User input: input boxes

Input Required


Last time around we looked at how to use message boxes to send the user informative messages and get simple yes/no input from the user. If you need information such as a quantity, part number, or a name; an input box may be more suitable to the task at hand. Similar to a message box, an input box is a predefined input form provided by the host environment (there is a version provided by the NXOpen API and a version provided by Windows) which we can invoke with a function call. The input box does have its limitations; multiple inputs would be better handled by a custom user form, and the input box won't win any awards for style or usability. That said, the input box does have its uses, even if only to make the programmer's life a bit easier during the prototyping and testing stage.

The NXOpen API supplies a few different methods to get user input, let's take a look at getting a string input. The .GetInputString method has three overloaded versions, you can pass it one, two, or three string arguments which will be interpreted as the prompt, title text, and initial text respectively. A short example is below:

Option Strict Off
Imports System
Imports NXOpen
Imports NXOpenUI
 
Module Module1
 
    Sub Main()
 
        Dim theSession As Session = Session.GetSession()
        Dim workPart As Part = theSession.Parts.Work
        Dim theUISession As UI = UI.GetUI
        Dim answer As String = ""
 
		'input box: prompt only
		answer = NXInputBox.GetInputString("prompt only")
 
		'input box: prompt and title
		answer = NXInputBox.GetInputString("prompt", "title bar caption")
 
		'input box: prompt, title, and initial text
        answer = NXInputBox.GetInputString("prompt", "title bar caption", "initial text")
		'echo the input
        MsgBox("answer: """ & answer & """")
 
 
    End Sub
 
 
    Public Function GetUnloadOption(ByVal dummy As String) As Integer
 
        'Unloads the image when the NX session terminates
        GetUnloadOption = NXOpen.Session.LibraryUnloadOption.AtTermination
 
    End Function
 
End Module

As you can see from the example, the NX input box shows the NX icon in the top left corner but otherwise looks like a generic window. Other than a few text strings, you have no control over the style, location, or functionality of the form. Given the single purpose and spartan design of the input box, the user is very limited in their interactions with it. The user may enter a value or not, then press OK or Cancel (ok, the user could also wait around for the input box to make the next move, but they would be in for a very long wait). The first item of interest to the programmer is: what button did the user press? If the user presses cancel, an empty string, "", is returned. When OK is pressed, the input from the user is returned. User input can take on two basic forms, either: 1) a string value, or 2) an empty string, "". Wait a minute, both OK and Cancel can return an empty string? Unfortunately, yes. If there is no input in the box (either the user presses OK before entering a string and no initial text was supplied, or the user deletes the initial text) an empty string will be returned when the user presses OK. So how do we differentiate between a user pressing cancel to get out of the program and one that accidentally pressed OK before entering input? As of this writing, we can only read the user's input, not the user's mind and intentions, but using the initial text option will help reduce the number of "false empty strings". If there is a commonly used response to the input you require, pass that as the initial text. The initial text will all be selected when the input box is shown; as soon as the user starts typing, the new input will overwrite the initial text. In other words, usability of initial text is pretty good, the user does not need to delete the default response before typing in a new one.

In the following code we take advantage of the input text to differentiate between the user pressing cancel or the user absent-mindedly pressing OK before entering input. Let's assume there is no obvious default choice to give the user, so for the default text we'll use a single space character. Unless you were looking for it, you probably wouldn't even notice it was there. We'll use a Do loop to continue prompting for input as long as the user enters invalid input (in this example, invalid input is any number of space characters) and presses OK. Within the loop, we check for the empty string, which indicates the user pressed cancel, and exit the journal when found.

Option Strict Off
Imports System
Imports NXOpen
Imports NXOpenUI
 
Module Module1
 
    Sub Main()
 
        Dim theSession As Session = Session.GetSession()
        Dim workPart As Part = theSession.Parts.Work
        Dim theUISession As UI = UI.GetUI
        Dim answer As String = ""
 
        'loop until there is valid input
        Do
            answer = NXInputBox.GetInputString("Enter your name", "Name?", " ")
            'if cancel is pressed, exit sub
            If answer = "" Then Exit Sub
        Loop Until answer.Trim.Length > 0
 
        theUISession.NXMessageBox.Show("Greetings", NXMessageBox.DialogType.Information, "Hello, " & answer)
 
 
    End Sub
 
 
    Public Function GetUnloadOption(ByVal dummy As String) As Integer
 
        'Unloads the image when the NX session terminates
        GetUnloadOption = NXOpen.Session.LibraryUnloadOption.AtTermination
 
    End Function
 
End Module

 

The final NXInput box sample uses .NET's TryParse methods to validate numerical input. This example uses a simple version of TryParse, there is an overloaded version that offers more control over what input gets converted. This gets into culture specific formatting and is beyond the scope of this introductory article, but if you are interested, a good place to start is MSDN.

 

Option Strict Off
Imports System
Imports NXOpen
Imports NXOpenUI
 
Module Module1
 
    Sub Main()
 
        Dim theSession As Session = Session.GetSession()
        Dim workPart As Part = theSession.Parts.Work
        Dim theUISession As UI = UI.GetUI
        Dim answer As String = ""
        Dim myInt As Integer
        Dim myNumber As Double
 
        answer = NXInputBox.GetInputString("prompt", "title bar caption", "initial text")
        MsgBox("answer: """ & answer & """")
 
        'loop until there is valid input
        Do
            answer = NXInputBox.GetInputString("Enter your name", "Name?", " ")
            'if cancel is pressed, exit sub
            If answer = "" Then Exit Sub
        Loop Until answer.Trim.Length > 0
 
        theUISession.NXMessageBox.Show("Greetings", NXMessageBox.DialogType.Information, "Hello, " & answer)
 
        'loop until there is valid input
        Do
            answer = NXInputBox.GetInputString("Enter an integer", "Number of copies?", " ")
            'if cancel is pressed, exit sub
            If answer = "" Then Exit Sub
        Loop Until Integer.TryParse(answer, myInt)
 
        theUISession.NXMessageBox.Show("Valid input", NXMessageBox.DialogType.Information, "The input was successfully parsed as: " & myInt.ToString)
 
 
        'loop until there is valid input
        Do
            answer = NXInputBox.GetInputString("Enter a number", "Length of line?", " ")
            'if cancel is pressed, exit sub
            If answer = "" Then Exit Sub
        Loop Until Double.TryParse(answer, myNumber)
 
        theUISession.NXMessageBox.Show("Valid input", NXMessageBox.DialogType.Information, "The input was successfully parsed as: " & myNumber.ToString)
 
    End Sub
 
 
    Public Function GetUnloadOption(ByVal dummy As String) As Integer
 
        'Unloads the image when the NX session terminates
        GetUnloadOption = NXOpen.Session.LibraryUnloadOption.AtTermination
 
    End Function
 
End Module

 

Here is some code that uses the .NET input box instead of the NX one. The look of the input box is largely the same (there may be differences based on the version of Windows you have installed), the main difference is no NX icon appears on the input box. Take note of the added Imports System.Windows.Forms statement at the beginning of the code, this allows you to call the InputBox function directly; otherwise each call would look something like: System.Windows.Forms.InputBox(<parameters>). Control freaks take note: the second input box call uses optional parameters to specify where on the screen the input box should appear. The coordinates specified designate where the top left corner of the input box will be drawn. I've also included an example of how to determine the primary screen's resolution, so if you do want to specify the input box location you can keep it within bounds. Other than those minor differences, the look, feel, and response of the input boxes is the same; the one you choose will be based on personal preference.

 

Option Strict Off
Imports System
Imports System.Windows.Forms
Imports NXOpen
Imports NXOpenUI
 
Module Module2
 
    Sub Main()
 
        Dim theSession As Session = Session.GetSession()
        Dim workPart As Part = theSession.Parts.Work
        Dim theUISession As UI = UI.GetUI
        Dim answer As String = ""
 
        'plain .NET input box
        answer = InputBox("prompt", "title bar caption", "initial text")
        MsgBox("answer: """ & answer & """")
 
        Dim intX As Integer = Screen.PrimaryScreen.Bounds.Width
        Dim intY As Integer = Screen.PrimaryScreen.Bounds.Height
        answer = InputBox("This input box has been positioned at: (50,10)", "Input box with defined position", " ", 50, 10)
 
    End Sub
 
 
    Public Function GetUnloadOption(ByVal dummy As String) As Integer
 
        'Unloads the image when the NX session terminates
        GetUnloadOption = NXOpen.Session.LibraryUnloadOption.AtTermination
 
    End Function
 
End Module

 

Summary

The input box can be used to get simple input from the user, or it can be used by the programmer to test different input before the user input form is created. Either the NX or .NET input box functions can be used, both are similar in look and features.

 

 

Comments

please explain to me, If you have a sub main after this code, how do you pass the entered information to another part of your program. let me explain a little better, I have a program that writes all assembly file names to text file, then it reads each line of the text file and makes it the displayed part, then i execute a grip program to some stuff in each file, the problem i have is i want to pass the user input from the begining of the code to the last area of the code to be passed to the grip program as strings. the program is broke down into 3 sub mains please help

I'm not quite sure I understand. You have 3 Sub Main subroutines? does this mean you have 3 journals and you need to pass information between them?

If you can email your code to info@nxjournaling.com (or a simplified version that demonstrates the problem), I'd be glad to take a look.

Just wondering if you know whether NX could remember what you entered for input from the last time the script was launched.

For instance, I like how after I put in a chamfer size the next time I use the chamfer function the last size I used is displayed. I believe that if the user interface is built using the NX/Open User Interface Styler I would have the same functionality available. This is nice if, for instance, I would like to create a script that will add attributes and values to populate the fields of a title block. This way the designer value will always be in the input box when the script is launched.

If I could do this with a .NET or NX form that would save my company the cost of purchasing an expensive developer license for the NX Interface Styler.

Any thoughts or suggestions on how to do this would be appreciated.

You can save input such as this in the user's registry; .NET provides a SaveSetting and GetSetting function to make this easy. Reference: http://msdn.microsoft.com/en-us/library/3kz7fyks(v=vs.71).aspx
http://msdn.microsoft.com/en-us/library/kb0c3wb9(v=vs.71).aspx

You can see a simple example of this in the export pdf journal in the OutputPath() function.

http://www.nxjournaling.com/?q=content/exporting-drawings-pdf-files-using-nx-journal

Hello,
Is it possible to entering info and then hitting enter button instead of clicking ok?

Yes, if you use the .net input box function.

could you give an example please

Run the .net input box example above (the last section of code). Enter something into the input box and press "enter", the effect is the same as if you had pressed OK.

How to make the characters uppercase when you enter text in the NXInputBox? In below examples I want to that during enter text the characters will be in uppercase. Is it possible?

            answer = NXInputBox.GetInputString("Enter your name", "Name?", " ")

Thanks
Marcin

Unfortunately, the NXOpen API does not give you that much control over the NX input box. However, if you create your own "input box" style dialog using windows forms (assuming you are using Windows), you can easily convert the input to upper case. See this page:
https://support.microsoft.com/en-us/kb/818363

I'm not sure, but you might be able to do something similar with the NX UI styler (or block styler).

Hi,
How to add some predefined strings list in input box,???
so that user can select some repeated input strings.

-[]-

There is no such option in the input box. If you would like to present a list of choices to the user, you will need to construct your own custom dialog box. This can be done with the UI styler (if you have the appropriate license) or with a Windows form (assuming that you are working on a Windows OS and working with C++ or a .net language).