現在我們新增一個todo的檔案todo.rs

use rusqlite::{Connection, Result};
use serde::{Serialize, Deserialize};

#[derive(Serialize, Deserialize)]
pub struct Todo {
  pub id: String,
  pub title: String,
  pub date: String,
  pub done: bool,
}

pub struct TodoApp {
  pub conn: Connection,
}

impl TodoApp {
  pub fn new()->Result<TodoApp>{
    let db_path = "db.sqlite";
    let conn = Connection::open(db_path)?;
    conn.execute(
        "CREATE TABLE IF NOT EXISTS Todo (
            id          varchar(64)     PRIMARY KEY,
            title       text            NOT NULL,
            date        text            NOT NULL,
            done        numeric         DEFAULT 0
        )",
        [],
    )?;
    Ok(TodoApp { conn })
  }
  
}

到main.rs新增:

mod todo;
use todo::{Todo, TodoApp};

並加入new方法到main()裡

fn main() {
  let app = TodoApp::new().unwrap();

此時，我們測試一下
pnpm tauri dev
我們發現出現warning，但我們能看到main.rs創建了db.sqlite

接著，我們打開並能看到table建起來了

接著回到todo.rs，新增獲取所有todo功能

impl TodoApp {
  ...

  // Get All
  pub fn get_todos(&self) -> Result<Vec<Todo>> {
    let mut stmt = self.conn.prepare("SELECT * FROM Todo").unwrap();
    let todos_iter = stmt.query_map([], |row| {
        let done = row.get::<usize, i32>(3).unwrap() == 1;

        Ok(Todo {
            id: row.get(0)?,
            title: row.get(1)?,
            date: row.get(2)?,
            done,
        })
    })?;
    let mut todos: Vec<Todo> = Vec::new();

    for todo in todos_iter {
        todos.push(todo?);
    }

    Ok(todos)
  }
}

回到main.rs，接著將這個方法給加入到我們tauri中

...
use std::sync::Mutex;
use tauri::{CustomMenuItem, Menu, MenuItem, Submenu, Manager};

mod todo;
use todo::{Todo, TodoApp};

struct AppState {
    app: Mutex<TodoApp>,
}

fn main() {
    tauri::Builder::default()
	
	      ...
	
	   		.invoke_handler(tauri::generate_handler![
				  get_todos,
				])
				.manage(AppState {
					app: Mutex::from(app),
				})
		
		...
}

#[tauri::command]
fn get_todos(state: tauri::State<AppState>) -> Vec<Todo> {
    let app = state.app.lock().unwrap();
    let todos = app.get_todos().unwrap();
    todos
}

此時，我們能獲取所有todo的item了

測試方法，我們嘗試透過WebView Console

透過設置todo\src-tauri\tauri.conf.json裡面的tauri.conf.json > build > withGlobalTauri為true來將調用掛載到window.__TAURI__對像上

打開我們的App，並按下F12，叫出devTool。並在我們的console輸入await __TAURI__.invoke("get_todos")測試

我們發現能調用get_todos的方法了。明天接著把CRUD的功能給完善