I'm trying to build a dynamic web app in GWT, when widgets are added to the screen I remember their 'name' by setting the Widget.setId, when I want to replace part of the page, I can find the element in question via DOM.getElementById('name'), and its parent using DOM.getParentElement(), and then remove its children.
Now I have a com.google.gwt.dom.client.Element object (the parent). What I want to do is turn this back into a GWT object - in fact it'll be something derived from Panel, so I can add additional Widgets.
How do I go from the Element object back to a Panel object ?
I totally accept I could be going about this the wrong way, in which case is there a better way?
I think your approach to remove widgets from the DOM using DOM.getElementById('name') is not the proper one.
On your case (I am just figuring out what you do), I would keep Java Objects references instead of accessing to them using the DOM.
For instance:
HorizontalPanel panel = new HorizontalPanel();
Widget w = new Widget();
//We add the one widget to the panel
panel.add(w);
//One more widget added
w = new Widget();
panel.add(w);
//Now we remove all the widgets from the panel
for(int i = 0; i < panel.getWidgetCount(); i++){
panel.remove(panel.getWidget(i));
}
UPDATE
Based on your comments, I would propose the following solution. I suppose that you are storing widgets on HorizontalPanel , just apply this solution to your concrete case. I propose to use customized class which inherits from HorizontalPanel and add a Map there to store relationship between names and widgets.
public class MyHorizontalPanel extends HorizontalPanel {
private Map<String, Widget> widgetsMap;
public MyHorizontalPanel(){
super();
widgetsMap = new HashMap<String, Widget>();
}
//We use Map to store the relationship between widget and name
public void aadWidget(Widget w, String name){
this.add(w);
widgetsMap.put(name, w);
}
//When we want to delete and just have the name, we can search the key on the map.
//It is important to remove all references to the widget (panel and map)
public void removeWidget(String name){
this.remove(widgetsMap.get(name));
widgetsMap.remove(name);
}
}
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