I've got the following config <when-property-is name="isExecute" value="true" />.
Am I able to set property isExecute for module A true and for module B false?
Am I able to change property value by Java?
Does GWT.create read property condition each call or only once (cache)?
What are you trying to achieve? Replacing implementations during runtime? You can use Generator to do this.
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How many instance does binding creates internally for converters.
<Image x:Uid="DisplayedImageUrl" Style="{StaticResource ImageStyle}"
Source="{Binding DisplayedImageURL, Converter={StaticResource ImageLogoConverter}}" />
How many instance does of ImageLogoConverter will be there?
Is it good idea to use converter in ViewModel, if not then what is the best way to access converted value of ViewModel property.
Is it good idea to use converter in ViewModel?
No. Why would you use a converter in a view model where you can return the converted value directly? Converters are used in the view, typically to convert a non-view friendly value that the view model returns.
If not then what is the best way to access converted value of ViewModel property?
You can simpy return an already converted value from the view model, i.e. instead of binding to a Uri property, you may bind directly to an ImageSource property.
This is the recommnded approach if you for example intend to display a lot of elements in a ItemsControl. Then you probably don't want to invoke a converter for each visible element for performance reasons.
I suppose you created the converter as a resource like this:
The number of instances now depends on the scope where the converter resource is declared. If you create it in <Page.Resources>, one instance will be created to be used by the page. If you create it in App.xaml in <Application.Resources> it will be an application-wide instance. Of course, you can even use a narrower scope - create it as a resource of a single control in your XAML tree for example - in any case, a single instance is created when instance of the parent is created.
The situation gets a bit more interesting if you embed it in a ItemTemplate of a list control. Thanks to virtualization, the system will not actually create one instance for each item. Instead, it will create only so many instances as fit on the screen and they get reused when the user scrolls.
Some MVVM developers don't like value converters, but others use them extensively. It really is a matter of preference. In cas you expect the underlying data to change often, it is advisable to keep the code in the converter as performant as possible as it runs on the UI thread.
I've created an extension point for an IConsoleLineTracker, using the following in plugin.xml:
<extension point="org.eclipse.debug.ui.consoleLineTrackers">
<consoleLineTracker
id="com.example.OutputSensor"
class="com.example.OutputSensor"
processType="java">
</consoleLineTracker>
</extension>
The class OutputSensor implements IConsoleLineTracker. Each time the lineAppended method is called, I'm able to see the line that was added. I would like to store the lines being added in an instance of OutputSensor and get access to it from elsewhere in the plugin.
Is there some way I can access the instance of OutputSensor that was created by my plugin? Currently I'm just using static variables in OutputSensor, but I would much rather use an instance of it, preferably a singleton.
Thanks!
There is no general mechanism for getting classes created from extension point definitions.
I also can't see any public API to get the console line trackers that have been created.
So I think the best you can do is set a singleton variable in the constructor of your OutputSensor.
is it possible to override the deferred binding configuration of a inherit module?
Here is a example:
In the module, I want to use, a deferred binding is declared as follows moduleA.gwt.xml:
<replace-with class="A1Impl">
<when-type-is class="A"/>
</replace-with>
<replace-with class="A2Impl">
<when-type-is class="A"/>
<when-property-is name="p" value="1"/>
</replace-with>
The declaration says: Use A1Impl class as default and A2Impl class, if property p has the value 1.
Now, in my app I want to use that module and want P to be 1 (because this controls the above shown, but also a lot of other deferred binding configurations) mymodule.gwt.xml:
<inherits name='moduleA'/>
<set-property name="p" value="1" />
But additionally I want to override the deferred binding configuration of the inherit module to use my own implementation of A. I tried something like this in my module, but it didn't work:
<replace-with class="B1Impl">
<when-type-is class="A"/>
<when-property-is name="p" value="1"/>
</replace-with>
It should say something like this: Do not use A2Impl (declared in inherit module) if property p has the value 1 but use my own implementation B1Impl instead.
Is this possible?
Thanks in advance for any help.
In short, yes, you can redefine any rebind rules that have already been set. Simply inherit the module you are changing, then make your changes after that rebind rule.
<inherits name="package.to.ModuleA" />
<set-property name="p" value="1" />
With the code above, p is always 1, so setting specific rules about what p will be is a little bit silly. Unless p is ever able to be something other than 1, you really don't even need the when-property-is rule.
Your replace-with looks correct as long as it is listed after your inherits statements. For this reason, I always encourage developers to list all inherits rules first, and then go on to any replace-with and generate-with or set-property rules.
For more detail than that, you'll need to post something a little more concrete.
Is it possible to dynamically add and register new attributes to mbean
eg :
<server>
<mbean code="org.jboss.example.MyMbean" name="jboss:service=myMbean,name=MyMbeanExample">
<attribute name="attribute1">value1</attribute>
<attribute name="attribute2">value2</attribute>
<attribute name="attribute3">value3</attribute>
<attribute name="attribute4">value5</attribute>
<attribute name="attribute5">value5</attribute>...
</mbean>
</server>
A new attribute added in jboss-service.xml should be registered in MyMbean dynamically with making any code change in Mbean, can this be done?
Thanks in Advance.
It's hard to answer your question without seeing the code of your DynamicMBean, but I suspect the answer to your question, with the proviso that there be no code changes in the MBean, is no. However, here's an overall approach (taking some liberal assumptions about your code):
A DynamicMBean like this will usually have some sort of map, keyed by the attribute name, and and containing either the value of the attribute (easy), or a value object containing some or all of the following intended to acquire/set the value of the attribute:
a target invocation object,
a method
an array of arguments to the method
When the MBeanInfo of the MBean is requested, the supplied MBeanAttributeInfos should reference the keys in this map (as well as the data type, mutability etc.) You can either generate these on the fly every time MBeanInfo is requested, or keep an updated collection of MBeanAttributeInfo which is updated whenever you add a new attribute.
The methods setAttribute and setAttributes should create a new attribute (by inserting the new key and value into the attribute map) if the set references an attribute that does not already exist.
Since you're using JBoss, if you feel you might want to implement something like this, consider extending JBoss's ServiceDynamicMBeanSupport. It does some, but not all, of the legwork for you.
Looks like the class that is generated for PlaceHistoryMapper is hard-coded to use AbstractPlaceHistoryMapper as the super class.
So, I am trying to work around this by trying to replace this AbstractPlaceHistoryMapper with a custom mapper of mine using deferred binding . I am using the following rule in my *.gwt.xml:
<replace-with class="com.google.gwt.place.impl.AbstractPlaceHistoryMapper">
<when-type-is class="com.test.sampleapp.CustomPlaceHistoryMapper" />
</replace-with>
But for some reason the replace does not seem to be happening. CustomPlaceHistoryMapper is not getting kicked in and the generated class still uses AbstractPlaceHistoryMapper.
Any thoughts/pointers as to what might be resulting this behavior are much appreciated.
Note: I have also posted this on the GWT group but haven't received an answer so far.
To make the deferred binding work a class must be created with GWT.create(). However, AbstractPlaceHistoryMapper is only used as an extended class. So it will never be created via GWT.create, but always by instantiation the subclass. And therefor deferred binding won't work in this case. If you want a complete different implementation you have to implement a custom PlaceHistoryMapper, and manage the known tokens yourself. This also means you can't use the History annotations either.
As a side note the classnames in your rule should be swapped. But for the end result this doesn't matter, since it won't work in the first place.
It is absolutely possible to have custom history tokens (eg. #mail or #mail/bla instead of only #mail:inbox) using the out-of-the-box Place-related classes that GWT (2.0) provides.
Instead of replacing AbstractPlaceHistoryMapper you could instantiate the default PlaceHistoryMapper passing in it's constructor your implementation of PlaceHistoryMapper<T> or PlaceHistoryMapperWithFactory<T>.
eg.:
final PlaceHistoryHandler placeHistoryHandler = new PlaceHistoryHandler(new CustomHistoryMapper());
You will be able then to map tokens as you wish.
I personally recommend you to use an unique PlaceTokenizer in you mapper custom implementation so that I dont have to have an inner PlaceTokenizer class in each of your Places.
Hope that helps. Feel free to ask any doubts.