问题
I created an eclipse-rcp's project's plugin.xml with a new command with a parameter.
ArrayList<parameterization> parameters = new ArrayList<parameterization>();
IParameter iparam;
//get the command from plugin.xml
IWorkbenchWindow window = PlatformUI.getWorkbench().getActiveWorkbenchWindow();
ICommandService cmdService = (ICommandService)window.getService(ICommandService.class);
Command cmd = cmdService.getCommand("org.ipiel.demo.commands.click");
//get the parameter
iparam = cmd.getParameter("org.ipiel.demo.commands.click.paramenter1");
Parameterization params = new Parameterization(iparam, "commandValue");
parameters.add(params);
//build the parameterized command
ParameterizedCommand pc = new ParameterizedCommand(cmd, parameters.toArray(new Parameterization[parameters.size()]));
//execute the command
IHandlerService handlerService = (IHandlerService)window.getService(IHandlerService.class);
handlerService.executeCommand(pc, null);
I tried this example to pass parameters and it worked.
The issue in this example that I could pass only parameters of type String. ( because Parameterization )
I want to pass parameter of hash map and in general to pass any object.
I tried this code
IServiceLocator serviceLocator = PlatformUI.getWorkbench();
ICommandService commandService = (ICommandService) serviceLocator.getService(ICommandService.class);
ExecutionEvent executionEvent = new ExecutionEvent(cmd, paramArray, null, null);
cmd.executeWithChecks(executionEvent);
but it didn't work the parameters didn't move ( it was null)
Could you please help to to move object as parameter in command ?
回答1:
Since it would get confusing to add another solution to my first answer, I'll provide another one for a second solution. The choices I gave were " A) use the selected object of the "Execution Event" (examine that, it contains a lot of infos). B) you can use AbstractSourceProvider, so you can pass your object to the application context."
A) can be used in your Handler if your object is the selection of a Structured Object like a Tree:
MyObject p = (MyObject) ((IStructuredSelection) HandlerUtil.getCurrentSelection(event)).getFirstElement();
B) The usage of a Source provider is a bit more tricky. The main idea is, that you add your object to the application context. The important snippets for Eclipse 3.x from a project that I set up after I read this blog (note: it is in german and the example it provides doesn't work): In your plugin.xml add:
<extension point="org.eclipse.ui.services">
<sourceProvider
provider="com.voo.example.sourceprovider.PersonSourceProvider">
<variable
name="com.voo.example.sourceprovider.currentPerson"
priorityLevel="activePartId">
</variable>
</sourceProvider>
Set up your own SourceProvider. Calling the "getCurrentState" you can get the variable (your Person object in this case) of that SourceProvider:
public class PersonSourceProvider extends AbstractSourceProvider{
/** This is the variable that is used as reference to the SourceProvider
*/
public static final String PERSON_ID = "com.voo.example.sourceprovider.currentPerson";
private Person currentPerson;
public PersonSourceProvider() {
}
@Override
public void dispose() {
currentPerson = null;
}
**/**
* Used to get the Status of the source from the framework
*/
@Override
public Map<String, Person> getCurrentState() {
Map<String, Person> personMap = new HashMap<String, Person>();
personMap.put(PERSON_ID, currentPerson);
return personMap;
}**
@Override
public String[] getProvidedSourceNames() {
return new String[]{PERSON_ID};
}
public void personChanged(Person p){
if (this.currentPerson != null && this.currentPerson.equals(p)){
return;
}
this.currentPerson = p;
fireSourceChanged(ISources.ACTIVE_PART_ID, PERSON_ID, this.currentPerson);
}
}
In your View you register to the SourceProvider and set the Object to the object you want to transfer to your Handler.
public void createPartControl(Composite parent) {
viewer = new TreeViewer(parent);
viewer.setLabelProvider(new ViewLabelProvider());
viewer.setContentProvider(new ViewContentProvider());
viewer.setInput(rootPerson);
getSite().setSelectionProvider(viewer);
viewer.addSelectionChangedListener(new ISelectionChangedListener() {
@Override
public void selectionChanged(SelectionChangedEvent event) {
Person p = null;
if (event.getSelection() instanceof TreeSelection) {
TreeSelection selection = (TreeSelection) event.getSelection();
if (selection.getFirstElement() instanceof Person) {
p = (Person) selection.getFirstElement();
}
}
if (p==null) {
return;
}
IWorkbenchWindow window = PlatformUI.getWorkbench().getActiveWorkbenchWindow();
ISourceProviderService service = (ISourceProviderService) window.getService(ISourceProviderService.class);
PersonSourceProvider sourceProvider = (PersonSourceProvider) service.getSourceProvider(PersonSourceProvider.PERSON_ID);
sourceProvider.personChanged(p);
}
});
}
And in your Handler you can just call the PersonSourceProvider#getCurrentState to get your Objects back.
Advantage of this method is, that you can use the Objectd anywhere you want. E.g. you can even set up a PropertyTester to enable/disable UI elements according to the currently selected Object.
回答2:
The Parameterized Command does only accept Strings. Here is an example for smaller objects:
Disclaimer: this is for Eclipse 3.x. I am not using Eclipse 4.x a lot, so you might have to adapt there in case you need it.
Create a Pluginproject (com.voo.example.commandparameter.advanced) with a View (com.voo.example.commandparameter.advanced.view) , a Command (com.voo.example.commandparameter.advanced.sysoCommand) with menu entry and Handler(com.voo.example.commandparameter.advanced.sysoCommand), and a universal Object (MyTestObject).
The Command needs a Parameter and a Parametertype in the plugin.xml, that gets passed to it:
<extension
point="org.eclipse.ui.commands">
<command
id="com.voo.example.commandparameter.advanced.sysoCommand"
name="SysoCommand">
<commandParameter
id="myObject"
name="object"
optional="true"
typeId="com.voo.example.commandparameter.advanced.testType">
</commandParameter>
</command>
<commandParameterType
id="com.voo.example.commandparameter.advanced.testType"
type="com.voo.example.commandparameter.advanced.MyTestObject">
</commandParameterType>
In the Object you set atrtibutes like name and street and define a convertToString method like that:
public String convertToString() {
return getName() +",,,"+ getStreet();
}
(you can override the toString method, too. I just used that method to set weired delimiters to the returned String) And in a Class MyParamterConverter you can transfer it back:
public class MyParameterConverter extends AbstractParameterValueConverter {
public MyParameterConverter() {
}
@Override
public String convertToString(Object parameterValue)
throws ParameterValueConversionException {
return parameterValue.toString();
}
/**
* This will always create a new object. Just keep that in mind
* if you're trying to work with the objects.
*/
@Override
public Object convertToObject(String parameterValue)
throws ParameterValueConversionException {
//Split the String to get the attributes back
String delimiter =",,,";
String[] split = parameterValue.split(delimiter);
String name = split[0];
String street = split [1];
return new MyTestObject(name, street);
}
}
Now you can call the command with a buttonclick in your view, for example:
btnGo.addSelectionListener(new SelectionAdapter() {
@Override
public void widgetSelected(SelectionEvent event) {
MyTestObject testObject = new MyTestObject(textName.getText(),textStreet.getText());
ICommandService cS = (ICommandService)getSite().getService(ICommandService.class);
IHandlerService hS = (IHandlerService)getSite().getService(IHandlerService.class);
Command sysoComm = cS.getCommand("com.voo.example.commandparameter.advanced.sysoCommand");
HashMap<String, String> params = new HashMap<String, String>();
params.put("myObject", testObject.convertToString());
ParameterizedCommand pC = ParameterizedCommand.generateCommand(sysoComm, params);
try {
hS.executeCommand(pC, null);
} catch (Exception e) {
e.printStackTrace();
}
}
});
And the Handler can transform the passed parameters back :
public class MyObjectHandler extends AbstractHandler {
@Override
public Object execute(ExecutionEvent event) throws ExecutionException {
String param1 = event.getParameter("myObject");
MyParameterConverter converter = new MyParameterConverter();
Object convertToObject = null;
try {
convertToObject = converter.convertToObject(param1);
} catch (ParameterValueConversionException e) {
e.printStackTrace();
}
if (convertToObject instanceof MyTestObject) {
MyTestObject to = (MyTestObject) convertToObject;
System.out.println(to.toString());
}
return null;
}
}
This should work for most smaller sized objects that do not change while you pass them. If you need to pass bigger objects, you will have two choices: A) use the selected object of the "Execution Event" (examine that, it contains a lot of infos). B) you can use AbstractSourceProvider, so you can pass your object to the application context.
回答3:
I am not really familiar with this as passing parameters to commands is quite rare. It looks like you have to use commandParameterType in the org.eclipse.ui.commands command definition to define code based on AbstractParameterValueConverter to convert between objects and the string for the parameter value.
回答4:
For a long time I have been focused on delivering an object via a command parameter. But in the end, the easiest workaround is to simply ignore the parameter stuff and put the desired object in a new child IExclipseContext and execute the command with that context. That way your handler gets your object injected.
Caller:
ECommandService commandService = // get commandService...
EHandlerService handlerService = // get handlerService...
IEclipseContext context = // get active or application context...
IEclipseContext childCtx = context.createChild();
childCtx.set(MyObject.class, instancOfMyObject);
ParameterizedCommand command = commandService.createCommand("my.command.id", null);
handlerService.executeHandler(command, childCtx);
In your handler:
@Execute
public void execute(@Optional MyObject myObject) {
if(myObject != null) {
// work with your object
}
}
Voila, no converters or callbacks (i.e. SelectionService) needed...
来源：https://stackoverflow.com/questions/21122233/how-to-pass-object-parameters-in-command