FWD » Core Development » User Interface

The following exceptions occur if the conversion 4GL->Java is applied to the attached addressApp.p
compile:
[javac] Compiling 29 source files to /home/sbi/projects/testcases/uast/build/classes
[javac] Picked up JAVA_TOOL_OPTIONS: -javaagent:/usr/share/java/jayatanaag.jar
[javac] /home/sbi/projects/testcases/uast/src/com/goldencode/testcases/AddressApp.java:90: error: cannot find symbol
[javac] frame0.assignScreenValue(new Element(new FieldReference(address, "addrId"), frame0.widgetAddrId()));
[javac] ^
[javac] symbol: method widgetAddrId()
[javac] location: variable frame0 of type AddressAppFrame0
[javac] /home/sbi/projects/testcases/uast/src/com/goldencode/testcases/AddressApp.java:91: error: cannot find symbol
[javac] frame0.assignScreenValue(new Element(new FieldReference(address, "street"), frame0.widgetStreet()));
[javac] ^
[javac] symbol: method widgetStreet()
[javac] location: variable frame0 of type AddressAppFrame0
[javac] /home/sbi/projects/testcases/uast/src/com/goldencode/testcases/AddressApp.java:92: error: cannot find symbol
[javac] frame0.assignScreenValue(new Element(new FieldReference(address, "state"), frame0.widgetState()));
[javac] ^
[javac] symbol: method widgetState()
[javac] location: variable frame0 of type AddressAppFrame0
[javac] /home/sbi/projects/testcases/uast/src/com/goldencode/testcases/AddressApp.java:93: error: cannot find symbol
[javac] frame0.assignScreenValue(new Element(new FieldReference(address, "zipCode"), frame0.widgetZipCode()));
[javac] ^
[javac] symbol: method widgetZipCode()
[javac] location: variable frame0 of type AddressAppFrame0
[javac] /home/sbi/projects/testcases/uast/src/com/goldencode/testcases/AddressApp.java:94: error: cannot find symbol
[javac] frame0.assignScreenValue(new Element(new FieldReference(address, "addrType"), frame0.widgetAddrType()));
[javac] ^
[javac] symbol: method widgetAddrType()
[javac] location: variable frame0 of type AddressAppFrame0
[javac] Note: Some input files use unchecked or unsafe operations.
[javac] Note: Recompile with -Xlint:unchecked for details.
[javac] 5 errors

May be it is because of the fist trigger is linked to a new frame, but the second trigger is linked to the defined frame AddrFrame
Here is the listing of addressApp.p:

define button ExitButton label "Exit".
define button AddButton label "Add".
define button FindButton label "Find".
define var target like Address.city.

/**Frame Address**/

define frame AddrFrame
Address.addr-id at row 2 col 2
Address.addr-type at row 2 col 40
target at row 4 col 2
Address.state at row 4 col 40
Address.street at row 6 col 2
Address.zip-code at row 8 col 2
AddButton at row 10 col 2
FindButton at row 10 col 20
ExitButton at row 10 col 40
with side-labels centered row 2 title "Address Form".
/**Triggers**/
*on choose of AddButton
do:
create Address.
assign Address except Address.city.
assign Address.city=target.
end. *
on choose of FindButton
do:
assign target.
find first Address where Address.city = target no-error.
if available(Address)
then do:
display Address except Address.city with frame AddrFrame.
end.
else do: Message "Couldn't find " + target
view-as alert-box title "Warning.".
end.

end.

find first Address.
if available(Address)
then target = Address.city.

display Address except Address.city with frame AddrFrame.

enable all with frame AddrFrame.
wait-for choose of ExitButton.

The conversion process produces for the first trigger this java code:

public class TriggerBlock0
   extends Trigger
{
   {
         frame0 = GenericFrame.createFrame(AddressAppFrame0.class, "");
      }
      public void body()
   {
         address.create();
         RecordBuffer.startBatch();
         frame0.assignScreenValue(new Element(new FieldReference(address, "addrId"), frame0.widgetAddrId()));
         frame0.assignScreenValue(new Element(new FieldReference(address, "street"), frame0.widgetStreet()));
         frame0.assignScreenValue(new Element(new FieldReference(address, "state"), frame0.widgetState()));
         frame0.assignScreenValue(new Element(new FieldReference(address, "zipCode"), frame0.widgetZipCode()));
         frame0.assignScreenValue(new Element(new FieldReference(address, "addrType"), frame0.widgetAddrType()));
         RecordBuffer.endBatch();
         RecordBuffer.startBatch();
         address.setCity(target);
         RecordBuffer.endBatch();
{
      public void body()
   {
         addrframeFrame.assignScreenValue(new Element(target, addrframeFrame.widgetTarget()));
         ErrorManager.silentErrorEnable();
         new FindQuery(address, "upper(address.city) = ?", null, "address.city asc, address.state asc", new Object[]
      {
            toUpperCase(target)
         }).first();
         ErrorManager.silentErrorDisable();
         if (address._available())
      {
            FrameElement[] elementList1 = new FrameElement[]
         {
               new Element(new FieldReference(address, "addrId"), addrframeFrame.widgetAddrId()),
               new Element(new FieldReference(address, "street"), addrframeFrame.widgetStreet()),
               new Element(new FieldReference(address, "state"), addrframeFrame.widgetState()),
               new Element(new FieldReference(address, "zipCode"), addrframeFrame.widgetZipCode()),
               new Element(new FieldReference(address, "addrType"), addrframeFrame.widgetAddrType())
            };

addrframeFrame.display(elementList1);
         }
         else
{
            messageBox(concat(new character("Couldn't find "), target), ALERT_MESSAGE, BTN_OK, "Warning.");
         }
      }
   }

Greg pointed out that there is some implicit scoping that goes on with a trigger, such that the references inside the trigger will be first resolved against any frame that is involved in the widget specification (AddButton in this case).

if the first trigger

/**Triggers**/
on choose of AddButton
do:
create Address.
assign Address except Address.city.
assign Address.city=target.
end.
is changed to this one
/**Triggers**/
on choose of AddButton
do:
create Address.
assign frame AddrFrame target.
assign frame AddrFrame Address.addr-id.
assign frame AddrFrame Address.addr-type.
assign frame AddrFrame Address.state.
assign frame AddrFrame Address.street.
assign frame AddrFrame Address.zip-code.
assign Address.city=target.
end.

then the conversion process is successfully performed.