Added setting for number of preview lines

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

@@ -200,6 +200,7 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
     private boolean flags_background;
     private boolean preview;
     private boolean preview_italic;
+    private int preview_lines;
     private boolean attachments_alt;
     private boolean contrast;
     private boolean monospaced;
@@ -828,6 +829,7 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
             if (tvPreview.getTag() == null || (int) tvPreview.getTag() != textColor) {
                 tvPreview.setTag(textColor);
                 tvPreview.setTextColor(textColor);
+                tvPreview.setMaxLines(preview_lines);
             }
             tvPreview.setTypeface(
                     monospaced ? Typeface.MONOSPACE : Typeface.DEFAULT,
@@ -3550,6 +3552,7 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
         this.flags_background = prefs.getBoolean("flags_background", false);
         this.preview = prefs.getBoolean("preview", false);
         this.preview_italic = prefs.getBoolean("preview_italic", true);
+        this.preview_lines = prefs.getInt("preview_lines", 2);
         this.attachments_alt = prefs.getBoolean("attachments_alt", false);
         this.contrast = prefs.getBoolean("contrast", false);
         this.monospaced = prefs.getBoolean("monospaced", false);

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

@@ -43,7 +43,7 @@ public class FragmentOptions extends FragmentBase {
             "avatars", "generated_icons", "identicons", "circular", "saturation", "brightness", "threshold",
             "name_email", "distinguish_contacts", "authentication",
             "subject_top", "subject_italic", "subject_ellipsize",
-            "flags", "flags_background", "preview", "preview_italic",
+            "flags", "flags_background", "preview", "preview_italic", "preview_lines",
             "addresses", "attachments_alt",
             "contrast", "monospaced", "text_color",
             "inline_images", "collapse_quotes", "seekbar", "actionbar",

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

@@ -76,6 +76,7 @@ public class FragmentOptionsDisplay extends FragmentBase implements SharedPrefer
     private SwitchCompat swFlagsBackground;
     private SwitchCompat swPreview;
     private SwitchCompat swPreviewItalic;
+    private Spinner spPreviewLines;
     private SwitchCompat swAddresses;
     private SwitchCompat swAttachmentsAlt;
 
@@ -92,7 +93,7 @@ public class FragmentOptionsDisplay extends FragmentBase implements SharedPrefer
             "avatars", "generated_icons", "identicons", "circular", "saturation", "brightness", "threshold",
             "name_email", "distinguish_contacts", "authentication",
             "subject_top", "subject_italic", "subject_ellipsize",
-            "flags", "flags_background", "preview", "preview_italic", "addresses", "attachments_alt",
+            "flags", "flags_background", "preview", "preview_italic", "preview_lines", "addresses", "attachments_alt",
             "contrast", "monospaced", "text_color",
             "inline_images", "collapse_quotes", "seekbar", "actionbar",
     };
@@ -135,6 +136,7 @@ public class FragmentOptionsDisplay extends FragmentBase implements SharedPrefer
         swFlagsBackground = view.findViewById(R.id.swFlagsBackground);
         swPreview = view.findViewById(R.id.swPreview);
         swPreviewItalic = view.findViewById(R.id.swPreviewItalic);
+        spPreviewLines = view.findViewById(R.id.spPreviewLines);
         swAddresses = view.findViewById(R.id.swAddresses);
         swAttachmentsAlt = view.findViewById(R.id.swAttachmentsAlt);
         swContrast = view.findViewById(R.id.swContrast);
@@ -378,6 +380,7 @@ public class FragmentOptionsDisplay extends FragmentBase implements SharedPrefer
             public void onCheckedChanged(CompoundButton compoundButton, boolean checked) {
                 prefs.edit().putBoolean("preview", checked).apply();
                 swPreviewItalic.setEnabled(checked);
+                spPreviewLines.setEnabled(checked);
             }
         });
 
@@ -388,6 +391,18 @@ public class FragmentOptionsDisplay extends FragmentBase implements SharedPrefer
             }
         });
 
+        spPreviewLines.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
+            @Override
+            public void onItemSelected(AdapterView<?> adapterView, View view, int position, long id) {
+                prefs.edit().putInt("preview_lines", position + 1).apply();
+            }
+
+            @Override
+            public void onNothingSelected(AdapterView<?> parent) {
+                prefs.edit().remove("preview_lines").apply();
+            }
+        });
+
         swAddresses.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
             @Override
             public void onCheckedChanged(CompoundButton compoundButton, boolean checked) {
@@ -549,6 +564,8 @@ public class FragmentOptionsDisplay extends FragmentBase implements SharedPrefer
         swPreview.setChecked(prefs.getBoolean("preview", false));
         swPreviewItalic.setChecked(prefs.getBoolean("preview_italic", true));
         swPreviewItalic.setEnabled(swPreview.isChecked());
+        spPreviewLines.setSelection(prefs.getInt("preview_lines", 2) - 1);
+        spPreviewLines.setEnabled(swPreview.isChecked());
         swAddresses.setChecked(prefs.getBoolean("addresses", false));
         swAttachmentsAlt.setChecked(prefs.getBoolean("attachments_alt", false));
         swContrast.setChecked(prefs.getBoolean("contrast", false));

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

@@ -68,7 +68,7 @@ import static androidx.core.text.HtmlCompat.FROM_HTML_SEPARATOR_LINE_BREAK_LIST_
 import static androidx.core.text.HtmlCompat.TO_HTML_PARAGRAPH_LINES_CONSECUTIVE;
 
 public class HtmlHelper {
-    private static final int PREVIEW_SIZE = 250; // characters
+    private static final int PREVIEW_SIZE = 500; // characters
 
     private static final float MIN_LUMINANCE = 0.5f;
     private static final int MAX_AUTO_LINK = 250;

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

@@ -460,6 +460,27 @@
             app:layout_constraintTop_toBottomOf="@id/tvPreviewHint"
             app:switchPadding="12dp" />
 
+        <TextView
+            android:id="@+id/tvPreviewLines"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="12dp"
+            android:text="@string/title_advanced_preview_lines"
+            android:textAppearance="@style/Base.TextAppearance.AppCompat.Small"
+            android:textColor="?android:attr/textColorPrimary"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@id/swPreviewItalic" />
+
+        <Spinner
+            android:id="@+id/spPreviewLines"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="12dp"
+            android:entries="@array/linesNames"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@id/tvPreviewLines" />
+
         <androidx.appcompat.widget.SwitchCompat
             android:id="@+id/swAddresses"
             android:layout_width="0dp"
@@ -468,7 +489,7 @@
             android:text="@string/title_advanced_addresses"
             app:layout_constraintEnd_toEndOf="parent"
             app:layout_constraintStart_toStartOf="parent"
-            app:layout_constraintTop_toBottomOf="@id/swPreviewItalic"
+            app:layout_constraintTop_toBottomOf="@id/spPreviewLines"
             app:switchPadding="12dp" />
 
         <androidx.appcompat.widget.SwitchCompat

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

@@ -266,6 +266,7 @@
     <string name="title_advanced_flags_background">Show colored background instead of colored stars</string>
     <string name="title_advanced_preview">Show message preview</string>
     <string name="title_advanced_preview_italic">Show message preview in italics</string>
+    <string name="title_advanced_preview_lines">Number of preview lines</string>
     <string name="title_advanced_addresses">Show address details by default</string>
     <string name="title_advanced_attachments_alt">Show attachments after the message text</string>
     <string name="title_advanced_contrast">Use high contrast for message text</string>
@@ -1076,6 +1077,13 @@
         <item>High</item>
     </string-array>
 
+    <string-array name="linesNames">
+        <item>1</item>
+        <item>2</item>
+        <item>3</item>
+        <item>4</item>
+    </string-array>
+
     <string name="fingerprint" translatable="false">17BA15C1AF55D925F98B99CEA4375D4CDF4C174B</string>
     <string name="public_key" translatable="false">MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAtFbxEbzL8u5accPGgBw/XdyiSS5BBE6ZQ9ELpKyJ/OQN+kdYniCAOw3lsQ/GuJScy4Y2HobqbBgLL8GLHG+Yu2EHC9dLjA3v2Mc25vvnfn86BsrpQvz1poN2n+roTBdq09FWbtebJ8m0hDBVmtfRi7RhTKIL4No3kodLhksdnucKjcFheubebWKgpmvbmw7NwuELhaZmyhw8WTtnQ4rZPMhjY1JJZgzwNExXgD7zzg4pJPkuQlfkuRkkvBpHpi3C7VDnYjrBlLHngI4wv3wxQBVwJqlvAT9PmX8dOVnTsWWdJdLQBZVWphuqVY54kjBIovN+o8w03WjsV9QiOQq+XwIDAQAB</string>
 </resources>