added simple factory

src/factories/container_list.rs

@@ -0,0 +1,64 @@
+use crate::app::AppMsg;
+use gtk::prelude::{BoxExt, ButtonExt, GtkWindowExt, OrientableExt};
+use relm4::factory::{DynamicIndex, FactoryComponent, FactorySender, FactoryVecDeque};
+use relm4::{gtk, ComponentParts, ComponentSender, RelmApp, RelmWidgetExt, SimpleComponent};
+
+#[derive(Debug)]
+pub struct Container {
+    value: u8,
+}
+
+#[derive(Debug)]
+pub enum ContainerMsg {
+    Start,
+}
+
+#[relm4::factory(pub)]
+impl FactoryComponent for Container {
+    type Init = u8;
+    type Input = ContainerMsg;
+    type Output = ();
+    type CommandOutput = ();
+    type Widgets = ContainerWidgets;
+    type ParentInput = AppMsg;
+    type ParentWidget = gtk::Box;
+
+    view! {
+        root = gtk::Box {
+            set_orientation: gtk::Orientation::Horizontal,
+            set_spacing: 10,
+
+            #[name(label)]
+            gtk::Label {
+                #[watch]
+                set_label: &self.value.to_string(),
+                set_width_chars: 3,
+            },
+
+            #[name(add_button)]
+            gtk::Button {
+                set_label: "+",
+                connect_clicked => ContainerMsg::Start,
+            },
+
+            #[name(remove_button)]
+            gtk::Button {
+                set_label: "-",
+                connect_clicked => ContainerMsg::Start,
+            },
+        }
+    }
+
+    fn init_model(value: Self::Init, _index: &DynamicIndex, _sender: FactorySender<Self>) -> Self {
+        Self { value }
+    }
+
+    fn update(&mut self, msg: Self::Input, _sender: FactorySender<Self>) {
+        match msg {
+            ContainerMsg::Start => {
+                self.value = self.value.wrapping_add(1);
+            }
+        }
+    }
+}
+