Ext GWT FAQ (Legacy)
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How to get started?
Add the following entry to you projects module xml file.
<inherits name='com.extjs.gxt.ui.GXT'/>
Add the following stylesheet to your host page.
<link rel="stylesheet" type="text/css" href="css/ext-all.css" />
Eclipse Setup (should be similiar for other development enviornments) These instructions assume you have a existing project and launch confifuration.
- Add gxt.jar to the project.
- Right click on project name in 'Package Explorer'.
- Select 'Properties' from content menu.
- Select 'Java Build Path'.
- Select 'Libraries' tab.
- Add the gxt.jar either with 'Add JARs...' or 'Add External JARs...'.
- Add GXT jar to launch configuration.
- Choose Run / Open Run Dialog.
- Select your appropriate launch configuration under 'Java Application'.
- Select the 'Classpath' tab.
- Add the gxt.jar to the classpath.
Place only the following code snippet within the onModuleLoad in a GWT application:
public void onModuleLoad() {
ContentPanel cp = new ContentPanel();
cp.setHeading("Folder Contents");
cp.setSize(250,140);
cp.setPosition(10, 10);
cp.setCollapsible(true);
cp.setFrame(true);
cp.setBodyStyle("backgroundColor: white;");
cp.getHeader().addTool(new ToolButton("x-tool-gear"));
cp.getHeader().addTool(new ToolButton("x-tool-close"));
cp.addText("BogusText");
cp.addButton(new com.extjs.gxt.ui.client.widget.button.Button("Ok"));
cp.setIconStyle("tree-folder-open");
RootPanel.get().add(cp);
cp.layout();
}
What is the required doctype
Ext GWT will support all doctypes supported by GWT
How to refresh a tree?
Use TreeStore.add(M parent, M item, boolean addChildren), TreeLoader.loadChildren(parent) or TreeLoader.load()
Why can't I only add Fields to a FormPanel?
FormPanel has a FormLayout which only renders Fields. If you want to use other widgets, use AdapterField
How to handle selection events on a Tree?
Use TreeBinder.addSelectionChangedListener(..)
How to build a simple Tree with strings?
Just manually add the items, using TreeItem.add(TreeItem), starting with tree.getRootItem().
I have different behaviours in Internet Explorer and Firefox, is it a Ext GWT bug?
Make sure no other stylesheets are loaded that might conflict with Ext GWT - ie only have css/ext-all.css
How do I explicitly listen for mouse clicks on a widget?
widget.sinkEvents(Event.ONCLICK);
widget.addListener(Events.OnClick, new Listener<DomEvent>() {
public void handleEvent(DomEvent be) {
System.out.println("Clicked!");
}
});
In some cases, you can add a selection listener to a widget instead of listening for mouse clicks.
How can I stop an event from continuing (ie beforeXXXX event)?
event.doit=false;
How do I stop a window from closing and ask "Are you sure"?
Use the event.doit=false in a window listener and then add/remove that listener depending on the answer.
Can I use GWT widgets in GXT?
Yes you can.
I've add widgets to a panel, but they don't show up - why?
Call layout() on the panel.
How to create custom components?
You can extend Component, BoxComponent for a sized component, Container for a "layouted" component when you don't want to expose the layout and LayoutContainer for a "layouted" component when you want to expose the layout.