I am getting a error while returning a list?

Extensions Extensions IDE
#1

i am getting a error while returning a list ??

how to return a list ??

my code

two variables -

public String[] Strr;
public String[] pkgList;

code in
@SimpleFunction

    String[] Strr = new String[] {ExampleList};
          this.Strr = Strr;

return Strr;

Sur, @hammerhai kindly take a look.

#4

Hello @AryanGupta,

I am glad you felt the need to mention me in the first post, however with other people it can be a burden to them. Please do not mention someone in the first post again.

To return a list you would actually do…

/** Do not use a wildcard for the YailList (such as com.google.appinventor.components.runtime.util.*), instead reference the class otherwise it will not work **/
import com.google.appinventor.components.runtime.util.YailList;
...

@SimpleFunction
public YailList ReturnListExample() {
  YailList myList = new YailList();
  myList.addItem("String");

  return myList;
}

If doing myList.addItem("String") on that example gives you an error, then do the following instead…

import java.util.ArrayList;
import java.util.List;
...

@SimpleFunction
public List ReturnListExample() {
  List myList = new ArrayList();
  myList.addItem("String");

  return myList;
}

Now if the previous example didn’t work (which it should as from the code from my extensions source), the last try would be…

import java.util.ArrayList;
...

@SimpleFunction
public ArrayList ReturnListExample() {
  ArrayList myList = new ArrayList();
  myList.addItem("String");

  return myList;
}

But, try the first 2 examples and see where you get before resorting to the final solution!

1 Like
#5

can i use a Variable Like this.list instead of (“String”)

#6 
@SimpleFunction
public ArrayList PackageNames() {

return ExampleList;
}

not working ??

#7

i want to say that i don’t want to create any ArrayList. because i have already a list named ExampleList.

now, i wanted to return this ExampleList list.

#8

@hammerhai please help

#9

Ok let me rephrase the question so that I understand better, and you tell me if it’s correct.

You have an ArrayList, but you want to return it as a YailList?

#10

i have a ArrayList And i want to return ArrayList;

but it saying unable to convert String to String.

#11

Can you show me what you have as your ExampleList variable? Like what does it equal?

EDIT: I have to go to sleep so I will help you when I wake up.

#12

i don’t know what is in it ??
because i am getting a unKnown Value

#13

Wake Up bru :wink:

#14

i just created YailList But i still getting a error

error: YailList(Object) has private access in YailList
    [javac] return new YailList(myList);

@Mohamed_Tamer Sur, kindly take a look

#15

I just don’t understand why you would want to return ArrayList, because Kodular (AI2) won’t be able to cast it for you.

To convert ArrayList to YailList, do
YailList.makeList(YOUR_ARRAYLIST);

1 Like
#16

what are you saying ??

1 Like
#17

and BTW, i i have ArrayList . so, i am converting it to YailList.

#18

Yes, if you can kindly read my post:

1 Like
#19

how can i return it ??

#20

return YailList.makeList(ArrayList);

Remember the type you’re returning is YailList, so the top should be like this:

@SimpleFunction(description = "")
public YailList YourMethod() {...}
1 Like
#21

let me try

#22

Thank you for doing that @WatermelonIce :sweat_smile: I didn’t wake up til a few minutes ago!

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