sap.ui.core.HTML binding content issue

OpenUI5 version: 1.52.5

Browser/version (+device/version): Chrome

Any other tested browsers/devices(OK/FAIL): No

URL (minimal example if possible): https://ui5issues-a854a7813.dispatcher.hana.ondemand.com/index.html?hc_reset#/objectpagelayout

Steps to reproduce the problem: If i am binding the html markup using

<core:HTML content="{ui>/html}" sanitizeContent="true"/>

after changing the value, the bound html will be appended instead of replaced.

You can reporduce this in my example by triggering the section action “setHTML” which does

this._oViewModel.setProperty("/html", this._sHTML + "<b>" + Date.now() + "</b>");

What is the expected result? html code will be replaced

What happens instead? html code will be appended. The same line will be shown multiple times (to recognize this, i added Date.now() to the output).

Regards Holger

[codeworrior]

When you increase the log level so that UI5 also logs warnings, you’ll notice that the HTML control complains about the content that it receives:

[Unsupported Feature]: Element sap.ui.core.HTML#__html0 has rendered 5 root nodes!

If multiple root elements are given, the UI5 re-rendering doesn’t work. The HTML control only issues a warning in this case as in the past we had some use cases that didn’t require re-rendering.

Nevertheless, I wondered about the number of 5 root nodes. This seems to be caused by the content string:

<p><h2>This is my headline...</h2><br/>text</p>

According to the HTML5 spec, the content model for <p> is phrasing content, but <h2> is no phrasing content. Furthermore, the spec allows to omit the closing </p> when e.g. <h2> tag follows. So the browser parses the string automatically as

<p></p> <h2>This is my headline...</h2> <br> text <p></p>

which indeed gives 5 root nodes (one of them a text node).

When I change the wrapper to a <div> instead of <p>and pay attention that setHtml also creates the same (and does not append another root node <b>), then it works as expected.

[codeworrior]

That’s what I meant with my last comment:

Adding such a wrapper automatically would be worth another property in the HTML control, I guess.

For compatibility reasons, we can’t always add a wrapper.