integrate into egui

egui_demo_lib/src/apps/demo/widget_gallery.rs

@@ -1,3 +1,8 @@
+use egui_datepicker::DatePickerButton;
+
+#[cfg(feature = "datetime")]
+mod serde_date_format;
+
 #[derive(Debug, PartialEq)]
 #[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 enum Enum {
@@ -17,6 +22,9 @@ pub struct WidgetGallery {
     string: String,
     color: egui::Color32,
     animate_progress_bar: bool,
+    #[cfg(feature = "datetime")]
+    #[serde(with = "serde_date_format")]
+    date: chrono::Date<chrono::Utc>,
 }
 
 impl Default for WidgetGallery {
@@ -30,6 +38,8 @@ impl Default for WidgetGallery {
             string: Default::default(),
             color: egui::Color32::LIGHT_BLUE.linear_multiply(0.5),
             animate_progress_bar: false,
+            #[cfg(feature = "datetime")]
+            date: chrono::offset::Utc::now().date(),
         }
     }
 }
@@ -99,6 +109,7 @@ impl WidgetGallery {
             string,
             color,
             animate_progress_bar,
+            date,
         } = self;
 
         ui.add(doc_link_label("Label", "label,heading"));
@@ -195,6 +206,13 @@ impl WidgetGallery {
         }
         ui.end_row();
 
+        #[cfg(feature = "datetime")]
+        {
+            ui.add(doc_link_label("DatePickerButton", "DatePickerButton"));
+            ui.add(DatePickerButton::new(date));
+            ui.end_row();
+        }
+
         ui.add(doc_link_label("Separator", "separator"));
         ui.separator();
         ui.end_row();

egui_demo_lib/src/apps/demo/widget_gallery/serde_date_format.rs

@@ -0,0 +1,23 @@
+use chrono::{Date, NaiveDate, Utc};
+use serde::{self, Deserialize, Deserializer, Serializer};
+
+const FORMAT: &str = "%d.%m.%Y";
+
+pub fn serialize<S>(date: &Date<Utc>, serializer: S) -> Result<S::Ok, S::Error>
+where
+    S: Serializer,
+{
+    let s = format!("{}", date.format(FORMAT));
+    serializer.serialize_str(&s)
+}
+
+pub fn deserialize<'de, D>(deserializer: D) -> Result<Date<Utc>, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    let s = String::deserialize(deserializer)?;
+
+    NaiveDate::parse_from_str(&s, FORMAT)
+        .map(|naive_date| Date::from_utc(naive_date, Utc))
+        .map_err(serde::de::Error::custom)
+}