jSpinner functions Clear() and Add() work only in OnCreate event
lazarus / 43-Android

----------------------------------------------------------------------
neuro · 2025-11-03 14:32

jSpinner functions Clear() and Add() work only in OnCreate event:
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i
TAndroidModule1.AndroidModule1Create(Sender: TObject);begin 
jSpinner1.Items.Clear(); // <-- works ok 
jSpinner1.Items.Add('hello');  // <-- works ok 
jSpinner1.Items.Add('world');  // <-- works okend;
jSpinner functions Clear() and Add() do not work when App is running:
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i procedure
TAndroidModule1.jButton1Click(Sender: TObject);begin 
jSpinner1.Items.Clear(); // <-- does not work 
jSpinner1.Items.Add('hello');  // <-- does not work 
jSpinner1.Items.Add('world');  // <-- does not workend;
How to fix this problem?

LAWM program code has two files:
QuoteC:\fpcupdeluxe\ccr\lamw\android_wizard\smartdesigner\java\jSpinne
r.java
C:\fpcupdeluxe\ccr\lamw\android_wizard\smartdesigner\java\jSpinner_new
.javaWhy there are two files instead of one?

----------------------------------------------------------------------
neuro · 2025-11-04 16:56

I have found out how to fix the problem.
You need to use two different program codes for 1) OnCreate event and
2) when app is already running.

In OnCreate event the program code should be like this:
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i  
jSpinner1.Items.Clear(); // <-- works only in OnCreate event, does not
work when app is already running  jSpinner1.Items.Add('hello');  //
<-- works only in OnCreate event, does not work when app is already
running  jSpinner1.Items.Add('world');  // <-- works only in OnCreate
event, does not work when app is already running
When app is already running the program code should be without word
”Items”:
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i  
jSpinner1.Clear(); // <-- works only when app is already running, does
not work in OnCreate event  jSpinner1.Add('hello');  // <-- works only
when app is already running, does not work in OnCreate event 
jSpinner1.Add('world');  // <-- works only when app is already
running, does not work in OnCreate event
The biggest problem with LAMW is that it uses Android components which
are very different from standard Lazarus components and when you are
porting program code from Windows into Android, the copy/pasted
program code fails to work as expected.
Another problem with LAMW is that there are no sample projects for
huge number of functions of LAMW and you need to spent massive amount
of time wondering in the dark without any guidance.