Check out example codes for "$emit in vue". It will help you in understanding the concepts better.

Code Example 1

<!--
VERY Simplified example
Our parent comp reference child comp
-->
<parent-comp>
  <template>
  	<!-- Remember to add the callback to the child comp -->
  	<child-comp
		@askParentToDoStuff="doStuff">
    </child-comp>
  </template>
  <script>
	methods() {
  	  function doStuff(param) {
        console.log('received: ', param);
        // logs: received: 'foo'
      }
	}
  </script>
</parent-comp>

<!-- Child comp -->
<child-comp>
  <template>
    <p>Im the child comp</p>
    <button :click="myFunction('foo')">Click Me</button>
  </template>
  <script>
  	methods() {
  	  function myFunction(param) {
        // See the callback in the child comp reference
        // in the parent comp
        this.$emit('askParentToDoStuff', param);
      }
	}
  </script>
</child-comp>

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