thx
Modifies the extension so that each margin and each corner radius can be set separately.
Update:
Hi, may I ask if I can disable or adjust the shadows? Also, can ! control the background colour, spacing and text alignment of each element by adding more parameters? I don't know how to use dynamic components or comp creator, so I wanna ask if there are any more extensions available. Thx
This is my current listview.
I want to make it look like this:
(no shadow, more spacing, individual text alignment and colours)
Thank you so much for your help 
Hello. This is not possible with this extension. This extension only adds a few simple methods to the original ListView component. It's not easy to add many other methods to a ListView component from an extension. You need to look for an extension that creates the RecyclerView component from scratch. Or use the method with dynamic component creation.
Hi There. Nice extension.
Not sure if you're aware, but this extension doesn't seem to work under the emulator. When starting the TestListViewPlus example project using the emulator the following error is reported:
Runtime Error
invoke: no method named "CreateElement" in class java.lang.Boolean.
Sometimes the following is reported instead:
Runtime Error
Error from Companion: java.lang.RuntimeException: invalid syntax in eval form: :63:1: caught exception in inliner for # - java.lang.RuntimeException: no such class: pl.listviewplus.ListViewPlus gnu.bytecode.ObjectType.getReflectClass(ObjectType.java:179) gnu.bytecode.ClassType.getModifiers (ClassType.java:103) gnu.bytecode.ClassType.isInterface(ClassType.java:471) gnu.expr.InlineCalls.checkType(InlineCalls.java:56) gnu.expr.InlineCalls.visit(InlineCalls.java:49) gnu.expr.InlineCalls.visitSetExpValue(InlineCalls.java:363) gnu.expr.InlineCalls.visitSetExpValue(InlineCalls.java:28) gnu.expr.ExpVisitor.visitSetExp(ExpVisitor.java:114) gnu.expr.InlineCalls.visitSetExp(InlineCalls.java:369) gnu.expr.InlineCalls.visitSetExp(InlineCalls.java:28) gnu.expr.SetExp.visit(SetExp.java:406) gnu.expr.ExpVisitor.visit(ExpVisitor.java:55) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visitBeginExp(InlineCalls.java:272) gnu.expr.InlineCalls.visitBeginExp(InlineCalls.java:28) gnu.expr.BeginExp.visit(BeginExp.java:156) gnu.expr.ExpVisitor.visit(ExpVisitor.java:51) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visitBeginExp(InlineCalls.java:272) gnu.expr.InlineCalls.visitBeginExp(InlineCalls.java:28) gnu.expr.BeginExp.visit(BeginExp.java:156) gnu.expr.ExpVisitor.visit(ExpVisitor.java:51) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visitLetExp(InlineCalls.java:317) gnu.expr.InlineCalls.visitLetExp(InlineCalls.java:28) gnu.expr.LetExp.visit(LetExp.java:207) gnu.expr.ExpVisitor.visit(ExpVisitor.java:51) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visit(InlineCalls.java:28)
gnu.expr.LambdaExp.visitChildren Only(LambdaExp.java:1664) gnu.expr.LambdaExp.visitChildren(LambdaExp.java:1651) gnu.expr.InlineCalls.visitScopeExp(InlineCalls.java:279) gnu.expr.InlineCalls.visitLambda Exp(InlineCalls.java:349) gnu.expr.InlineCalls.visitLambdaExp(InlineCalls.java:28) gnu.expr.LambdaExp.visit(LambdaExp.java:1640) gnu.expr.ExpVisitor.visit(ExpVisitor.java:55) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visit(InlineCalls.java:28)
gnu.expr.ExpVisitor.visitAndUpdate(ExpVisitor.java:161) gnu.expr.ExpVisitor.visitExps (ExpVisitor.java:175) gnu.expr.ApplyExp.visitArgs(ApplyExp.java:415)
gnu.kawa.reflect.CompileInvoke.validateApplyinvoke(Compilelnvoke.java:23) java.lang.reflect.Method.invoke(Native Method) gnu.expr.InlineCalls.maybelline (InlineCalls.java:467) gnu.expr.QuoteExp.validateApply(QuoteExp.java:150) gnu.expr.ReferenceExp.validateApply (ReferenceExp.java:191)
gnu.kawa.functions.CompilationHelpers.validateApply ToArgs(Compilation Helpers.java:66) java.lang.reflect.Method.invoke(Native Method)
gnu.expr.InlineCalls.maybelline (InlineCalls.java:467) gnu.expr.QuoteExp.validateApply(QuoteExp.java:150) gnu.expr.ReferenceExp.validateApply(ReferenceExp.java:191) gnu.expr.InlineCalls.visitApplyExp(InlineCalls.java:119) gnu.expr.InlineCalls.visitApplyExp(InlineCalls.java:28) gnu.expr.Apply Exp.visit(ApplyExp.java:410)
gnu.expr.ExpVisitor.visit(ExpVisitor.java:55) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.QuoteExp.validateApply(QuoteExp.java:162)
gnu.expr.ReferenceExp.validateApply(ReferenceExp.java:191) gnu.kawa.functions.Compilation Helpers.validateApplyToArgs(Compilation Helpers.java:66)
java.lang.reflect.Method.invoke(Native Method) gnu.expr.InlineCalls.maybelline (InlineCalls.java:467) gnu.expr.QuoteExp.validateApply(QuoteExp.java:150)
gnu.expr.ReferenceExp.validateApply(ReferenceExp.java:191) gnu.expr.InlineCalls.visitApplyExp(InlineCalls.java:119) gnu.expr.InlineCalls.visitApplyExp(InlineCalls.java:28) gnu.expr.InlineCalls.visitBeginExp(InlineCalls.java:272) gnu.expr.InlineCalls.visitBeginExp(InlineCalls.java:28) gnu.expr.BeginExp.visit(BeginExp.java:156) gnu.expr.ExpVisitor.visit(ExpVisitor.java:51) gnu.expr.InlineCalls.visit(InlineCalls.java:46) gnu.expr.InlineCalls.visit(InlineCalls.java:28)
gnu.expr.ApplyExp.visit(ApplyExp.java:410) gnu.expr.ExpVisitor.visit(ExpVisitor.java:51) gnu.expr.InlineCalls.visit(InlineCalls.java:46)
gnu.expr.LambdaExp.visitChildren Only(LambdaExp.java:1664) gnu.expr.LambdaExp.visitChildren(LambdaExp.java:1651) gnu.expr.InlineCalls.visitScopeExp(InlineCalls.java:279) gnu.expr.InlineCalls.visitLambda Exp(InlineCalls.java:349) gnu.expr.InlineCalls.visitLambdaExp(InlineCalls.java:28) gnu.expr.ExpVisitor.visitModule Exp(ExpVisitor.java:103)
gnu.expr.ModuleExp.visit(ModuleExp.java:482) gnu.expr.ExpVisitor.visit(ExpVisitor.java:51) gnu.expr.InlineCalls.visit(InlineCalls.java:46)
gnu.expr.InlineCalls.inlineCalls (InlineCalls.java:33) gnu.expr.Compilation.walkModule(Compilation.java:994) gnu.expr.Compilation.process(Compilation.java:1965)
gnu.expr.ModuleInfo.loadByStages (ModuleInfo.java:330) gnu.expr.ModuleExp.evalModule1 (ModuleExp.java:238) gnu.expr.ModuleExp.evalModule(ModuleExp.java:198) gnu.expr.Language.eval(Language.java:943) gnu.expr.Language.eval(Language.java:883) gnu.expr.Language.eval (Language.java:865) com.google.appinventor.components.runtime.util.AppInvHTTPD.serve(AppInvHTTPD.java:197) com.google.appinventor.components.runtime.util.NanoHTTPD$HTTPSession.run(NanoHTTPD.java:489)
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641)
java.lang.Thread.run(Thread.java:923)
The emulator appears to be running Android 11.
The same example works fine on my Phone though. My phone is running Android 9.
Cheers, Tim.
are you using USB to connect to the companion app?
does it work after building using the apk file?
try to connect via wifi
see also this thread
Regarding the extensions over USB issue, I believe I have identified the source of the problem and submitted a fix.
Taifun
The emulator runs on the same PC as the web browser I'm using to run the App Inventor UI. It appears to connect to aiStarter using localhost. I start it from the Connect menu, choosing Emulator. This starts the emulator, and then the companion App (within the Emulator), and then runs the project. I have aiStarter installed, and running, and all my projects seem to work fine under the Emulator with this setup. When I try to run the TestListViewPlus project, or I include the ListViewPlus extension in a project, I get the messages I reported previously.
I don't unserstand how I'd use USB or Wifi to connect to the emulator that's running on my PC...? Perhaps you're thinking I have the companion app on my phone, and I could understand if this were the case, but it's not. I could try it I guess, but I haven't at this point.
Cheers, Tim.
I don't use an emulator so I don't know about emulator errors. Does your emulator have the latest Companion installed? CreateElement is a block from the built-in ListView component. So either your Companion is not up to date or there is some problem with the ListView. Make a project with just ListView without the ListViewPlus extension and try it out.
You are using an emulator...
In this case try a device and connect via Wifi or test using the apk file
Taifun
Hi Patryk,
I believe it does have the latest companion installed. I just installed the emulator a few days a ago for the first time, so I'd be surprised if it was old. It reports version 2.65u when the emulator starts up.
No, my app that has a ListView in it works fine under the emulator, until I add ListViewPlus extension (that does nothing, just added an instance to screen1.) I've noticed now though, that another extension I tried (Ai2Tools) reports similar errors, so I may be unfairly singling out ListViewPlus, and it could be a general thing for extensions that use reflection to delve in to the internals.
Cheers, Tim.
Hi Taifun,
A built .apk works fine on my phone. I just like using the emulator on the PC as it is so much more convenient for quick testing while developing.
And I'm only pointing out that it doesn't work under the emulator in case it'd be releatively simple to fix at some time in the future. In the mean time I can live with using my phone to test with.
Cheers, Tim.
Thank you for pointing it out
Let's see, if ithis will be fixed in the next release after this patch has been implemented
Taifun
The current companion version is 2.68. Install the latest version of the companion.
Hi Patryk,
Updating the companion App via the Help / Update the Companion menu item unfortunately didn't seem to work for me (messages appeared in App Inventor saying the install was progressing etc., but nothing appeared in the emultor to be accepted, and the version never updated from 2.65u.)
On googling a bit I found this page: https://community.appinventor.mit.edu/t/aistarter-update-mit-ai2-companion2-to-2-58au/7587. The instructions seemed a bit out of date, but I managed to follow them, and successfully updated the companion app in the emulator to version 2.68u.
Old report in aiStarter:
127.0.0.1 - - [03/Oct/2023 13:32:56] "GET /echeck/ HTTP/1.1" 200 39
Found emulator at emulator-5554
Found companion version 13126500
New report in aiStarter:
127.0.0.1 - - [03/Oct/2023 15:06:40] "GET /ping/ HTTP/1.1" 200 88
Found emulator at emulator-5554
Found companion version 13326800
Unfortunately the same errors as I reported previously still occur.
Cheers, Tim.
I like the extension, it works well and is easy to use. I do have one question.. I see a block that sets the color of the background in ListView .. but is there a block to set the background color of the item? In the example pictured above, the ListView background is a pinkish color and each element/item is light blue .. can that blue color be set with a block?
The element takes the color set in the original ListView component's BackgroundColor property.
The scroll animation is a bit jerky, can you get it to smooth scroll?
This block:
scrolling one item at a time
Can you give more context? What is the counter variable? Want a slow scrolling effect?