Binding Contents of a ListBox to Selected Item from Another Listbox w/JSF & Managed Beans
- by nieltown
Hi there! I currently have a JSF application that uses two listboxes. The first, say ListBox1, contains a list of manufacturers; each option comes from the database (via a method getManufacturers in a class called QueryUtil), is populated dynamically, and its value is an integer ID. This part works so far.
My goal is to populate a second listbox, say ListBox2, with a list of products sold by the manufacturer. This list of products will come from the database as well (products are linked to a manufacturer via a foreign key relationship, via a method getProducts in my QueryUtil class). How do I go about doing this? Please bear in mind that I've been working with JSF for under 24 hours; I'm willing to accept the fact that I'm missing something very rudimentary.
Again, I've been able to populate the list of manufacturers just fine; unfortunately, adding the Products component gives me java.lang.IllegalArgumentException: argument type mismatch
faces-config.xml
<managed-bean>
<managed-bean-name>ProductsBean</managed-bean-name>
<managed-bean-class>com.nieltown.ProductsBean</managed-bean-class>
<managed-bean-scope>request</managed-bean-scope>
<managed-property>
<property-name>manufacturers</property-name>
<property-class>java.util.ArrayList</property-class>
<value>#{manufacturers}</value>
</managed-property>
<managed-property>
<property-name>selectedManufacturer</property-name>
<property-class>java.lang.Integer</property-name>
<value>#{selectedManufacturer}</value>
</managed-property>
<managed-property>
<property-name>products</property-name>
<property-class>java.util.ArrayList</property-class>
<value>#{products}</value>
</managed-property>
<managed-property>
<property-name>selectedProduct</property-name>
<property-class>java.lang.Integer</property-name>
<value>#{selectedProducts}</value>
<managed-property>
</managed-bean>
com.nieltown.ProductsBean
public class ProductsBean {
private List<SelectItem> manufacturers;
private List<SelectItem> products;
private Integer selectedManufacturer;
private Integer selectedProduct;
public ProductsBean() {}
public Integer getSelectedManufacturer(){
return selectedManufacturer;
}
public void setSelectedManufacturer(Integer m){
selectedManufacturer = m;
}
public Integer getSelectedProduct(){
return selectedProduct;
}
public void setSelectedProduct(Integer p){
selectedProduct = p;
}
public List<SelectItem> getManufacturers(){
if(manufacturers == null){
SelectItem option;
plans = new ArrayList<SelectItem>();
QueryUtil qu = new QueryUtil();
Map<Integer, String> manufacturersMap = qu.getManufacturers();
for(Map.Entry<Integer, String> entry : manufacturersMap.entrySet()){
option = new SelectItem(entry.getKey(),entry.getValue());
manufacturers.add(option);
}
}
return manufacturers;
}
public void setManufacturers(List<SelectItem> l){
manufacturers = l;
}
public List<SelectItem> getProducts(){
if(products == null){
SelectItem option;
products = new ArrayList<SelectItem>();
if(selectedPlan != null){
PMTQueryUtil pqu = new PMTQueryUtil();
Map<Integer, String> productsMap = pqu.getProducts();
for(Map.Entry<Integer, String> entry : productsMap.entrySet()){
option = new SelectItem(entry.getKey(),entry.getValue());
products.add(option);
}
}
}
return products;
}
public void setProducts(List<SelectItem> l){
products = l;
}
}
JSP fragment
<h:selectOneListbox id="manufacturerList"
value="#{ProductsBean.selectedManufacturer}"
size="10">
<f:selectItems value="#{ProductsBean.manufacturers}" />
</h:selectOneListbox>
<h:selectOneListbox id="productList"
value="#{PendingPlansBean.selectedProduct}"
size="10">
<f:selectItems binding="#{ProductsBean.products}" />
</h:selectOneListbox>
