ETV Library description page

Compatibility with various BDE alternatives.
TEtvDBGrid, the Lookups property for definition lookup information directly in grid; drag-and-drop, popup menu for grid lookup combo boxes.
Lookup combo box, possibility to switch lookup list dataset;
multi columns filters without describing of event; options to limit list box during incremental search, to show only key field when closed, to accept value then Tab is pressed, to auto complete search, to gray text when ReadOnly; new functions in popup menu.
Switching on/off acceleration for grid and controls.
TEtvDBText, the LookupDataSet, LookupKeyField properties.
EtvConst unit, many default keys and options.
TEtvFilter, Choose records with no one subrecord; properties to tune on various datasets.
TEtvRecordScrollBox, the component for generation of one-record editing window.
TEtvTabSheet, the OnActivate and OnDeactivate events.

Version 3.3

All units are remaked, library has been divided into base package and separate parts, each part can work independently; user may register whole Etv Library or separate its parts;
Etv Library has been tested with Delphi 5.0 Update Pack 1;
FieldQuotes property is added to TEtvFilter and TEtvSortingCombo;
Caption and ExternalInfo properties are added to TEtvFilter and its SubDataSets;
NotUseOldFilter property is added to TEtvFilter;
Quotes parameter is added to AllFieldNames, SortingToDataSet and SortingToSQL procedures;
Value AutoWidth is added to the Options property of TFormDB;
Some bugs have been fixed.

Version 3.2

TEtvDBLookupCombo can change LookupDataSet sorting criteria
Popup menu of TEtvDBLookupCombo has been added
Some bugs have been fixed

Version 3.1

Delphi 5 is now supported
Library can work without BDE, see file Etv.inc
TEtvFilter works with any dataset
Edit Forms Calling Mechanism works with any dataset. The OnEditData event has been added to TEtvDBLookupCombo and TEtvLookField
TotalFont property has been added to the TEtvDBGrid component
StoreLookupData property has been added to the TEtvLookField field for compatibility with different datasets. If TEtvLookField doesn't work with some datasets when StoreLookupData=true, set this property to false. For example, this is required for ADO datasets from Delphi 5. Otherwise set this property to true to increase speed. For example, this works for all descendants of TBDEDataset. If you upgraded from previous versions of Etv library, now all EtvLookField will have StoreLookupData=false.

Components for supporting lookup information

TEtvLookField, TEtvDBLookupCombo, TEtvDBGrid, etc.

The lookup components include lookup combo box, dbgrid, lookup field and other auxiliary components. They allow for the following features:

Display of several fields in the closed lookup combo box and in the grid
Setting filters on the lookup drop-down list
Multi-level lookup combo box with fixed levels and trees
Advanced incremental search with displayed input string; can work with numbers
Calling LookupDataset edit form and getting values from it
Direct editing KeyField in the LookupComboBox and in the Grid
Toggling search/input column
Toggling between lookup dataset sorting criteria
Special lookup field with support of all lookup features, including determination of several fields in the LookupResultField property
Saving lookup information for later use (from lookupResultField and other special properties)
Components for displaying saved lookup information
Defining TFont for any line from lookup drop-down list
Lookup list headers. These display field names or other user-defined information
Automatic choice of input column (for "Number;Text" fields)
Possibility of working inside the TDBCtrlGrid
Possibility of setting values not present in the LookupDataSet
Other properties and options

Grid

TEtvDBGrid is descendant of TDBGrid with:

Powerful lookup fields (see above), supporting all of Etv Lookup features
Multi-line headers, changing number of header rows depending on the column size
"Total" row at the bottom of the grid which can show any information such as column sums, quantity of records, etc.
Fixed list fields
Font and color settings for any cell including in the editing mode
User-defined visibility and sequence of fields in a special dialog window. Some fields may be marked as internal and always-hidden
Possibility to print out a table or one record in the text or graphics mode with title, page setup, numbering, fonts choice, line spacing, etc., as well as to save in a text file
Toggling between keyboard layouts
Records cloning
Generation of one-record editing window
User-defined substitution of controls for any field types. For example, descendant of TDateEdit from RX library may be used as date editor
Other functions and options

Query and filter builder, sorting and search of records

TEtvFilter component allows the end-user to define queries and filters for single datasets and groups of datasets linked as master-detail or differently. It automatically substitutes the dataset for the generated query and vice versa; may set a filter to the dataset in simple cases. Defining conditions in a special dialog window, user may easily define any extracts of information. Information can be saved to stream and to disk. One can create (recommended) one's own procedure for saving information to one's database or anywhere else.
It is simple in use, user needs only to set DataSource and call the Execute method.

TEtvDBSortingCombo component allows to change the order of records in the dataset, including SQL datasets (such as TQuery). The user can define the list of sorting criteria. List of available sorting criteria may be taken from:
- Items property, when property SelfList=true.
- Index list - for the TTable and similar datasets with the IndexFields property or other descendant of TDBDataSet with TableName property (TEtvQuery has that property)
- SortingList property of dataset. Etv datasets have that property, one can define it in one's own datasets.

TEtvFindDlg component can search for records by using sorting fields, including SQL datasets (such as TQuery). It shows a dialog with controls for input of search values. Parameters "Case sensitive" and "Full coincidence" are used. It can look for nearest records.
It is simple in use, user needs only to set DataSource and call the Execute method .

Fixed list fields

These are TEtvListField, TEtvDBCombo and other components for short fixed lists. Text values from the list correspond to smallint values from the database. For example, "small/middle/large" in the application will correspond to "0/1/2" in the database. The user describes text values in the TEtvListField and they are used everywhere.

Edit Forms Calling Mechanism & Base DB Form

Direct calling of edit form for any dataset displayed on a form, transfer of values to the edit form, setting of the dataset position, return of values from the edit form. Most useful for editing lookup datasets.

Definition of "OnEditData" events in the data-aware controls and in the datasets allows to proceed from data to their edit forms (Such events exist in the TEtvDBLookupCombo and TEtvLookField components). Components TEtvDBLookupCombo and TEtvDbGrid can use this event, send current key value (KeyField.Name and KeyField.Value) there, assign the returned value and refresh lookup information. TFormBase form can obtain, use and return these values.

Base Etv DB Form is TFormBase with automatic page generation for editing one record, defining and setting of filters and queries, opening, sorting, searching and refreshing of information, auto calculation of its width by main dataset grid, procedures for quick creation, searching and calling of forms, other properties that can be visible in the Object Inspector at the design-time, other functions and options.

Popup menus

Run-time. Popup menus of data-aware controls contain functions of navigation, records cloning, plus many others depending on the type of controls. Popup menus are auto attached to all etv controls without them; they have fully functional shortcuts. Only one instance of popup menu of each type is created and used for all corresponding controls.

Functions for different controls:

EtvDBLookupCombo. Changing search/input column, toggling between lookup dataset sorting criteria.
DBGrid/EtvDBGrid. fields visibility, printing of current record, printing of grid, one record/grid toggling, calculation of field length.
DBMemo. Copying, inserting, selecting all.
DBRichEdit/EtvDBRichEdit. Font, basic font, paragraph setting; searching/replacing, printing, copying, inserting, selecting all.
DBImage. Copying, inserting, loading from file, saving to file, clearing, scaling.

Design-time.

Dataset popup menu allows:

Data browsing, editing and other operations in the designer
Coping information to clipboard
copying labels from database remarks.
Auto correcting
Info about dataset and its fields

Popup menus of data-aware controls allow proceeding to dataset and datafield. EtvDBLookupCombo also allows width auto sizing, proceeding to lookup dataset.

Choice of active TabSheet is added to Popup menu of TEtvPageControl, as it is complicated seldom from other controls.

Controls for db fields & User controls substitution into the library

Certain library components, such as TEtvFilter, TEtvFindDlg, TFormBase, TEtvDbGrid, etc., while running, create controls (data-aware or data-unaware) for different field types. A set of functions is used to adapt these controls to the fields and attach multifunction popup menus to them.

Creation of controls may be re-determined for any field type, including controls using in the TEtvDbGrid component. For this, the required variable in your project or library should simply be assigned the function of creation. Redefined controls will be used by etv components.

Other components and mechanisms

Etv datasets
- Editing data in design-time; You may call "Base DB form" and edit, sort, search data, get extracts of information there.
- Popup menu in designer consists copying to the clipboard, pumping labels from the database remarks, field auto correction, info about dataset and its fields.
- Checking a mastersource by inserting a record, i.e. master record must exist and if one is in the insert mode it call post.
- Autoincrement fields calculation from Delphi for single user applications.
- Other properties and events
TEtvPageControl+TEtvTabSheet. Turn off the data on inactive pages to increase speed. It can turn off dbaware control from datasource and detail dataset from master. The design-time popup menu allows to choose current TabSheet. TEtvTabSheet has the OnActivate and OnDeactivate events.
Automatic opening/refreshing datasets in the run-time. This mechanism may open datasets in datamodules (not all, optionally) when project opening, opening or refreshing some datasets represented on a form then one become active.
TEtvPrinter and auxiliary components. Printing in the text and graphics mode, output to the file, page setup, numbering, fonts choice, including text mode, line spacing and etc.
TEtvRecordCloner Records cloning for the one dataset or for the group of datasets linked as master-detail or differently. Cloning confirmation and confirmation on each detail-dataset, events for finishing fill for each record.
TEtvDBRichEdit. Transparent (record-by-record) search and replacing, i.e. it can process from record to record, dialog for it. Search and replacing again. Popup menu with font, basic font, paragraph, search/replacing, print, copying, inserting, selecting all.
Various functions for design and run time, property and component editors.

Last updated Feb-24-2003