Question

public void addTab(String text, Widget widget) {
    TabItem item = new TabItem();
    item.setText(text);
    item.setClosable(true);
//item.add((Widget) new Dashboard());
    tabPanel.add(item);
    tabPanel.setSelection(item);
}

执行时我收到此异常，我怎么能在gxt中解决这个问题。我正在尝试添加标签，但它会出现此异常

com.google.gwt.event.shared.UmbrellaException: Exception caught: null
    at com.google.gwt.event.shared.HandlerManager.fireEvent(HandlerManager.java:129)
    at com.google.gwt.user.client.ui.Widget.fireEvent(Widget.java:129)
    at com.sencha.gxt.widget.core.client.Component.fireEvent(Component.java:293)
    at com.sencha.gxt.widget.core.client.button.IconButton.onClick(IconButton.java:215)
    at com.sencha.gxt.widget.core.client.button.IconButton.onBrowserEvent(IconButton.java:196)
    at com.google.gwt.user.client.DOM.dispatchEventImpl(DOM.java:1351)
    at com.google.gwt.user.client.DOM.dispatchEvent(DOM.java:1307)
    at sun.reflect.GeneratedMethodAccessor44.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103)
    at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71)
    at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:172)
    at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessagesWhileWaitingForReturn(BrowserChannelServer.java:338)

在添加标签时，我得到了这个例外，我该如何解决？

0 个答案: