I have an NSTextField with NSDateFormatter. The formatter accepts 'mm/dd/yy'.
Is it possible to complete the date automatically? So the user can type 'mm' and the formatter completes the current month and year.
Any particular reason you don't want to use an NSDatePicker? (It does require 10.4 and later, but that's less of an issue these days)...
No.
You are going to need some logic that detects when "mm" is present in the text field and then get the current date from NSDate and then pass that into the date formatter to get the string and then display it in the text field.
You could also investigate the various delegate methods available to NSTextField. If my memory serves me right, there is didBeginEditing (which is inherited from NSControlTextEditingDelegate, check that class reference). However, I'm not sure if that fires every time you input a new character...though it may. In which case it'd be a case of assigning a delegate that checks the NSText string and does a little comparison.
Related
I have a listbox with 2 columns (say "from time" and "to time"). I want to filter user input by 24 hour format only i.e. no other key should be allowed to press except 24 hour time format (i.e 00:00 to 24:00) in the cell. I tried with this: &"0-2"#&"0-3"#:& "0-5"#&"0-9"# it works well but it didn't allow to put something 19:22 or the value after 13:59 in the cell value as I haven't passed other optional value for that 24 hour time format. In regex, it's a bit easy to achieve this ('/^([01][0-9]|2[0-3]):([0-5][0-9])$/') but not sure how this can be done in the 4d database listbox cell field.
Any help would be appreciated. Thanks.
I suggest you make the list box columns text and manage the display and UI yourself if you require fine control over the input values.
The Time string method will convert a time value for you:
$timeStr:=Time string(Current time) // $timeStr = "07:23:45"
The input filters are not RegEx and will not give you the kind of fine control you need. They will let you filter unwanted characters (anything besides numbers for instance). Try this for the Entry Filter on the column
!0&9##:##:##
The result will be a text string of the numbers entered. Write a method to take the input string, parse the elements, validate them, update the data source and then return a properly formatted string for display. I would use the On data change form event as the trigger for running the method.
$h:=Num(Substring($inputStr;1;2))
$m:=Num(Substring($inputStr;3;2))
$s:=Num(Substring($inputStr;5;2))
Recent versions of 4D manage time values as seconds since midnight which is why you may get a longint value instead of a 'time' value sometimes. And depending on which version you are using and the type of listbox (collection, entity selection, array, etc.) you may not even have a 'time' type option for the list box column which can be confusing. Given all that it's just easier to stringify the value and work with that.
For example, what do you want to do if a user enters "33:45:00"? If you want to reject the "33" at the outset you can do this by evaluating each character as it is typed. The On After Keystroke form event lets you run your evaluation method after each change in the field and the Get edited text command allows you to see what the user is entering. https://doc.4d.com/4Dv18R3/4D/18-R3/Get-edited-text.301-4901376.en.html
To convert a string (or longint) into a time value use the Time method:
$timeVar:=Time($timeStr)
4D is a typed language and has had a time type since the beginning. However with the addition of ORDA some UI objects no longer support the time type (collection and entity selection list boxes, for example) and use a longint type instead. This can be confusing if you are working with an existing app or older code but attempting to use the newer tools. Be sure to look over
https://developer.4d.com/docs/en/Concepts/time.html
and
https://doc.4d.com/4Dv18/4D/18/Date-and-Time.201-4504355.en.html
You may not need to get so involved in the input. It depends on the nature of the UI and the data. Time and date is tricky in just about every platform.
I have a very standard binding set up in android on a UITextView
local:MvxBind="Text Quantity"
Where Quantity is an int property.
If I enter 123 say, that gets assigned and the setter is called. As I delete that text, 123 -> 12 -> 1 -> empty string, the setter is called for each number but not for the empty string infact the following exception occurs:
MvxBind:Error: 48.84 SetValue failed with exception - FormatException: Input string was not in the correct format
Is there a way of automatically converting the empty string value to 0 in the binding? Will I need a value converter for this? Is this in fact a bug?
Thanks in advance.
This area has been discussed recently in https://github.com/slodge/MvvmCross/issues/350 with some nullable additions in https://github.com/slodge/MvvmCross/issues/373 - people are welcome to contribute their opinions (and/or code) there.
The current 'status quo' is that MvvmCross will parse and represent valid decimal numbers. However, if the number isn't valid - eg if it's string.Empty or a set of non-numeric characters - then MvvmCross won't interpret these as zero (should "" be zero? should "asdf" be zero? should "123.456.7" be zero? should "1234asd" be zero? perhaps all of these should actually be NaN?).
If people need specific behaviour then it's easy for them to implement this behaviour - e.g. using a custom control (subclassed UITextField), using a value converter, using a custom binding (or overriding the default binding), using a string property on the viewModel, etc.
My personal opinion is that this topic really comes under the Validation heading. In general, MvvmCross doesn't provide many hooks for Validation at present. It's been proposed for a long time - https://github.com/slodge/MvvmCross/issues/133 - but no-one has shown much interest. There are some simple validation samples in the WithErrors demo within https://github.com/slodge/MvvmCross-Tutorials/tree/master/ApiExamples. Within the apps I've written we've generally written and sub-classed UI controls to help reduce the need for validation - and in general we've tried to avoid the need for as much text input as we can (users don't like seem to like using keypads on phones)
The ActionView::Helpers::FormOptionsHelper provides the time_zone_options_for_select to get a list of options for a select control that includes all of the timezones with their UTC offset. The problem I'm having is how to get it to display the correct offset for when daylight savings time is in effect?
For instance U.S. Mountain time is usually -7 UTC but during the summer it's effectively -6 UTC. Is there a way to have that list correctly reflect that?
TL;DR
The time zone data you are receiving is "correct" because ActiveSupport::TimeZone and TZInfo::Timezone instances do not make assumptions about the current date, and therefore applying DST to them doesn't make "sense" in the context of the responsibility of those objects.
You notice the problem because the default model for time_zone_options_for_select, ActiveSupport::TimeZone, unfortunately returns the offset string when calling #to_s, which, if the location is currently is observing DST, will be incorrect. There is no way to fix the string values generated in the options, or even remove the offset from them.
If this isn't acceptable you'll need to skip on using time_zone_options_for_select, and use options_for_select instead, and generate the options yourself.
Some investigation
time_zone_options_for_select uses ::ActiveSupport::TimeZone as the default model parameter, so passing it in manually will not change your results. In order to construct options for a select box, that method will construct an array of tuples in the format of [time_zone.to_s, time_zone.name], for the purpose of passing it to the more generic options_for_select method. time_zone, in this case, is an instance of ::ActiveSupport::TimeZone.
The important factor here is that this time zone instance object is, conceptually, completely unrelated/divorced from the idea of "the current date". The definition of a time zone (strictly speaking) has nothing to do with the current date. We can confirm this "not using DST" issue like so:
::ActiveSupport::TimeZone.all.find { |tz| tz.name == "Adelaide" }.utc_offset
=> 34200 # 9 hours and 30 minutes, in seconds
Adelaide's non-DST time zone is ACST (Australian Central Standard Time) which is GMT+9.5. Currently (as in the time of writing), Adelaide is in DST which means they are on ACDT (Australian Central Daylight Time), which is GMT+10.5.
::ActiveSupport::TimeZone.all.find { |tz| tz.name == "Adelaide" }.now.utc_offset
=> 37800 # 10 hours and 30 minutes, in seconds
The crucial difference here is essentially what I've outlined above - the ActiveSupport::TimeZone instance is just not concerned with the current date. The class itself is a convenience wrapper around a TZInfo::DataTimezone instance, which has similar opinions on the current date - none.
If you noticed, in the second code snippet above, we called #now on the time zone object before calling #utc_offset. This returns an ActiveSupport::TimeWithZone instance, which includes information about the time zone, as well as the current date - and therefore we get an offset which reflects the fact that the current date should include the DST offset.
So, the only problem here is that including the UTC offset string in the return value of #to_s on ActiveSupport::TimeZone instances is sort of misleading in this instance. It's included because it's the "base" UTC offset for that time zone.
Resources:
Rails 6.1 time_zone_options_for_select implementation
Related GitHub issue, rails/rails#7297
Related GitHub pull request, rails/rails#22243
I had similar problem but ended up using this
time_zone_select('time_zone', TZInfo::Timezone.us_zones,
:default => "America/Los_Angeles",
:model => TZInfo::Timezone
Did you find a better solution?
CodeIgniter stores timezones for its date class in
system/language/english/date_lang.php
I would like to change the strings in this file so that
$lang['UM12'] = '(UTC -12:00) Baker/Howland Island';
$lang['UM11'] = '(UTC -11:00) Samoa Time Zone, Niue';
would instead be
$lang['-12:00'] = '(UTC -12:00) Baker/Howland Island';
$lang['-11:00'] = '(UTC -11:00) Samoa Time Zone, Niue';
Is this possible at all?
Any change I make to the UM__ portion of one line makes it show as a blank on the dropdown. The remaining (unchanged) lines appear OK.
I have also tried to clone this file to application/language/english/ with similar bad results.
Any insights on this?
It looks like this would require hacks to the date_helper.php file which I am not willing to do.
Instead, the date class in CI has the timezones() function which allows you to convert from, for example, UM5 to -5. In that case one can wrap this function around the U__ value coming from the view/dropdown -- and then save it to DB as -5 or some other INT.
Since I want to show the user their selected timezone on that same dropdown, I am forced to have DB fields for the U__ and INT timezone formats. As far as I know, there is no CI function to convert from -5 to UM5.
So, for the user, I pull the U__ format into the view to autopopulate the dropdown.
For timezone conversions and such, I use the INT format.
How can I modify the NSDatePickerElementFlags for the NSDatePicker in row templates for NSDate properties returned by [NSPredicateRowEditorTemplate templatesWithAttributeKeyPaths:inEntityDescription:]? I would like the NSDatePicker to show hrs:minutes as well as the date.
Update
I've added an answer below, gleaned from the cocoa-dev list.
You can probably grok through the templateViews of the returned row templates to set this property.
Per Peter Ammon, on cocoa-dev, and as Ben notes, the easiest way is to modify the date picker in -templateViews directly:
[[[template templateViews] objectAtIndex:2] setDatePickerElements:...]
According to Peter, the order of elements in -templateViews is guaranteed to be constant.