ZK Binding NotifyChange not work on onChanging Event? - binding

Question

I currently use ZK for web-development. Here is my case:
I implement instant search, once text change=> perform search.
Zul File
<textbox id="textSearch" sclass="search_text">
<attribute name="onChanging">
lbOnChangingSearch.setValue(event.getValue());
vm.onChangingTextSearch();
</attribute>
</textbox>
<label id="lbOnChangingSearch" visible="false"></label>
<grid id="gridChapter" model="#load(vm.chapterInPage)">
....
</grid>
Controller code
ListModelList<ChapterJoinComic> chapterInPage;
public ListModelList<ChapterJoinComic> getChapterInPage() {
return chapterInPage;
}
#NotifyChange({ "topComics", "chapterInPage"} )
#Command
public void onChangingTextSearch() {
FilterObject fo = getFilterObject();
fo.setSearch_str(lbOnChangingSearch.getValue());
//
doSearch(fo); // Change chapterInPage
// Manually post Not
BindUtils.postNotifyChange(null,null,this.chapterInPage,"chapterInPage");
}
Problem
After call onChangingText search, Grid dont update databinding.
But if I continue change text (more call onChangingTextSearch ). The Grid will update, but the updated value is the previous value.
It seems the Grid is a-step slower than my latest Model object.
Note If I use onOK instead of onChanging event, the databinding works well.
Anyone can help me. Thanks in advance!

Answer 1

In addition of Malte his answer.
Textbox only sends data to the server with the onChange event to avoid needless network traffic.
If you want to send data to the server with the onChanging event, you need to do :
<textbox instant="true" />
In this case the client will update almost instantly to the server (if you type fast, it will be when you stop typing)

Answer 2

You should remove the BindUtils.postnotifyChange when you use #NotifyChange already, and you use it wrong anyway: the third parameter should be this instead of this.chapterInPage. The JavaDoc explains that you need to specify the bean whose property is changing and the name of the property.
Furthermore, replace your onChanging attribute with the proper way to call a command:
<textbox id="textSearch" sclass="search_text"
onChanging="#command('onChangingTextSearch')" />
Consult the documentation for more information on how to use commands. I think because you do not use the command as a command, the #NotifyChange is not triggered. And your postNotifyChange is wrong, as I said.
Let me know if that works or if there are other problems remaining.
EDIT
I just re-created an example on my own, and it seems to work. Try it like this:
ViewModel --------------------------------
private String searchText = "";
#NotifyChange({"chapterInPage", "searchText"})
#Command
public void onChangingTextSearch(#BindingParam("text") String searchText)
{
this.searchText = searchText;
}
public String getSearchText()
{
return searchText;
}
public ListModelList<String> getChapterInPage()
{
return new ListModelList<>(searchText.split(""));
}
zul --------------------------------------
<textbox onChanging="#command('onChangingTextSearch', text=event.value)" />
<label id="lbl" value="#load(model.searchText)" />
<listbox model="#load(model.chapterInPage)" />
Note that I use command binding to call the search method in the model instead of calling it "manually" in an onChanging listener. This way, I actually execute it as a command, which triggers the notifyChange. When you call it like vm.onChangingTextSearch() in a listener, the #NotifyChange is ignored.
This way, it works as expected, and with every character typed (well, after a couple of millisenconds delay), the list updates. Another advantage is that you do not have to bind your label into the view model, something that zk's documentation discourages.
Can you try to link your zul and model like this and tell me if it works. If it doesn't, you might want to try to create an example on zkFiddle that re-produces your code's behavior.