gwt自定义部件包装方法 [英] gwt custom widget wrap method
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问题描述
public class CustomWidget extends Composite {
public static CustomWidget wrap(com.google.gwt.dom.client.Element元素){
断言Document.get()。getBody()。isOrHasChild(element);
CustomWidget customWiget = new CustomWidget(element); //这行仍然没问题,customWidget的值是
customWiget.onAttach(); //我得到了:java .lang.NullPointerException:null
RootPanel.detachOnWindowClose(customWiget);
返回按钮;
protected CustomWidget(com.google.gwt.dom.client.Element元素){
setElement(element);
$ b
我的包装方法是否正确写入?我在我点评的时候出错了。
元素元素= DOM.getElementById(object);
CustomWidget testKeyValue = CustomWidget.wrap(element);
解决方案
请检查元素! = null
在这行之后:
元素元素= DOM.getElementById(object);
(可能的断言是关闭,所以你当前的代码只会在onAttach()失败。)
my custom widget look like below
public class CustomWidget extends Composite {
public static CustomWidget wrap(com.google.gwt.dom.client.Element element) {
assert Document.get().getBody().isOrHasChild(element);
CustomWidget customWiget = new CustomWidget(element);//this line is still ok,customWidget has value
customWiget.onAttach();//i get Caused by: java.lang.NullPointerException: null
RootPanel.detachOnWindowClose(customWiget);
return button;
}
protected CustomWidget(com.google.gwt.dom.client.Element element) {
setElement(element);
}
}
is my wrap method correctly written? I get error at the point i commented
Element element = DOM.getElementById( object );
CustomWidget testKeyValue= CustomWidget.wrap(element);
解决方案
Please check that element != null
after this line:
Element element = DOM.getElementById( object );
(Probably assertions are turned off, so your current code will only fail in onAttach().)
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