So I'm working on a form that makes use of database grids, I'm having an issue where I need to auto-default a field based upon the amount and GST fields. This will always auto-default my field for the user until the point where they manually change my field, at which point it obviously will not do anymore defaulting for that record.
Any ideas on how I can achieve the recognition of a manually modified field in Delphi? Please note I'm not talking about the manual modification of a record so the following code is not applicable to my situation (unless you can somehow find a way to use it).
Much appreciated!
Populate the value in the field when the amount or GST changes, and then calculate whatever the field is you want to auto-default. Allow the user to change it, and don't react to that change unless the user modifies the amount or GST again. You can use the TField.OnChange event (on the amount and GST fields) to do so.
Related
I'm writing a room booking system in .net Core 2.0
I have StartTime and EndTime stored as DateTime variables, but the built-in HTML datetime field is clunky and rather user-unfriendly, so I want the values to display on the page as a date field and a time field.
But I'm wondering what the best way of implementing this is. Should I:
create some readonly variables within the model (can I do this without creating database fields?)
create the separate form fields (with jQuery datepicker) and then use JavaScript to write the values of the inputs to hidden fields which store the full DateTime?
(NB I haven't chosen to change the database fields because it is conceivable that a booking might run past midnight. The JavaScript would assume that an early hours endtime is the next day. )
First and foremost, use DateTimeOffset instead of DateTime for your database-backed date/time properties. Whether you end up storing the values in UTC or local time, as long as you have the timezone, you can get to whatever other locale you need. Trust me, this will be invaluable in the long run.
As far as editing goes, make your inputs datetime-local types. This isn't actually supported by any browser, but it at least carries more semantic value and who knows, maybe one day browsers will finally get off their collective hind-quarters and do something with it. Breaking it out into separate date and time fields is tempting, so that you can take advantage of built-in browser controls, but it's clunky and prone to error. Use a JavaScript library that provides a good date and time control to progressively enhance the input instead. My favorite at the moment is air-datepicker. It's lightweight, supports all sorts of scenarios and configuration options, and it's localized.
I'm using Rails 4, and also Twitter Bootstrap.
I'd like to select the date with a date picker, but have a separately visible component for selecting the hour and minutes.
I've had a look at smalot bootstrap-datetimepicker https://github.com/smalot/bootstrap-datetimepicker , but looking at the Demo Page, they don't demonstrate any ability to show date and time separately. You have to choose date, and then later on choose time, which doesn't feel very intuitive.
I've also looked at Eonasdan bootstrap-datetimepicker https://github.com/Eonasdan/bootstrap-datetimepicker , but the time picking for it, even in inline mode, is not intuitive - will people know they can just click on the hour value to change it?
I'm thinking of just using a date picker for picking the date, and selecting the hour and minute myself, but it kind of feels wrong handing off part of a datetime to a gem/library and handling the rest of it myself.
I came across Separate date and time form fields in Rails , which is asking about this kind of problem, but it's a question from September 2010.
How do I select the date with a date picker, but have simple and immediately visible selection of time?
First, unless you find a plugin that does what you want off the rack, then yes, it's up to you to handle it, and yes, it feels kinda wrong - depending on how you do it.
Not sure what you had in mind, but the way it feels "the most wrong" is if your form has a single "date time" field under the hood, and you use javascript to botch together the date from the plugin and the time from your own setup, and store them in your datetime field. The nice thing about this is your rails app just gets a single datetime field and knows exactly what to do with it.
Here's how I'd approach it:
Keeping in mind that forms don't necessarily have to map 1-to-1 with your models, I'd split it in the controller layer, and conceptually think of "a form with two fields: date, and time", and then in your controller (or a form object, which is probably better for this situation) you'd stitch the date and time together, before saving them to your model. This approach means you can have separate validation on each field, which is probably also what you want (because I'd assume it's possible for users to input a valid date, but an invalid time or vica versa).
In terms of handling the date with a plugin and the time yourself, that's now fine - they're two completely separate fields from the perspective of your form, so there's nothing dirty about it. It just means you need the extra logic in your controller layer to split the datetime when you display the form, and merge the date and time back into one when you save the form.
Edit: if you haven't heard of form objects, check out https://github.com/apotonick/reform and http://railscasts.com/episodes/416-form-objects
For some files the content_create_at field is set to a date that is later than the content_modified_at field. How can that be? Is this simply because these are the dates set by the client?
I have read http://developers.box.com/content-times/.
John is right. There is (likely) some client that is setting one or the other field. In general we recommend setting both the fields when you set them, so you don't provide confusing dates to other systems.
When choosing 'Add' in CRUD, how best to generate a list of choices to pick from a dropdown?
For U/update - just display what's there...
The field contents starts with a letter, followed by five numeric digits:{A-I,K-N,Z}#####
Each letter has a different 'max' value for the numeric part.
So when adding a new record, I'd like to offer a listbox with one of each letter and that letter's highest numeric value + 10.
So, if the max 'A' as A00120, and max 'B' B00030 (etc) the listbox would have A00130 and B00040.. etc
Save the user having to figure out which is 'next' when generating a new record.
? Thanks,
Mark
This time I'll not be able to come up with ready to use solution, but I must say - everything is possible with ATK4. You just have to customize and extend it to fit your needs :)
Speaking about your question above - I guess you have to split it in multiple parts.
First part is about how to show select box on Create and readonly or disabled field on Update. I guess you can make some custom Form field or pin some action to existing Form Field hook. Not sure exactly what's better in this case.
Second one is about data structure. I believe that this field actually should be 2 fields in DB and maybe (only maybe) merged together in ATK model with addExpression() just for user interface needs to display these 2 fields as one field easily in UI. Maybe such concatenated field will be useful also for searching, but definitely not as only one field stored in DB. Imagine how hard it'll be for DB engine to find max value if such field. Store it like type = letter, num = number and then search like SELECT max(num)+10 FROM t WHERE type='A'
Finally Third part is about how to generate this next number. I read your question 3 times and came to conclusion that actually you don't have to show this +10 numeric value in UI at all if it's hardly predefined anyway. Actually that'll not work correctly if this will be multi-user system which I guess it will. Instead just show simple select box with letters {A-I,K-N,Z} and calculate this next value exactly before inserting data in DB. That can be done using models insert hook. This will be much more appropriate solution and will be better for UI and also more stable because calculated in model not incorrectly in UI part.
So I'm messing around with a new project in Delphi 2009 and the default components that can be dropped onto a form for accessing data consist of a SQLConnection, DataSource and SQLQuery. If I add a simple select to the query component, say:
select name from customers
and then drop a DBComboBox on the form and link it up with the DataSource I get a single record in the combo box. After using Google for half and hour to figure out what I was doing wrong it looks like you have to manually add some code to your project which loops through the dataset and adds all the records to the drop down box. Something like:
while not SQLQuery.eof do
begin
DBComboBox.items.add(SQLQuery.fieldbyname('name').asstring);
SQLQuery.next;
end;
And that actually sort of works, but then you get a list in the drop down which you can't actually select anything from. Regardless of the result though I'm wondering why would you even use a DBComboBox if you have to manually add the result of your query to it? Seems to me that if it doesn't automatically populate the db combo box with the result of the query then we might as well be using a non-data-aware component like tcombobox.
I guess what I'm asking is why does it work this way? Isn't the purpose of data aware drag-and-drop controls to minimize the amount of actual written code and speed development? Is there a method that I'm missing that is supposed to make this easier?
A TDBComboBox doesn't get its list of values from the database; it gets its current value from the database. Link it to a field in your dataset, and when you change the active record, the combo box's current value will change. Change the combo box's current value, and the corresponding field's value will change.
If you want to get the list of values from the database as well, then use a TDBLookupComboBox.
This is all covered in the help:
Using TDBListBox and TDBComboBox
Displaying and Editing Data in Lookup List and Combo Boxes
Defining a Lookup List Column
I think you want the TDBLookupComboBox because that allows you to lookup from a list of items where the list comes from a dataset.
In the TDBComboBox, the list is just a TStrings manually filled with data.
--jeroen
DbCombox is a dbaware version of the standard combobox component.