I'm trying to learn some basic knowledge of jsp, suppose that I have a project, in this project, after signing in, I have a Main.jsp with a calendar or a dropdown list in it, when selecting a date, I'll change the UI based on the data from database.
I can put all relevant data into request after signing in, and use JSTL in Main.jsp, but if the data is huge, this doesn't sound like a good idea, right?
Back to the old age when there's no JSTL or AJAX, how does jsp developer deal with this? And what is the best practice nowadays?
Thanks.
If you are talking to render about without JSTL or AJAX, the only option i see is to submit/send the form to server and get it back with updated view, but yes it will cost a lot in terms of performance.
I think for your use case:
1) you can get the data from server via AJAX on every update,
2) or, if the data is not customer dependent and is fixed in terms of UI, you can load it lazily in background, and change the view immediately on the user action.
Related
I am in the process of creating a simple application with Spring Mvc and thymeleaf and I am currently thinking of what functionality I want to implement but I don't know exactly how to do it.
Let's say I have a model class Person. Regularly I have a form and a controller where I am passing the new person object and persist it with JPA.
No problem there but what if I want to have a page that I give some of the person basics info and then hit the "next" button and give some additional information. Then hit "next" again, review the data and hit "save"?
You can do it by integrate Spring Webflow in your project.
Webflow is basically extensive part of WebMvc. Webflow has some configuration that, where you have to start and where you should go. If you have 5 page and you would like to all these data will put into database in one process then Webflow will help you. One more advantage is, you can add validation in particular pages and particular means you have five model and all these model will work in one flow.
Read more, https://projects.spring.io/spring-webflow/
I have not used Thymeleaf, but usually this kind of problem can be solved using some of the following methods or something similar:
1.) Save the unfinished data to database using the same schema or some other schema for this (or in session; in general sense, save it somewhere on server side). Problem with this is how to get rid of abandoned data where user has not moved to finish.
2.) Drag the data from page to page with request parameters. If the requests are of type POST then just in POST body, if they are type GET then as query parameters. Problem with this is it's not very clean.
3.) Don't do full page requests. Solve it with some front end solution using Javascript. Depending on the app it might or might not be possible.
4.) Do full page requests but still solve it in front end using local storage or session storage. Similar problems as with keeping the data in server side session.
I am new to spring and JSP. My web application is spring powered, which I run locally in apache tomcat.
In my JSP page I have multiple file-upload inputs and many text input fields.
Every time, when I press any of the upload buttons, a HTTP POST request goes to my controller from where on I may save the image to the database.
But, what I want is:
I will upload the images one by one ( preferably by staying in the page) but won't save them in database and then when I press submit to get the rest of the input text fields data, I commit all the data, including image, texts to the database in one try.
I have heard of scope="session" for my controller(bean) in the dispatcher-servlet.xml ... but I am unsure as to if I upload image to my controller and get back to my JSP form, will the bean keep my already uploaded images?
I think it is hard for me to explain, so please let me know if my question is not clear.
It would be nice if anybody can come up with a suggestion that may help to obtain my goal.
Are you uploading a varying number of images, as in if someone wants to upload only 2 they'll have 2 file fields on the form, or does everyone get 5 fields for example?
To be honest, the whole scheme of incremental upload sounds a bit overcomplicated at this stage. (Unless you have an explicit need to show progress bars on each upload, etc.) What if the user abandons the form after uploading the first image? You'd need a pretty solid mechanism to keep track of the entire visit, keeping it in the session wouldn't help here. Can a user pick up where they left off? If you make the whole thing work with single form submit click first, you can break it out and fine tune the process later. I mention that since you stated you're new to jsp and Spring (what's your experience with web dev otherwise?)
I think the best way is to upload file using ajax control rather than submitting form for each upload and store the file references in session scope variable(attribute). there are lot of libraries have ajax based file uploading like extJS, JQuery, GWT, DWR , whatever ajax library you are using in your web application.
I am setting up a simple CRUD page for my website content and would like to know if codeigniter has any in built functions for displaying confirmation messages.
As I will be giving the user the ability to delete rows from the database I will need a layer of confirmation before they are able to deleted the row.
What is the best method/ suggested way of doing this in codeigniter? I have previously just used javascript, but would like to know if there is another way?
Have you looked into GroceryCRUD? Implementing this might save you some time.
However, your only real options are to use a javascript confirm() dialogue or to direct the user to an intermediary page (another action in your CRUD controller) which provides the user with confirmation options.
If you're aiming to implement the Javascript solution you might wish to consider creating the delete links with javascript too, that way users without Javascript enabled will not be able to delete. This has it's obvious downsides but will prevent users deleting rows without confirming first.
I have a question that i want to add the function to track the click stream of user in my website, How can I achieve this, using ajax tracker or Django-tracker modules?
I have actually wrote a django-clickstream application, I just haven't open sourced it yet, I want to test it out to make sure it works well before releasing it.
Here are the steps you need to do to reproduce what I did, it isn't too hard.
First off you would need to keep track of each visitor for the life of their session or cookie. You can do this using django-visitor or roll your own.
Once you have a visitor you can create a custom middleware that will look at each request and then log what url each visitor visits to a database table. Then all you need to do is create a simple web page where you can view the different click streams by visitor.
One important thing to note is that you will need to setup an exclude filter so that the middleware doesn't pick up any urls that you don't want to track (static, etc), I did this with a simple list of regular expressions that I stored in the settings file. If the url doesn't match one of the regular expressions then log it.
The table will get pretty big real fast if you have a popular website so you will need to create a management command to clean out the old records from your tables.
Django-visitor: https://bitbucket.org/kencochrane/django-visitor
Edit:
Check out Django-clickstream: https://bitbucket.org/kencochrane/django-clickstream
I have 2 entities (for this example) in CRM 2011 - Account and Case. The Account holds all of our clients, the case holds individual work actions for an account. When a case is created one of the input fields is the Account.
What I would like to do is upon the user selecting the Account, execute some javascript to look up the account entity to display some additional information.
So far I have got the javascript working that triggers the onchange event of the Account field, and it correctly gets the selected Account, but I don't know what the next step is.
I'm new to CRM so don't really know if what I'm asking is actually sensible, if there is a better way then please let me know.
Thanks!
For the record, the way you were thinking about doing things would be completely supported, and TechHike's method is supported in CRM 4, not CRM 2011. Steps you would take:
Use CRM 2011's web resources to upload a script file that does what you want.
Use the form editor to make your javascript method from step one fire when the Account field changes on the form
Make a request to CRM's REST endpoint (http://msdn.microsoft.com/en-us/library/gg334767.aspx) to retrieve the details of the account selected
Use the results to populate fields on the form, show a popup with details, etc.
There are plenty of examples of caling the REST endpoint from JavaScript in the SDK (http://msdn.microsoft.com/en-us/library/gg309408.aspx). Good luck!
Matt's post above contains everything you need to know, but you might also find the blog post below useful. It basically describes the same scenario where you have a 1:n relationship (such as Case and Account) and details how you can pull information from a specified lookup (e.g. account), using the REST endpoint (as Matt has already mentioned) and display it on the form.
http://community.dynamics.com/product/crm/crmtechnical/b/crminthefield/archive/2011/02/07/showing-related-information-in-a-crm-2011-form.aspx
The blog post includes a link to download a CRM2011 solution already built to give you something to look at how they've achieved this (useful if you're new to CRM2011).
There are two ways to do this, and you may be best to do them both in parallel:
on the Account > Case relationship edit the Mappings. When a user goes to an Account and uses the left navigation to look at Cases (or a grid of Cases on the form) then hits "Add New Case" they are creating a Case from inside the "context" of the Account. You can copy any fields you want to from the Account to the Case record at this point - the Mappings define what field from the Account are copied to which target field on the Case. This will always be the most robust, easiest way to do it but relies on the user starting in the right place.
on the Case for you could also add an onChange script to the Parent Customer lookup to fetch the data from the parent record. I think Stephen's link is probably the best way to do this as it does not copy the fields but allows the user to see them anyway, which is better database design (from a purist standpoint) and means the user always sees current info about the Account rather than possibly out of date stuff. Alternatively if you actually need to copy some fields (maybe the customer's normal SLA say) so that you can use these in other such as scripts or workflows on the Case then have a look at this article: Disabling the selection of contacts for opportunities all the way
Although this is about a slightly different topic, the script there fetches the Account details of the parent Contact - you want to fetch values from a parent (llokup) field so the approach is the same, just different in the detail
There are various ways to do this but I would recommend doing it the supported way, without javascript. This may not be as pretty but it is likely much easier. The scenario would be to add a left navigation link to the case entity that when clicked will update the content area to show the details of the account.
To add a link to the left navigation you will need to configure the isv.config file to have an extra link for the case entity.
Here's an example:
http://support.sfusion.com/kb/hosted-microsoft-crm-4/how-do-i-modify-the-isv-config-file-in-microsoft-crm-4/
You can also lookup isv.config customizations in the SDK, found here:
http://www.microsoft.com/downloads/en/details.aspx?FamilyID=82e632a7-faf9-41e0-8ec1-a2662aae9dfb&displaylang=en
Next you will need to create a custom aspx page in the ISV folder of the web server. This page will display all the information about the account that you want to show the user when the left navigation link is clicked. The ISV.config as an xml property that allows you to pass all the context params to your page on the querystring. Make sure when you create the link to turn on this attribute.
Now the only tricky part is that in the page you will need to use the CRM web service to display all the account details that you interested in showing the user. I won't do into details on this. You can find great tutorials on the web or in the SDK if you haven't done this before.