advotracker: reorganize the project using a crate based structure

* advotracker: the framework project
* crate/advotrackerdb: implementation of the database backend
* crate/advotrackerd: implementation of the backend (daemon)
* crate/adovtracker: implementaton of the application (CLI and GUI)

Signed-off-by: Ralf Zerres <ralf.zerres@networkx.de>

crates/advotracker_client/examples/messages_test/sender/sender_state.rs

@@ -0,0 +1,58 @@
+/*
+ * OrbTK - The Orbital Widget Toolkit
+ *
+ * Copyright 2021 Ralf Zerres <ralf.zerres@networkx.de>
+ * SPDX-License-Identifier: (0BSD or MIT)
+ */
+
+use orbtk::prelude::*;
+
+/// Enumeration of valid `action variants` that need to be handled as
+/// state changes for the `SenderView` widget.
+#[derive(Clone, Debug)]
+pub enum SenderAction {
+    UpdateProgress(f64),
+}
+
+/// Valid `structure members` of the `SenderState` used to react on
+/// state changes inside the `SenderView` widget.
+#[derive(AsAny, Default)]
+pub struct SenderState {
+    // actions
+    actions: Vec<SenderAction>,
+    // entity that will receive the message
+    target: Entity
+}
+
+/// Method definitions, we provide inside the `SenderState`.
+impl SenderState {
+    /// Sending message 'UpdateProgress'
+    pub fn send_message(&mut self) {
+        println!("Sender: push 'UpdateProgress' action");
+        self.actions.push(SenderAction::UpdateProgress(0.1));
+    }
+}
+
+/// Trait methods provided for the `SenderState`
+impl State for SenderState {
+    // initialize the view entities
+    fn init(&mut self, _registry: &mut Registry, ctx: &mut Context) {
+        // create the target entity, that receives the Sender messages
+        self.target = Entity::from(ctx.widget().try_clone::<u32>("target")
+            .expect("ERROR: SenderState::init(): target entity not found!"));
+    }
+
+    // update entities, before we render the view
+    fn update(&mut self, _: &mut Registry, ctx: &mut Context) {
+        let actions: Vec<SenderAction> = self.actions.drain(..).collect();
+
+        for action in actions {
+            match action {
+                SenderAction::UpdateProgress(amount) => {
+                    ctx.send_message(SenderAction::UpdateProgress(amount), self.target);
+                    println!("Sender: send message 'SenderAction::UpdateProgress'");
+                }
+            }
+        }
+    }
+}