I am developing a web app using Oracle ADF. I have a bounded task flow. In that I have a search page like below.
I have created the above two forms using view object data controls.
Searching is performing well. But my problem is when I go some where else in my application using menus provided left side and come back to the search page , the page is not getting refreshed. I am getting a search page that contains old search results. At this point of time if I am trying to make any changes am getting some error called "Another user with this id already modifed data ....". After this error my app is not running. Means what ever am trying to do its showing the same error.
So I need to make this: "When ever the user come to this form, He should get fresh form. It should not contain old search results.
Please help me. How do I achieve this.
Thank you.
There are 2 ways of doing it:
1) Set your task flow as ISOLATED, from Task Flow Overview tab -> Behaviour -> Share Data Control with calling task flow -> unchecked (or isolated, if you are using JDev 12c)
This will ensure you always start FRESH when accessing the page, but it will potentially create a performance overhead because entire View Object cache will be recreated (requeried) on page load. Nevertheless, it is the quickest solution.
2) You may create a default Method Call Activity in your task flow from where you may call a AM's custom method that resets the view criteria. The method will be placed on application module's implementation class and it may look like this:
public void initTaskFlow() {
this.getViewObject1().executeEmptyRowSet();
}
This will clean the result data. If you want to reset the querying parameters as well, you can use this example:
http://www.jobinesh.com/2011/04/programmatically-resetting-and-search.html
When you made any changes to any viewObject then excute this viewObject to match entity state and viewState , i think excuting viewObject will solve your issue
Ashish
Related
How can I invalidate a single item when working with useInfiniteQuery?
Here is an example that demonstrates what I am trying to accomplish.
Let`s say I have a list of members and each member has a follow button. When I press on to follow button, there is a separate call to the server to mark that the given user is following another user. After this, I have to invalidate the entire infinite query to reflect the state of following for a single member. That means I might have a lot of users loaded in infinite query and I need to re-fetch all the items that were already loaded just to reflect the change for one item.
I know I can change the value in queryClient.setQueryData when follow fetch returns success but without following this with invalidation and fetch of a member, I am basically going out of sync with the server and relying on local data.
Any possible ways to address this issue?
Here is a reference UI photo just in case if it will be helpful.
I think it is not currently possible because react-query has no normalized caching and no underlying schema. So one entry in a list (doesn't matter if it's infinite or not) does not correspond to a detail query in any way.
If you prefix the query-keys with the same string, you can utilize the partial query key matching to invalidate in one go:
['users', 'all']
['users', 1]
['users', 2]
queryClient.invalidateQueries(['users]) will invalidate all three queries.
But yes, it will refetch the whole list, and if you don't want to manually set with setQueryData, I don't see any other way currently.
If you return the whole detail data for one user from your mutation, I don't see why setting it with setQueryData would get you out-of-sync with the backend though. We are doing this a lot :)
I have a WPF application that uses entity framework. I am going to be implementing a repository pattern to make interactions with EF simple and more testable. Multiple clients can use this application and connect to the same database and do CRUD operations. I am trying to think of a way to synchronize clients repositories when one makes a change to the database. Could anyone give me some direction on how one would solve this type of issue, and some possible patterns that would be beneficial for this type of problem?
I would be very open to any information/books on how to keep clients synchronized, and even be alerted of things other clients are doing(The only thing I could think of was having a server process running that passes messages around). Thank you
The easiest way by far to keep every client UI up to date is just to simply refresh the data every so often. If it's really that important, you can set a DispatcherTimer to tick every minute when you can get the latest data that is being displayed.
Clearly, I'm not suggesting that you refresh an item that is being edited, but if you get the fresh data, you can certainly compare collections with what's being displayed currently. Rather than just replacing the old collection items with the new, you can be more user friendly and just add the new ones, remove the deleted ones and update the newer ones.
You could even detect whether an item being currently edited has been saved by another user since the current user opened it and alert them to the fact. So rather than concentrating on some system to track all data changes, you should put your effort into being able to detect changes between two sets of data and then seamlessly integrating it into the current UI state.
UPDATE >>>
There is absolutely no benefit from holding a complete set of data in your application (or repository). In fact, you may well find that it adds detrimental effects, due to the extra RAM requirements. If you are polling data every few minutes, then it will always be up to date anyway.
So rather than asking for all of the data all of the time, just ask for what the user wants to see (dependant on which view they are currently in) and update it every now and then. I do this by simply fetching the same data that the view requires when it is first opened. I wrote some methods that compare every property of every item with their older counterparts in the UI and switch old for new.
Think of the Equals method... You could do something like this:
public override bool Equals(Release otherRelease)
{
return base.Equals(otherRelease) && Title == otherRelease.Title &&
Artist.Equals(otherRelease.Artist) && Artists.Equals(otherRelease.Artists);
}
(Don't actually use the Equals method though, or you'll run into problems later). And then something like this:
if (!oldRelease.Equals(newRelease)) oldRelease.UpdatePropertyValues(newRelease);
And/Or this:
if (!oldReleases.Contains(newRelease) oldReleases.Add(newRelease);
I'm guessing that you get the picture now.
We are porting a D6 application to XE3.
In D6 I inherited a complex code which used shared datasets and datasources everywhere.
This worked well in D6.
After we could run the XE3 version, we experienced that lookup combo boxes changed.
On dropdown they reset the other dropdown's keyvalues (everywhere in the program)!
If two dropdowns use on dataset, and if I click on the first to down it, and select, on down the second keyvalue changed to NULL; and reverse - if I click on the second, the first's keyvalue change to NULL...
This is global in this program, so I need to find fast solution.
May somebody have any information about this "bug" (or "feature"? :-) ), or have a solution in his/her hand?
Thanks for any answer!
This is intentional. Take a look at the implemention of TCustomDBLookupComboBox.ListLinkDataChanged; in Vcl.DBCtrls. You will find the comment:
{ Fix for Defect# 204311, Non-bound control should clear when list datasource changes }
Solution: put your datasets on a data module. Instantiate that for every form, so every form works with a separate instance of the dataset. Make sure you set the name of the data module to an empty string after instantiation, or the Delphi streaming system will still use the first correctly named instance when hooking up the form's datasources with the datasets.
When the data module(s) are in the form's uses clause (interface or implementation doesn't matter) the IDE will still offer you their components through the Object Inspector.
You will want to put the database connection on a different data module that you only instantiate once (possibly automatically).
I have a custom object with a master-detail to opportunity. Is there a way to determine if the user has read or read/write access when querying this custom object?
To clarify my needs, I'm looking for a way to render my page (non-visualforce) with a clear distinction between records they have only read access to and records in which they may edit.
The user will have the same access to that as they have to the opportunity. The Profile object exposes permissions but it doesn't appear to allow you to find out about CRUD settings for objects.
Are you creating an integration piece or working with Visualforce? If you're using Visualforce the interface will respect security controls automatically, hiding data they're not allowed to see and making fields read only when using <apex:inputField> if they do not have permission to write to the field.
** Edit **
Maybe somebody will have a better solution, but how about trying to update the records you query, storing whether each was a success or failure, and then using that to control the interface? Bit of a hack, if I find anything else I'll be sure to update.
** Edit 25/01/2012 **
Have just come across this: http://www.salesforce.com/us/developer/docs/api/index_Left.htm#StartTopic=Content/sforce_api_objects_userrecordaccess.htm?SearchType=Stem
Pretty sure that'll give you exactly what you need!
This might contain answer to your question http://salesforceblogger.blogspot.com/2012/04/query-user-access-level-in-apex.html
There is an UserRecordAccess table which is exposed with API 24.0 with which u can easily check for access instead of banging ur head with share object.
I don't know of a way to query to find out the level of access however if your apex class uses the With Sharing keyword it will respect sharing on the object thus when you attempt to update the data you'll get a DML exception which you could catch.
If you're not using With Sharing then apex doesn't respect the Sharing model and technically the user will be able to update the data even if they don't have access.
As pointed out by LaceySnr if you're using visualforce the <apex:inputfield> element will display read-only automatically to the user if they only have ReadOnly Access.
I'm trying to figure out a user friendly way to pass messages to users from my Apex code. I have a trigger which fires after insert/update of a lead, which then filters the list of updates and triggers a #future method which pushes the lead data out to an external web service and updates the converted account with some of the returned values.
I'd like to do the following (where X, Y and Z are any number of leads from 1 to 50)
notify the user converting the leads that leads X, Y and Z will be exported (I'll know this during the trigger execution).
notify the user whether the export succeeded or failed (which will be known for each of X, Y and Z when the #future method runs).
What is the recommended way to pass this information back to the user? I'd prefer not to use email (as this would trigger one email per record, which is pretty spammy and unpleasant). Is there another way to inject notification messages into a page? I've tried ApexPages.addMessage() but it doesn't seem to do anything for me (no error, but no notice either).
addMessage() works with both Visualforce pages and standard pages when there's a current page active, so using this in the trigger should work fine if the user is firing the action from a button / VF page. Using this won't work from your #future method however because it runs asynchronously in the background.
Maybe the best solution would be to use a custom message object, which has a list of fields modified, when, and has a lookup to the appropriate user (or uses them as the owner). You could then create a simple VF page and controller which when viewed queries for records in that object related to the current user and provides an option to delete them (you could automatically delete them after pulling them from the DB but you run the risk of the user not actually noticing a message). You can then take this page and use it as part of a dashboard component, so anytime the user is viewing their Home page they could see a list of notifications.
Finally another option might be making use of Chatter, pumping the messages to the user via that which will then also show up in digest emails etc..