FORM LOAD
FORM LOAD ( {aTable ;} form {; formData}{; *} )
| Parâmetro | Tipo | Descrição | |
|---|---|---|---|
| aTable | Tabela | → | Table form to load (if omitted, load a project form) |
| form | Text, Object | → | Name (string) of form (project or table), ora POSIX path (string) to a .json file describing the form, or an object describing the form to open |
| formData | Object | → | Data to associate to the form |
| * | Operador | → | If passed = command applies to host database when it is executed from a component (parameter ignored outside of this context) |
This command is not thread-safe, it cannot be used in preemptive code.
Descrição
The FORM LOAD command is used to load the form in memory in the current process along with formData (optional) in order to print its data or parse its contents.The FORM LOAD command is used to load the form in memory in the current process along with formData (optional) in order to print its data or parse its contents.The FORM LOAD command is used to load the form in memory in the current process along with formData (optional) in order to print its data or parse its contents. There can only be one current form per process.
In the form parameter, you can pass:
- the name of a form, or
- the path (in POSIX syntax) to a valid .json file containing a description of the form to use, or
- an object containing a description of the form.
When the command is executed from a component, it loads the component forms by default. If you pass the * parameter, the method loads the host database forms.
formData
Optionally, you can pass parameters to the form using either the formData object or the form class object automatically instantiated by 4D if you have associated a user class to the form. Any properties of the form data object will then be available from within the form context through the Form command. Any properties of the form data object will then be available from within the form context through the Form command.
Para obter informações detalhadas sobre o objeto de dados do formulário, consulte o comando DIALOG.
Printing data
In order to be able to execute this command, a print job must be opened beforehand using the OPEN PRINTING JOB command. The OPEN PRINTING JOB command makes an implicit call to the FORM UNLOAD command, so in this context it is necessary to execute FORM LOAD. Once loaded, this form becomes the current printing form. All the object management commands, and in particular the Print object command, work with this form.
If a printing form has already been loaded beforehand (via a previous call to the FORM LOAD command), it is closed and replaced by form. You can open and close several project forms in the same print session. Changing the printing form via the FORM LOAD command does not generate page breaks. It is up to the developer to manage page breaks.
Only the On Load form event is executed during the opening of the project form, as well as any object methods of the form. Other form events are ignored. O evento formulário On Unload é executado no final da impressão.
To preserve the graphic consistency of forms, it is recommended to apply the "Printing" appearance property regardless of the platform.
The current printing form is automatically closed when the CLOSE PRINTING JOB command is called.
Parsing form contents
This consists in loading an off-screen form for parsing purposes. To do this, just call FORM LOAD outside the context of a print job. In this case, form events are not executed.
FORM LOAD can be used with the FORM GET OBJECTS and OBJECT Get type commands in order to perform any type of processing on the form contents. You must then call the FORM UNLOAD command in order to release the form from memory.
Note that in all cases, the form on screen remains loaded (it is not affected by the FORM LOAD command) so it is not necessary to reload it after calling FORM UNLOAD.
Reminder: In the off-screen context, do not forget to call FORM UNLOAD to avoid any risk of memory overflow.
Exemplo 1
Calling a project form in a print job:
OPEN PRINTING JOB
FORM LOAD("print_form")
// execution of events and object methods
Exemplo 2
Calling a table form in a print job:
OPEN PRINTING JOB
FORM LOAD([People];"print_form")
// execution of events and object methods
Exemplo 3
Parsing of form contents to carry out processing on text input areas:
FORM LOAD([People];"my_form")
// selection of form without execution of events or methods
FORM GET OBJECTS(arrObjNames;arrObjPtrs;arrPages;*)
For($i;1;Size of array(arrObjNames))
If(OBJECT Get type(*;arrObjNames{$i})=Object type text input)
//… processing
End if
End for
FORM UNLOAD //do not forget to unload the form
Exemplo
The following example returns the number of objects on a JSON form:
ARRAY TEXT(objectsArray;0) //sort form items into arrays
ARRAY POINTER(variablesArray;0)
ARRAY INTEGER(pagesArray;0)
FORM LOAD("/RESOURCES/OutputForm.json") //load the form
FORM GET OBJECTS(objectsArray;variablesArray;pagesArray;Form all pages+Form inherited)
ALERT("The form contains "+String(size of array(objectsArray))+" objects") //return the object count
the result shown is:
Exemplo 2
You want to print a form containing a list box. During the on load event, you want the contents of the list box to be modified.
1. In the printing method, you write:
var $formData : Object
var $over : Boolean
var $full : Boolean
OPEN PRINTING JOB
$formData:=New object
$formData.LBcollection:=New collection()
... //fill the collection with data
FORM LOAD("GlobalForm";$formData) //store the collection in $formData
$over:=False
Repeat
$full:=Print object(*;"LB") // the datasource of this "LB" listbox is Form.LBcollection
LISTBOX GET PRINT INFORMATION(*;"LB";lk printing is over;$over)
If(Not($over))
PAGE BREAK
End if
Until($over)
FORM UNLOAD
CLOSE PRINTING JOB
2. In the form method, you can write:
var $o : Object
Case of
:(Form event code=On Load)
For each($o;Form.LBcollection) //LBcollection is available
$o.reference:=Uppercase($o.reference)
End for each
End case
Veja também
Current form name
FORM UNLOAD
LISTBOX GET OBJECTS
OBJECT Get type
Print object