Show correct time

Cargo.lock

@@ -108,6 +108,19 @@ version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
+[[package]]
+name = "chrono"
+version = "0.4.19"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "670ad68c9088c2a963aaa298cb369688cf3f9465ce5e2d4ca10e6e0098a1ce73"
+dependencies = [
+ "libc",
+ "num-integer",
+ "num-traits",
+ "time",
+ "winapi",
+]
+
 [[package]]
 name = "concurrent-queue"
 version = "1.2.2"
@@ -122,6 +135,7 @@ name = "cosmic-panel"
 version = "0.1.0"
 dependencies = [
  "cascade",
+ "chrono",
  "gdk4-x11",
  "gtk4",
  "toml",
@@ -658,6 +672,25 @@ dependencies = [
  "void",
 ]
 
+[[package]]
+name = "num-integer"
+version = "0.1.44"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d2cc698a63b549a70bc047073d2949cce27cd1c7b0a4a862d08a8031bc2801db"
+dependencies = [
+ "autocfg",
+ "num-traits",
+]
+
+[[package]]
+name = "num-traits"
+version = "0.2.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9a64b1ec5cda2586e284722486d802acf1f7dbdc623e2bfc57e65ca1cd099290"
+dependencies = [
+ "autocfg",
+]
+
 [[package]]
 name = "once_cell"
 version = "1.8.0"
@@ -967,6 +1000,17 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "time"
+version = "0.1.44"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6db9e6914ab8b1ae1c260a4ae7a49b6c5611b40328a735b21862567685e73255"
+dependencies = [
+ "libc",
+ "wasi",
+ "winapi",
+]
+
 [[package]]
 name = "toml"
 version = "0.5.8"
@@ -1018,6 +1062,12 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9d5b2c62b4012a3e1eca5a7e077d13b3bf498c4073e33ccd58626607748ceeca"
 
+[[package]]
+name = "wasi"
+version = "0.10.0+wasi-snapshot-preview1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1a143597ca7c7793eff794def352d41792a93c481eb1042423ff7ff72ba2c31f"
+
 [[package]]
 name = "wepoll-ffi"
 version = "0.1.2"

Cargo.toml

@@ -5,6 +5,7 @@ edition = "2018"
 
 [dependencies]
 cascade = "1"
+chrono = "0.4"
 gdk4-x11 = "0.2"
 gtk4 = "0.2"
 toml = "0.5"

src/main.rs

@@ -5,6 +5,8 @@ mod x;
 
 fn main() {
     gtk4::init().unwrap();
+    let main_context = glib::MainContext::default();
+    let _acquire_guard = main_context.acquire().unwrap();
 
     let display = gdk::Display::default().unwrap();
     let monitors = display.monitors().unwrap();

src/window.rs

@@ -5,6 +5,16 @@ use gtk4::{gdk, glib, prelude::*};
 use crate::x;
 
 pub fn window(monitor: gdk::Monitor) -> gtk4::Window {
+    let time_button = cascade! {
+        gtk4::MenuButton::new();
+        ..set_popover(Some(&cascade! {
+            gtk4::Popover::new();
+            ..set_child(Some(&cascade! {
+                gtk4::Calendar::new();
+            }));
+        }));
+    };
+
     let box_ = cascade! {
         gtk4::CenterBox::new();
         ..set_start_widget(Some(&cascade! {
@@ -12,16 +22,7 @@ pub fn window(monitor: gdk::Monitor) -> gtk4::Window {
             ..append(&gtk4::Button::with_label("Workspaces"));
             ..append(&gtk4::Button::with_label("Applications"));
         }));
-        ..set_center_widget(Some(&cascade! {
-            gtk4::MenuButton::new();
-            ..set_label("Jan 1 00:00 AM");
-            ..set_popover(Some(&cascade! {
-                gtk4::Popover::new();
-                ..set_child(Some(&cascade! {
-                    gtk4::Calendar::new();
-                }));
-            }));
-        }));
+        ..set_center_widget(Some(&time_button));
     };
 
     let window = cascade! {
@@ -31,6 +32,23 @@ pub fn window(monitor: gdk::Monitor) -> gtk4::Window {
         ..show();
     };
 
+    fn update_time(time_button: &gtk4::MenuButton) {
+        // TODO: Locale-based formatting?
+        let time = chrono::Local::now();
+        time_button.set_label(&time.format("%b %-d %-I:%M %p").to_string());
+        // time.format("%B %-d %Y")
+    }
+
+    // TODO: better way to do this?
+    glib::timeout_add_seconds_local(
+        1,
+        clone!(@weak time_button => @default-return glib::Continue(false), move || {
+            update_time(&time_button);
+            glib::Continue(true)
+        }),
+    );
+    update_time(&time_button);
+
     fn monitor_geometry_changed(window: &gtk4::Window, monitor: &gdk::Monitor) {
         let geometry = monitor.geometry();
         window.set_size_request(geometry.width, 0);