title: vuejs Computed data detecting if model has been updated
body: <p>I'm trying to detect if a Model Data has not been changed within a Vue Computed data.</p>
  
  <p>I have two sets of Variables that need to be checked,
  before Computed:filteredItems should return a new list or current list.</p>
  
  <p>Below are two data i'm checking</p>
  
  <ul>
  <li>text ( the text input )</li>
  <li>selectedInput ( currently selected item )</li>
  </ul>
  
  <p><strong>Current Behavior:</strong></p>
  
  <p>I've changed, <strong>selectedInput</strong> to null, this updates Computed:filteredList to be triggered. which is expected.</p>
  
  <p>The first Condition is to make sure that this update returns current list if <strong>text === selectedInput.text</strong>, work as expected</p>
  
  <p>However, I need a second condition to detect if <strong>text</strong> has not been changed.</p>
  
  <pre><code>&lt;input v-model="text" /&gt;
  &lt;ul&gt;
     &lt;li v-for="item in filteredItems" @click="text=item.text"&gt;&lt;/li&gt;
  &lt;/ul&gt;
  
  {
    data():{
       text: 1,
       items: [],
       tempList: [],
       selectedItem: {text: 1}
    },
    computed: {
       filteredItems(){
          // when selectedItem.text === current text input, do not run
          if (this.selectedItem.text === text) return this.tempList;
  
          // how do i detect if selectedItem.text has not been changed
          if (this.selectedItem.text.hasNotChange??) return this.tempList;
       }
    }
  }
  </code></pre>
  
  <p>Data Flow: 1update the text > 2filter list > 3click on listItem, update (1) text</p>
  
  <ol>
  <li>[input(text): update on type ] > </li>
  <li>[li(filteredItem): filter list on type by value (text) and (selectedInput.text) ] ></li>
  <li>[li(item)@click: update (1), and also another value(selectedInput.text) input(text) to equal (item.text) ]</li>
  </ol>
  
  <p>This cycle works until I have action somewhere else that updates selectedInput.text</p>
  
  <p>is there something i can do with a setter/getter for the <strong>Text</strong> model.</p>