cocoa + what ui element should i use? - cocoa

I am developing an app which has a text field box. so when i am entering text, it should search the database and give me suggestions just like google search. like if i have entered letter 'a', it should have a box like thing below text field with all names starting with letter 'a'. then if i have entered letter 'b', it should resize the box and give names that start with 'ab' and so on.
I was planning to use a table view below the text field which reloads itself as and when new thing is entered into text field. but i dont know how to resize the table view depending on number of suggestions. So is there any other ui element which suits this kind of situations?
Also how do i detect a new alphabet or number entered into text field so that i can filter out suggestions like is there any such notification? what i mean to say is say i entered letter 'a' so now the string value of text field is 'a' and now i entered say 'b'. so now the string value changed to 'ab'. how do i detect this? i think textDidChange notification will do this for me.
Thanks

You can use an NSComboBox for auto-completing lists like you describe. NSComboBox is a subclass of NSControl so you can use the -controlTextDidChange: delegate method to detect changes in the text that the user types. Make sure you set the control to "continuous" in Interface Builder or call [comboBox setContinuous:YES].

If, for whatever reason, you find that a combo box is inappropriate for your situation, you can implement the list of completions as a child window of the control's window, with a headerless table view in it. Then you would programmatically resize that window as the number of possible completions changes.

Related

Keyboard Extension - Find out if user did Copy/Cut/Select

In Keyboard Extension, in UIInputViewController, I can get notified through textDidChange(textInput: UITextInput) of any change, and use self.textDocumentProxy.documentContextBefore/AfterInput to get current text.
Problem arise when user 'select text'. The 'before' and 'after' "sees" only the part before and after selection.
Is there any way to know if user touched any of the Copy-Cut-Select in a textField (given - we don't have access to that field from Keyboard Extension)?
Something like:
if(self.textDocumentProxy.someProperty == UIDocumentProxyTextCut)
Or any other way to know which of the UITextField action (Copy/Cut/Select) did the user took?
I think we can not find out if user touched on Copy/Cut/Paste menu
Because a custom keyboard can draw only within the primary view of its
UIInputViewController object, it cannot select text. Text selection is
under the control of the app that is using the keyboard. If that app
provides an editing menu interface (such as for Cut, Copy, and Paste),
the keyboard has no access to it. A custom keyboard cannot offer
inline autocorrection controls near the insertion point.
Source: https://developer.apple.com/library/ios/documentation/General/Conceptual/ExtensibilityPG/Keyboard.html
P/s:
I saw self.textDocumentProxy.documentContextAfterInput is always NIL. Who know why?
How can we know where the cursor is to provide suggestion for user?

(Mac OS X, Cocoa) How to make drag-and-droppable placeholder elements in an input text field?

I'm writing a Cocoa app where I would like the user to be able to put together a template string using placeholders. (For example, an (artist) placeholder would be filled in by the artist of the song currently playing in iTunes, etc.) I've seen apps that do something like this where each possible placeholder term is displayed in a blue "lozenge," and the user can drag and drop these "lozenges" into an input text field to construct a string, optionally entering some custom text of their own (e.g. separating (artist) and (title) "lozenges" with a hyphen).
Does anyone know if there is any sample code anywhere that will help me implement something like this?
I'm talking about something like this: (this comes from the "Hazel" app where, in a Hazel rule, you can rename a file based on a template pattern you specify)
NSTokenField is focused in the above pic (has the blue ring around it). Each "token" (your lozenges) is an auto-recognized string for the token field. As rdelmar comments above, read up on NSTokenField and you'll be most of the way there.
The "source" of tokens is likely a rounded-edged NSBox containing lined-up borderless, no-background NSTokenFields with one token each. That'll give you easy drag-and-drop as well as easy alignment.
if you need to customize the l&f of the individual tokens, you need to implement your own stuff: NSTextView with NSTextAttachment which have NSTextAttachmentCells... Its painful and a lot of code but actually not that hard
The NSTokenAttachment cell only has lots of private l&f options :(

NSTextView / NSScrollView - A few questions to help me understand it's proper usage

I have created a "notes" field designed to hold multiple paragraphs of text which I would like to store in a custom object. Originally, I just used an NSTextField as a temporary solution, but this does not allow me to scroll or have multiple paragraphs of text...
In IB I have placed a NSTextView (which seems to be wrapped inside an NSScrollView.) Upon execution of my program, seems to allow me to enter text in multiple paragraphs, scroll, etc. In short it LOOKS to be exactly what I want would like it to be. So far so good.
Now, I need to retrieve the data from this field and store it in my custom object. This is where I'm getting a bit lost within the developer documentation...
My goals are fairly straight forward:
Allow users to type away in the box.
Store the contents of the box into a variable (array, etc.) in my custom object when the user moves to another field, leaving the notes field.
Display the users stored text in the text box next time the record is viewed.
Second, is there a simple way to retrieve and store the data into a "notes" variable in my custom object (such as an NSString object? I would think having multiple would exclude an NSString object as an option here, but maybe I'm wrong) or am I getting into a more complex area here (such as having to store it in an array of NSString objects, etc.)?
Any help would be appreciated!
You can get the data using -string, defined by NSText (e.g. NSString *savedString = [aTextView string])
Your save code can be put in your NSTextDelegate (read, delegate of the NSTextView, because it's the immediate superclass), in – textDidEndEditing: which will be called, well, when editing is finished (e.g. when the user clicks outside the view) or one of the other methods.
Then to reload the saved string if you emptied the text view or something, use [textView setString:savedString] before editing begins.
NSTextDelegate documentation: here.
I'm not sure what you mena when you say "store the contents of the box into a variable (array, etc.) Are you hoping for an array of custom notes? Text views store a string of data, so the easiest way of storing its value is using one string; if you need an array of notes you'd have to split the string value into different paragraphs, which shouldn't be too hard.

Choosing the order that text fields cycle when tab is pressed

I have several text fields and would like to set a particular order in which they would cycle when the tab key is pressed. Currently, it starts at a text field with becomeFirstResponder and then goes on in the default order which xcode put. Can I somehow bypass that order and force the text fields to cycle in a particular order? Like linking the last one of the cycle back to the first one.
Thanks for the help.
Connect the initialFirstResponder outlet of your window to the first text field, then build a chain by connecting the nextKeyView outlet of that text field to the text field that should come next (and so on).
That's called the key view loop.

Filtering text in NSTableView

I have an NSTableView in which I need to be able to intercept keyboard events within an editable cell and replace the cell with strings. For example, press "a" and have the "a" intercepted and the value "Alpha" assigned when the table reloads. The actual situation is a bit more complex in that I'm also handling HID devices, but that's a whole other story. Suffice it to say, I just want to be able to go into edit mode and stop the keyboard-generated values from being displayed.
The latter part of this (displaying "Alpha") is easy, but I can't figure out the first part of the problem. If I subclass the table and make it first responder, I can receive the keyDown: event, but once the user double-clicks on a cell and starts typing, this goes silent.
Since none of the other NSTableView components (NSCell, NSTextFieldCell, etc) derive from NSResponder, I'm assuming there is an NSTextField buried in there somewhere.
So, what's the best way to filter text once the user goes into cell edit mode?
As always happens: after working on this for eight hours, reading all the docs five times, and then resorting to the net, I find the answer five minutes later:
- (BOOL)textShouldBeginEditing:(NSText *)textObject.
Sorry to consume bandwidth.

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