Improvments to launcher.

Moved UI building to a function.
Found a way to clear GtkListBox without a loop.
Ran rustfmt.

.gitignore

@@ -1,2 +1,3 @@
 /target
 Cargo.lock
+.idea

examples/launcher/ipc.rs

@@ -1,6 +1,6 @@
 use pop_launcher::{Request, Response};
-use std::process;
 use std::io::{self, BufRead, Write};
+use std::process;
 
 pub struct LauncherIpc {
     child: process::Child,
@@ -16,13 +16,15 @@ impl LauncherIpc {
             .stdout(process::Stdio::piped())
             .spawn()?;
 
-        let stdin = child.stdin.take().ok_or(
+        let stdin = child.stdin.take().ok_or(io::Error::new(
-            io::Error::new(io::ErrorKind::Other, "failed to find child stdin")
+            io::ErrorKind::Other,
-        )?;
+            "failed to find child stdin",
+        ))?;
 
-        let stdout = io::BufReader::new(child.stdout.take().ok_or(
+        let stdout = io::BufReader::new(child.stdout.take().ok_or(io::Error::new(
-                io::Error::new(io::ErrorKind::Other, "failed to find child stdout")
+            io::ErrorKind::Other,
-        )?);
+            "failed to find child stdout",
+        ))?);
 
         Ok(Self {
             child,
@@ -33,9 +35,8 @@ impl LauncherIpc {
     }
 
     fn send_request(&mut self, request: Request) -> io::Result<()> {
-        let mut request_json = serde_json::to_string(&request).map_err(|err| {
+        let mut request_json = serde_json::to_string(&request)
-            io::Error::new(io::ErrorKind::InvalidInput, err)
+            .map_err(|err| io::Error::new(io::ErrorKind::InvalidInput, err))?;
-        })?;
         request_json.push('\n');
         self.stdin.write_all(request_json.as_bytes())
     }
@@ -43,9 +44,8 @@ impl LauncherIpc {
     fn recv_response(&mut self) -> io::Result<Response> {
         let mut response_json = String::new();
         self.stdout.read_line(&mut response_json)?;
-        serde_json::from_str(&response_json).map_err(|err| {
+        serde_json::from_str(&response_json)
-            io::Error::new(io::ErrorKind::InvalidData, err)
+            .map_err(|err| io::Error::new(io::ErrorKind::InvalidData, err))
-        })
     }
 
     pub fn request(&mut self, request: Request) -> io::Result<Response> {
@@ -55,7 +55,7 @@ impl LauncherIpc {
 
     //TODO: better exit implementation
     pub fn exit(&mut self) -> io::Result<Option<process::ExitStatus>> {
-        if ! self.exited {
+        if !self.exited {
             self.send_request(Request::Exit)?;
             let status = self.child.wait()?;
             self.exited = true;

examples/launcher/main.rs

@@ -1,11 +1,10 @@
 use gtk4 as gtk;
 
 use gtk::prelude::*;
+use gtk4::Application;
 use libcosmic::x;
-use std::{
+use std::{cell::RefCell, rc::Rc};
-    cell::RefCell,
+use gtk4::glib::Type;
-    rc::Rc,
-};
 
 use self::ipc::LauncherIpc;
 mod ipc;
@@ -14,12 +13,10 @@ fn icon_source(icon: &gtk::Image, source: &Option<pop_launcher::IconSource>) {
     match source {
         Some(pop_launcher::IconSource::Name(name)) => {
             icon.set_from_icon_name(Some(name));
-        },
+        }
         Some(pop_launcher::IconSource::Mime(content_type)) => {
-            icon.set_from_gicon(
+            icon.set_from_gicon(&gio::content_type_get_icon(content_type));
-                &gio::content_type_get_icon(content_type)
+        }
-            );
-        },
         _ => {
             icon.set_from_icon_name(None);
         }
@@ -27,120 +24,123 @@ fn icon_source(icon: &gtk::Image, source: &Option<pop_launcher::IconSource>) {
 }
 
 fn main() {
-    let launcher = Rc::new(RefCell::new(
-        LauncherIpc::new().expect("failed to connect to launcher service")
-    ));
-
     let app = gtk::Application::builder()
         .application_id("com.system76.Launcher")
         .build();
 
-    app.connect_activate(move |app| {
+    app.connect_activate(move |app| build_ui(app));
-        let window = gtk::ApplicationWindow::builder()
-            .application(app)
-            .decorated(false)
-            .default_width(480)
-            .default_height(440)
-            .title("Launcher")
-            .build();
-
-        let vbox = gtk::Box::new(gtk::Orientation::Vertical, 16);
-        vbox.set_margin_start(16);
-        vbox.set_margin_end(16);
-        vbox.set_margin_top(16);
-        vbox.set_margin_bottom(16);
-        window.set_child(Some(&vbox));
-
-        let search = gtk::SearchEntry::new();
-        search.set_placeholder_text(Some(" Type to search apps, or type '?' for more options."));
-        vbox.append(&search);
-
-        let listbox = gtk::ListBox::new();
-        vbox.append(&listbox);
-
-        {
-            let launcher = launcher.clone();
-            let search_changed = move |search: &gtk::SearchEntry| {
-                //TODO: is this the best way to clear a listbox?
-                while let Some(child) = listbox.last_child() {
-                    listbox.remove(&child);
-                }
-
-                let response_res = launcher.borrow_mut().request(
-                    pop_launcher::Request::Search(search.text().to_string())
-                );
-
-                println!("{:#?}", response_res);
-
-                if let Ok(pop_launcher::Response::Update(results)) = response_res {
-                    for (i, result) in results.iter().enumerate() {
-                        // Limit to 9 results
-                        if i >= 9 { continue; }
-
-                        let row = gtk::ListBoxRow::new();
-                        listbox.append(&row);
-
-                        // Select first row
-                        if i == 0 {
-                            listbox.select_row(Some(&row));
-                        }
-
-                        let hbox = gtk::Box::new(gtk::Orientation::Horizontal, 8);
-                        hbox.set_margin_start(8);
-                        hbox.set_margin_end(8);
-                        hbox.set_margin_top(8);
-                        hbox.set_margin_bottom(8);
-                        row.set_child(Some(&hbox));
-
-                        let category_icon = gtk::Image::new();
-                        category_icon.set_pixel_size(16);
-                        icon_source(&category_icon, &result.category_icon);
-                        hbox.append(&category_icon);
-
-                        let icon = gtk::Image::new();
-                        icon.set_pixel_size(32);
-                        icon_source(&icon, &result.icon);
-                        hbox.append(&icon);
-
-                        let labels = gtk::Box::new(gtk::Orientation::Vertical, 4);
-                        hbox.append(&labels);
-
-                        let name = gtk::Label::new(Some(&result.name));
-                        name.set_halign(gtk::Align::Start);
-                        labels.append(&name);
-
-                        let description = gtk::Label::new(Some(&result.description));
-                        description.set_halign(gtk::Align::Start);
-                        labels.append(&description);
-                    }
-                }
-            };
-
-            search.connect_changed(search_changed.clone());
-
-            search_changed(&search);
-        }
-
-        // Setting the window to dialog type must happen between realize and show. Dialog windows
-        // show up centered on the display with the cursor, so we do not have to set position
-        window.connect_realize(move |window| {
-            if let Some((display, surface)) = x::get_window_x11(window) {
-                unsafe {
-                    x::change_property(
-                        &display,
-                        &surface,
-                        "_NET_WM_WINDOW_TYPE",
-                        x::PropMode::Replace,
-                        &[x::Atom::new(&display, "_NET_WM_WINDOW_TYPE_DIALOG").unwrap()],
-                    );
-                }
-            } else {
-                println!("failed to get X11 window");
-            }
-        });
-
-        window.show();
-    });
 
     app.run();
 }
+
+fn build_ui(app: &Application) {
+    let launcher = Rc::new(RefCell::new(
+        LauncherIpc::new().expect("failed to connect to launcher service"),
+    ));
+
+    let window = gtk::ApplicationWindow::builder()
+        .application(app)
+        .decorated(false)
+        .default_width(590)
+        .default_height(150)
+        .title("Launcher")
+        .build();
+
+    let vbox = gtk::Box::new(gtk::Orientation::Vertical, 16);
+    vbox.set_margin_start(16);
+    vbox.set_margin_end(16);
+    vbox.set_margin_top(16);
+    vbox.set_margin_bottom(16);
+    window.set_child(Some(&vbox));
+
+    let search = gtk::SearchEntry::new();
+    search.set_placeholder_text(Some(" Type to search apps, or type '?' for more options."));
+    vbox.append(&search);
+    {
+        let launcher = launcher.clone();
+        let search_changed = move |search: &gtk::SearchEntry| {
+            let listbox_widget = vbox.last_child().unwrap();
+            let gtk_list_box = Type::from_name("GtkListBox");
+            if gtk_list_box.is_some() && listbox_widget.type_() == gtk_list_box.unwrap() {
+                vbox.remove(&listbox_widget);
+            }
+            let listbox = gtk::ListBox::new();
+            vbox.append(&listbox);
+
+            let response_res = launcher
+                .borrow_mut()
+                .request(pop_launcher::Request::Search(search.text().to_string()));
+
+            // println!("{:#?}", response_res);
+
+            if let Ok(pop_launcher::Response::Update(results)) = response_res {
+                for (i, result) in results.iter().enumerate() {
+                    // Limit to 9 results
+                    if i >= 9 {
+                        continue;
+                    }
+
+                    let row = gtk::ListBoxRow::new();
+                    listbox.append(&row);
+
+                    // Select first row
+                    if i == 0 {
+                        listbox.select_row(Some(&row));
+                    }
+
+                    let hbox = gtk::Box::new(gtk::Orientation::Horizontal, 8);
+                    hbox.set_margin_start(8);
+                    hbox.set_margin_end(8);
+                    hbox.set_margin_top(8);
+                    hbox.set_margin_bottom(8);
+                    row.set_child(Some(&hbox));
+
+                    let category_icon = gtk::Image::new();
+                    category_icon.set_pixel_size(16);
+                    icon_source(&category_icon, &result.category_icon);
+                    hbox.append(&category_icon);
+
+                    let icon = gtk::Image::new();
+                    icon.set_pixel_size(32);
+                    icon_source(&icon, &result.icon);
+                    hbox.append(&icon);
+
+                    let labels = gtk::Box::new(gtk::Orientation::Vertical, 4);
+                    hbox.append(&labels);
+
+                    let name = gtk::Label::new(Some(&result.name));
+                    name.set_halign(gtk::Align::Start);
+                    labels.append(&name);
+
+                    let description = gtk::Label::new(Some(&result.description));
+                    description.set_halign(gtk::Align::Start);
+                    labels.append(&description);
+                }
+            }
+        };
+
+        search.connect_changed(search_changed.clone());
+
+        search_changed(&search);
+    }
+
+    // Setting the window to dialog type must happen between realize and show. Dialog windows
+    // show up centered on the display with the cursor, so we do not have to set position
+    window.connect_realize(move |window| {
+        if let Some((display, surface)) = x::get_window_x11(window) {
+            unsafe {
+                x::change_property(
+                    &display,
+                    &surface,
+                    "_NET_WM_WINDOW_TYPE",
+                    x::PropMode::Replace,
+                    &[x::Atom::new(&display, "_NET_WM_WINDOW_TYPE_DIALOG").unwrap()],
+                );
+            }
+        } else {
+            println!("failed to get X11 window");
+        }
+    });
+
+    window.show();
+}