e4 handler 传递自定义对象
e3,e4的commmand默认传递参数均为字符串String类型,不支持自定义类型,但是可以通过把对象转成字符串的形式传递过去后再重新转回对象。
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.
转载于:https://my.oschina.net/zhenghuazhi/blog/1353321
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