extends FragmentBase implements SharedPrefer
         // Get controls
 
         btnTheme = view.findViewById(R.id.btnTheme);
+        swLandscape = view.findViewById(R.id.swLandscape);
         spStartup = view.findViewById(R.id.spStartup);
         swCards = view.findViewById(R.id.swCards);
         swDate = view.findViewById(R.id.swDate);
@@ -155,6 +158,13 @@ public class FragmentOptionsDisplay extends FragmentBase implements SharedPrefer
             }
         });
 
+        swLandscape.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
+            @Override
+            public void onCheckedChanged(CompoundButton compoundButton, boolean checked) {
+                prefs.edit().putBoolean("landscape", checked).apply();
+            }
+        });
+
         spStartup.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
             @Override
             public void onItemSelected(AdapterView<?> adapterView, View view, int position, long id) {
@@ -486,6 +496,12 @@ public class FragmentOptionsDisplay extends FragmentBase implements SharedPrefer
     private void setOptions() {
         SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(getContext());
 
+        boolean normal = getResources().getConfiguration()
+                .isLayoutSizeAtLeast(Configuration.SCREENLAYOUT_SIZE_NORMAL);
+
+        swLandscape.setChecked(prefs.getBoolean("landscape", true));
+        swLandscape.setEnabled(normal);
+
         String startup = prefs.getString("startup", "unified");
         String[] startupValues = getResources().getStringArray(R.array.startupValues);
         for (int pos = 0; pos < startupValues.length; pos++)

app/src/main/res/layout/fragment_options_display.xml

@@ -35,6 +35,18 @@
             app:layout_constraintStart_toStartOf="parent"
             app:layout_constraintTop_toBottomOf="@id/tvLayoutHint" />
 
+        <androidx.appcompat.widget.SwitchCompat
+            android:id="@+id/swLandscape"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="12dp"
+            android:checked="true"
+            android:text="@string/title_advanced_landscape"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@id/btnTheme"
+            app:switchPadding="12dp" />
+
         <TextView
             android:id="@+id/tvStartup"
             android:layout_width="0dp"
@@ -45,7 +57,7 @@
             android:textColor="?android:attr/textColorPrimary"
             app:layout_constraintEnd_toEndOf="parent"
             app:layout_constraintStart_toStartOf="parent"
-            app:layout_constraintTop_toBottomOf="@id/btnTheme" />
+            app:layout_constraintTop_toBottomOf="@id/swLandscape" />
 
         <Spinner
             android:id="@+id/spStartup"

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

@@ -241,6 +241,7 @@
     <string name="title_advanced_rlah">Roam like at home</string>
     <string name="title_advanced_manage_connectivity">Manage connectivity</string>
 
+    <string name="title_advanced_landscape">Use two columns in landscape mode</string>
     <string name="title_advanced_startup">Show on start screen</string>
     <string name="title_advanced_cards">Show cards</string>
     <string name="title_advanced_date_header">Group by date</string>