Progress
Language Reference
DEFINE BROWSE Statement
Defines and creates either a static read-only browse widget or a static updateable browse widget.
SYNTAX
NEW SHARED
Defines a browse widget that can be used by other procedures. When the procedure containing this statement ends, the browse is no longer available.
You cannot define a SHARED or NEW SHARED browse widget in a persistent procedure. If you do, Progress raises ERROR on the RUN statement that creates the procedure.
SHARED
Defines a browse that was created in another procedure with the DEFINE NEW SHARED BROWSE statement.
BROWSE browse-name
Identifies the name of the browse you want to define for the query.
QUERY query-name
The name of the query to browse. You must have previously defined or opened the query.
[ SHARE-LOCK | EXCLUSIVE-LOCK | NO-LOCK ]
Specifies the locking mode for records retrieved by the browse widget. The default locking mode is NO-LOCK. To control locking during preselection for a query associated with a browse widget, use the SHARE-LOCK, EXCLUSIVE-LOCK, or NO-LOCK option in the OPEN QUERY statement that opens the query.
NO-WAIT
Specifies not to wait for a record that is currently locked by another process. Instead, the record in conflict will be made available in NO-LOCK mode and the LOCKED function for that record will return TRUE.
DISPLAY column-list
Specifies the column items to display in the browse. Note that the column-list cannot contain widgets other than fill-ins and the column-list cannot contain SKIP options.
expression
A field name, variable, constant, or expression to display in each iteration of the browse frame.
column-format-phrase
Specifies the format for a value displayed in the browse. The column-format-phrase is a subset of the Format phrase.
WIDTH n
Specify a width for the browse column. n represents a multiplier of the average character width of the column font. Specifying a width smaller than the format string creates a scrolling browse cell, if the column is updateable.
For more information on FORMAT strings and label options, see the Format Phrase reference entry. The column and label color and font options work like those specified in the browse-options-phrase. If color or fonts are specified with this phrase, they only affect the specific column and override similar options specified in the browse-options-phrase.
@base-field
The base-field must be the name of a field or variable; it cannot be an expression or constant.
Progress reserves enough space for the base-field to hold the longest format displayed there. All right-justified fields (numeric fields that do not use side labels) are right justified within the reserved area.
To determine the format to use for displaying the expression at the base-field, Progress looks at the following and uses the first format that applies:
- An explicit format used with the expression
- If the expression is a character string constant, a format that accommodates that string
- If the data type of the expression matches that of the base-field, the format of the base-field
- The standard format of the expression as if it were displayed without a base-field
DISPLAY record
Specifies the record you want to display. If you specify a record, all fields from the record are displayed unless you use the EXCEPT option to eliminate specific fields.
See the Record Phrase reference entry for more information.
EXCEPT field . . .
Specifies fields that are not displayed in the browse. You can use the EXCEPT option only if you specify a record name in the DISPLAY option.
browse-enable-phrase
Specifies which fields in the column-list are enabled for input.
List each field or variable from the column-list that you want enabled. Specify ALL to specify every item in the column-list. Use the EXCEPT option to eliminate specific items when you use the ALL option. For each field or variable, you can also specify custom help and validation, as shown in the next two entries.
HELP string
Represents a character string that you want to display whenever the user enters the frame field for the field or variable. When the user leaves the frame field, Progress removes the help string from the message area. You must enclose the string in quotation marks (
""
).VALIDATE ( condition, msg-expression )
Specifies an expression that you want to validate against the data entered into a the browse cell. The condition is a Boolean expression (a constant, field name, variable name, or expression) whose value is TRUE or FALSE.
When you use the VALIDATE option to validate a specific cell, any reference to that cell in condition is assumed to be the new input value. For example, in the browse-enable phrase below, the promise-date that is compared to the order-date is the new user input, not the existing data.
To validate a new value against another new value, use the INPUT qualifier, as shown below.
If the value of condition is FALSE, use msg-expression to display a specific message. You must enclose msg-expression in quotation marks (
""
).Progress processes validation criteria whenever the user attempts to leave the browse cell. If the cell value is not valid, Progress displays msg-expression in the message area, causes the terminal to beep, and does not advance out of the browse cell.
If the user tabs to a cell, make no changes, and leave the cell, Progress does not process the validation criteria specified with the VALIDATE option until the you press GO (F1). If the user presses ENDKEY or END-ERROR, or an error occurs, Progress does not test the validation criteria specified with the VALIDATE option.
If the input source for the procedure is a table, Progress validates each input field (except those with a value of "-"). If the result of the validation is FALSE, msg-expression is displayed and Progress treats the validation as an error.
To suppress the Data Dictionary validation criteria for a cell, use this VALIDATE option.
AUTO-RETURN
Indicates whether Progress should behave as if the user pressed the RETURN key.when the user enters the last allowable character in a browse cell of the specified browse-column.
DISABLE-AUTO-ZAP
Indicates whether Progress should ignore the value of the browse-column’s AUTO-ZAP attribute and assume it is FALSE.
browse-options-phrase
Specifies options that affect the browse widget as a whole. The options affect both the layout and the function of the browse widget. (Note that you cannot include aggregate-phrases (TOTAL, MIN, etc.) in this phrase.) This is the syntax for browse-options-phrase.
[ constant ] DOWN [ WIDTH width ]
The constant value is the number of rows displayed in the browse and must be at least 2. You can optionally specify the width of the browse, where width is the width of the browse in character units.
A browse-options-phrase must contain a DOWN option or a size-phrase.
size-phrase
Specifies the outer size of the browse border. When this option is used instead of the DOWN option, Progress determines the number of rows that can be displayed in the browse. This is the syntax for size-phrase.
For more information on size-phrase, see the SIZE Phrase reference entry.
A browse-options-phrase must contain a DOWN option (optionally with a WIDTH option) or a size-phrase.
FGCOLOR expression
Specifies the foreground color for the browse in graphical environments, but not the label foreground color. The value of expression must be an integer value that specifies an entry in the color table. This option is ignored in character environments.
BGCOLOR expression
Specifies the background color for the browse in graphical environments. The value of expression must be an integer value that specifies an entry in the color table. This option is ignored in character environments.
DCOLOR expression
Specifies the display color for the browse in character environments. The value of expression must be an integer value that specifies an entry in the color table. This option is ignored in graphical environments.
PFCOLOR expression
Specifies the prompt color for the browse in character environments. The value of expression must be an integer value that specifies an entry in the color table. This option is ignored in graphical environments.
LABEL-FONT constant
Specifies the font of the browse labels.
LABEL-DCOLOR expression
Specifies the display color for the browse labels in character environments. The value of expression must be an integer value that specifies an entry in the color table. This option is ignored in graphical environments.
LABEL-FGCOLOR expression
Specifies the foreground color for the browse labels in graphical environments. The value of expression must be an integer value that specifies an entry in the color table. This option is ignored in character environments.
LABEL-BGCOLOR expression
Specifies the background color for the browse labels in graphical environments. The value of expression must be an integer value that specifies an entry in the color table. This option is ignored in character environments.
[ MULTIPLE | SINGLE ]
Specifies whether multiple rows can be selected from the browse or only a single row at one time. The default is SINGLE.
[ SEPARATORS | NO-SEPARATORS ]
Specifies whether row and column separators are displayed within the browse. The default is NO-SEPARATORS.
NO-ASSIGN
Disables automatic writes on new data in an updateable browse. If this option is not specified, data entered into an updateable browse is assigned on any action that results in a ROW-LEAVE event. This option is intended for use with user-defined triggers on the ROW-LEAVE event. Essentially, when this option is specified, all data assignments by way of the updateable browse are up to the 4GL programmer.
In the above example, the code looks for a special case where automatic database writes are not desirable and prevents them. The body of the trigger handles other processing before proceeding to commit the changes. First the trigger refinds the current customer record and then uses the CURRENT-CHANGED function to see if it has changed while the user was updating the browse cells. If it has not changed, the changes are committed. If it has changed, the trigger would handle that condition, too.
Note that an ASSIGN statement with the INPUT BROWSE option can be mixed with other assignment types, as shown below.
NO-ROW-MARKERS
By default, an updateable browse displays row markers, which allow the user to select currently displayed rows in an updateable browse widget. This option prevents row markers from being displayed.
NO-LABELS
Does not display labels above the columns of the browse.
NO-BOX
Does not display a box around the browse. If you do not use this option, Progress displays a box around the data you are displaying.
If you are sending data to a device other than a terminal and you do not use this option, Progress omits the sides and bottom line of the box and replaces the top line with blanks.
FONT constant
Specifies the font of the browse. The title and labels also use this font, unless otherwise specified.
title-phrase
Displays a title as part of the top line of the box around the browse.
The title-string is a constant, field name, variable name, or expression whose result is a character value. The expression is the value you want to display as a title. If title-string is a constant character string, it must be surrounded by quotes (
""
). Progress automatically centers title-string in the top line of the browse box.You can use the BGCOLOR and FGCOLOR options to specify the background and foreground color of the title under a graphical user interface. You can use the DCOLOR option to specify the color of the title under a character user interface.
NO-VALIDATE
Tells Progress to ignore the validations conditions in the schema for all fields in the browse.
Since browses do not inherit the NO-VALIDATE option from a parent frame, if you want a browse to have this option, you must specify it explicitly.
NO-SCROLLBAR-VERTICAL | SCROLLBAR-VERTICAL
Indicates whether the browse displays a vertical scrollbar. The default is for the vertical scrollbar to appear.
ROW-HEIGHT-CHARS | ROW-HEIGHT-PIXELS row-height
An INTEGER representing the row height in characters or pixels.
This option applies to graphical interfaces only.
The ROW-HEIGHT-CHARS and ROW-HEIGHT-PIXELS options let you specify the browse’s row height, in either characters or pixels.
EXPANDABLE
If you set a browse’s EXPANDABLE attribute to TRUE, Progress extends the right-most browse-column horizontally to the browse’s right edge, if necessary, to cover any white space that might appear there — unless you explicitly set the width of the right-most browse-column using the WIDTH-CHARS or WIDTH-PIXELS attribute. The expansion of the right-most browse-column might occur anytime the browse or another browse-column is resized.
The right-most browse-column expands only when there is no horizontal scroll bar. This is because when there is a horizontal scroll bar, no white space appears between the right edge of the right-most browse-column and the right edge of the browse.
NO-AUTO-VALIDATE
Tells Progress to compile into the code all relevant validations it finds in the Progress Data Dictionary, but to run the validations only when the code for a browse or for a browse-column specifically invokes the VALIDATE() method.
CONTEXT-HELP-ID expression
An integer value that specifies the identifier of the help topic for this browse in a help file specified at the session, window, or dialog box level using the CONTEXT-HELP-FILE attribute.
DROP-TARGET
Indicates whether the user can drop a file onto the object.
TOOLTIP tooltip
Allows you to define a help text message for a browse widget. Progress automatically displays this text when the user pauses the mouse pointer over a browse widget for which a ToolTip is defined. You can add or change the TOOLTIP option at any time.
If TOOLTIP is set to “” or ? (the unknown value), then the ToolTip is removed from the browse. No ToolTip is the default. ToolTips are supported in Windows only.
EXAMPLESThis procedure sets up a read-only browse widget for the customer table. The browse displays the Cust-num and Name fields. A separate frame, f2, displays more information on the currently chosen customer.
The VALUE-CHANGED event occurs each time the user selects a row within the browse widget. The associated database record is automatically placed into the record buffer. The trigger on the VALUE-CHANGED event displays that record in frame f2.
The APPLY statement causes the first Customer record to display before the user selects a record.
The second example sets up an updateable browse that displays some fields from the customer table. Select a row marker to select a row. Select a cell to edit it. Select a column label to initiate a search.
The trigger on ROW-LEAVE is only necessary because the NO-ASSIGN option prevents automatic commitment of the data when the user leaves a row.NOTES
- The vertical scrollbar is displayed with the browse by default in Windows interfaces. It may be removed by setting the SCROLLBAR-VERTICAL attribute to FALSE or by specifying NO-SCROLLBAR-VERTICAL in the DEFINE BROWSE statement. If the horizontal scrollbar is needed, it is provided by default.
- The vertical scrollbar thumb size reflects the percentage of rows that are displayed in the viewport relative to the number of rows in the results list. If all the rows have not yet been read into the results list, the Progress 4GL uses the MAX-DATA-GUESS attribute to estimate the total size.
- You must put the browse into a frame on the same procedure level on which the browse is defined. For example, you cannot define a browse in an outer procedure and then display it in a frame defined within an internal procedure.
- You cannot display a browse widget in a down frame. Progress automatically converts any frame containing a browse to a 1 down frame.
- You can modify the field values displayed in the current iteration of a browse by using the WITH BROWSE option of the DISPLAY statement.
- The browse widget has built-in support for the HOME, END, PAGE-UP, and PAGE-DOWN key functions.
- Progress treats the query associated with a browse as a scrolling query. You do not have to specify SCROLLING in the DEFINE QUERY statement.
- When you execute an OPEN QUERY or REPOSITION statement for the query associated with the browse, the browse is automatically adjusted to remain in sync with the query. However, when you execute a GET statement, the browse is not adjusted. You can use the GET statement to perform background processing without affecting the browse, but you must execute a REPOSITION statement to put the query and browse back in sync.
- The record locking behavior specified for a query in the DEFINE BROWSE statement overrides the record locking behavior specified with the OPEN QUERY statement. The default record locking behavior of a browse widget is NO-LOCK. The default record locking behavior of a query defined with the OPEN QUERY statement is SHARE-LOCK. If you define a query and a browse widget for the query without explicitly defining record locking behavior, the query will have the NO-LOCK behavior.
- For an updateable browse, Progress re-gets the record with a SHARE-LOCK when the user first edits a row, if it initially has a NO-LOCK. The user then can make changes to the updateable cells in the row. When the user leaves a row with changes (moves to a new row or another widget), Progress starts a transaction and gets the record with EXCLUSIVE-LOCK and NO-WAIT. If Progress gets the record, the record is updated, the record is disconnected (removes the lock), the transaction ends, and the lock is downgraded to its original status. If the get record with EXCLUSIVE-LOCK fails, the transaction is backed out, an error message is displayed, and focus remains with the edited browse row with the changed data. To redisplay the original data, use the DISPLAY...WITH BROWSE statement.
- All LEAVE triggers for a browse row execute before the row changes are committed. If the LEAVE trigger returns a NO-APPLY, the changes are not committed.
- It is also possible to use an updateable browse to add new records and delete old ones. For a complete discussion of these techniques, see the browse chapter in the Progress Programming Handbook .
- Browse widgets on Windows have user search capabilities. Special events allow the programmer to extend these capabilities. For a complete discussion of these techniques, see the chapter on database access in the Progress Programming Handbook .
- When an updateable browse enters edit mode, all selected records are deselected. Essentially, a browse in edit mode ignores multiple selections.
- The ADD-CALC-COLUMN, ADD-COLUMNS-FROM and ADD-LIKE-COLUMN methods may be used on a static browse to add a dynamic browse column. If a dynamic browse column in a static browse is made updateable, the browse is changed to a NO-ASSIGN browse and the 4GL programmer becomes responsible for any database update associated with it.
- The browse’s QUERY attribute can now be set to the UNKNOWN value. If this is done, all browse-columns are removed.
- The browse’s QUERY attribute can now be changed to any query. Previously, the new query had to have the same underlying fields as the original query. If the new query is different, all browse columns are removed. You must specify new columns with the ADD-CALC-COLUMN, ADD-COLUMNS-FROM, and ADD-LIKE-COLUMN methods.
SEE ALSO
ADD-CALC-COLUMN() Method, ADD-COLUMNS-FROM( ) Method, ADD-LIKE-COLUMN( ) Method, CLOSE QUERY Statement, CREATE BROWSE Statement, CURRENT-CHANGED Function, CURRENT-RESULT-ROW Function, DEFINE QUERY Statement, DISPLAY Statement, FIND Statement, Format Phrase, Frame Phrase, GET Statement, NUM-RESULTS Function, OPEN QUERY Statement, RUN Statement
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