actualizing DBcontrols

[Ingo Junge-Herrmann]

Hi,
I'm about to transcribe my apps from FW16 to Xailer using DataControls. But
the devil is in the details.
For example:
Each networkclient can hold the same dialogform open with many datacontrols
on it at the same time. The datacontrols are buffered and write the changed
value into the field when loosing the focus.
Every time when a control gets the focus it reads in the actual value from
the field.
I tried to do the same in Xailer. As I read in the helpfile there isn't it
neccessary to buffer the the field of a database by myself - Xailer does
it for me. Ok that's fine.
But how to actualize the value of the control linked to the databasefield
when the DataSet is on editmode?
I thought the method Load()of TDataField will doit than the helpfile says:
"Loads the current field value in[to] the 'Buffer' and in InitValue. The
lModified is assigned with a .F. value."
I tried it using the event 'OnEnter' with
oSender:oDataField:Load()
But wether oSender:oDataField:Buffer has the new value I changed in the meantime
from an other workstation nor the control.
1. How to do it with Xailer?
2. What is the simpliest way to write the modified DBEdit:value back into
the databasefield without ending the editmode?
Thank you in advance
Ingo

[ignacio]

Ingo,
To reread the data from the table:
oDbfDataSet:Load()
To save the bufffer data to the table:
oDbfDataSet:Save()
This two methods should work in EditMode. If you believe they do not work as
expected please send us a small sample including the DBF file where we can
check it.
BTW be aware that saving a record field with Fieldput() DOES NOT
automatically save the data to disk, so I suggest you put some LogDebug(
FieldGet( "..." ) ) on your code to see if the field is really updated.
Regards,
"Ingo Junge-Herrmann" <[email=XPRO-0031BA74-01@10.0.0.11]XPRO-0031BA74-01@10.0.0.11[/email]> escribió en el mensaje
news:43d3c525$[email=1@ozsrvnegro.ozlan.local...]1@ozsrvnegro.ozlan.local...[/email]
>
> Hi,
>
> I'm about to transcribe my apps from FW16 to Xailer using DataControls.
> But
> the devil is in the details.
> For example:
>
> Each networkclient can hold the same dialogform open with many
> datacontrols
> on it at the same time. The datacontrols are buffered and write the
> changed
> value into the field when loosing the focus.
> Every time when a control gets the focus it reads in the actual value from
> the field.
>
> I tried to do the same in Xailer. As I read in the helpfile there isn't it
> neccessary to buffer the the field of a database by myself - Xailer does
> it for me. Ok that's fine.
>
> But how to actualize the value of the control linked to the databasefield
> when the DataSet is on editmode?
>
> I thought the method Load()of TDataField will doit than the helpfile says:
> "Loads the current field value in[to] the 'Buffer' and in InitValue. The
> lModified is assigned with a .F. value."
>
> I tried it using the event 'OnEnter' with
>
> oSender:oDataField:Load()
>
> But wether oSender:oDataField:Buffer has the new value I changed in the
> meantime
> from an other workstation nor the control.
>
> 1. How to do it with Xailer?
>
> 2. What is the simpliest way to write the modified DBEdit:value back into
> the databasefield without ending the editmode?
>
> Thank you in advance
>
> Ingo

[InvalidAccount]

Ingo,
To reread the data from the table:
oDbfDataSet:Load()
To save the bufffer data to the table:
oDbfDataSet:Save()
This two methods should work in EditMode. If you believe they do not work as
expected please send us a small sample including the DBF file where we can
check it.
BTW be aware that saving a record field with Fieldput() DOES NOT
automatically save the data to disk, so I suggest you put some LogDebug(
FieldGet( "..." ) ) on your code to see if the field is really updated.
Regards,
"Ingo Junge-Herrmann" <[email=XPRO-0031BA74-01@10.0.0.11]XPRO-0031BA74-01@10.0.0.11[/email]> escribió en el mensaje
news:43d3c525$[email=1@ozsrvnegro.ozlan.local...]1@ozsrvnegro.ozlan.local...[/email]
>
> Hi,
>
> I'm about to transcribe my apps from FW16 to Xailer using DataControls.
> But
> the devil is in the details.
> For example:
>
> Each networkclient can hold the same dialogform open with many
> datacontrols
> on it at the same time. The datacontrols are buffered and write the
> changed
> value into the field when loosing the focus.
> Every time when a control gets the focus it reads in the actual value from
> the field.
>
> I tried to do the same in Xailer. As I read in the helpfile there isn't it
> neccessary to buffer the the field of a database by myself - Xailer does
> it for me. Ok that's fine.
>
> But how to actualize the value of the control linked to the databasefield
> when the DataSet is on editmode?
>
> I thought the method Load()of TDataField will doit than the helpfile says:
> "Loads the current field value in[to] the 'Buffer' and in InitValue. The
> lModified is assigned with a .F. value."
>
> I tried it using the event 'OnEnter' with
>
> oSender:oDataField:Load()
>
> But wether oSender:oDataField:Buffer has the new value I changed in the
> meantime
> from an other workstation nor the control.
>
> 1. How to do it with Xailer?
>
> 2. What is the simpliest way to write the modified DBEdit:value back into
> the databasefield without ending the editmode?
>
> Thank you in advance
>
> Ingo

[Ingo Junge-Herrmann]

Ignacio,
here a small sample.
If you changes the value in form1 and leave the editcontrol the value should
be written to the table. If you go to the editcontrol on form2 it should
reread the (changed) value from the table and show it. After changing the
value in form2 and leaving the editcontrol the value should be written to
the table. And that should be done the other way round.
Please consider it should be written and reread only the one field and not
all the fields of the record.
I hope I have explained exactly enough what I mean.
>To reread the data from the table:
>
>oDbfDataSet:Load()
It should not be reread all fields of the record but only the data of one
field
>
>To save the bufffer data to the table:
>
>oDbfDataSet:Save()
It should be saved only the data of one field.
Regards
Ingo
--

Attached files testload.zip (3.4 KB)Â

[Ingo Junge-Herrmann]

Ignacio,
here a small sample.
If you changes the value in form1 and leave the editcontrol the value should
be written to the table. If you go to the editcontrol on form2 it should
reread the (changed) value from the table and show it. After changing the
value in form2 and leaving the editcontrol the value should be written to
the table. And that should be done the other way round.
Please consider it should be written and reread only the one field and not
all the fields of the record.
I hope I have explained exactly enough what I mean.
>To reread the data from the table:
>
>oDbfDataSet:Load()
It should not be reread all fields of the record but only the data of one
field
>
>To save the bufffer data to the table:
>
>oDbfDataSet:Save()
It should be saved only the data of one field.
Regards
Ingo
--

Attached files testload.zip (3.4 KB)Â

[ignacio]

Ingo,
OnExit and OnEnter are only triggered when changing the focus on the SAME
form, so you better use the events OnActivate or OnDeactivate which is
triggered every time the FORM is activated:
METHOD FormDeactivate( oSender, oCtl ) CLASS TForm2
::oDbf:Save()
if oCtl != NIL
oCtl:oDbf:Load()
endif
RETURN Nil
BTW, this only works with the new file I attach to this message because some
modifications have been done in order to work properly due the following
problems:
a) The update of oDataField buffers was done on method Update(), now is
moved to Save() method
b) Load() method did not do a GOTO(RECNO()) operation to force a reread of
RDD internal buffers
c) Load() method did not refresh any linked control
Regards,
"Ingo Junge-Herrmann" <[email=XPRO-0031BA74-01@10.0.0.11]XPRO-0031BA74-01@10.0.0.11[/email]> escribió en el mensaje
news:43d4b2da$[email=1@ozsrvnegro.ozlan.local...]1@ozsrvnegro.ozlan.local...[/email]
>
> Ignacio,
>
> here a small sample.
>
> If you changes the value in form1 and leave the editcontrol the value
> should
> be written to the table. If you go to the editcontrol on form2 it should
> reread the (changed) value from the table and show it. After changing the
> value in form2 and leaving the editcontrol the value should be written to
> the table. And that should be done the other way round.
>
> Please consider it should be written and reread only the one field and not
> all the fields of the record.
>
> I hope I have explained exactly enough what I mean.
>
>>To reread the data from the table:
>>
>>oDbfDataSet:Load()
>
> It should not be reread all fields of the record but only the data of one
> field
>>
>>To save the bufffer data to the table:
>>
>>oDbfDataSet:Save()
>
> It should be saved only the data of one field.
>
> Regards
>
> Ingo


Attached files DbfDataSet.rar (11.2 KB)Â

[InvalidAccount]

Ingo,
OnExit and OnEnter are only triggered when changing the focus on the SAME
form, so you better use the events OnActivate or OnDeactivate which is
triggered every time the FORM is activated:
METHOD FormDeactivate( oSender, oCtl ) CLASS TForm2
::oDbf:Save()
if oCtl != NIL
oCtl:oDbf:Load()
endif
RETURN Nil
BTW, this only works with the new file I attach to this message because some
modifications have been done in order to work properly due the following
problems:
a) The update of oDataField buffers was done on method Update(), now is
moved to Save() method
b) Load() method did not do a GOTO(RECNO()) operation to force a reread of
RDD internal buffers
c) Load() method did not refresh any linked control
Regards,
"Ingo Junge-Herrmann" <[email=XPRO-0031BA74-01@10.0.0.11]XPRO-0031BA74-01@10.0.0.11[/email]> escribió en el mensaje
news:43d4b2da$[email=1@ozsrvnegro.ozlan.local...]1@ozsrvnegro.ozlan.local...[/email]
>
> Ignacio,
>
> here a small sample.
>
> If you changes the value in form1 and leave the editcontrol the value
> should
> be written to the table. If you go to the editcontrol on form2 it should
> reread the (changed) value from the table and show it. After changing the
> value in form2 and leaving the editcontrol the value should be written to
> the table. And that should be done the other way round.
>
> Please consider it should be written and reread only the one field and not
> all the fields of the record.
>
> I hope I have explained exactly enough what I mean.
>
>>To reread the data from the table:
>>
>>oDbfDataSet:Load()
>
> It should not be reread all fields of the record but only the data of one
> field
>>
>>To save the bufffer data to the table:
>>
>>oDbfDataSet:Save()
>
> It should be saved only the data of one field.
>
> Regards
>
> Ingo


Attached files DbfDataSet.rar (11.2 KB)Â

[Ingo Junge-Herrmann]

Ignacio,
sorry you misunderstood me again.
>OnExit and OnEnter are only triggered when changing the focus on the SAME
>form, so you better use the events OnActivate or OnDeactivate which is
>triggered every time the FORM is activated:
No, please pay attention that I'm talking about xBase apps which are running
in a network on different workstations at the same time. Therefore it is
necessary that all the controls in a form wich are holding datas from the
shared database file will be actualized when the user enter them.
Therefore the question is, how to reread the data from the field which is
linked with the control when the control gets the focus and how to write
modified values back when it looses the focus.
Only to show you what the problem is the sample uses two forms. Form1 stands
for workstation no 1 and Form2 stands for workstation no 2.
For this reason FormActivate and FormDeacivate events are not usable.
>METHOD FormDeactivate( oSender, oCtl ) CLASS TForm2
>
> ::oDbf:Save()
> if oCtl != NIL
> oCtl:oDbf:Load()
> endif
>
>RETURN Nil
I asked how to reread from and write back to the database file only one field
and not all the fields of the actual record. I'm missing a method like oDatafield:Save()
BTW for the 'normal' editcontrols I'm missing a SetGet-function too. In my
humble opinion it would be very good if there were the possibility in the
IDE to link a control with a variable which would be actualized by the control.
Now I have to write the code for every control to read the value from the
variable at onEnter and write it back at onExit.

>BTW, this only works with the new file I attach to this message because
some
>modifications have been done in order to work properly due the following
>problems:
>
>a) The update of oDataField buffers was done on method Update(), now is
>moved to Save() method
>
>b) Load() method did not do a GOTO(RECNO()) operation to force a reread
of
>RDD internal buffers
>
>c) Load() method did not refresh any linked control
>
Regards
Ingo

[Ingo Junge-Herrmann]

Ignacio,
sorry you misunderstood me again.
>OnExit and OnEnter are only triggered when changing the focus on the SAME
>form, so you better use the events OnActivate or OnDeactivate which is
>triggered every time the FORM is activated:
No, please pay attention that I'm talking about xBase apps which are running
in a network on different workstations at the same time. Therefore it is
necessary that all the controls in a form wich are holding datas from the
shared database file will be actualized when the user enter them.
Therefore the question is, how to reread the data from the field which is
linked with the control when the control gets the focus and how to write
modified values back when it looses the focus.
Only to show you what the problem is the sample uses two forms. Form1 stands
for workstation no 1 and Form2 stands for workstation no 2.
For this reason FormActivate and FormDeacivate events are not usable.
>METHOD FormDeactivate( oSender, oCtl ) CLASS TForm2
>
> ::oDbf:Save()
> if oCtl != NIL
> oCtl:oDbf:Load()
> endif
>
>RETURN Nil
I asked how to reread from and write back to the database file only one field
and not all the fields of the actual record. I'm missing a method like oDatafield:Save()
BTW for the 'normal' editcontrols I'm missing a SetGet-function too. In my
humble opinion it would be very good if there were the possibility in the
IDE to link a control with a variable which would be actualized by the control.
Now I have to write the code for every control to read the value from the
variable at onEnter and write it back at onExit.

>BTW, this only works with the new file I attach to this message because
some
>modifications have been done in order to work properly due the following
>problems:
>
>a) The update of oDataField buffers was done on method Update(), now is
>moved to Save() method
>
>b) Load() method did not do a GOTO(RECNO()) operation to force a reread
of
>RDD internal buffers
>
>c) Load() method did not refresh any linked control
>
Regards
Ingo

[ignacio]

Ingo,
I send you your sample corrected, so you can see how it is working as
expected.
> No, please pay attention that I'm talking about xBase apps which are
> running
> in a network on different workstations at the same time. Therefore it is
> necessary that all the controls in a form wich are holding datas from the
> shared database file will be actualized when the user enter them.
OnEnter and OnExit are not valid in any case since they are ONLY TRIGGERED
when navigating on the same form. If you need a more accurate method that
the proposed of OnActivate and OnDeactivate I suggest you use a timer, or a
confjuntion of all the events you want plus the timer. It depends on how
accurate you want to be.
> Therefore the question is, how to reread the data from the field which is
> linked with the control when the control gets the focus and how to write
> modified values back when it looses the focus.
Again: oDataSet:Load() and oDataSet:Save()
> I asked how to reread from and write back to the database file only one
> field
> and not all the fields of the actual record. I'm missing a method like
> oDatafield:Save()
Use oDataSet:Save() instead
> BTW for the 'normal' editcontrols I'm missing a SetGet-function too. In my
> humble opinion it would be very good if there were the possibility in the
> IDE to link a control with a variable which would be actualized by the
> control.
> Now I have to write the code for every control to read the value from the
> variable at onEnter and write it back at onExit.
DataControls is a step beyond that classic Clipper or F*vewin approach of
holding data. But even without using DataControls at all, there is no need
to use any extra variable, its even useless the use of variables to hold the
data since the use of the controls directly is by far more handy because all
the control are in scope since are members of the form class, but with
variables you need to pass them all to any function or method you may call.
Xailer proposes new programming mechanisms that may be difficult at the
beginning, but I am sure you will be happy with them on a very short time.
Regards,


Attached files testload.zip (3.1 KB)Â

[InvalidAccount]

Ingo,
I send you your sample corrected, so you can see how it is working as
expected.
> No, please pay attention that I'm talking about xBase apps which are
> running
> in a network on different workstations at the same time. Therefore it is
> necessary that all the controls in a form wich are holding datas from the
> shared database file will be actualized when the user enter them.
OnEnter and OnExit are not valid in any case since they are ONLY TRIGGERED
when navigating on the same form. If you need a more accurate method that
the proposed of OnActivate and OnDeactivate I suggest you use a timer, or a
confjuntion of all the events you want plus the timer. It depends on how
accurate you want to be.
> Therefore the question is, how to reread the data from the field which is
> linked with the control when the control gets the focus and how to write
> modified values back when it looses the focus.
Again: oDataSet:Load() and oDataSet:Save()
> I asked how to reread from and write back to the database file only one
> field
> and not all the fields of the actual record. I'm missing a method like
> oDatafield:Save()
Use oDataSet:Save() instead
> BTW for the 'normal' editcontrols I'm missing a SetGet-function too. In my
> humble opinion it would be very good if there were the possibility in the
> IDE to link a control with a variable which would be actualized by the
> control.
> Now I have to write the code for every control to read the value from the
> variable at onEnter and write it back at onExit.
DataControls is a step beyond that classic Clipper or F*vewin approach of
holding data. But even without using DataControls at all, there is no need
to use any extra variable, its even useless the use of variables to hold the
data since the use of the controls directly is by far more handy because all
the control are in scope since are members of the form class, but with
variables you need to pass them all to any function or method you may call.
Xailer proposes new programming mechanisms that may be difficult at the
beginning, but I am sure you will be happy with them on a very short time.
Regards,


Attached files testload.zip (3.1 KB)Â

[Ingo Junge-Herrmann]

Ignacio,
thank you for the answer.
Using the Activate and Deactivate events are improper to actualize the datacontrols
of a form wich is active on different workstations. I see there is only the
possibility to use the timer for rereading datas from disk when the form
is active over a longer time or to go back to the old practice without using
Xailer's DataControls.
I thought it would be very simple with Xailer's DataControls to look if
the data would be modified by another workstation in the meantime and reread
the data if necessary when the focus moves to the next control. But unfortunatly
it isn't so.
Regards
Ingo

[Ingo Junge-Herrmann]

Ignacio,
thank you for the answer.
Using the Activate and Deactivate events are improper to actualize the datacontrols
of a form wich is active on different workstations. I see there is only the
possibility to use the timer for rereading datas from disk when the form
is active over a longer time or to go back to the old practice without using
Xailer's DataControls.
I thought it would be very simple with Xailer's DataControls to look if
the data would be modified by another workstation in the meantime and reread
the data if necessary when the focus moves to the next control. But unfortunatly
it isn't so.
Regards
Ingo

[ignacio]

Ingo,
> Using the Activate and Deactivate events are improper to actualize the
> datacontrols
I believe I already answered this. Sorry if I did not explain myself
correctly.
> is active over a longer time or to go back to the old practice without
> using
> Xailer's DataControls.
You are completely missing the point. you mistake events with DataControls.
If you feel better with old approach use it. Xailer does not force the use
of DataControls.
The only question you sould answer yourself is:
Which event do I trap to update the data? or Should I use a timer for the
job?
And sorry I do not have a answer for that it depends on how accurate you
want to be AND exactly when you want to update that information. But for
sure, even if you DO NOT USE DataControls I am afraid you will have to
answer this same question.
> I thought it would be very simple with Xailer's DataControls to look if
> the data would be modified by another workstation in the meantime and
> reread
> the data if necessary when the focus moves to the next control. But
> unfortunatly
> it isn't so.
Sorry, but some work on your side is needed but not too much. We can not put
that overload on the DataControls engine.
This code updates the datacontrol when it receives focus:
METHOD DB1Enter( oSender, oNextCtl ) CLASS TForm1
::oDbf:Load()
RETURN Nil
Regards,
"Ingo Junge-Herrmann" <[email=XPRO-0031BA74-01@10.0.0.11]XPRO-0031BA74-01@10.0.0.11[/email]> escribió en el mensaje
news:43d5fb5b$[email=1@ozsrvnegro.ozlan.local...]1@ozsrvnegro.ozlan.local...[/email]
>
> Ignacio,
>
> thank you for the answer.
>
> Using the Activate and Deactivate events are improper to actualize the
> datacontrols
> of a form wich is active on different workstations. I see there is only
> the
> possibility to use the timer for rereading datas from disk when the form
> is active over a longer time or to go back to the old practice without
> using
> Xailer's DataControls.
>
> I thought it would be very simple with Xailer's DataControls to look if
> the data would be modified by another workstation in the meantime and
> reread
> the data if necessary when the focus moves to the next control. But
> unfortunatly
> it isn't so.
>
> Regards
>
> Ingo
>
>
>

[InvalidAccount]

Ingo,
> Using the Activate and Deactivate events are improper to actualize the
> datacontrols
I believe I already answered this. Sorry if I did not explain myself
correctly.
> is active over a longer time or to go back to the old practice without
> using
> Xailer's DataControls.
You are completely missing the point. you mistake events with DataControls.
If you feel better with old approach use it. Xailer does not force the use
of DataControls.
The only question you sould answer yourself is:
Which event do I trap to update the data? or Should I use a timer for the
job?
And sorry I do not have a answer for that it depends on how accurate you
want to be AND exactly when you want to update that information. But for
sure, even if you DO NOT USE DataControls I am afraid you will have to
answer this same question.
> I thought it would be very simple with Xailer's DataControls to look if
> the data would be modified by another workstation in the meantime and
> reread
> the data if necessary when the focus moves to the next control. But
> unfortunatly
> it isn't so.
Sorry, but some work on your side is needed but not too much. We can not put
that overload on the DataControls engine.
This code updates the datacontrol when it receives focus:
METHOD DB1Enter( oSender, oNextCtl ) CLASS TForm1
::oDbf:Load()
RETURN Nil
Regards,
"Ingo Junge-Herrmann" <[email=XPRO-0031BA74-01@10.0.0.11]XPRO-0031BA74-01@10.0.0.11[/email]> escribió en el mensaje
news:43d5fb5b$[email=1@ozsrvnegro.ozlan.local...]1@ozsrvnegro.ozlan.local...[/email]
>
> Ignacio,
>
> thank you for the answer.
>
> Using the Activate and Deactivate events are improper to actualize the
> datacontrols
> of a form wich is active on different workstations. I see there is only
> the
> possibility to use the timer for rereading datas from disk when the form
> is active over a longer time or to go back to the old practice without
> using
> Xailer's DataControls.
>
> I thought it would be very simple with Xailer's DataControls to look if
> the data would be modified by another workstation in the meantime and
> reread
> the data if necessary when the focus moves to the next control. But
> unfortunatly
> it isn't so.
>
> Regards
>
> Ingo
>
>
>