In a project i'm working on, we follow the MVP structure but we do not use any particular framework like GTWP. For such situations where theres no code splitting 'out-of-the-box' what are some best practices to adopt in the utilization of this tool? (Where to split the code, other considerations, etc)
I recommend to go through GWT Developer's Guide Code splitting . It talks some best practices.
https://developers.google.com/web-toolkit/doc/latest/DevGuideCodeSplitting
Related
I am thinking about developing a new application using web toolkit. I decided that the best option is going to be to use the Model-View-Presenter Design Pattern. After doing plenty of research, I found two different ways of implementing the skeleton code. (I am still trying to learn MVP and how to best utilize the disjunction between the model and the view)
Here are the two links discussing GWT MVP
https://developers.google.com/web-toolkit/doc/latest/DevGuideMvpActivitiesAndPlaces
https://developers.google.com/web-toolkit/articles/mvp-architecture
I read through and understand all the information in the second link, how you associate presenters with views, and how you have your custom events and such. I really like this because this means that several developers will be able to work on the project I have in mind.
However, the first link, also points out some interesting stuff, mostly using XML and #UiBinder and other things. I feel that those will not be necessary for this particular application but I want to make sure I have not overlooked anything.
Basically - How good of a programming practice is the style the style in the second link (the one with presenters for each view)
Thank you
You should be not be comparing MVPActivitiesAndPlaces and MVP . If browser history management is not your concern use only MVP.
Activities And Places are not mandatory for MVP. They only allow you clean browser history management which integrates nicely with MVP architecture.
UiBinder is not mandatory for MVP. They can be used with MVP.
The MVP design paradigm mostly is driven with Unit testing as main driver and to keep out slow running GWTTestCase out as much as possible.
At the heart of this pattern is the separation of functionality into
components that logically make sense, but in the case of GWT there is
a clear focus on making the view as simple as possible in order to
minimize our reliance on GWTTestCase and reduce the overall time spent
running tests.
I am looking to build a GWT based web application. Being new to GWT, am looking for suites that provide the best GWT widgets (in terms of user experience, variety, styles, etc.), to help build a web app.
I have come across SmartGWT, but looking for other options/suggestions.
Thanks in advance!
I've done apps in both GWT and SmartGWT. My observations, for what it's worth:
SmartGWT has all sorts of cool features, out of the box. It's easy to be seduced by the SmartGWT showcase.
GWT is converging on SmartGWT, and quickly. For instance, the new DataGrid
can stand up against the SmartGWT ListGrid and come away looking good.
In order for GWT to look good though, there has to be real skill in the
developer. SmartGWT can make anyone look good, it seems, but to make
GWT shine takes skill.
Once you have that level of skill, though, there's no looking back.
GWT seems to me to be much more flexible, a consequence of the building-block approach. SmartGWT is more monolithic.
SmartGWT's design has some portability issues. I successfully took a pure GWT app I made and re-worked it (minimal effort) to run nicely in a BlackBerry PlayBook browser. I took a
SmartGWT app I had made at about the same time, and half the widgets
didn't work.
For an enterprise level solution I'm working on, I'm using pure GWT and I don't regret having made that choice.
I would suggest using standard gwt widgets. Simply because,
1)they are best documented,
2)they are highly customizable via css
3)from what I observe they provide the best performance
4)you dont need to learn a whole new framework built on top of another framework
but if you insist on using a framework then I suggest you take a look at this question
My advice to you is to consider your needs. Plain GWT and SmartGWT both are the best supported, so you need not look for more (unless of course both fail in what you want).
Go to their respective showcases and see what they offer and how it fits your requirements.
If gwt satisfies all your UI requirements, my advice is to choose it over SmartGWT. gwt beats SmartGWT in learning curve and documentation anytime. Also its faster(my opinion). If gwt doesn't satisfy your needs and SmartGWT does, then you should consider making the switch.
I have a year experience in smartGWT, when we started our first gwt lessons, they said use the basic gwt features and build own framework otherwise we can encounter errors which may lead to dead-ends. We considered the idea, but for the project (since we already had deadline) decided to look after some extension of gwt. We found smartGWT. The showcase was really convincing. Remember these are widgets, the basic logic of your system is still up to you.
In case if you start using smartGWT: If you don't use JSON but some normal list of java structures prepare to get hard hours/days to get use to datasources, grids, and few other components. Seriously, it had ridiculous problems (for example switching two configuration code line without reason makes work the listgrid), BUT before you drop the entire idea to use it, after a while it starts to work, and it becomes really impressive and comfortable. This is a kind of work "make it once, will work hundreds of times".
In my opinion:
don't start use smartGWT if you want to make a system which is not too complicated.
start use it if you need complicated system with lot of different features, if you don't have the time to develop everything for yourself: many components are ready in smartGWT.
At the moment Iam evaluating java web frameworks. More precisely Iam talking about GWT, JSF2 and apache wicket. One very importent criteria in this evaluation is prototyping.
The prototyping process in my company can be described by the folloing:
The customer can produce GUIs with an easy to use WYSIWYG editor, by drag&drop-ing web components on the corporate predefined website structur. There is also a need for some litte dynamic being like navigation from one frame to another.
So Iam looking for tools. These tools should not only provide nice GUIs but also deliver
some basic code, which can be forwarded to the development. The aim is to avoid missunderstandings between designers and developers as much as possible. More or less the
developers just have to implements the code, but not to implement the optical requirements.
In addition it would be desirable to customize the components thats been used in the WYSIWYG editor. Does anyone know any good tools for the mentioned frameworks (GWT, JSF2, wicket)?
One of the challenges with WYSIWYG tools for UI is that you generally have to pick between rapid prototyping and maintainable code. Even then, as soon as you want to do something that's not supported by the prototyping tool, you can implement it as you would without the prototyping tool, but your round-trip functionality (namely turning your app back into something that can be edited) is broken or crippled unless extra work is done to generate the metadata that the editor needs.
Upgrading between major releases is another issue. Vendors and groups who have developed these tools have a historically spotty record of when they stop supporting older versions, reasonably because of limited resources and sometimes difficult problems with how to track solid innovation happening in the framework itself.
My suggestion instead is to prototype with an RIA prototyping tool like Balsamiq Mockups or use a grid system like 960 Grid to generate rapid prototypes, then use a web development framework that allows your developers to run the code with or without the backend server. Wicket has a tag called that is great for this kind of thing -- web devs can fill a div with stuff that a component should generate, and Wicket devs can wrap the contents of that tag with after they implement it. Both parties can coexist for a long time that way.
Try GWT Designer for GWT.
Introduction
Quick Start Guide
Download
There's nothing like this for Wicket that I know of. The closest you would get to any kind of resource reuse from your customer would be to give them a drag and drop HTML editor - the resulting HTML could then form the basis of Wicket page/panel layout.
if you are planing to use a javascript library, you may use extjs,
http://www.sencha.com/products/js/
they have developed a nice designer
www.sencha.com/products/designer/
there is also a port of ext in GWT
www.sencha.com/products/gwt/
You have to pay for a commercial license if your application isn't open source!
A question for all the GWT gurus out there.
I'm a newbie in GWT and am trying to understand the best practices of coding a GWT application. I have gone through "Large scale application development and MVP" based on Ray Ryan's talk at Google I/O 2009 and it has given me a good starting point. I downloaded the sample source code as well for the Contacts application based on the best practices listed.
The application I'm trying to develop using GWT is a bit bigger (in terms of the modules involved) when compared to the sample "Contacts" application & so I want to split it up into multiple functions.
I have been reading that having a single Entry point in a GWT application is a good idea, and I don't want to dump all the code in one single AppController class & one single RpcService, what would be the best approach in this situation?
How would I go about dispatching the control to multiple controllers? Is there a way to achieve this using some classes in the GWT framework?
For large GWT apps, a framework like GWTP (which is a fork of gwt-presenter and gwt-dispatch) is almost necessary. It provides things like Places for handling location/history, a handy Presenter framework, EventBus, and really simple codesplitting.
If you are developing very big application then split your application into multiple modules.
For client side MVC pattern I suggest PureMVC.
http://puremvc.org/
If you're worried about initial load size and it's possible to load your big app in different chunks, consider Code Splitting
I'm starting work on a smartGWT project in a few days and I'd like to know what kind of experiences you had. To avoid making this a bashing of smartGWT or GWT or a freestyle discussion, I'm going to provide some pointers for the discussion:
Do you feel that the provided widgets are integrated well? Is there any widget you miss in particular?
Have you encountered any problems when designing your application that were caused by the framework?
Is the datasource integration as usefull as the smartClient team claims?
What methods do you use to make your smartGWT application persistent? e.g. How well do Hibernate and smartGWT play with each other?
Feel free to add anything you feel is worth pointing out.
I guess you already have your answers, but I would like to add a few more comments that may affect your decision:
Pros:
SmartGWT is the most compreensive LGPL GWT-based widgetery library you can find. So if you care for GPL pain, this is your thing
Comprehensive Showcase.
Really good performance (just check the Showcase).
Very active community in the forums.
SmartGWT extensions is another important project. For example, it has support for GWT-RPC based communication, which is not possible only with SmartGWT (unless you implement your own integration).
Rapid pace of development from the SmartGWT guys. Just count the number of releases since the SmartGWT project appeared.
Cons:
Besides the Showcase, I sometimes feel the only way to figure out how something works is by asking in the forums. This leads to a spread knowledge base. A community based wiki would be preferable.
Large amount of static files you have to use with your application (the famous 'sc' directory) which might lead to problems if your back-end is in GAE (because of the 1000 files limit).
We used SmartGWT in our last project (duration: 6 months). The following is my personal opinion:
The widgets are really great! The documentation and API is verbose. We would use client-side again.
The server-side integration works, but did not save any development time. Instead we had a lot of problems where we had to find workarounds. Also, because of the new API, no other developer can maintain the project within investing a lot of time to learn the SmartGWT API.
Some Cons:
You have to learn a totally new API instead of using Hibernate and GWT-RPC or REST.
The data integration is done automatically, that is true. But if you need some (also little) changes, you have to write XML mapping files as with Hibernate or JDO. So the benefit is gone.
The forum support is bad: You get an answer to almost every posted question. But that answer often does not help. They ask you things such as “why do you want to do that”. Or they say: “use our tool and do XYZ with it” three times, although again and again I told them this suggestion does not work. After a few answers to a question the final answer is: “you need training, buy our support”.
The commercial support is way to expensive (costs approximately as much as the SmartGWT license).
We will probably not use the server-side integration of SmartGWT again.
You can read all my "lessons learned" with Pros and Cons at my blog:
http://www.kai-waehner.de/blog/2010/12/11/lessons-learned-smartgwt-2-3-component-library-for-google-web-toolkit-gwt/
Best regards,
Kai Wähner
Do you feel that the provided widgets
are integrated well? Is there any
widget you miss in particular?
You could create any missed widgets, there is no single framework that can provide everything you want. The widgets are pretty extendable.
Is the datasource integration as usefull as the smartClient team claims?
The data (JSON/XML) can be provided by servlet services, and they are understood by the
widgets.
What methods do you use to make your smartGWT application persistent? e.g. How well do
Hibernate and smartGWT play with each other?
In the backend servlet services of GWT, you can persist your data in the store by using any persistent layer in Java. Hibernate can be just used as same as normal java app.
Do you feel that the provided widgets are integrated well? Is there any widget you miss in particular?
Yes. The widgets have a consistent API and work well together.
Is the datasource integration as usefull as the smartClient team claims?
This IMO is one of their strongest feature. Once you start using their Datasource API you realize how little code is required to get a fully functional CRUD screen
What methods do you use to make your smartGWT application persistent? e.g. How well do Hibernate and smartGWT play with each other?
Hibernate works out of the box with the SmartGWT EE version. With the LGPL version using Glead works wells
I think SmartGWT has a ton of great widgets, but but but there is a HUGE price.
Create a simple SmartGWT based project and watch how many files get loaded by your page.
That, I think, is totally against the ideals of something like GWT. While SmartGWT may be a pretty good option for people on a deadline, if you want raw performance, stay away from it.
The number of HTTP requests will simply kill your application.
Have you encountered any problems when designing your application that were caused by the framework?
Yes. When I combined Google Eclipse plugin, SmartGWT, GWT 1.6.4, and Wicket the gwt compiler would emit bad javascript. By bad javascript, I mean javascrip that would not work in webkit, or firefox. I was not able to get good javascript until I removed it completely from the Eclipse project and restarted Eclipse. So, this combination would not work and I ended up building the SmartGWT piece separately in another project. The other issue is that the Smart client seems to want control of the whole page in a css sense. So, the integrated SmartGWT module was all messed up, because styles were not isolated properly. Your mileage may vary.
Personally if you use SmartGWT only and for everything then all will most likely be fine, but if you try and mix it, well my results were disastrous. So, I no longer use it.
Just as a counterpoint to the poster above who mentioned troubles with Wicket, the SmartClient forums (forums.smartclient.com) have reports of success integrating SmartGWT with a wide variety of other technologies. This poster's problems sound like 1) a GWT bug causing bad JavaScript and 2) CSS naming conflicts between SmartGWT and Wicket, probably neither framework's fault. All of SmartGWT's style names can be renamed via the skinning system to resolve any such conflict.