diff --git a/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatDialog.java b/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatDialog.java
index fbe10a53..53f623c2 100644
--- a/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatDialog.java
+++ b/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatDialog.java
@@ -1,3 +1,19 @@
+/*
+ * Copyright (c) 2019 yvolk (Yuri Volkov), http://yurivolkov.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
 package org.andstatus.todoagenda.prefs.dateformat;
 
 import android.content.Context;
@@ -26,9 +42,6 @@
 import java.util.Date;
 import java.util.Locale;
 
-/**
- * @author yvolk@yurivolkov.com
- */
 public class DateFormatDialog extends PreferenceDialogFragmentCompat implements AdapterView.OnItemSelectedListener, View.OnKeyListener, TextWatcher {
     private final DateFormatPreference preference;
     private Spinner typeSpinner;
@@ -126,13 +139,17 @@ private DateFormatValue getValue() {
     }
 
     private void calcResult() {
+        DateFormatValue dateFormatValue = getValue();
         SimpleDateFormat sampleFormat = getSampleDateFormat();
         CharSequence result;
         try {
+            if (customPatternText.isEnabled() != (dateFormatValue.type == DateFormatType.CUSTOM)) {
+                customPatternText.setEnabled(dateFormatValue.type == DateFormatType.CUSTOM);
+            }
             Date sampleDate = sampleFormat.parse(sampleDateText.getText().toString());
             result = sampleDate == null
                     ? "null"
-                    : new DateFormatter(this.getContext(), getValue(), getSettings().clock().now())
+                    : new DateFormatter(this.getContext(), dateFormatValue, getSettings().clock().now())
                         .formatMillis(sampleDate.getTime());
         } catch (ParseException e) {
             result = e.getLocalizedMessage();
diff --git a/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatPreference.java b/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatPreference.java
index d42d8ac3..0643164b 100644
--- a/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatPreference.java
+++ b/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatPreference.java
@@ -1,3 +1,19 @@
+/*
+ * Copyright (c) 2019 yvolk (Yuri Volkov), http://yurivolkov.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
 package org.andstatus.todoagenda.prefs.dateformat;
 
 import android.content.Context;
@@ -10,9 +26,6 @@
 
 import org.andstatus.todoagenda.prefs.ApplicationPreferences;
 
-/**
- * @author yvolk@yurivolkov.com
- */
 public class DateFormatPreference extends DialogPreference {
     DateFormatValue defaultValue = DateFormatType.unknownValue();
     DateFormatValue value = DateFormatType.unknownValue();
@@ -63,4 +76,4 @@ public void setValue(DateFormatValue value) {
     private void showValue() {
         setSummary(getSummary());
     }
-}
+}
\ No newline at end of file
diff --git a/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatType.java b/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatType.java
index 38e9a4ca..bc278db0 100644
--- a/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatType.java
+++ b/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatType.java
@@ -1,3 +1,19 @@
+/*
+ * Copyright (c) 2019 yvolk (Yuri Volkov), http://yurivolkov.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
 package org.andstatus.todoagenda.prefs.dateformat;
 
 import android.content.Context;
@@ -11,19 +27,18 @@
 import java.util.ArrayList;
 import java.util.List;
 
-/** See https://github.com/andstatus/todoagenda/issues/7
- *  @author yvolk@yurivolkov.com
- * */
+/** See https://github.com/andstatus/todoagenda/issues/7 */
 public enum DateFormatType {
     HIDDEN("hidden", R.string.hidden, ""),
     DEVICE_DEFAULT("deviceDefault", R.string.device_default, ""),
     DEFAULT_WEEKDAY("defaultWeekday", R.string.date_format_default_weekday, ""),
     DEFAULT_DAYS("defaultDays", R.string.date_format_default_days, ""),
     ABBREVIATED("abbrev", R.string.appearance_abbreviate_dates_title, ""),
-    NUMBER_OF_DAYS("days", R.string.date_format_number_of_days_to_event, ""),
+    NUMBER_OF_DAYS("days", R.string.date_format_number_of_days_to_event, "bbbbb"),
     DAY_IN_MONTH("dayInMonth", R.string.date_format_day_in_month, "dd"),
     MONTH_DAY("monthDay", R.string.date_format_month_day, "MM-dd"),
-    WEEK_YEAR("weekInYear", R.string.date_format_week_in_year, "ww"),
+    WEEK_IN_YEAR("weekInYear", R.string.date_format_week_in_year, "ww"),
+    PATTERN_EXAMPLE1("example1", R.string.pattern_example, "b EEE, d MMM yyyy 'W'ww"),
     CUSTOM("custom-01", R.string.custom_pattern, ""),
     UNKNOWN("unknown", R.string.not_found, "");
 
diff --git a/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatValue.java b/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatValue.java
index 939aa306..a7eee3d6 100644
--- a/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatValue.java
+++ b/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatValue.java
@@ -1,3 +1,19 @@
+/*
+ * Copyright (c) 2019 yvolk (Yuri Volkov), http://yurivolkov.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
 package org.andstatus.todoagenda.prefs.dateformat;
 
 import android.content.Context;
@@ -8,9 +24,6 @@
 
 import static org.andstatus.todoagenda.prefs.dateformat.DateFormatType.CUSTOM;
 
-/**
- * @author yvolk@yurivolkov.com
- */
 public class DateFormatValue {
     public final DateFormatType type;
     public final String value;
@@ -52,6 +65,6 @@ public String getPattern() {
     }
 
     public CharSequence getSummary(Context context) {
-        return context.getText(type.titleResourceId) + (type == CUSTOM ? ": \"" + value + "\"" : "");
+        return context.getText(type.titleResourceId) + (type == CUSTOM ? ": " + value : "");
     }
 }
diff --git a/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatter.java b/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatter.java
index a648b5d7..f88d2106 100644
--- a/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatter.java
+++ b/app/src/main/java/org/andstatus/todoagenda/prefs/dateformat/DateFormatter.java
@@ -1,3 +1,19 @@
+/*
+ * Copyright (c) 2019 yvolk (Yuri Volkov), http://yurivolkov.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
 package org.andstatus.todoagenda.prefs.dateformat;
 
 import android.content.Context;
@@ -13,10 +29,8 @@
 import java.util.Formatter;
 import java.util.Locale;
 
-/**
- * @author yvolk@yurivolkov.com
- */
 public class DateFormatter {
+    private static final char NUMBER_OF_DAYS_LETTER = 'b';
     private final Context context;
     private final DateFormatValue dateFormatValue;
     private final DateTime now;
@@ -45,10 +59,10 @@ public CharSequence formatMillis(long millis) {
                     return formatDateTime(millis, DateUtils.FORMAT_ABBREV_ALL | DateUtils.FORMAT_SHOW_DATE |
                             DateUtils.FORMAT_SHOW_WEEKDAY);
                 case DEFAULT_DAYS:
-                    return getDaysFromTodayString(context, getDaysFromToday(millis)) + ", " +
+                    return getDaysFromTodayString(context, 5, getDaysFromToday(millis)) + ", " +
                             formatDateTime(millis, DateUtils.FORMAT_SHOW_DATE);
                 case NUMBER_OF_DAYS:
-                    return getDaysFromTodayString(context, getDaysFromToday(millis));
+                    return getDaysFromTodayString(context, 5, getDaysFromToday(millis));
                 default:
                     return "(not implemented)";
             }
@@ -67,17 +81,20 @@ private String formatDateTime(long millis, int flags) {
                 .toString();
     }
 
-    public static CharSequence getDaysFromTodayString(Context context, int daysFromToday) {
-        switch (daysFromToday) {
-            case -1:
-                return context.getText(R.string.yesterday);
-            case 0:
-                return context.getText(R.string.today);
-            case 1:
-                return context.getText(R.string.tomorrow);
-            default:
-                return Math.abs(daysFromToday) > 9999 ? "..." : Integer.toString(daysFromToday);
+    public static CharSequence getDaysFromTodayString(Context context, int formatLength, int daysFromToday) {
+        if (formatLength > 4) {
+            switch (daysFromToday) {
+                case -1:
+                    return context.getText(R.string.yesterday);
+                case 0:
+                    return context.getText(R.string.today);
+                case 1:
+                    return context.getText(R.string.tomorrow);
+                default:
+                    break;
+            }
         }
+        return Math.abs(daysFromToday) > 9999 ? "..." : Integer.toString(daysFromToday);
     }
 
     public int getDaysFromToday(long millis) {
@@ -87,7 +104,8 @@ public int getDaysFromToday(long millis) {
 
     private String formatDateCustom(long millis, String pattern) {
         try {
-            SimpleDateFormat format = new SimpleDateFormat(pattern, locale);
+            String pattern2 = preProcessNumberOfDaysToEvent(millis, pattern);
+            SimpleDateFormat format = new SimpleDateFormat(pattern2, locale);
             Date date = new Date(millis);
             return format.format(date);
         } catch (Exception e) {
@@ -95,4 +113,17 @@ private String formatDateCustom(long millis, String pattern) {
         }
     }
 
+    private String preProcessNumberOfDaysToEvent(long millis, String pattern) {
+        int ind1 = pattern.indexOf(NUMBER_OF_DAYS_LETTER);
+        if (ind1 < 0) return pattern;
+        int ind2 = ind1;
+        while (ind2 < pattern.length() && pattern.charAt(ind2) == NUMBER_OF_DAYS_LETTER) {
+            ind2++;
+        }
+        CharSequence result = getDaysFromTodayString(context, ind2 - ind1, getDaysFromToday(millis));
+        return (ind1 > 0 ? pattern.substring(0, ind1) : "") +
+               "'" + result + "'" +
+               (ind2 < pattern.length() ? pattern.substring(ind2) : "");
+    }
+
 }
\ No newline at end of file
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index b4f3f4d7..948eea61 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -107,6 +107,7 @@
     <string name="date_format_day_in_month">Day in month</string>
     <string name="date_format_month_day">Month-Day</string>
     <string name="date_format_week_in_year">Week in year</string>
+    <string name="pattern_example">Pattern example</string>
     <string name="custom_pattern">Custom pattern</string>
     <string name="sample_date">Sample date (in yyyy-MM-dd format)</string>
     <string name="result_formatted_date">Result, formatted date</string>