Category: vue2

Vue composition API tutorial with example

In this, I’ll show you how to vue2 composition API.

Let us do a small example todo app with Vue composition API
Vue 3 come up with Composition API, in Vue 2, we use The Options API, where we use uses options like datamethods, and mounted. With the Composition API, we have a setup hook in which we write our reactive code and functions.
We can re-use the same functions in between components using Composition API, and save a lot of time.

Demo: https://vue-composition-api-simple-todo.pages.dev/

Setup and Installation

We can install vueCLI and create a new project using vue create vue-composition-api-simple-todo. Please refer to my previous post in case you missed it.
Once we create our Vue project open the code base and let’s start with installing @vue/composition-api

Install dependencies

 npm i  @vue/composition-api --save

Let us take the same HTML from my last past, simple vue todo app Here you can read it if you miss

Let us import @vue/composition-api and use it main.js

import CompositionApi from '@vue/composition-api'
Vue.use(CompositionApi)

Start with coding

Full code of main.js looks like below

import Vue from 'vue'
import App from './App.vue'
import CompositionApi from '@vue/composition-api'

Vue.config.productionTip = false
Vue.use(CompositionApi)

new Vue({
  render: h => h(App),
}).$mount('#app')

Let us create a new folder for composable functions

We can define Todos list in composable function like below

import { reactive } from "@vue/composition-api";
function useTodoList() {
  let state = reactive({
    newTodo: "",
    todos: [
      {
        id: 1,
        title: "Buy groceries for next week",
        completed: false,
      },
      {
        id: 2,
        title: "Pay credit card bill ",
        completed: false,
      },
    ],
  });

  return {
    state, 
  };
}

export default useTodoList

We use the same date, in composition functions, we will define state using Reactivity API, e.g. ref() and reactive(), that allows us to directly create reactive state, computed state, and watchers.
In this example, we use reactive to define the state and now we can use todos inside out template.

in components/TodoList.vue we can import composable function

import useTodoList from "@/composable/useTodoList";
export default {
  setup() {
    const { state} = useTodoList();
    return {
      state,
    };
  },
};

and we can use it in the template

<tbody>
                    <tr
                      v-for="(todo, idx) in state.todos"
                      :key="todo.id"
                      :class="todo.completed && 'stricked'"
                    >
                      <th scope="row">{{ idx + 1 }}</th>
                      .....
                    </tr>
                  </tbody>

Start the app

If we run the application we can see a list of todos 🙂

Let’s add more functionality like addtodo toggleCompleted and removeItem in composable/useTodoList.js.
The final code looks like below

import { reactive } from "@vue/composition-api";
function useTodoList() {
 ......

  function addToDo(e) {
    console.log("state.newTodo", state, state.newTodo);
    e.preventDefault();
    state.todos.push({
      id: state.todos.length + 1,
      title: state.newTodo,
      completed: false,
    });
    state.newTodo = "";
  }

  function toggleCompleted(item) {
    item.completed = !item.completed;
  }
  function removeItem(item) {
    state.todos = state.todos.filter((newItem) => newItem.id !== item.id);
  }
  return {
    state,
    addToDo,
    toggleCompleted,
    removeItem,
  };
}

export default useTodoList

Let us import addtodo toggleCompleted and removeItem in components/TodoList.vue


<script>
import useTodoList from "@/composable/useTodoList";
export default {
  setup() {
    const { state, addToDo, toggleCompleted, removeItem } = useTodoList();
    return {
      state,
      addToDo,
      toggleCompleted,
      removeItem,
    };
  },
};
</script>

How we can use it in the template?

....
                  <div class="col-12">
                    <button
                      type="button"
                      class="btn btn-primary"
                      @click="addToDo"
                    >
                      Save
                    </button>
                  </div>

                  .......

                  <tbody>
                    <tr
                      v-for="(todo, idx) in state.todos"
                      :key="todo.id"
                      :class="todo.completed && 'stricked'"
                    >
                      <th scope="row">{{ idx + 1 }}</th>
                      <td>{{ todo.title }}</td>
                      <td>
                        {{ todo.completed ? "Completed" : "In progress" }}
                      </td>
                      <td>
                        <button
                          type="submit"
                          class="btn btn-danger"
                          @click="removeItem(todo)"
                        >
                          Delete
                        </button>
                        <button
                          type="submit"
                          class="btn btn-success ms-1"
                          @click="toggleCompleted(todo)"
                        >
                          {{ todo.completed ? "Re-open" : "Complete" }}
                        </button>
                      </td>
                    </tr>
                  </tbody>
             
             ....

Once we run the server, we can see add toggle and remove is working

vue composition api todo example

Getting everything working

components/TodoList.vue

<template>
  <div class="hello">
    <section class="vh-100" style="background-color: #eee">
      <div class="container py-5 h-100">
        <div class="row d-flex justify-content-center align-items-center h-100">
          <div class="col col-lg-9 col-xl-7">
            <div class="card rounded-3">
              <div class="card-body p-4">
                <h4 class="text-center my-3 pb-3">
                  Simple Vue 2 with composition-api To Do App
                </h4>

                <form
                  class="row row-cols-lg-auto g-3 justify-content-center align-items-center mb-4 pb-2"
                  @submit.prevent="addToDo"
                >
                  <div class="col-12">
                    <div class="form-outline">
                      <input
                        type="text"
                        id="form1"
                        v-model="state.newTodo"
                        class="form-control"
                        placeholder="Enter a task here"
                      />
                    </div>
                  </div>

                  <div class="col-12">
                    <button
                      type="button"
                      class="btn btn-primary"
                      @click="addToDo"
                    >
                      Save
                    </button>
                  </div>

                  <div class="col-12">
                    <button type="submit" class="btn btn-warning">
                      Get tasks
                    </button>
                  </div>
                </form>

                <table class="table mb-4">
                  <thead>
                    <tr>
                      <th scope="col">No.</th>
                      <th scope="col">Todo item</th>
                      <th scope="col">Status</th>
                      <th scope="col">Actions</th>
                    </tr>
                  </thead>

                  <tbody>
                    <tr
                      v-for="(todo, idx) in state.todos"
                      :key="todo.id"
                      :class="todo.completed && 'stricked'"
                    >
                      <th scope="row">{{ idx + 1 }}</th>
                      <td>{{ todo.title }}</td>
                      <td>
                        {{ todo.completed ? "Completed" : "In progress" }}
                      </td>
                      <td>
                        <button
                          type="submit"
                          class="btn btn-danger"
                          @click="removeItem(todo)"
                        >
                          Delete
                        </button>
                        <button
                          type="submit"
                          class="btn btn-success ms-1"
                          @click="toggleCompleted(todo)"
                        >
                          {{ todo.completed ? "Re-open" : "Complete" }}
                        </button>
                      </td>
                    </tr>
                  </tbody>
                </table>
              </div>
            </div>
          </div>
        </div>
      </div>
    </section>
  </div>
</template>

<script>
import useTodoList from "@/composable/useTodoList";
export default {
  setup() {
    const { state, addToDo, toggleCompleted, removeItem } = useTodoList();
    return {
      state,
      addToDo,
      toggleCompleted,
      removeItem,
    };
  },
};
</script>

<!-- Add "scoped" attribute to limit CSS to this component only -->
<style scoped>
h3 {
  margin: 40px 0 0;
}
ul {
  list-style-type: none;
  padding: 0;
}
li {
  display: inline-block;
  margin: 0 10px;
}
a {
  color: #37dd92;
}
.stricked {
  text-decoration: line-through;
}
</style>

composable/useTodoList.js

import { reactive } from "@vue/composition-api";
function useTodoList() {
  let state = reactive({
    newTodo: "",
    todos: [
      {
        id: 1,
        title: "Buy groceries for next week",
        completed: false,
      },
      {
        id: 2,
        title: "Pay credit card bill ",
        completed: false,
      },
    ],
  });

  function addToDo(e) {
    console.log("state.newTodo", state, state.newTodo);
    e.preventDefault();
    state.todos.push({
      id: state.todos.length + 1,
      title: state.newTodo,
      completed: false,
    });
    state.newTodo = "";
  }

  function toggleCompleted(item) {
    item.completed = !item.completed;
  }
  function removeItem(item) {
    state.todos = state.todos.filter((newItem) => newItem.id !== item.id);
  }
  return {
    state,
    addToDo,
    toggleCompleted,
    removeItem,
  };
}

export default useTodoList

That’s it Yey !!!

Repo: https://github.com/shabeeb/vue-composition-api-simple-todo

Demo: https://vue-composition-api-simple-todo.pages.dev/

Thank you for reading and Happy coding 🙂

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Simple Vue 2 Tutorial with Example app


Let’s make a simple vue project example with a TODO list

Setup and Installation

There are two ways to set up Vue: through a VueCLI, or by including a script inside of your HTML file. Let’s do with VueCLI, We can install vue vueCLI globally

npm install -g @vue/cli or yarn global add @vue/cli

Once install complete, let’s create a project by using the below comment

vue create vue-simple-todo

Lets select Vue 2 for this example

Lets select Vue 2 for this example and click enter

Then it will ask for package manager ( Here i am going with npm in this case)

Here is my final screenshot after completing project stup

Now as mentioned there we can cd into folder and start server

npm run serve

Now server will run on http://localhost:8080/. We can open a browser and see basic vue template in browser

deafault vue page

Now let’s take a look on codebase (I am using VS Code for editing files)

We can see App.vue and components folder below

Let’s start our coding 🙂

Let’s start with some cleanup, remove HelloWorld.vue from components, and create a new file TodoList.vue

Then we can import TodoList.vue inside App.vue

<template>
  <div id="app">
    <TodoList />
  </div>
</template>

<script>
import TodoList from "./components/TodoList.vue";

export default {
  name: "App",
  components: {
    TodoList,
  },
};
</script>

In TodoList.vue, We can start with the todo Skelton template, a very basic HTML todo Layout, and a simple vue class.

<template>
  <div class="hello">
    <section class="vh-100" style="background-color: #eee">
      <div class="container py-5 h-100">
        <div class="row d-flex justify-content-center align-items-center h-100">
          <div class="col col-lg-9 col-xl-7">
            <div class="card rounded-3">
              <div class="card-body p-4">
                <h4 class="text-center my-3 pb-3">Simple Vue To Do App</h4>

                <form
                  class="row row-cols-lg-auto g-3 justify-content-center align-items-center mb-4 pb-2"
                >
                  <div class="col-12">
                    <div class="form-outline">
                      <input type="text" id="form1" class="form-control"
placeholder="Enter a task here" />
                      
                    </div>
                  </div>

                  <div class="col-12">
                    <button type="submit" class="btn btn-primary">Save</button>
                  </div>

                  <div class="col-12">
                    <button type="submit" class="btn btn-warning">
                      Get tasks
                    </button>
                  </div>
                </form>

                <table class="table mb-4">
                  <thead>
                    <tr>
                      <th scope="col">No.</th>
                      <th scope="col">Todo item</th>
                      <th scope="col">Status</th>
                      <th scope="col">Actions</th>
                    </tr>
                  </thead>
                  <tbody>
                    <tr>
                      <th scope="row">1</th>
                      <td>Buy groceries for next week</td>
                      <td>In progress</td>
                      <td>
                        <button type="submit" class="btn btn-danger">
                          Delete
                        </button>
                        <button type="submit" class="btn btn-success ms-1">
                          Finished
                        </button>
                      </td>
                    </tr>
                    <tr>
                      <th scope="row">2</th>
                      <td>Renew car insurance</td>
                      <td>In progress</td>
                      <td>
                        <button type="submit" class="btn btn-danger">
                          Delete
                        </button>
                        <button type="submit" class="btn btn-success ms-1">
                          Complete
                        </button>
                      </td>
                    </tr>
                  </tbody>
                </table>
              </div>
            </div>
          </div>
        </div>
      </div>
    </section>
  </div>
</template>

<script>
export default {
  name: "TodoList",
};
</script>

<!-- Add "scoped" attribute to limit CSS to this component only -->
<style scoped>
h3 {
  margin: 40px 0 0;
}
ul {
  list-style-type: none;
  padding: 0;
}
li {
  display: inline-block;
  margin: 0 10px;
}
a {
  color: #37dd92;
}
.stricked {
  text-decoration: line-through;
}
</style>

To get bootstrap let’s add bootstrap CDN to index.html (Or we install and add in App.vue also)

<link
      href="https://cdn.jsdelivr.net/npm/bootstrap@5.1.3/dist/css/bootstrap.min.css"
      rel="stylesheet"
      integrity="sha384-1BmE4kWBq78iYhFldvKuhfTAU6auU8tT94WrHftjDbrCEXSU1oBoqyl2QvZ6jIW3"
      crossorigin="anonymous"
    />

Now We can define data inside vue class, and move HTML labels from template to todos variable inside data. Here we define our todo list variable and assign some values.

data() {
    return {
      todos: [
        {
          id: 1,
          title: "Buy groceries for next week",
          completed: false,
        },
        {
          id: 2,
          title: "Renew car insurance",
          completed: false,
        },
      ],
    };
  },

Let’s add some logic to template also,
Since we moved todos from HTML table to vue, we can use v-for to show data in HTML as shown below.

<table class="table mb-4">
                  <thead>
                    ......
                  </thead>
                  <tbody>
                    <tr v-for="(todo, idx) in todos" :key="todo.id">
                      <th scope="row">{{ idx + 1 }}</th>
                      <td>{{ todo.title }}</td>
                      <td>
                        {{ todo.completed ? "Completed" : "In progress" }}
                      </td>
                      <td>
                        <button type="submit" class="btn btn-danger">
                          Delete
                        </button>
                        <button type="submit" class="btn btn-success ms-1">
                          Complete
                        </button>
                      </td>
                    </tr>
                  </tbody>
                </table>

Now the out will show as below

Now let us add some logic to save functionality

Add v-modal for input button and define v-modal inside data()

<input
                        type="text"
                        id="form1"
                        v-model="newTodo"
                        class="form-control"
                        placeholder="Enter a task here"
                      />

......
data() {
    return {
      newTodo: "",
      todos: [
        {
          id: 1,
          title: "Buy groceries for next week",
          completed: false,
        },
        {
          id: 2,
          title: "Pay credit card bill ",
          completed: false,
        },
      ],
    };
  },

Let’s add the click functionality for the save button, We can add methods below data() add functionality as below.
Finally, we will clear newTodo once we added to the current list. On the template, we call this method on the save button as below

<template>
....
<button
                      type="button"
                      class="btn btn-primary"
                      @click="addToDo"
                    >
                      Save
                    </button>
</tempate>
<script>
data() {
.....
},
methods: {
    addToDo(e) {
      e.preventDefault();
      this.todos.push({
        id: this.todos.length + 1,
        title: this.newTodo,
        completed: false,
      });
      this.newTodo = "";
    },
    
  },
.....

Now run server and see in action, we can type todo and on click, it will come on below list.

let’s add remove functionality and toggle functionality. To add both

<template>
.....
<tbody>
                    <tr
                      v-for="(todo, idx) in todos"
                      :key="todo.id"
                      :class="todo.completed && 'stricked'"
                    >
                      <th scope="row">{{ idx + 1 }}</th>
                      <td>{{ todo.title }}</td>
                      <td>
                        {{ todo.completed ? "Completed" : "In progress" }}
                      </td>
                      <td>
                        <button
                          type="submit"
                          class="btn btn-danger"
                          @click="removeItem(todo)"
                        >
                          Delete
                        </button>
                        <button
                          type="submit"
                          class="btn btn-success ms-1"
                          @click="toggleCompleted(todo)"
                        >
                          {{ todo.completed ? "Re-open" : "Complete" }}
                        </button>
                      </td>
                    </tr>
                  </tbody>
.....
</template>
<script>
......

 methods: {
    addToDo(e) {
      e.preventDefault();
      this.todos.push({
        id: this.todos.length + 1,
        title: this.newTodo,
        completed: false,
      });
      this.newTodo = "";
    },
    toggleCompleted: function (item) {
      item.completed = !item.completed;
    },
    removeItem: function (item) {
      this.todos = this.todos.filter((newItem) => newItem.id !== item.id);
    },
  },
......

This is a simple TODO app using vue2.
Please check out GitHub for the full codebase. https://github.com/shabeeb/vue2-todo

Demo: https://vue2-todo.pages.dev/
Thank you for reading.
please comment

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