Thursday Jan 17, 2013

How to create cascading (depending) auto suggest behavior using BC4J

In continuation to my previous blog on "How to create multi level cascading (dependent) list of values using BC4J", i am trying to leverage a similar usecase using af:autoSuggestBehavior in this article. Though the usecase looks same, the implementation is slightly different for this.

Let us assume a usecase where we have some text fields with auto suggest feature enabled, and their suggested items could be dependent on one other. For ex : Country, State and City.

This could be modeled by having an EO and VO created based on Person table and read-only look-up VOs created based on Country, State and City tables.

model.jpg

VOs.jpg

Implementing the dependency between LOVs is pretty straight forward. However, implementing the dependency between the auto suggest items is not. In order to achieve the dependency, first we would need couple of methods returning current row's CountryId and StateId. We could add them up in the AMImpl class.

public Number getCurrentCountryId(){
return (Number) this.getPersonView1().getCurrentRow().getAttribute("CountryId");
}

public Number getCurrentStateId(){
return (Number) this.getPersonView1().getCurrentRow().getAttribute("StateId");
}

As we need to filter out the States based on the Country and the City based on the Country & State, we would need to modify the query of these two VOs to include a bind variable in the where clause.

whereClause.jpg

For having the auto suggest, we need to have a view criteria defined for all the three look-up VOs (CountryView, StateView and CityView).

CountryVC.jpg

StateVC.jpg

CityVC.jpg

Generate VOImpl classes for Country, State and City VOs (with Include bind variable accessors option checked), and then expose setBindCountryName (in Country VO), setBindStateName (in State VO) and setBindCityName (in City VO) methods as client interfaces.

And the last part on the model is to pass the current row's CountryId and StateId to the Bind Variables defined in the State and City VOs. Also, we need to get the VCs created above to be executed by default (By editing the VO instance in the AM's data model), so that the auto suggest list would be filtered as and when the users type.

CountryViewAM.jpg

StateViewAM.jpg

CityViewAM.jpg

Here, we specify groovy expression for the CountryId and StateId as adf.object.applicationModule.<methodName>. For more information about using groovy expressions, check out this : http://www.oracle.com/technetwork/developer-tools/jdev/introduction-to-groovy-128837.pdf .

With this, we are done with setting up the model layer for the auto suggest dependency.

In the View layer, we would create an ADF Form based on the Person VO, with all the navigation buttons.

PersonJSPX.jpg

In order to construct the onSuggest items, we would create Tree Bindings for Country VO, State VO and City VO, along with method action bindings for the setBindCountryName, setBindStateName and setBindCityName methods.

pagedef.jpg

Now, we could add af:autoSuggestBehavior for CountryId, StateId and CityId fields. Then, add onSuggest methods in backing bean for populating the on suggest items for each fields.

onSuggest method for Country field :

public List onCountrySuggest(String searchCountryName) {
ArrayList<SelectItem> selectItems = new ArrayList<SelectItem>();

System.out.println(searchCountryName);
//get access to the binding context and binding container at runtime
BindingContext bctx = BindingContext.getCurrent();
BindingContainer bindings = bctx.getCurrentBindingsEntry();
//set the bind variable value that is used to filter the View Object
//query of the suggest list. The View Object instance has a View
//Criteria assigned
OperationBinding setVariable = (OperationBinding) bindings.get("setBind_CountryName");
setVariable.getParamsMap().put("value", searchCountryName);
setVariable.execute();
//the data in the suggest list is queried by a tree binding.
JUCtrlHierBinding hierBinding = (JUCtrlHierBinding) bindings.get("CountryView1");


//re-query the list based on the new bind variable values
hierBinding.executeQuery();

//The rangeSet, the list of queries entries, is of type
//JUCtrlValueBndingRef.
List<JUCtrlValueBindingRef> displayDataList = hierBinding.getRangeSet();

for (JUCtrlValueBindingRef displayData : displayDataList){
Row rw = displayData.getRow();
//populate the SelectItem list
selectItems.add(new SelectItem(
(Integer)rw.getAttribute("Id"),
(String)rw.getAttribute("Name")));
}

return selectItems;
}

onSuggest method for State field :


public List onStateSuggest(String searchStateName) {
ArrayList<SelectItem> selectItems = new ArrayList<SelectItem>();

System.out.println(searchStateName);
//get access to the binding context and binding container at runtime
BindingContext bctx = BindingContext.getCurrent();
BindingContainer bindings = bctx.getCurrentBindingsEntry();
//set the bind variable value that is used to filter the View Object
//query of the suggest list. The View Object instance has a View
//Criteria assigned
OperationBinding setVariable = (OperationBinding) bindings.get("setBind_StateName");
setVariable.getParamsMap().put("value", searchStateName);
setVariable.execute();
//the data in the suggest list is queried by a tree binding.
JUCtrlHierBinding hierBinding = (JUCtrlHierBinding) bindings.get("StateView1");


//re-query the list based on the new bind variable values
hierBinding.executeQuery();

//The rangeSet, the list of queries entries, is of type
//JUCtrlValueBndingRef.
List<JUCtrlValueBindingRef> displayDataList = hierBinding.getRangeSet();

for (JUCtrlValueBindingRef displayData : displayDataList){
Row rw = displayData.getRow();
//populate the SelectItem list
selectItems.add(new SelectItem(
(Integer)rw.getAttribute("Id"),
(String)rw.getAttribute("Name")));
}

return selectItems;
}

onSuggest method for City field :

public List onCitySuggest(String searchCityName) {
ArrayList<SelectItem> selectItems = new ArrayList<SelectItem>();

System.out.println(searchCityName);
//get access to the binding context and binding container at runtime
BindingContext bctx = BindingContext.getCurrent();
BindingContainer bindings = bctx.getCurrentBindingsEntry();
//set the bind variable value that is used to filter the View Object
//query of the suggest list. The View Object instance has a View
//Criteria assigned
OperationBinding setVariable = (OperationBinding) bindings.get("setBind_CityName");
setVariable.getParamsMap().put("value", searchCityName);
setVariable.execute();
//the data in the suggest list is queried by a tree binding.
JUCtrlHierBinding hierBinding = (JUCtrlHierBinding) bindings.get("CityView1");


//re-query the list based on the new bind variable values
hierBinding.executeQuery();

//The rangeSet, the list of queries entries, is of type
//JUCtrlValueBndingRef.
List<JUCtrlValueBindingRef> displayDataList = hierBinding.getRangeSet();

for (JUCtrlValueBindingRef displayData : displayDataList){
Row rw = displayData.getRow();
//populate the SelectItem list
selectItems.add(new SelectItem(
(Integer)rw.getAttribute("Id"),
(String)rw.getAttribute("Name")));
}

return selectItems;
}

Once after this, we could bind this to the af:autoSuggestBehavior's suggestedItems property

<af:inputText value="#{bindings.CountryId.inputValue}" label="#{bindings.CountryId.hints.label}"
columns="#{bindings.CountryId.hints.displayWidth}"
autoSubmit="true"
shortDesc="#{bindings.CountryId.hints.tooltip}" id="it3">
<af:autoSuggestBehavior suggestedItems="#{viewScope.AutoSuggestBean.onCountrySuggest}"/>
</af:inputText>
<af:inputText value="#{bindings.StateId.inputValue}" label="#{bindings.StateId.hints.label}"
columns="#{bindings.StateId.hints.displayWidth}"
autoSubmit="true" partialTriggers="it3"
shortDesc="#{bindings.StateId.hints.tooltip}" id="it4">
<af:autoSuggestBehavior suggestedItems="#{viewScope.AutoSuggestBean.onStateSuggest}"/>
</af:inputText>
<af:inputText value="#{bindings.CityId.inputValue}" label="#{bindings.CityId.hints.label}"
columns="#{bindings.CityId.hints.displayWidth}"
autoSubmit="true" partialTriggers="it4"
shortDesc="#{bindings.CityId.hints.tooltip}" id="it5">
<af:autoSuggestBehavior suggestedItems="#{viewScope.AutoSuggestBean.onCitySuggest}"/>
</af:inputText>

Finally, our output would be

output1.jpg

output2.jpg

output3.jpg

Monday Nov 26, 2012

Restrict number of characters to be typed for af:autoSuggestBehavior

When using AutoSuggestBehavior for a UI Component, the auto suggest list is displayed as soon as the user starts typing in the field. In this article, we will find how to restrict the autosuggest list to be displayed till the user types in couple of characters.

This would be more useful in the low latency networks and also the autosuggest list is bigger. We could display a static message to let the user know that they need to type in more characters to get a list for picking a value from. Final output we would expect is like the below image

FinalOutput1.jpgFinalOutput2.jpg

Lets see how we can implement this. Assuming we have an input text for the users to enter the country name and an autosuggest behavior is added to it.

<af:inputText label="Country" id="it1">
                    <af:autoSuggestBehavior />
                </af:inputText>
Also, assuming we have a VO (we'll name it as CountryView for this example), with a view criteria to filter out the VO based on the bind variable passed.

VC.jpg

Now, we would generate View Impl class from the java node (including bind variables) and then expose the setter method of the bind variable to client interface.

In the View layer, we would create a tree binding for the VO and the method binding for the setter method of the bind variable exposed above, in the pagedef file

Pagedef.jpg

As we've already added an input text and an autosuggestbehavior for the test, we would not need to build the suggested items for the autosuggest list.Let us add a method in the backing bean to return us List of select items to be bound to the autosuggest list.

 padding: 5px; background-color: #fbfbfb; min-height: 40px; width: 544px; height: 168px; overflow: auto;">        public List onSuggest(String searchTerm) {
        ArrayList<SelectItem> selectItems = new ArrayList<SelectItem>();
        if(searchTerm.length()>1) {
        //get access to the binding context and binding container at runtime
        BindingContext bctx = BindingContext.getCurrent();
        BindingContainer bindings = bctx.getCurrentBindingsEntry();
        //set the bind variable value that is used to filter the View Object
        //query of the suggest list. The View Object instance has a View
        //Criteria assigned
        OperationBinding setVariable = (OperationBinding) bindings.get("setBind_CountryName");
        setVariable.getParamsMap().put("value", searchTerm);
        setVariable.execute();
        //the data in the suggest list is queried by a tree binding.
        JUCtrlHierBinding hierBinding = (JUCtrlHierBinding) bindings.get("CountryView1");
                                                                                                                                              
        //re-query the list based on the new bind variable values hierBinding.executeQuery();
        //The rangeSet, the list of queries entries, is of type
        //JUCtrlValueBndingRef.
        List<JUCtrlValueBindingRef> displayDataList = hierBinding.getRangeSet();
        
        for (JUCtrlValueBindingRef displayData : displayDataList){
            Row rw = displayData.getRow();
            //populate the SelectItem list
            selectItems.add(new SelectItem(
            (String)rw.getAttribute("Name"),
            (String)rw.getAttribute("Name")));
            }
        
        }
        else{
            SelectItem a = new SelectItem("","Type in two or more characters..","",true);
            selectItems.add(a);
        }
        return selectItems;
    }

So, what we are doing in the above method is, to check the length of the search term and if it is more than 1 (i.e 2 or more characters), the return the actual suggest list. Otherwise, create a read only select item

new SelectItem("","Type in two or more characters..","",true);

and add it to the list of suggested items to be displayed. The last parameter for the SelectItem (boolean) is to make it as readOnly, so that users would not be able to select this static message from the displayed list.

Finally, bind this method to the input text's autosuggestbehavior's suggestedItems property.

<af:inputText label="Country" id="it1">
        <af:autoSuggestBehavior
              suggestedItems="#{AutoSuggestBean.onSuggest}"/>
 </af:inputText>
About

Tips & Tricks from Arun on JDev ADF, Forms, SQL & PL/SQL.

Search

Archives
« April 2014
SunMonTueWedThuFriSat
  
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
   
       
Today