I always update the design of the form in the active method of the data source. Updating design means enabling or disabling buttons based on the form data source cursor. However, I face the situation in which the user receive the error of simultaneously working that means should refresh the form. when user use CTRL+SHift+F5 as it is asked in the error message, the design will not be updated even the data is updated. Because active method is not called in this case.
I investigate other methods and understand that form data source refresh method is called most of the time but not when form is initialized. It means that when the form is going to open the button is not enabled or disabled based on the first record which is cursor.
The question is that what is the best place for updating design of the form based on the record?
Is using form data source refresh method common to update design ?
I think there is not enough information to provide a good solution for this error but basically what I'd do is to debug it setting a breakpoint in the aosValidateUpdate (or similar) to check which code is updating the row twice.
Another possible fix is to call reRead before this error happens.
Related
I am new to android and java and working on an app that has a few remaining problems that I haven't resolved yet.
I have a main activity that is a viewPager, with each page being a fragment. If the 4 fragments 3 are extended from ListFragments and one from PreferencesFragment.
The ListFragments have CursorAdapters to get data to and from SQLite databases through providers.
I am able to get data into the database, insert, modify and query the data correctly and fill the list views ok.
My preference setting are to choose different ways of viewing the data in the database.
Not knowing how to do this, I have implemented a process where I modify the cursorLoader query to the provider with a number of different choices of the "WHERE" clause. I have worked out the logic for the preferences as they exist now, implemented the code but had some difficulty finding what to try to trigger the refresh of the ListView.
Since the "dataset" hasn't really changed, no trigger can come from there, plus that would just use the same cursor as it currently exists to run the query again and return the same results (or be smart enough to know that it doesn't need to run).
On Stack Overflow I did find a couple of references to a similar implementation that suggested reStarting the cursor loader, which would then on the reStart read the current values in the stored Preferences file, create a now modified WHERE clause that will show the sub-set of data as specified in the preference settings.
In testing the app now, even with the reStart of the cursorLoader, the ListView isn't getting refreshed.
The only time I can get it to work right is restarting the app. If I stop the app and restart it, the new values are used and the ListView presents as the preferences dictate.
In looking through Stack Overflow and the Android site, I did find another set of APIs that might have been a more natural fit for what I am trying to do, namely the Filter APIs.
First question then would be, did I go in the wrong direction on how to control the "filtered" view of the datbase. Is filtering a better approach and a recommended way of
doing what I am trying to do?
Second question would be related to the fragment lifecycle of my ListFragments to achieve this CursorLoader update.
Thanks for any input on the topic.
-Dan
Found my problem here.
Two things, the way I am trying filtering is working and from what I have seen in the
Android development site, a reference there indicated that the filtering capability is
already implemented in the CursorAdapter, CursorLoader classes I am using.
When my preference settings changed, I did a reStart of the cursorLoader, but had restarted the wrong one.
Problem solved. Any input on is there a better way would be appreciated.
Regards, Dan
First - I am having a hard time formulating this question, so please bear with me, and ask for clarification and I'll try to provide as much as I can. I am just starting to learn meteor, so be patient please.
I have several inputs that save immediately as people type on them. (with a slight 300 ms delay to not overload database).
Basically, on "keyup" it goes and saves. All that works fine. However, I'd like to add a visual indicator (say a green checkmark, or a tiny "saved") when the database actually stores what they typed.
Graphically:
[___________________]
[Typed something_____] (saved)
[___________________]
I am not sure how to go about this, but it's something common, that plenty of you have already done. If I didn't care about the database feedback, I'd just use JQuery, target a class beside the input and make the checkmark or word visible after a keyup, or add it to the DOM. Fairly straight forward.The only when I am sure it has been stored in Mongodb part confuses me.
Any help would be gladly appreciated.
Thank you
Addendum with code:
Template.dibs.events({
'keyup input.name': _.throttle(function(event) {
Dibs.update(this._id, {$set: {name: event.target.value}});
$(':focus + .glyphicon-ok').css('opacity',1);
}, 300),
Can you explain where/how you would add the code? (For spinner, or the words).
Coming from JQuery I did something that I know is not the right way. This is in the client portion (I know just demo code, and it's not secure) but I wanted to know the best way leveraging meteor to do it. I already have checkmarks stating it was saved in the page, but they are all hidden, this code just makes them visible on keyup for the field.
I read through the article, and didn't quite see how I'd go about doing the intermediate step (spinner or the like) then the finalized checkmark after code is saved. I've also being going through the new 1.0 tutorial (which is great) but I'm still missing the visual indicators. It's great that meteor updates the UI if it fails in the server to reflect that it didn't save, since I am assuming success, I don't think that tapping into the Meteor.Error makes sense. Should there not be a Meteor.Success or equivalent?
Again, I apologize for the long message, I'm trying to wrap my head around this, because the technology looks very promising
Welcome to Meteor! Meteor was in fact designed (among other things) to handle just this type of situation, via a mechanism called Latency Compensation. You can read more about it at Meteor.methods.
Calling a method on the server requires a round-trip over the network. It would be really frustrating if users had to wait a whole second to see their comment show up due to this delay. That's why Meteor has a feature called method stubs. If you define a method on the client with the same name as a server method, Meteor will run it to attempt to predict the outcome of the server method. When the code on the server actually finishes, the prediction generated on the client will be replaced with the actual outcome of the server method.
You can use Latency Compensation by defining a Meteor method to save the input text to the database, with a client stub that displays a spinner instead of "saved", and "saved" when its callback is called successfully.
Alternatively, you can call the update method on the collection directly, and add a callback on the client, which will be called with (error, numberOfDocsUpdated) after the server method returns.
Read more on when to use Meteor methods and when to use client-side operations.
As Dan has said, the Latency Comp takes care of needing to do this. Another way of doing this is in a template event. You can set a session variable on keyup with the contents of the text field and in the helper, set a flag that will render the checkmark when the session variable and current user input matches.
Lets try this explanation again...
I'm new to polymer (and getting back into web dev after a relatively long absence), and I'm wondering what the recommended approach might be to more closely manage object state while employing 2 way databinding. I am currently consuming rest API (json) objects. My question is if polymer keeps a copy of the original object before initiating updates to the bound object's properties/attributes...so one might be able to easily undo the changes? While allowing 2 way databinding to work its magic is often desired, there are cases where I'd like to prevent / delay changes to the object / DOM until the user approves the changes (say via the paper-dialog component for instance). I suppose one could make a temporary copy of the object and bind fields to that version, and then only persist the changes back to the source object upon user approval. In any case, I'd be interested to hear thoughts and see an example or two of recommended approaches (especially if I am off-track with my ideas!)
I suppose one could make a temporary copy of the object and bind
fields to that version, and then only persist the changes back to the
source object upon user approval
This.
Consider that view-models are essentially different from pure data-models (sometimes called business-data). Frequently, the differences are irrelevant and one can use them interchangeably. However, be aware of scenarios where the view-model is distinct (uncommitted user edits are a good example).
The notion of a field editor that requires approval from the user is purely UI/View oriented. Whatever data is managed in that modality is purely in the domain of the view, and fetches/commits to the business-data should be discrete.
I'm currently working on a reasonably complicated data input form, based around ASP.NET Web Forms. After the form has been completed, we'd like to offer a chance for the user to review their input before actually submitting the form (as well as going back to make changes to their data if requried).
Due to the large number of fields, I wanted to use a FormView control due to it's automatic databinding ability, removing a lot of tedious code, however there doesn't seem to be a simple way to offer this functionality.
At the moment, my current approach uses an ObjectDataSource to bind all the form fields. I've created two 'modes' of operation on the data source; one mode temporarily saves the object to the user Session (allowing retrieval again later for read-only/edit modes - this facilitates the review/modification functionality), while the second mode actually does the database insertion.
While this seems reasonably robust at this point, it still feels quite dirty to me. I know I could use a Wizard/Multiview type approach, but then you lose out on the niceties of automatic databinding (I believe?). I'm sure this is a fairly common problem, so how is this typically done in a Web Form environment?
Thanks!
The project I am currently work on uses a custom wizard setup (not the asp.net 2.0 wizards). It comprises of the several steps your wizard may require, and when you go from one step to the next, the code saves the values into a final step (a read-only review). When the user gets to that last step, they can go back to the step that needs to be updated. When happy, the user submits the wizard, and the data is saved to the db. It is basically a series of panels that have their visibility toggled.
You should be able to still use the ObjectDataSource for each of the editable fields, having the panel or mutliview being visible or not shouldn't affect the binding. When you go from one panel to the next, you can update a read-only step (like I said before) while keeping the editable controls bound to the ObjectDataSource. When you go back to any steps that need to be modified, you are still bound, so when you make any changes and click submit or whatever the button is, it should use the ObjectDataSource.
Anyone else have any other ideas?
I've got a wizard control that databound controls on each step. I can't databind them all at once because they are dependent on the previous step. So, essentially what I've got at each step is a save to the database of the previous step, and an initialization of the current step.
Are there any recommendations as to how best to organize my code? It works, but it's not very readable, and extremely brittle.
EDIT: I should add that I've seen most of the wizard control tutorials out there, but none of them seem to address what I'm trying to do. In particular, the need to save and retrieve data between steps, and how to keep it from retrieving that same data again if the step is revisited.
What you've done sounds reasonable.. Can you be more specific about the problem you are having?
One thing about the wizard control, as your workflow gets more and more complex I think the coupling between your workflow state and the wizard SelectedViewIndex becomes problematic. For this reason I eventually separate them. I will usually use a state/statemachine pattern, where the current workflow state is used to determine the appropriate wizard view index (but not vice-versa).
If you're looking for examples on how to implement a state machine, I have a test app out there that walks through dialogs like a wizard control, except using javascript. Check out http://main(dot)test.wishpot.com/WaveDataCollection.Frank/, after you get to the page CollectSamples.aspx, go ahead and view source, then start reviewing at the GotoState function.
State machines are plumbed a bit different in C#, the main difference being the state object is an abstract class with a fixed number of event handlers, which each state inheriting from that class implementing each handler (some perhaps throwing an exception). With javascript we don't need the abstract state class... Also, doing this serverside, you're going to need to be able to map from a state ID stored in your database to a state class.