Local Variable or Write VISA Icon?

Suppose that you have a control in front panel to set amplitude of generator. If you do a loop in which you desire to increse every loop the amplitude it's better use a local variable of control in front panel or Icon WRITE of VISA to do this? What is the better solution?
Message Edited by Michelle1892773 on 02-23-2010 04:47 PM
Solved!
Go to Solution.

Writing to the local variable in your code will do absolutely nothing in setting the instrument.

Similar Messages

Data Acquisition - using local variables to write data to a file

Hello,
I am running a Data Acquisition vi (currently in LabVIEW 7.1 but soon to be updated to 8.2) that collects ~100 parameters of data from several sources contained in a while loop. The current configuration (which I did not write) uses very few subVIs and writes to ~100 local variables to store each parameter. It then reads all the local variables and builds an array of all the strings, converts then to a spreadsheet string, then uses the write characters to file function to append to a datafile. I am trying to clean things up and have came up with subVIs to collect the data from the following sources:
8 serial port sources collecting btwn 8 and 20 parameters each
~15 thermocouple readings
~10 analog inputs
~20 parameters read off an ARINC 429 bus.
I have come up with a subVI to read each of the sources and have placed the subVIs in the while loop. Each subVI outputs the data that it collects in array or cluster form. I was wondering how best to write each parameter to a CSV file at between 1 and 10 Hz. Should I write each subVI output to a LV and then read them off as was done before (the difference being that I have reduced the # of LVs to ~10 vs >100?
I should add that precise timing is not that important, so if all the subVIs are not collecting simultaneously (which I understand that they won't be), it does not really matter.
Thanks.

Hi jilla,
jilla wrote:
What I think that you are saying is to turn the outputs of the 4 subVIs into inputs of a 5th subVI that writes to the data file. Correct?
Yes. It may sound like a fine-point, but I beileve it's better to create a VI specifically for formatting data - in your example, 4 arrays IN, a single string OUT. Then write the string to file as a seperate operation. GUI-displayed data can go through a similar transformation, the four arrays wired to a subVI which builds output-structures specifically for display. It's a beginner's mistake to put lots of individual controls and indicators on the screen when groups of them are naturally related (in an object-oriented sense.) Use clusters to group related controls - this will keep the diagram much cleaner.
One more question: at what point (either # of data points or frequency of data collection) does it become necessary to use queues? Thanks.
Well, there's not really a clearly definable "point". I'd say if your update-rate climbs above 100Hz, or you witness poor program or system performance, then it's time. The scenario you've described is a fairly simple acquire/display&log loop - and simple is good. Then-again people can't see/react-to updates faster than about 10Hz - so it doesn't make sense to sacrifice performance - if performance becomes an issue.
Re: queues: Queues are sometimes used to buffer data that's "produced" in one place and "consumed" in another.
Here, if/when logging data, you're logging with every DAQ. I wouldn't recommend using a queue to transport data from a "DAQ loop" to a "Logging-loop" - those functions can be in the same loop. Should/could a queue be used to get data from a "DAQ loop" to update the GUI at a lower frequency? Sure, but a Notifier might be a better choice. Further, in the (simple?) program you've described, you might use a case structure (True/False) to only update FP indicators every "X" iterations - a simple solution that doesn't require Queues or Notifiers.
Cheers!
"Inside every large program is a small program struggling to get out." (attributed to Tony Hoare)

Labview local variables not always renamed

Hello,
I might be missing something, but it seems that sometimes the local variables in my VIs are not always updated when I rename the Front Panel control associated with it.
I have an example where I right click on the terminal of a control named "RxConfigTest", create local variable. The local variable that gets created is named with the old name "RxConfig1".
Have you ever seen that behavior? I'm using LV 7.1.1.
Thank you,
Mathieu

Hi,
Thanks for the response, but I was actually displaying the label. I know that this sounds like a newbie question, but I'm not.
I noticed that by closing and re-openning my VI after the rename, the variables were updated. It looks like a refresh that was not done. Even the local variable in the block diagram was not resized to the new text of the variable name.
I'll try to grab a screen shot if it happens again.

How can I put the contents of an array into a set of write local variable clusters?

I have a set of controls that a user fills in. The controls are clustered by rows, then combined into a 1D array, then written to a file. When I read the file, I want to feed the array back into the clusters with write local variables. Is there a simple way to handle the numerous local variable clusters so I can stuff the array back into them?
Is there a better way to handle the whole issue of storing and recovering the information?
The rows are steps in a procedure, and each row (cluster) contains numerical as well as string controls.

There are many ways of doing this
You may convert all your data to strings and save as an ascii file (you have to pay attention to the file format, so you can read it properly.
Or you can use the configuration vi's, it may work in your case.
or you may use an invoke node to get all controls of the vi's, save it, then read it, without worrying about any format. I have attached a vi that uses this method.
Attachments:
Temp.vi ‏52 KB

How many ways to read and write a local variable in a called VI?

Ciao!
I'm producing my first TestStand sequence. It is called "FirstAttempt" and it is made by a single step which calls a VI. One of the first dilemmas i encountered realizing this sequence is how to read and write a local variable (created going in Variables -> Locals ('FirstAttempt') -> <right click to insert local>) in the called VI.
The first way (the only one i tried) is to create a control and an indicator on the VI front panel, connect them to their respective terminals in the connector pane and then specify (going in Step Settings -> Module) that these connectors (shown in the Parameter Name column) are linked to the local variable (selected in the Value column).
The second way (not tried) consists in using TestStand API: create a Sequence Context reference on the VI front panel, link it to a property node in the block diagram, select the property "Locals" and extract from this the local variable name and value which, i think, can be readable and writable.
So...
Are the shown ways correct?
Are there other ways?
Knowing that a "local" variable can be considered "global" within the whole sequence, is there the possibility to simply create a reference to the local variable and use the reference in the called VI block diagram in order to save space in the connector pane (if using method 1) or in the block diagram (if using method 2)?
Thanks!
Message Edited by aRCo on 09-17-2009 05:09 AM

Hi,
Before TestStand 3 you would use the second way you quoted as its the only way.
But now you would use the first way you quoted. You may still what to pass the SequenceContext if you were going to use the TestStand API. For TestStand 3.x and above you would use this way as the first chose. (Personnelly, I would not pass the SequenceContext into a VI if I know it was never going to be used in that VI.)
Not sure I understand your final comment, maybe you are liking it to passing the reference of a control to a subVI so that the control can be updated from within the subVI.
If this is the case and you had a situation where you had a step that was running in parallel with the rest of the steps in the sequence either as a separate thread or execution and were dependent on the contents of the local variable changing from that parallel running step, then you would have to use the API SetVal method to change the local.
Hope this is clear.
Regards
Ray Farmer
Regards
Ray Farmer

Are the read and write operations atomic for an array in a local variable.

Hi,
I would like to know when you access an array in a local variable, is it an atomic operation?
Thanks,
Mat

Thanks for the comments. I agree with you. However, I my case, race conditions and synchronization are not issues. Therefore, the only thing that matters to me is that the write and read operation of the array must be atomic. I know that I can implement that with a LV2 style global but I want to avoid it if possible.
If writing and reading to an array are atomic operations then I can simply use local or global variables.
All I need to know is: Is reading or writing an array in a local variable an atomic operation?
Thanks,
Mat

Local variable in report writer

how to declare local variable in report writer?

HI Oscar,
what is "local" for you? Local in the report?
Did you check the documentation?
My result in SAP Help Portal is:
[Variables|http://help.sap.com/saphelp_nw04s/helpdata/en/fc/eb3034358411d1829f0000e829fbfe/frameset.htm]
Regards, Boris

Write VISA - escribir una variable continuamente

Hola a todos,
he diseñado una función de PID en labview y ésta me saca una variable de salida que la debo mandar al Write VISA para que escriba en el puerto serie continuamente, ya que la variable se va modificando todo el rato sin parar. Mi duda es como hacerlo porque lo he intentado de mil formas y me estoy desesperando. Nose si esto será posible de todas formas.
Gracias por vuestra respuesta de antemano!

Adjunte su archivo VI y snapshot

How to solve error using local variables?

I've created a sequence with a local variable.
But when I execute it, an error occurs since the first step (before the step where I manipulate the local variable).
The error code is something like:
Error in Evaluation. Syntax expression. Column [0-0]
It's interesting because it seems that once I've executed my sequence for the first time I can't create any other sequence where this error doesn't appear.

Pparo,
The problem does not occur under TS 1.0.3 on my system. However, I think we can get to the bottom of this.
When at a breakpoint in your sequence, if I type the expression "Locals.nls == 15-" in the TestStand watch window, I will get the message
Evaluation Failed: Syntax error in expression (Column 18-18)
I believe that this is the same type of error that you have encountered. Correct me if I am wrong.
The numbers after the word "Column" indicate where the error has occurred in the expression. In your case the error occurs at the beginning of an expression. The question still remains as to in which expression is error occurring.
Are you seeing this error reported in the watch window? If so, then you have typed the expression in the watch window.
If I copy the bad expression above into a the expression of a Statement step I get a run-time error of
An error occurred in the 'Statement' step of the 'MainSequence' sequence in 'Sequence File1'.
The post-expression for the step 'Statement' could not be evaluated.
Syntax error in expression.
Error Code: -17322
From what you report, the error appears to be located in your watch expression. When I executed your sequence with a breakpoint on the first step, I added the watch expression by selected the Context tab, expanding the Sequence Context tree view until I could see the nls variable, and then I dragged nls from the tree view to the watch window. This created the watch expression of Locals.nls. I also created the same watch expression by right clicking in the watch window, selecting Add Watch from the context menu, and selecting (or typing) Locals.nls. The expressions all evaluated to 24 without error.
This process has NOTHING to do with creating local variables. You asked if you are creating variables properly. There are only 2 ways to create variables in TestStand 1.0.3, neither of which you have described. The most common method is to select the Locals tab after opening your sequence (not during execution), right click in the right pane and add the variable of your choice. It seems like you did this correctly based on the sequence file you sent. The other method of creating variables is to do so programmatically. However, this is beyond the scope of this answer.
You ask a question about "the best way to create three constants in LabVIEW and pass them to a LabVIEW VI that is a step?" This implies to me that you want to create the strings within a VI called by one sequence step, and then use them in another VI called by a different sequence step. I would recommend taking a look at the example AccessingPropertiesAndVariables.seq that ships with TestStand. The first 3 VIs write values back to step properties, but could just as easily write them back to local variables. The 4th VI writes a file reference back to a TS local variable. The 5th and 6th step get the file reference from the TS local variable. You want to do something similar to the 4th and 5th VI, however, you want to send 3 strings to local TS variables, and then get them in the following VI. This will require using "TestStand - Set Property Value (String).vi" and "TestStand - Get Property Value (String).vi" which can be found in the TestStand function palette in LabVIEW. After reviewing this example you can then ask additional question. I recommend posting the question on a different thread since it is unrelated to your original question about the syntax error.

Equivalent of "C static local" variable?

Hi!
I am trying to write a sub-VI that has multiple call modes
(init, do1, do2) and needs to remember some variables set in the
'init' call. When I try the straightforward way of just placing
indicators as temporary variables on the front panel, these seem
to reset to the default values every time the VI is called.
Is there any equivalent of the static local variables used in C?
Or do I have to use GLOBAL variables?
Rudolf

There are several solutions:
1. Global variables.
You can create global variable for each of your temorary variables. This is easy to do but I think it's not very convivient way to pass data.
2. One Global variable.
If you have many temporary variables you can organize them into cluster and create only one global variable for this cluster. Then you have to read and write this cluster in your SubVI every time you change any of your temporary variables.
3. Pass data to/from your SubVI.
If you look at the most of LV VIs you will see that very often they have some practically identical input and output nodes. For example "AI Start.vi" has " task ID in' and "task ID out" nodes. You can make the same thing. Let your subVI reads and writes some cluster of your tempora
ry variables through its input and output nodes. So you will have the access to this variables in any place ofyour main VI. Also you can change and create your own clusters of temp variables in your main VI. And also you will get the ability to pass these data to your subVI using local variables or shift registers or sequence locals in your main VI
I think that the last way is the most useful.
Good luck.
Oleg Chutko.

Using local variables to "clean up" diagram

I have attached a photo with red circles indicating my use of local variables to "clean up" a block diagram. Would I run into any issues doing this? Can I leave this task and error unwired?
-Sarah
Solved!
Go to Solution.

I see some possibly really bad race conditions with your VISA Resources. For instance, if Task Out 3 is empty (by default), it is likely that the local to read will happen before the local to write. What this will turn into is you loosing your VISA Reference in the shift register. Use wires. Locals very rarely clean up your diagram.
There are only two ways to tell somebody thanks: Kudos and Marked Solutions

Shall I use global or local variables for my program?

Hello,
1) I am using 2 while loops in parallele. One 50 ms timed and the other one 1000 ms. The 50 ms one gets data from a sensor. I want to display that data every 1000ms in the 1000 ms loop. I have used global variables to do that. Should I better use local variables?
2) This question deals with the VI I have attached
a) Shall I initialise the " Quitter programme " global variable in the main VI aswell ? Or is what I have done enough?
b)
I want the sequence to continue ( finishes the last sequence and goes back to the first one without any delay if possible ) until the user presses Quit. I am concerned about the " wait until " icon of the exterior main while loop ( set to be 250 ms at the moment ). This time, 250 ms, is the time it takes between the end of the last sequence and the beginning of the first sequence? Is that right? Once u start the first sequence, the while loop doesn’t do anything until the end of the last sequence ( my 3 sequences can take several minutes ) ?
Hope I am clear… lol
Don’t hesitate to ask any questions if not clear enough
thanks a lot,
David
Attachments:
Example1.zip ‏28 KB

Bonjour Marc. You will definitely have a race condition because you are writing to the global in a parallel loop. You could click the stop button in the quitter program, then before it is read in the main loop, the lower loop writes a false to it, and your click is lost. Why do you want a separate quitter program? You may have a good reason but it isn't clear here. I would not use globals or locals for this, just put your stop button on the main vi. You already have one, so why do you want another one in another vi? If you must do it this way, eliminate both lower loops. They are not necessary. The global default is set to false, so when you run the vi, it is false. The button mechanical action is set to latch when released, so after clicking it will turn true until the main vi reads it, then it will automatically turn false. So you don't need the lower loops to keep writing false to it. If you just eliminate both lower loops, it will work fine. The only purpose I could see for the quitter vi is to have one button cause several vi's to stop. Instead of doing it this way, put one stop button in your main vi, create a reference (right click - create - reference), and wire this reference into all subvi's that the main calls. The subvi's must be changed to accept the reference and use it. This would be a much better method to close all vi's with one button.
You could also get rid of the sequence structure (it hides code and makes it more difficult to read). Just put all your code side by side. The error in/out wire will ensure that the execution order will be fixed, just like in your first sequence with the open file and write file functions. Just wire the error out of the write vi to the second write vi, and then the error out of the second write vi to the close vi. No sequence structure needed, and all your code is viewable on one screen.
- tbob
Inventor of the WORM Global

How to assign bean value to a local variable in JSP using struts.

Hi everybody!
I've a problem that puzzled me on how to assign a bean value to a local variable like String in JSP using struts.
we can have someting like this to display the value
<bean:write name="detailService" property="status" />or
<bean:define id="theStatus" name="detailService" property="status"/>
This is country: <%=theStatus%>but an error occured when I tried like this:
String currentStatus = "<bean:define id="theStatus" name="detailService" property="status"/>";
or
String currentStatus = "<bean:write name="detailService" property="status" />";Is there a way to do this?.....
Any help pretty much appreciated

Java != JSP.
The <bean:define> and <bean:write> tags are custom tags meant to appear in the HTML section of a JSP file, as opposed to the scriptlet section. They actually get turned into java code as part of the translation process.
The <bean:write> tag naturally just writes out what you tell it to.
The <bean:define> tag defines a local variable, and gives it a value.
this should do it.
<bean:define id="theStatus" name="detailService" property="status" type="java.lang.String"/>
<%
String currentStatus = theStatus;
%>With the advent of JSTL, you shouldn't really need to use scriptlet code anymore. Personally I am for 0% scriptlet code in any jsp I write.

RE: local variable cross-talk?

Jeff
A global can be considered as a variable to the entire code, where lots of
different vi's can operate it. Locals only have any meaning within their
own vi, or instances of their own vi.
If anything writes to a particular global, whether in reenterent vi's or
not, it's available everywhere in the code.
What you were asking was about locals though. If a vi is non-renentrant
(i.e. as they come out of the box) then the values in the locals are vi
specific, no matter where the vi is, where it was last used, it retains the
data from it's last operation. If it is re-entrant, then the values in the
locals for each occurance of the vi are its own for EACH instance, i.e. just
like different locals in different vi's, it doesn't matter where else the vi
is used, the data held is that from the last operation of that specific
instance.
Simple way to demonstrate this. Make a vi that has one numeric control,
then code in +1 and get it to write to a local variable for that control.
Throw in an indicator to wire out the result of what is written to the local
for the control.
Then take this vi, put it in a for loop, then put another copy in the for
loop as well. Wire the indicators to the side of the for loop and create
indicator arrays for them. Get the loop to run 6 times say. Now try
running this with the vi in the for loop non-reentrant and then reenterrant.
One way the arrays will contain either all the odd no.s 1,3,5,7,9,11 and
then the other array 2,4,6,8,10,12 (don't know which array will be which,
depends which executes first in the for loop of this example). The other
way they will both be 1,2,3,4,5,6. In the first example, the same vi has
run 12 times, i.e. one copy of the vi which retains its info and is called
in many places and therefore only has one set of values, and the other with
two re-enterant copies where they have their information specific to that
instance of them i.e. effectively they are different vi's. Both ways are
useful, depends what you want.
If you're looking for a use for non-reenterant vi's then consider this:-
For instance. Supposing you get many things to try to write to a global
array of numbers, and you have two vi's one "A" writes to the first element
in the array and the other "B" writes to the second element. Because in LV
you have to read a global first and then write to it to perform a change,
these independant vi's "A" and "B" (be they re-enterant versions of the same
vi, or different vi's), can be performing the tasks simultaneously in the
code. I.e. "A" reads, "B" reads, "A" writes, and "B" writes over the top
with a modified version of what it read, and "A"'s changes are lost. This
is what's known as a "race condition" as "A" hadn't finished and "B" needed
to know what "A" was going to write before "B" performed "A" read. Try it,
hours of fun if you code this kind of thing in inadvertantly!
If the same vi is used, and is not re enterant, it can only run in one
instance at a time, hence two read / write operations cannot be performed
together, problem solved. Unless that gives you timing issues of course,
waiting for one to finish, to write the other......but that's another whole
can of worms.
cheers
Tim Price
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-----Original Message-----
From: [email protected]
[mailto:[email protected]]On Behalf Of Jeffrey W Percival
Sent: 29 November 2001 21:12
To: [email protected]
Subject: Re: local variable cross-talk?
Another useful reply! What a great news group this is.
One last thing I wanted to ask about, though, is global vs. local. I see
you talk about globals, but in fact the variables in my subVI's were locals.
I can easily understand the behavior I observed accompanying the use of
global variables, But I guess the use of the word "local" stumped me.
Should I interpret "local" in LabVIEW's sense to mean "local to all
instances of this VI"? And global to mean "visible to all instances of this
VI as well as other VI's"?
-Jeff
Tim Price wrote:
This facility is actually very useful, for instances where you want to
encapsulate some code so that it can only run in one place at a time,
i.e.
global arrays that are written to in more than one place. This method
can
eradicate race conditions completely for example when used like this.
There
are multiple other uses as well.
However, using a vi as a module of code, to run in more than one
instance at
a time simultaneously, re-entrant is the way to go. Just make sure you
debug it first!!!
Remember though, just because a vi may be re-eneterant, doesn't mean
that
everything inside is; sub-vi's, Globals etc. The classic one I've seen
is
where people think that a re-enterant vi is talking to it's own copy of
any
Globals used within it, i.e. counters etc., where in actual fact of
course,
they are all using the same Globals.
Worth playing with a few examples to get familiar with it.
Tim Price
Jeffrey W Percival, Senior Scientist and Associate Director
Space Astronomy Laboratory, University of Wisconsin - Madison
1150 University Ave, Madison, WI 53706 USA
608-262-8686 (fax 608-263-0361) [email protected]
http://www.sal.wisc.edu/~jwp

Tim Price wrote:
Tim, thanks very much. I'll try the experiment you suggest.
Thanks for taking the time.
-Jeff
Jeffrey W Percival, Senior Scientist and Associate Director
Space Astronomy Laboratory, University of Wisconsin - Madison
1150 University Ave, Madison, WI 53706 USA
608-262-8686 (fax 608-263-0361) [email protected] http://www.sal.wisc.edu/~jwp

Local variable needs to be declared final

This is the error code I am getting:
C:\javacode\Notepad>javac FinalProgram.java
FinalProgram.java:60: local variable textfield1 is accessed from within inner class; needs to be declared final
System.out.println("It is detected " + pressed +
textfield1);
^
1 error
Here is my code:
comments relevant to this topic are //ALL IN CAPS
import java.awt.*; //declare packages needed
import java.awt.event.*;
import java.io.*;
import java.util.*;
import javax.swing.*;
import javax.swing.JMenuBar;
public class FinalProgram extends JFrame
    implements ActionListener {
static JFrame frame;
public void actionPerformed (ActionEvent e) {
      String answer = (e.getActionCommand());
         if (answer == "Get Data") {
          JInternalFrame iFrame = new JInternalFrame("Get Data . ", false, true, false, false);
          iFrame.setLayout(new GridLayout(8,2));
          JLabel label1 = new JLabel("First Name");
          JLabel label2 = new JLabel("Last Name");
          JLabel label3 = new JLabel("Street");
          JLabel label4 = new JLabel("City");
          JLabel label5 = new JLabel("State");
          JLabel label6 = new JLabel("Zip");
          JLabel label7 = new JLabel("Phone");
          JLabel label8 = new JLabel("Click Button to Submit Form -->");
          JTextField textfield1 = new JTextField(10);
          JTextField textfield2 = new JTextField(10);
          JTextField textfield3 = new JTextField(10);
          JTextField textfield4 = new JTextField(10);
          JTextField textfield5 = new JTextField(10);
          JTextField textfield6 = new JTextField(10);
          JTextField textfield7 = new JTextField(10);
          JButton button1 = new JButton("Submit Data");
          //textfield1.addActionListener(this);
          textfield1.addActionListener(this);
          textfield2.addActionListener(this);
          textfield3.addActionListener(this);
          textfield4.addActionListener(this);
          textfield5.addActionListener(this);
          textfield6.addActionListener(this);
          textfield7.addActionListener(this);
          button1.addActionListener(new ActionListener() { //start button1.addActionListener
          public void actionPerformed(ActionEvent a) { //start button1 actionPerformed
                    String pressed = ((JButton) a.getSource()).getText();
                    System.out.println("button press is detected " + pressed + textfield1); //THIS SYSTEM OUT PRINT IS A TEST, IT WORKS WHEN I DON'T HAVE THE "+ textfield1" PART, IT GIVES ME THE ERROR MESSAGE POSTED ABOVE ABOUT DECLARING IT FINAL.
I'M A BEGINNER, MY GOAL HERE, IN EASY ENGLISH, IS TO GRAB THE DATA FROM EACH TEXTFIELD AND STORE THEM IN VARIABLES, OR MORE IDEALLY IN AN ARRAY SO THAT THE REST OF MY CODE BELOW CAN WRITE THEM TO FILE, I'VE BEEN TRYING THE PAST FEW DAYS ON THIS EXPERIMENTING AND ANY SUGGESTIONS WOULD BE APPRECIATED
          try {
               String directoryName = "c:\\javacode\\Notepad";
               String fileName = "program.txt";
               File output = new File(directoryName,fileName);
               output.createNewFile();
          if (! output.isFile()) {
               System.out.println("File creation of" + output.getPath() + "failed");
        return;
          BufferedWriter out = new BufferedWriter(new FileWriter(output.getPath(), true));
          String[] text = {"This is the text that will be written. \r", //we pass an array, which holds the text to append to the file
                "The text will be written to the file \r",
                "in append mode. If the file does not \r",
                "exist it will be created.\r"}; //WHAT YOU SEE HERE IS JUST A TEST, IN PLACE, I WOULD LIKE TO HAVE THE INFORMATION FOR MY TEXTFIELDS SO THAT I CAN PASS THEM THROUGH A FOR LOOP AS BELOW AND WRITE DATA FOR EACH OF THE TEXTFIELDS TO MY EXTERNAL TEXT FILE
                for(int i = 0; i < text.length; i++) { //using the length of the text message we use out.Write() to write out the data. Notice that all of the code is placed into a try-catch block so we can check for any IOExceptions that occur
       out.write(text[i] + "\n");
          //Here I create the code to grab the actions(grab the text) from the textFields and store them into variables OR into an array
          //after I have created my container to hold the information for my various textFields, then I want to create a for loop to go through each textField and write that information to a text file, separating each textField on its own line
     out.close();
     catch(IOException d) {
     System.out.println("Error writing to file " + d);
               } //end button1.addActionListener
          } //end button1 actionPerformed
          );     //end actionListener statement
          //textfield1.setSize(10, 10);
          iFrame.add(label1);
          iFrame.add(textfield1);
          iFrame.add(label2);
          iFrame.add(textfield2);
          iFrame.add(label3);
          iFrame.add(textfield3);
          iFrame.add(label4);
          iFrame.add(textfield4);
          iFrame.add(label5);
          iFrame.add(textfield5);
          iFrame.add(label6);
          iFrame.add(textfield6);
          iFrame.add(label7);
          iFrame.add(textfield7);
          iFrame.add(label8);
          iFrame.add(button1);
          iFrame.setSize(200, 500);
          iFrame.setVisible(true);
          add(iFrame);
          if (answer == "Display Data") {
          JInternalFrame iFrame = new JInternalFrame("Display Data . ", false, true, false, false);
          JTextArea text = new JTextArea();
          JScrollPane scroller = new JScrollPane();
          scroller.getViewport().add(text);
          iFrame.getContentPane().add(scroller);
          iFrame.setSize(200, 150);
          iFrame.setVisible(true);
          add(iFrame);
public FinalProgram() {
    super ("Menu Example");
    JMenuBar jmb = new JMenuBar();
    JMenu file = new JMenu("Functions");
    JMenuItem item;
    file.add(item = new JMenuItem("Get Data"));
    item.addActionListener (this);
    file.add(item = new JMenuItem("Display Data"));
    item.addActionListener (this);
    jmb.add(file);
    addWindowListener(new ExitListener());
     setJMenuBar (jmb);
    public static void main(String[] args) {
        FinalProgram window = new FinalProgram();
        window.setTitle("Final Program");
        window.setSize(600, 600);
        window.setVisible(true);
}

hi,
Updated Code,
import java.awt.*; //declare packages needed
import java.awt.event.*;
import java.io.*;
import java.util.*;
import javax.swing.*;
import javax.swing.JMenuBar;
public class FinalProgram extends JFrame
    implements ActionListener {
static JFrame frame;
          JLabel label1 = new JLabel("First Name");
          JLabel label2 = new JLabel("Last Name");
          JLabel label3 = new JLabel("Street");
          JLabel label4 = new JLabel("City");
          JLabel label5 = new JLabel("State");
          JLabel label6 = new JLabel("Zip");
          JLabel label7 = new JLabel("Phone");
          JLabel label8 = new JLabel("Click Button to Submit Form -->");
          JTextField textfield1 = new JTextField(10);
          JTextField textfield2 = new JTextField(10);
          JTextField textfield3 = new JTextField(10);
          JTextField textfield4 = new JTextField(10);
          JTextField textfield5 = new JTextField(10);
          JTextField textfield6 = new JTextField(10);
          JTextField textfield7 = new JTextField(10);
          JButton button1 = new JButton("Submit Data");
public void actionPerformed (ActionEvent e) {
      String answer = (e.getActionCommand());
         if (answer == "Get Data") {
          JInternalFrame iFrame = new JInternalFrame("Get Data . ", false, true, false, false);
          iFrame.setLayout(new GridLayout(8,2));
          //textfield1.addActionListener(this);
          textfield1.addActionListener(this);
          textfield2.addActionListener(this);
          textfield3.addActionListener(this);
          textfield4.addActionListener(this);
          textfield5.addActionListener(this);
          textfield6.addActionListener(this);
          textfield7.addActionListener(this);
          button1.addActionListener(new ActionListener() { //start button1.addActionListener
          public void actionPerformed(ActionEvent a) { //start button1 actionPerformed
                    String pressed = ((JButton) a.getSource()).getText();
                    System.out.println("button press is detected " + pressed + textfield1.getText());
          try {
               String directoryName = "c:\\javacode\\Notepad";
               String fileName = "program.txt";
               File output = new File(directoryName,fileName);
               output.createNewFile();
          if (! output.isFile()) {
               System.out.println("File creation of" + output.getPath() + "failed");
        return;
          BufferedWriter out = new BufferedWriter(new FileWriter(output.getPath(), true));
          String[] text = {"This is the text that will be written. \r", //we pass an array, which holds the text to append to the file
                "The text will be written to the file \r",
                "in append mode. If the file does not \r",
                "exist it will be created.\r"}; //WHAT YOU SEE HERE IS JUST A TEST, IN PLACE, I WOULD LIKE TO HAVE THE INFORMATION FOR MY TEXTFIELDS SO THAT I CAN PASS THEM THROUGH A FOR LOOP AS BELOW AND WRITE DATA FOR EACH OF THE TEXTFIELDS TO MY EXTERNAL TEXT FILE
                for(int i = 0; i < text.length; i++) { //using the length of the text message we use out.Write() to write out the data. Notice that all of the code is placed into a try-catch block so we can check for any IOExceptions that occur
       out.write(text[i] + "\n");
          //Here I create the code to grab the actions(grab the text) from the textFields and store them into variables OR into an array
          //after I have created my container to hold the information for my various textFields, then I want to create a for loop to go through each textField and write that information to a text file, separating each textField on its own line
     out.close();
     catch(IOException d) {
     System.out.println("Error writing to file " + d);
               } //end button1.addActionListener
          } //end button1 actionPerformed
          );     //end actionListener statement
          //textfield1.setSize(10, 10);
          iFrame.add(label1);
          iFrame.add(textfield1);
          iFrame.add(label2);
          iFrame.add(textfield2);
          iFrame.add(label3);
          iFrame.add(textfield3);
          iFrame.add(label4);
          iFrame.add(textfield4);
          iFrame.add(label5);
          iFrame.add(textfield5);
          iFrame.add(label6);
          iFrame.add(textfield6);
          iFrame.add(label7);
          iFrame.add(textfield7);
          iFrame.add(label8);
          iFrame.add(button1);
          iFrame.setSize(200, 500);
          iFrame.setVisible(true);
          add(iFrame);
          if (answer == "Display Data") {
          JInternalFrame iFrame = new JInternalFrame("Display Data . ", false, true, false, false);
          JTextArea text = new JTextArea();
          JScrollPane scroller = new JScrollPane();
          scroller.getViewport().add(text);
          iFrame.getContentPane().add(scroller);
          iFrame.setSize(200, 150);
          iFrame.setVisible(true);
          add(iFrame);
public FinalProgram() {
    super ("Menu Example");
    JMenuBar jmb = new JMenuBar();
    JMenu file = new JMenu("Functions");
    JMenuItem item;
    file.add(item = new JMenuItem("Get Data"));
    item.addActionListener (this);
    file.add(item = new JMenuItem("Display Data"));
    item.addActionListener (this);
    jmb.add(file);
    addWindowListener(new ExitListener());
     setJMenuBar (jmb);
    public static void main(String[] args) {
        FinalProgram window = new FinalProgram();
        window.setTitle("Final Program");
        window.setSize(600, 600);
        window.setVisible(true);
class ExitListener extends WindowAdapter {
public void windowClosing(WindowEvent event) {
    System.exit(0);
}

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