Attributes of components in managed Bean actions
I tried to make my component(w/o javascript) change from disabled
to enabled. programmatically in jsf1.2
FacesContext fCtx = FacesContext.getCurrentInstance();
ELContext eCtx = fCtx.getELContext();
System.out.println("...chooseBook...");
UIViewRoot root = fCtx.getViewRoot();
UIComponent comp = rt.findComponent(id);
System.out.print("SSSSS...."+comp);
ValueExpression ve = comp.getValueExpression("disabled");
System.out.print("KKKK...."+((Boolean)ve.getValue(eCtx)));
ve.setValue(eCtx,new Boolean(false));
if(type.equals("UIInput"))
{
((UIInput)comp).setImmediate(true);
((UIInput)comp).updateModel(fCtx);
}
but is is able to get compionent but not its attribute
error
javax.faces.el.EvaluationException: java.lang.NullPointerException
at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:91)
at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:91)
at javax.faces.component.UICommand.broadcast(UICommand.java:383)
at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:447)
at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:752)
at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:97)
at com.sun.faces.lifecycle.LifecycleImpl.phase(LifecycleImpl.java:251)
at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:117)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:244)
at org.apache.catalina.core.ApplicationFilterChain.servletService(ApplicationFilterChain.java:398)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:277)
at org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java:258)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:189)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:611)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:564)
at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:81)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:193)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:611)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:564)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:558)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:1067)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:137)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:611)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:564)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:558)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:1067)
at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:255)
at com.sun.enterprise.web.connector.grizzly.DefaultProcessorTask.invokeAdapter(DefaultProcessorTask.java:618)
at com.sun.enterprise.web.connector.grizzly.DefaultProcessorTask.doProcess(DefaultProcessorTask.java:549)
at com.sun.enterprise.web.connector.grizzly.DefaultProcessorTask.process(DefaultProcessorTask.java:790)
at com.sun.enterprise.web.connector.grizzly.DefaultReadTask.executeProcessorTask(DefaultReadTask.java:326)
at com.sun.enterprise.web.connector.grizzly.DefaultReadTask.doTask(DefaultReadTask.java:248)
at com.sun.enterprise.web.connector.grizzly.DefaultReadTask.doTask(DefaultReadTask.java:199)
at com.sun.enterprise.web.portunif.PortUnificationPipeline$PUTask.doTask(PortUnificationPipeline.java:345)
at com.sun.enterprise.web.connector.grizzly.TaskBase.run(TaskBase.java:252)
at com.sun.enterprise.web.connector.grizzly.ssl.SSLWorkerThread.run(SSLWorkerThread.java:93)
Caused by: java.lang.NullPointerException
at com.htc.faces.BookManipulator.enableComp(BookManipulator.java:127)
at com.htc.faces.BookManipulator.chooseBook(BookManipulator.java:155)
please thanks in case if anybody goes through and reply
