https://community.sap.com/t5/technology-q-a/how-do-i-develop-a-multithreading-application-within-powerbuilder-classic/qaa-p/380473#M33299 <P>Hi,</P><P>#1: The name must be unique for registered objects in the application. If you try to register a second object with the same name the function SharedObjectRegister should return SharedObjectExistsError!</P><P>You may use a shared or global variable instead of instance variable as thread counter.</P><P>#2: You can't use the transaction object from main thread (SQLCA) in a shared object. You need a separate database connection for each shared object if you want to access the database.</P><P>One parameter of function of_checkvalid of your shared object is a datawindow control. I think the shared object cannot access this object from main thread. You may pass only nonvisualobjects. If you want to check data from a datawindow you may pass it as blob (see function GetFullState / SetFullState).</P><P>To return a result from shared object to main thread you need a (nonvisual) callback object with a function you can call from the shared object.</P><P>HTH</P> Tue, 17 Jan 2017 11:59:39 GMT Former Member 2017-01-17T11:59:39Z https://community.sap.com/t5/technology-q-a/how-do-i-develop-a-multithreading-application-within-powerbuilder-classic/qaq-p/380472 <P>hi guys</P><P> there was a legacy program need to maintain,then I tried to check a batch number of product that if supplies was less than all sells,I believe it's a good experience for </P><P>colleagues that after scaned the barcode of that batch number application then checked the supplies and sells aysnchrously.althought I have searched Google,however Powerbuilder is less infomation I could found about multithreading,it's not a clear instrution in Powerbuilder help as well.</P><P>I'm not sure two questions about multithreading within powerbuilder</P><P>#1 if the exception is going to occur when SharedObjectRegister the same name when open two windows like following? </P><P>code:</P><P>window w_1<BR />opensheet(w_1,"w_inv",w_main,0,Original! )</P><P>// then in two same w_inv windows exectue SharedObjectRegister with same name in a //same time,is it going to ocurr the exception?</P><P>SharedObjectRegister ('nov_checkvalidobject', ls_var)</P><P>#2 some pages said that main thread and sub thread are independent,does it mean that if need to execute SQL select syntax,I can't use sqlca transaction which has connected to a database in main thread?</P><P>please take a look at my code,please give me suggestion that I have done wrong or should be aware.thanks in advance</P><BR /><P>//w_inv instance variable:</P><P>//long ll_multithreadcount<BR />//string is_sbmodel<BR />//nov_checkvalidobject tarea_No[ ]</P><P>//this is wf_multithread_cal</P><P>//long as_row</P><P>string ls_var<BR />ErrorReturn ler_error<BR />long ll_threadcurrent<BR /><BR /><BR /><BR />ll_threadcurrent=ll_multithreadcount<BR />ls_var = 'objeto_' +string(ll_threadcurrent)<BR /><BR /><BR />if is_new='0' then<BR /> cb_add_main.enabled=false<BR /> <BR />elseif is_new='1' then<BR /> cb_delete_main.enabled=false<BR /> cb_delete_sub.enabled=false<BR />end if<BR /><BR />ler_error = SharedObjectRegister ('nov_checkvalidobject', ls_var)<BR /><BR />choose case ler_error<BR /> case SharedObjectExistsError!<BR /> </P><P>messagebox("Error","The instance name is already used",stopsign!)</P><P>if is_new='0' then<BR /> cb_add_main.enabled=true<BR /> <BR />elseif is_new='1' then<BR /> cb_delete_main.enabled=true<BR /> cb_delete_sub.enabled=true<BR />end if</P><P><BR /> return -1<BR /> case SharedObjectCreateInstanceError! <BR /> </P><P>messagebox("Error","The object could not be created",stopsign!)</P><P>if is_new='0' then<BR /> cb_add_main.enabled=true<BR /> <BR />elseif is_new='1' then<BR /> cb_delete_main.enabled=true<BR /> cb_delete_sub.enabled=true<BR />end if</P><P><BR /> return -1<BR /> <BR /> case SharedObjectCreatePBSessionError! <BR /> </P><P>messagebox("Error","The object in the session could not be created",stopsign!) </P><P>if is_new='0' then<BR /> cb_add_main.enabled=true<BR /> <BR />elseif is_new='1' then<BR /> cb_delete_main.enabled=true<BR /> cb_delete_sub.enabled=true<BR />end if</P><P><BR /> return -1<BR /> end choose<BR /><BR /> <BR /> ler_error = SharedObjectGet (ls_var, tarea_No[ll_threadcurrent])<BR /> choose case ler_error<BR /> case SharedObjectCreateInstanceError! <BR /> </P><P>messagebox("Error","The local reference to the shared object could not be created",stopsign!)</P><P>if is_new='0' then<BR /> cb_add_main.enabled=true<BR /> <BR />elseif is_new='1' then<BR /> cb_delete_main.enabled=true<BR /> cb_delete_sub.enabled=true<BR />end if</P><P><BR /> return -1<BR /> case SharedObjectNotExistsError! <BR /> </P><P>messagebox("Error","The instance name is not registered ",stopsign!)</P><P>if is_new='0' then<BR /> cb_add_main.enabled=true<BR /> <BR />elseif is_new='1' then<BR /> cb_delete_main.enabled=true<BR /> cb_delete_sub.enabled=true<BR />end if</P><P><BR /> return -1<BR /> end choose<BR /><BR />tarea_No[ll_threadcurrent].POST of_checkvalid(dw_2,as_row)<BR /> <BR />SharedobjectUnregister(ls_var)<BR /><BR />ll_multithreadcount++<BR /></P><P>if is_new='0' then<BR /> cb_add_main.enabled=true<BR /> <BR />elseif is_new='1' then<BR /> cb_delete_main.enabled=true<BR /> cb_delete_sub.enabled=true<BR />end if</P><P><BR /><BR />return 0</P><P>//nov_checkvalidobject: there is a function in nov_checkvalidobjec which is of_checkvalid</P><P>// there is 2 parameters in it</P><P>//paramter #1 datawindow as_dw</P><P>//paramter #2 long as_therow</P><P>//of_checkvalid function code:</P><P>decimal ld_invnum,ld_depnum<BR />string ls_prodno,ls_batchno,ls_prodadd<BR /><BR />if as_therow&lt;0 or as_therow&gt;as_dw.rowcount() then return -1<BR /><BR />ls_prodno=as_dw.getitemstring(as_therow,"prod_no")<BR />ls_batchno=as_dw.getitemstring(as_therow,"batch_no")<BR />ls_prodadd=as_dw.getitemstring(as_therow,"prod_add")<BR /><BR />if isnull(ls_prodno) or trim(ls_prodno)="" or isnull(ls_batchno) or trim(ls_batchno)="" or isnull(ls_prodadd) or trim(ls_prodadd)="" then return -2<BR /> //check the number of all sells<BR /> select isnull(sum(inv_num),0) into :ld_invnum from inv_sub where prod_no=:ls_prodno and batch_no=:ls_batchno and prod_add=:ls_prodadd;<BR /> </P><P>//check the number of all suppliers</P><P>select isnull(sum(dep_num),0) into :ld_depnum from dep_sub where prod_no=:ls_prodno and batch_no=:ls_batchno and prod_add=:ls_prodadd;<BR /> <BR /> if ld_invnum&gt;ld_depnum then <BR /> as_dw.setitem(as_therow,"if_is_valid","failed")<BR /> return -3<BR />end if<BR /> <BR /><BR />as_dw.setitem(as_therow,"if_is_valid","pass")<BR />return 0</P> Tue, 17 Jan 2017 09:34:44 GMT https://community.sap.com/t5/technology-q-a/how-do-i-develop-a-multithreading-application-within-powerbuilder-classic/qaq-p/380472 Former Member 2017-01-17T09:34:44Z https://community.sap.com/t5/technology-q-a/how-do-i-develop-a-multithreading-application-within-powerbuilder-classic/qaa-p/380473#M33299 <P>Hi,</P><P>#1: The name must be unique for registered objects in the application. If you try to register a second object with the same name the function SharedObjectRegister should return SharedObjectExistsError!</P><P>You may use a shared or global variable instead of instance variable as thread counter.</P><P>#2: You can't use the transaction object from main thread (SQLCA) in a shared object. You need a separate database connection for each shared object if you want to access the database.</P><P>One parameter of function of_checkvalid of your shared object is a datawindow control. I think the shared object cannot access this object from main thread. You may pass only nonvisualobjects. If you want to check data from a datawindow you may pass it as blob (see function GetFullState / SetFullState).</P><P>To return a result from shared object to main thread you need a (nonvisual) callback object with a function you can call from the shared object.</P><P>HTH</P> Tue, 17 Jan 2017 11:59:39 GMT https://community.sap.com/t5/technology-q-a/how-do-i-develop-a-multithreading-application-within-powerbuilder-classic/qaa-p/380473#M33299 Former Member 2017-01-17T11:59:39Z https://community.sap.com/t5/technology-q-a/how-do-i-develop-a-multithreading-application-within-powerbuilder-classic/qaa-p/380474#M33300 <P>Each background thread has its own set of global variables which includes sqlca. The background thread will have to connect to the database before performing any SQL statements.</P><P>When calling SharedObjectRegister, the instancename must be unique. You can create a global variable or shared variable within the window that you increment before each call and use it in the name like this:</P><P>gi_instance ++</P><P>ls_instance = "instance" + String(gi_instance)</P><P>SharedObjectRegister("objectname",ls_instance)</P> Tue, 17 Jan 2017 13:49:21 GMT https://community.sap.com/t5/technology-q-a/how-do-i-develop-a-multithreading-application-within-powerbuilder-classic/qaa-p/380474#M33300 Former Member 2017-01-17T13:49:21Z