Vuejs 3.3 defineModel always returns undefined what is the problem? – Javascript

The Solutions:

Solution 1: Disable conflicting Nuxt hook

The issue was caused by a conflicting Nuxt hook. The vite:extendConfig hook was overriding the Vue configuration set in the vite section of nuxt.config.ts. To resolve the issue, disable the vite:extendConfig hook, and the defineModel macro will start working as expected:

// Disable the conflicting hook
hooks: {
  // Remove the "vite:extendConfig" hook
},
// Keep the vite section for Vue configuration
vite:{      
  vue: {
    script: {
      defineModel: true,
      propsDestructure: true                 
    }
  }
}

Solution 2: Use the defineModel Macro Correctly

The defineModel macro automatically handles prop registration and returns a ref that can be directly mutated. Ensure you use the macro correctly by following these steps:

• Import the defineModel macro: import { defineModel } from 'vue';
• Use the macro to define the model: const count = defineModel();

Note that the defineModel macro does not return the value of the model initially. To access the value, use .value after the model has been initialized: console.log(count.value);

Additionally, you can use the watch function to track changes in the model’s value and perform necessary updates:

watch(
  () => count.value,
  (n) => {
    console.log(n);
  }
);

Video Explanation:

The following video, titled "3 Ways to Persist Pinia State - YouTube", provides additional insights and in-depth exploration related to the topics discussed in this post.

... vuejs/pinia/issues/309 https://github.com/prazdevs/pinia-plugin-persistedstate ✓ FREE VUE 3 CHEATSHEET WITH ESSENTIAL CODE SNIPPETS https ...