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MApplication.getDescriptors() returns an empty list [message #1041138]

Sun, 14 April 2013 13:38

Eclipse User

When I call MApplication.getDescriptors() (e.g. in a handler), I see the method returning an empty list. In my application model, I defined various parts and, thus, I'd rather expect a non empty list of MPartDescriptor instances, one for each xsi:type="basic:Part" element I defined in my application model.

Do I have to do something for that I get the expected result?

The background of my question is that the org.eclipse.e4.ui.internal.workbench.swt.handlers.ShowViewHandler displays an empty dialog window in my pure E4 application.

Re: MApplication.getDescriptors() returns an empty list [message #1043872 is a reply to message #1041138]

Thu, 18 April 2013 04:06

Eclipse User

In a pure e4 context, defining a MPart does not automatically mean defining a MPartDescriptor. MPDs are different things in terms of model elements. The MApplication#getDescriptors() will return the list of MPartDescriptors that were explicitly defined, be it programmatically or through the tooling editor.

Re: MApplication.getDescriptors() returns an empty list [message #1045156 is a reply to message #1041138]

Fri, 19 April 2013 17:31

Eclipse User

Thank you, Sopot, for your reply.
Thanks to this hint I added some descriptors nodes to my application model (having the tags 'View' and 'categoryTag:My Category'). Now, the ShowViewHandler works as expected.

How can I define a PartDescriptor in a model fragment?

I tried it straight forward by adding an element xsi:type="basic_1:PartDescriptor" to the fragments node (in the fragments model). Doing this, however, results in the following error at startup time:
===
java.lang.ClassCastException: org.eclipse.e4.ui.model.application.descriptor.basic.impl.PartDescriptorImpl cannot be cast to org.eclipse.e4.ui.model.application.ui.MUIElement
at org.eclipse.e4.ui.model.application.ui.impl.ElementContainerImpl$1.validate(ElementContainerImpl.java:1)
at org.eclipse.emf.common.util.BasicEList.addUnique(BasicEList.java:437)
at org.eclipse.emf.common.notify.impl.NotifyingListImpl.doAddUnique(NotifyingListImpl.java:387)
at org.eclipse.emf.common.notify.impl.NotifyingListImpl.addUnique(NotifyingListImpl.java:371)
at org.eclipse.emf.common.util.AbstractEList.add(AbstractEList.java:339)
at org.eclipse.e4.ui.model.internal.ModelUtils.mergeList(ModelUtils.java:201)
at org.eclipse.e4.ui.model.internal.ModelUtils.merge(ModelUtils.java:135)
at org.eclipse.e4.ui.model.fragment.impl.StringModelFragmentImpl.merge(StringModelFragmentImpl.java:288)
at org.eclipse.e4.ui.internal.workbench.ModelAssembler.processModel(ModelAssembler.java:167)
at org.eclipse.e4.ui.internal.workbench.ResourceHandler.loadMostRecentModel(ResourceHandler.java:220)
at org.eclipse.e4.ui.internal.workbench.swt.E4Application.loadApplicationModel(E4Application.java:366)
at org.eclipse.e4.ui.internal.workbench.swt.E4Application.createE4Workbench(E4Application.java:220)
at org.eclipse.e4.ui.internal.workbench.swt.E4Application.start(E4Application.java:132)
at org.elbe.relations.internal.RelationsApplication.start(RelationsApplication.java:60)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:353)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:180)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:629)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:584)
at org.eclipse.equinox.launcher.Main.run(Main.java:1438)
at org.eclipse.equinox.launcher.Main.main(Main.java:1414)
===
Here is the element I added to the fragment e4xmi:
===
<elements xsi:type="basic_1:PartDescriptor" xmi:id="_telpcKk1EeKhmYrZRO6sPg" label="My View" iconURI="platform:/plugin/org.elbe.relations.defaultBrowser/icons/relations.gif" tooltip="My View" contributionURI="bundleclass://org.elbe.relations.defaultBrowser/org.elbe.relations.defaultbrowser.internal.DefaultBrowserPart">
<tags>View</tags>
<tags>categoryTag:My Category</tags>
</elements>
===

Re: MApplication.getDescriptors() returns an empty list [message #1046705 is a reply to message #1045156]

Mon, 22 April 2013 04:52

Eclipse User

The casting to MUIElement is weird. What's the parent you are trying to stick the PartDescriptor to? If you're not sure paste the whole fragment.e4xmi.

Re: MApplication.getDescriptors() returns an empty list [message #1048250 is a reply to message #1046705]

Wed, 24 April 2013 04:12

Eclipse User

I've just added a PartDescriptor to the collection of Elements in the Model Fragment editor.
Therefore, the parent is a xsi:type="fragment:StringModelFragment" node.

Here's the fragment.e4xmi:

<?xml version="1.0" encoding="ASCII"?>
<fragment:ModelFragments xmi:version="2.0" xmlns:xmi="http://www.omg.org/XMI" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:basic="http://www.eclipse.org/ui/2010/UIModel/application/ui/basic" xmlns:basic_1="http://www.eclipse.org/ui/2010/UIModel/application/descriptor/basic" xmlns:commands="http://www.eclipse.org/ui/2010/UIModel/application/commands" xmlns:fragment="http://www.eclipse.org/ui/2010/UIModel/fragment" xmlns:menu="http://www.eclipse.org/ui/2010/UIModel/application/ui/menu" xmlns:ui="http://www.eclipse.org/ui/2010/UIModel/application/ui" xmi:id="_UUOPgDTFEeKJCcF8Dmjvqg">
<imports xsi:type="commands:Command" xmi:id="_-qVgAEI4EeK4WpHp4ZQ4aQ" elementId="org.elbe.relations.command.item.edit"/>

<fragments xsi:type="fragment:StringModelFragment" xmi:id="_gwxPwDTFEeKJCcF8Dmjvqg" featurename="children" parentElementId="relations.views" positionInList="first">

<elements xsi:type="basic:Part" xmi:id="_yf8x0DTGEeKJCcF8Dmjvqg" elementId="org.elbe.relations.browser.default" contributionURI="bundleclass://org.elbe.relations.defaultBrowser/org.elbe.relations.defaultbrowser.internal.DefaultBrowserPart" label="Relations" iconURI="platform:/plugin/org.elbe.relations.defaultBrowser/icons/relations.gif" tooltip="Relations" bindingContexts="_UsLV0EJVEeK4WpHp4ZQ4aQ" closeable="true">
<menus xsi:type="menu:PopupMenu" xmi:id="_KOgOIEI2EeK4WpHp4ZQ4aQ" elementId="org.elbe.relations.defaultbrowser.popup">
<children xsi:type="menu:HandledMenuItem" xmi:id="_XbYfIEI2EeK4WpHp4ZQ4aQ" elementId="defaultbrowser.popup:item.edit" label="ausgewähltes Item: editieren" iconURI="platform:/plugin/org.elbe.relations.defaultBrowser/icons/edit.gif" tooltip="" command="_-qVgAEI4EeK4WpHp4ZQ4aQ">
<visibleWhen xsi:type="ui:CoreExpression" xmi:id="_Uvnh0EJJEeK4WpHp4ZQ4aQ" coreExpressionId="org.elbe.relations.definition.browser.popup.item"/>
</children>
</menus>
</elements>

<elements xsi:type="basic_1:PartDescriptor" xmi:id="_telpcKk1EeKhmYrZRO6sPg" label="My View" iconURI="platform:/plugin/org.elbe.relations.defaultBrowser/icons/relations.gif" tooltip="My View" contributionURI="bundleclass://org.elbe.relations.defaultBrowser/org.elbe.relations.defaultbrowser.internal.DefaultBrowserPart">
<tags>View</tags>
<tags>categoryTag:My Category</tags>
</elements>

</fragments>
</fragment:ModelFragments>

Re: MApplication.getDescriptors() returns an empty list [message #1048273 is a reply to message #1048250]

Wed, 24 April 2013 04:42

Eclipse User

No, no don't do it that way. When I say parent I don't mean the parent in the left-side tree in the editor. Every model element you add in the fragment has to have a parent in the main application model. Suppose you have two part stacks in the main model and you add a part through a fragment. In order to resolve ambiguity (which of the two part stacks you should add the part to?) you supply the ID of the parent model element (the correct part stack). Add the descriptor but in the model fragment metadata add it as a 'child' (feature) of your MApplication (supply the MApp's id and 'descriptors' featurename).

Ultimately it should look something like :

<fragments xsi:type="fragment:StringModelFragment" xmi:id="_hmhn4Ky6EeKLN_c01nrL9A" featurename="descriptors" parentElementId="org.eclipse.e4.ide.application">
    <elements xsi:type="basic:PartDescriptor" xmi:id="_hmhn4ay6EeKLN_c01nrL9A" elementId="popupmenutest.partdescriptor.0"/>
  </fragments>

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