__Run()

Template

Procedure

Name

__Run()

Category

API

Subcategory

Environment

Oneliner

Run an external program.

Syntax

      __Run( <cCommand> )

Arguments

<cCommand> Command to execute.

Description

This command runs an external program. Ensure that you have enough free memory to be able to run the external program. Do not use it to run ‘Terminate and Stay Resident’ programs (in case of MS-DOS) since that causes several problems.

Note: This function is what the RUN command preprocesses into. It is considered bad form to use this function directly. Use the RUN command instead.

Examples

      __Run( "edit " + cMyTextFile )    // Runs an external editor
      __Run( "command" )                // Gives a OS shell

Compliance

Clipper

Platforms

All

Files

Library is core

Seealso

RUN

MENU TO

MENU TO

Invoked a menu defined by set of @…PROMPT

Syntax

      MENU TO <cVariable>

Arguments

<cVariable> is a character string that contain the name of the variable to hold the menu choices, if this variable does not exist a PRIVATE variable with the name <cVariable> would be created to hold the result.

Description

Menu To() invoked the menu define by previous __AtPrompt() call and display a highlight bar that the user can move to select an option from the menu. If <cVariable> does not exist or not visible, a PRIVATE variable named <cVariable> is created and hold the current menu selection. If there is a variable named <cVariable>, its value is used to select the first highlighted item.

Menu prompts and messages are displayed in current Standard color, highlighted bar is displayed using current Enhanced color.

Pressing the arrow keys move the highlighted bar. When a menu item is highlighted the message associated with it is displayed on the line specified with SET MESSAGE. If SET WRAP is ON and the user press UP arrow while on the first selection the last menu item is highlighted, if the user press Down arrow while on the last item, the first item is highlighted.

Following are active keys that handled by Menu To:

       key            Meaning
       -------------- ---------------------------------
       Up             Move to previous item
       Down           Move to next item
       Left           Move to previous item
       Right          Move to next item
       Home           Move to the first item
       End            Move to the last item
       Page-Up        Select menu item, return position
       Page-Down      Select menu item, return position
       Enter          Select menu item, return position
       Esc            Abort selection, return 0
       First letter   Select next menu with the same first letter,
                      return this item position.

Upon exit the cursor is placed at MaxRow()-1, 0 Menu To can be nested without loosing the previous prompts.

MENU TO command is preprocessed into __MenuTo() function during compile time.

Examples

      // display menu item on each screen corner and let user select one
      CLS
      SET MESSAGE TO MaxRow() / 2 CENTER
      SET WRAP ON
      @ 0           , 0             PROMPT "1. Upper left"   MESSAGE " One "
      @ 0           , MaxCol() - 16 PROMPT "2. Upper right"  MESSAGE " Two "
      @ MaxRow() - 1, MaxCol() - 16 PROMPT "3. Bottom right" MESSAGE "Three"
      @ MaxRow() - 1, 0             PROMPT "4. Bottom left"  MESSAGE "Four "
      MENU TO nChoice
      SetPos( MaxRow() / 2, MaxCol() / 2 - 10 )
      IF nChoice == 0
         ?? "Esc was pressed"
      ELSE
         ?? "Selected option is", nChoice
      ENDIF

Compliance

Clipper

Seealso

@…PROMPT, ACHOICE(), SET MESSAGE, SET INTENSITY, SET WRAP, __ATPROMPT()

AChoice()

 

ACHOICE()

Allows selection of an element from an array

Syntax

      ACHOICE(<nTop>, <nLeft>, <nBottom>, <nRight>,;
              <acMenuItems>, [<alSelableItems> | <lSelableItems>],;
              [<cUserFunction> | <bUserBlock>], [<nInitialItem>],;
              [<nWindowRow>]) --> nPosition

Arguments

<nTop> – topmost row used to display array (default 0)

<nLeft> – leftmost row used to display array (default 0)

<nBottom> – bottommost row used to display array (default MaxRow())

<nRight> – rightmost row used to display array (default MaxCol())

<acMenuItems> – the character array of items from which to select

<alSelableItems> – an array of items, either logical or character, which is used to determine if a particular item may be selected. If the type of a given item is character, it is macro evaluated, and the result is expected to be a logical. A value of .T. means that the item may be selected, .F. that it may not. (See next argument: lSelectableItems)

<lSelableItems> – a logical value which is used to apply to all items in acMenuItems. If .T., all items may be selected; if .F., none may be selected. (See previous argument: alSelectableItems) Default .T.

<cUserFunction> – the name of a function to be called which may affect special processing of keystrokes. It is specified without parentheses or parameters. When it is called, it will be supplied with the parameters: nMode, nCurElement, and nRowPos. Default NIL.

<bUserBlock> – a codeblock to be called which may affect special processing of keystrokes. It should be specified in the form {| nMode, nCurElemenet, nRowPos | ; MyFunc( nMode, nCurElemenet, nRowPos ) }. Default NIL.

<nInitialItem> – the number of the element to be highlighted as the current item when the array is initially displayed. 1 origin. Default 1.

<nWindowRow> – the number of the window row on which the initial item is to be displayed. 0 origin. Default 0.

Returns

<nPosition> – the number of the item to be selected, or 0 if the selection was aborted.

Description

Allows selection of an element from an array. Please see standard CA-Cl*pper documentation for ACHOICE for additional detail.

Examples

      aItems := { "One", "Two", "Three" }
      nChoice := AChoice( 10, 10, 20, 20, aItems )
      IF nChoice == 0
         ? "You did not choose an item"
      ELSE
         ? "You chose element " + hb_ntos( nChoice )
         ?? " which has a value of " + aItems[ nChoice ]
      ENDIF

Files

Library is rtl

Compliance

Clipper

Seealso

MENU TO

__MenuTo()

Template

Function

Name

__MenuTo()

Category

API

Subcategory

User interface

Oneliner

Invoked a menu defined by set of @…PROMPT

Syntax

      __MenuTo( <bBlock>,  <cVariable> ) --> nChoice

Arguments

<bBlock> is a set/get code block for variable named <cVariable>.

<cVariable> is a character string that contain the name of the variable to hold the menu choices, if this variable does not exist a PRIVATE variable with the name <cVariable> would be created to hold the result.

Returns

__MenuTo() return the number of select menu item, or 0 if there was no item to select from or if the user pressed the Esc key.

Description

__MenuTo() invoked the menu define by previous __AtPrompt() call and display a highlight bar that the user can move to select an option from the menu. If <cVariable> does not exist or not visible, a PRIVATE variable named <cVariable> is created and hold the current menu selection. If there is a variable named <cVariable>, its value is used to select the first highlighted item.

Menu prompts and messages are displayed in current Standard color, highlighted bar is displayed using current Enhanced color.

Pressing the arrow keys move the highlighted bar. When a menu item is highlighted the message associated with it is displayed on the line specified with SET MESSAGE. If SET WRAP is ON and the user press UP arrow while on the first selection the last menu item is highlighted, if the user press Down arrow while on the last item, the first item is highlighted.

Following are active keys that handled by __MenuTo():

       key            Meaning
       -------------  ---------------------------------
       Up             Move to previous item
       Down           Move to next item
       Left           Move to previous item
       Right          Move to next item
       Home           Move to the first item
       End            Move to the last item
       Page-Up        Select menu item,  return position
       Page-Down      Select menu item,  return position
       Enter          Select menu item,  return position
       Esc            Abort selection,  return 0
       First letter   Select next menu with the same first letter, |return this item position.

Upon exit the cursor is placed at MaxRow()-1, 0 __MenuTo() can be nested without loosing the previous  prompts.

MENU TO command is preprocessed into __MenuTo() function during compile time.

Examples

      // display menu item on each screen corner and let user select one
      CLS
      SET MESSAGE TO MaxRow() / 2 CENTER
      SET WRAP ON
      @ 0           ,  0             PROMPT "1. Upper left"   MESSAGE " One "
      @ 0           ,  MaxCol() - 16 PROMPT "2. Upper right"  MESSAGE " Two "
      @ MaxRow() - 1,  MaxCol() - 16 PROMPT "3. Bottom right" MESSAGE "Three"
      @ MaxRow() - 1,  0             PROMPT "4. Bottom left"  MESSAGE "Four "
      MENU TO nChoice
      SetPos( MaxRow() / 2,  MaxCol() / 2 - 10 )
      IF nChoice == 0
         ?? "Esc was pressed"
      ELSE
         ?? "Selected option is",  nChoice
      ENDIF

Compliance

Clipper

Files

Library is core

Seealso

@…PROMPT, AChoice(), SET MESSAGE, SET INTENSITY, SET WRAP, __AtPrompt()

__AtPrompt()

Template

Function

Name

__AtPrompt()

Category

API

Subcategory

User interface

Oneliner

Display a menu item on screen and define a message

Syntax

      __AtPrompt( <nRow>,  <nCol>,  <cPrompt>,  [<xMsg>] ) --> .F.

Arguments

<nRow> is the row number to display the menu <cPrompt>. Value could range from zero to MaxRow().

<nCol> is the column number to display the menu <cPrompt>. Value could range from zero to MaxCol().

<cPrompt> is the menu item character string to display.

<xMsg> define a message to display each time this menu item is highlighted. <xMsg> could be a character string or code block that is evaluated to a character string. If <xMsg> is not specified or of the wrong type, an empty string (“”) would be used.

Returns

__AtPrompt() always return .F.

Description

With __AtPrompt() you define and display a menu item, each call to __AtPrompt() add another item to the menu, to start the menu itself you should call the __MenuTo() function (MENU TO command). You can define any row and column combination and they will be displayed at the order of definition. After each call to __AtPrompt(), the cursor is placed one column to the right of the last text displayed, and Row() and Col() are updated.

@…PROMPT command is preprocessed into __AtPrompt() function during compile time.

Examples

      // display a two line menu with status line at the bottom
      // let the user select favorite day
      SET MESSAGE TO 24 CENTER
      @ 10,  2 PROMPT "Sunday" MESSAGE "This is the 1st item"
      @ 11,  2 PROMPT "Monday" MESSAGE "Now we're on the 2nd item"
      MENU TO nChoice
      DO CASE
      CASE nChoice == 0           // user press Esc key
         QUIT
      CASE nChoice == 1           // user select 1st menu item
         ? "Guess you don't like Mondays"
      CASE nChoice == 2           // user select 2nd menu item
         ? "Just another day for some"
      ENDCASE

Compliance

C (menu)

Files

Library is core

Seealso

AChoice(), MENU TO, SET MESSAGE, SET INTENSITY, SET WRAP, __MenuTo()

@…PROMPT

@…PROMPT

Display a menu item on screen and define a message

Syntax

      @ <nRow>, <nCol> PROMPT <cPrompt> [MESSAGE <xMsg>]

Arguments

<nRow> is the row number to display the menu <cPrompt>. Value could range from zero to MaxRow().

<nCol> is the column number to display the menu <cPrompt>. Value could range from zero to MaxCol().

<cPrompt> is the menu item character string to display.

<xMsg> define a message to display each time this menu item is highlighted. <xMsg> could be a character string or code block that is evaluated to a character string. If <xMsg> is not specified or of the wrong type, an empty string (“”) would be used.

Description

With @…Prompt you define and display a menu item, each call to @…Prompt add another item to the menu, to start the menu itself you should call the __MenuTo() function (MENU TO command). You can define any row and column combination and they will be displayed at the order of definition. After each call to @…Prompt, the cursor is placed one column to the right of the last text displayed, and ROW() and COL() are updated.

@…PROMPT command is preprocessed into __AtPrompt() function during compile time.

Examples

      // display a two line menu with status line at the bottom
      // let the user select favorite day
      SET MESSAGE TO 24 CENTER
      @ 10, 2 PROMPT "Sunday" MESSAGE "This is the 1st item"
      @ 11, 2 PROMPT "Monday" MESSAGE "Now we're on the 2nd item"
      MENU TO nChoice
      DO CASE
      CASE nChoice == 0           // user press Esc key
         QUIT
      CASE nChoice == 1           // user select 1st menu item
         ? "Guess you don't like Mondays"
      CASE nChoice == 2           // user select 2nd menu item
         ? "Just another day for some"
      ENDCASE

Compliance

Clipper (menu)

Seealso

ACHOICE(), MENU TO, SET MESSAGE, SET INTENSITY, SET WRAP, __MENUTO()

MEMVAR

MEMVAR

Declares private and public variables and arrays.

Syntax

      MEMVAR <xVar>

Arguments

<xVar> Memory variable Name

Description

This command tells the compiler to resolve any reference to a memory variable designated within this list s if it possessed an explicit memory variable alias with either the M-> or MEMVAR-> prefix.Only those memory variables that do not contain any such explicit are affected by this command. Those memory variabls within macro expansions are not affected by this command.

The MEMVAR declaration must apear before any executable commands;it is similat to the LOCAL, STATIC, FIELD, PARAMETERS, FUNCTION, and PROCEDURE commands statements.

Examples

      MEMVAR y AS NUMERIC
      PROCEDURE Main()
         LOCAL n, lVar

         n := iif( lVar, "A", 3 )
         n := 2
         n := "a"
         n := seconds() + 2
         n := int( seconds() + 2 )
         y := n
         ? y
         RETURN

Tests

      See tests/testwarn.prg for more examples

Compliance

Clipper

Platforms

All

Files

None.

Seealso

LOCAL, STATIC, FIELD, PRIVATE, PUBLIC