Add announce Plugin

[BryanValverdeU]

• Add announce plugin
• Add a AnnounceHandler, that will be in charge of announcing the messages by using a aria-live element, this handler will require a string map with the localized strings to announce messages from built-in RoosterJS features.
• Add an additional callback property to ContentEditEventData, getAnnounceData, used in the Announce Plugin
• Add first announcing logic when indenting/outdenting list

[JiuqingSong]

In general, I'd like to discuss about the design.

Announcing is not a core function of editor, but should only be applied when A11y is cared. So can we make it as a plugin instead? And editor/other plugins just provides as few info as possible (I think your code already did this part).

For example, with ContentChangedEvent, we an add something about announcing, then the plugin see the event and see there is announcing info, then it will announce.

So if there is not such plugin added, we don't announce at all.

What do you thing? I'm open to disucss.

[BryanValverdeU]

In general, I'd like to discuss about the design.

Announcing is not a core function of editor, but should only be applied when A11y is cared. So can we make it as a plugin instead? And editor/other plugins just provides as few info as possible (I think your code already did this part).

For example, with ContentChangedEvent, we an add something about announcing, then the plugin see the event and see there is announcing info, then it will announce.

So if there is not such plugin added, we don't announce at all.

What do you thing? I'm open to disucss.

Thanks for checking Jason,

I agree with all you said.
Adding the additional announce info to the content changed event may need some specific plugin array ordering, which I think may be confusing to be used.
Because if there is a plugin that wanted us to announce something and it is after the new plugin, it may be missed.

Maybe we can just add a new PluginEvent for announcing and let the new plugin handle it exclussively. Do you think this could be a good way?

[JiuqingSong]

In general, I'd like to discuss about the design.
Announcing is not a core function of editor, but should only be applied when A11y is cared. So can we make it as a plugin instead? And editor/other plugins just provides as few info as possible (I think your code already did this part).
For example, with ContentChangedEvent, we an add something about announcing, then the plugin see the event and see there is announcing info, then it will announce.
So if there is not such plugin added, we don't announce at all.
What do you thing? I'm open to disucss.

Thanks for checking Jason,

I agree with all you said. Adding the additional announce info to the content changed event may need some specific plugin array ordering, which I think may be confusing to be used. Because if there is a plugin that wanted us to announce something and it is after the new plugin, it may be missed.

Maybe we can just add a new PluginEvent for announcing and let the new plugin handle it exclussively. Do you think this could be a good way?

I'm ok to have a new event type. But I also feel ContentChangedEvent should be fine, think about this:

• AnnouncePlugin
• SomeOtherPlugin

When SomeOtherPlugin trigger a ContentChangedEvent, it is a new event so that AnnouncePlugin will get it, it doesn't matter where SomeOtherPlugin is.

[BryanValverdeU]

In general, I'd like to discuss about the design.
Announcing is not a core function of editor, but should only be applied when A11y is cared. So can we make it as a plugin instead? And editor/other plugins just provides as few info as possible (I think your code already did this part).
For example, with ContentChangedEvent, we an add something about announcing, then the plugin see the event and see there is announcing info, then it will announce.
So if there is not such plugin added, we don't announce at all.
What do you thing? I'm open to disucss.

Thanks for checking Jason,
I agree with all you said. Adding the additional announce info to the content changed event may need some specific plugin array ordering, which I think may be confusing to be used. Because if there is a plugin that wanted us to announce something and it is after the new plugin, it may be missed.
Maybe we can just add a new PluginEvent for announcing and let the new plugin handle it exclussively. Do you think this could be a good way?

I'm ok to have a new event type. But I also feel ContentChangedEvent should be fine, think about this:

• AnnouncePlugin
• SomeOtherPlugin

When SomeOtherPlugin trigger a ContentChangedEvent, it is a new event so that AnnouncePlugin will get it, it doesn't matter where SomeOtherPlugin is.

Ah ok, that makes sense.

I was thinking more about an scenario where a ContentChanged was triggered and each plugin could modify the announce data in the event. I will try to refactor it to this.