Maybe it render, that took xxMS. What happen? Anytime I close the print page, I receive this message in the chrome console. Does anyone fix this problem?

<button @click="printScreen()" type="button">print</button>

<div ref="printparts">test</div>

    methods: {
          printScreen() {
            let value = this.$refs.printparts;
            let printPage = window.open();
            printPage.focus();
            printPage.document.body.insertAdjacentHTML('afterbegin', value.outerHTML);
            printPage.print();
            printPage.close();
          },
        },

Maybe it render, that took xxMS. What happen? Anytime I close the print page, I receive this message in the chrome console. Does anyone fix this problem?

<button @click="printScreen()" type="button">print</button>

<div ref="printparts">test</div>

    methods: {
          printScreen() {
            let value = this.$refs.printparts;
            let printPage = window.open();
            printPage.focus();
            printPage.document.body.insertAdjacentHTML('afterbegin', value.outerHTML);
            printPage.print();
            printPage.close();
          },
        },

• javascript
• vue.js
• render

• Can you also please show us the code for the button and for the event listener? – Sydney Y Commented Mar 1, 2020 at 4:32
• Sorry, I have edit my question, please review on it. Thanks – Tom Commented Mar 1, 2020 at 4:50

2 Answers 2

The reason why you are getting this violation warning is likely because the event handler doesn't return until the print page is closed. So, when you click the button the print page opens, then nothing happens until the print page is closed, then the function returns.

I used onmouseover and Chrome doesn't show the violation, but Performance say Warning.

printScreen() {
        let value = this.$refs.printparts;
        let printPage = window.open();
        printPage.focus();
        printPage.document.body.insertAdjacentHTML('afterbegin', value.outerHTML);
        printPage.onmouseover = function() {
          printPage.print();
          printPage.close();
        };
        return false;
      },