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Trying to Reference a Button With a String

I have a situation in an app I'm making where I have an activity that has 15 buttons and a string[] that contains 15 strings. I'm looking for an easy way to assign each string in the string[] to its corresponding button. I was hoping I could somehow do something like:
for(int i; i<myStringArray.length; i++){
String ref = "btn" + (i + 1);
ref.setText(resultString[i]);
}
where all the buttons are labeled "btn1", "btn2", etc so that they could all be accessed with the string "ref". Obviously this doesn't work so I was wondering if there was another way of doing something similar to this instead of doing:
btn1.setText(resultString[0]);
btn2.setText(resultString[1]);
btn3.setText(resultString[2]);
...
thanks for the help!

I think you can solve this by having a Button[] table where you store all your Button objects and then you can access them by index instead of the actual object name:
Button[] btns = new Button[15]
for(int i = 0; i < btns.length; i++) {
btns[i].setText(resultString[i]);
}
Hope that helps.
EDIT: Ofcourse you have to fill your Button[] btns with your objects first.

You can do what you tried using reflection. It would be way better in your case to store your buttons in an Array or a Map instead though.

Count elements of a list using While loop in java

I am passing some parameters in the URL and then I add them in a list. My list has a limit of 5 elements. So if someone adds 6th element in the URL the list would simply ignore it. So I am trying to use a counter but the logic is not working as desired. I am using While loop to achieve this. So if list size is smaller than 5 set the agencyCds otherwise just return the list.
private List<IUiIntegrationDto> generateViewIntegrationReportData(ESignatureIntegrationConfig eSignConfig) throws Exception {
int counter = 1;
if(eSignConfig.getAdditionalAgencyCds() != null ) {
List<String> combinedAgencyCds = new ArrayList<String>();
for(String agencyCd : eSignConfig.getAgencyCd()) {
combinedAgencyCds.add(agencyCd);
}
StringTokenizer token = new StringTokenizer(eSignConfig.getAdditionalAgencyCds().toString(), StringConstants.COMMA);
while(token.hasMoreTokens()) {
combinedAgencyCds.add(token.nextToken());
}
while(combinedAgencyCds.size() < 5) {
counter = counter + 1;
eSignConfig.setAgencyCd(combinedAgencyCds);
}
// eSignConfig.setAgencyCd(combinedAgencyCds);
}
List<IUiIntegrationDto> intgList = getUiIntegrationManager().retrieveUiIntegrationReportData(eSignConfig.getAgencyCd(), eSignConfig.getCreatedDays(),
eSignConfig.getLob(), eSignConfig.getTransactionStatus(), eSignConfig.getAccounts(), eSignConfig.getSortKey(), eSignConfig.getSortOrder());
return intgList;
}
I am not completely sure about this logic if it is correct or if there is nay better approach.
Thanks

Try this instead of the last while in your code:
if(combinedAgencyCds.size() <= 5) {
eSignConfig.setAgencyCd(combinedAgencyCds);
} else {
eSignConfig.setAgencyCd(combinedAgencyCds.subList(0, 5));
}
The full combined list will then be used if it is less than 5 in size. Otherwise, only the first 5 elements are used.
Edit: Or even better:
eSignConfig.setAgencyCd(combinedAgencyCds.subList(0, Math.min(5, combinedAgencyCds.size())));

Ok so let's break down what your code is currently doing.
int counter = 1;
while(combinedAgencyCds.size() < 5) {
counter = counter + 1;
eSignConfig.setAgencyCd(combinedAgencyCds);
}
This snippet of code has a couple things wrong best I can tell. First, this loop has the possibility of running forever or not at all. Because combinedAgencyCds is never being manipulated, the size won't ever change and the logic being checked in the while loop never does anything. Second, there's a more efficient loop for doing this, assuming you don't need the counter variable outside of its usage in the while loop and that is using for loops.
Example syntax is as follows:
for (int i = 0; i < combinedAgencyCds.size(); i++) {
if (i < 5) {
// Do your logic here.
}
else {
break; // Or handle extra values however you want.
}
}
Notice there is no need for the explicit declaration for a counter variable as "i" counts for you.
Now in your actual logic in the loop, I'm not sure what the setAgencyCd method does, but if it simply sets a list variable in the eSignConfig like it appears to, repeating it over and over isn't going to do anything. From what I can see in your code, you are setting a variable with the same value 5 times. If you need any more explanation just let me know and I will be happy to revise the answer.

Copying i value from arraylist to array

So I am making a program that needs to be overwrite value i from ArrayList to value i in array. For the life of me I cannot figure out what I should do. I've tried looking for similar problems here, but can't seem to find them. Obviously, my loop is very wrong as it is, as it is just overwriting the entire loop, but I can't figure it out. Any kind-hearted person want to help me?
BTW, I am using Java with Processing
Dot[] dots = new Dot[16];
ArrayList<Dot> extraDots = new ArrayList<Dot>();
Fill them with values and later ...
for (int i = 0; i < dots.length; ++i) {
if (dots[i].timeRemain == 0 && !dotTouch)
{
//arrayCopy(extraDots, i, dots, i, 1);
//this is basically what I want, but from an arraylist to the array
dots = extraDots.toArray(new Dot[i]); //So, so wrong, I know
dotTouch = true;
}
dotTouch = false;

You mean
dots[i] = extraDots.get(i);
???

i didn't get your problem..
simply you can do like below to copy from arraylist to array
why you are using dots[i].timeRemain and dotTouch. can you clarify??
for (int i = 0; i < dots.length; ++i) {
dots[i] = extraDots.get(i);
}

Using Strings to Call Methods in Java

This is one of the first programs I am writing by myself. I want to make a physics calculator where many objects can interact with each other and give the user an option to add more objects. My idea is to have a for loop that runs through each object pulling on each other like this.
for(int n=1; n<=totalObjs; n++){
objName = "object"+n;
for(int i=1; i<n; i++){
obj2Name = "object"+i
objName.getMass();
//getting mass and position from both
//calculations here}
for(int x=n+1; x<=totalObjs; x++){
//same stuff as in the previous for loop}
}
I know there are probably huge syntax errors or logical errors in that but I'd like to sort through those on my own. Is there some way i could reference objects with the strings?

Is there some way i could reference objects with the strings?
Yes, via a Map<String, SomeType> such as a HashMap<String, SomeType>.
Think of this as being similar to an array or ArrayList, but instead of using number indices, you'd be using String indices.
Now looking at your code however, you might be better off using a simple ArrayList or array, since you appear to be trying to use numeric indices.
e.g.,
// assume a class called GravMass which has Mass, position, and momentum
List<GravMass> gravMassList = new ArrayList<GravMass>();
// fill your list
for(int i = 0; i < gravMassList.size() - 1; i++) {
GravMass gravMass1 = gravMassList.get(i);
int mass1 = gravMass1.getMass();
for(int j = i + 1; j < gravMassList.size(); j++){
GravMass gravMass2 = gravMassList.get(j);
int mass2 = gravMass2.getMass();
//getting mass and position from both
//calculations here}
}
}

Use JTextField to List items

I'm not too familiar with Java GUI programming, and I wanted to do something where I have a loop that spits out a list of stuff and have the JTextField render it in the order it comes out.
I just do not know how the second parameter of the JTextField insert() function works. Right now when I do something like:
for(int i = 0; i < list.size(); i++){
textArea.insert(list.get(i), 0);
}
It does what I want, except it lists everything in backwards order that I put it in. I want it to display everything the other way around.
Thank you for any advice.

All you need to define a temporary string, result and for every item in the list add the string representation to that variable. When you have looped through everything, all you need to do is textArea.setText(result).
String result = "";
for(int i = 0; i < list.size(); i++)
{
result += list.get(i).toString();
}
textArea.setText(result);