[ovirt-devel] Frontend code - introducing GinUiBinder

Hi guys, Martin's GinUiBinder patch [1] just landed into master branch. [1] http://gerrit.ovirt.org/#/c/34954/ This patch allows the use of dependency injection for widgets declared in GWT UiBinder templates. Let's take a look at AbstractVmPopupWidget.ui.xml template: <vm:SerialNumberPolicyWidget ui:field="serialNumberPolicyEditor"/> Inside the "owner" widget, AbstractVmPopupWidget class: @UiField(provided = true) // we need manual instantiation public SerialNumberPolicyWidget serialNumberPolicyEditor; We use "provided = true" in order to manually instantiate SerialNumberPolicyWidget, because this widget accepts some constructor parameters: public SerialNumberPolicyWidget( CommonApplicationTemplates applicationTemplates, ... ) So in AbstractVmPopupWidget, we need to do following: serialNumberPolicyEditor = new SerialNumberPolicyWidget(...) The "provided = true" + "new SerialNumberPolicyWidget(...)" is essentially a boilerplate that adds to overall complexity. Now, let's revisit above example using GinUiBinder. First, in AbstractVmPopupWidget class: @UiField // no need for manual instantiation public SerialNumberPolicyWidget serialNumberPolicyEditor; Then, in SerialNumberPolicyWidget class: @Inject // inject dependencies into this widget public SerialNumberPolicyWidget( CommonApplicationTemplates applicationTemplates, ... ) And finally, we can remove following line: // this is no longer needed, GinUiBinder handles it for us serialNumberPolicyEditor = new SerialNumberPolicyWidget(...) The complete example can be seen here: http://gerrit.ovirt.org/#/c/34954/4/frontend/webadmin/modules/gwt-common/... I encourage every UI maintainer to revisit existing code with regard to @UiField(provided = true) and refactor/improve it to take advantage of @Inject in specific widget classes. Let me (or Martin) know if you have any questions. Regards, Vojtech