I recently studied UniGUI's TuniDBGrid and recorded it so as not to forget it.
Important properties of TuniDBGrid include:
1. Columns - TUniDBGridColumns and TUniDBGridColumn
Important properties of each column object (TUniDBGridColumn) include:
- CheckBoxField : TUniCheckBoxField
Columns as relevant properties for CheckBox actions
| Attributes |
Types of |
illustrate |
| AutoPost |
Boolean |
When the user clicks the CheckBox, change the front-end display and decide according to this property: True - automatically commit to the dataset immediately and refresh the front-end display False—Only change the front-end display, and submit the dataset when the record scrolls |
| BooleanFieldOnly |
Boolean |
Is it only for Boolean fields, True - only Boolean fields can be recognized, non-Boolean fields will not be able to display CheckBox False—DisplayValues and FieldValues can be handled for non-Boolean fields |
| Enabled |
Boolean |
Whether to allow the CheckBox to be displayed |
| DisplayValues/ FieldValues |
string |
The joint determines the corresponding values of the CheckBox in different states. FieldValues stores the field value, and DisplayValues stores the displayed text. If it is blank, it means that the text is not displayed, only the CheckBox is displayed. Each value is distinguished by a semicolon (;), and the text is displayed on the right side of the CheckBox. . As shown below:
|
- DisplayMemo:Boolean
For TMemoField, whether to display the word (Memo), the default is False
False—Do not display the field content, display the word (Memo)
True—do not display the word (Memo), but directly display the field content
- Filtering : TUniColumnFilter
The filter edit box is displayed under the column header, and the column data is automatically filtered, as shown in the following figure:
Refer to the GridFilter example under Demos. To implement this feature, you must:
A. Put a TUniHiddenPanel control on the form, and then place TUniEdit, TUniComboBox, TUniDBLookupComboBox and other controls on this hidden Panel, as shown below:
B. Set the Filtering of each column, and set its Editor property to the corresponding edit control
C. Set relevant properties for the edit control, such as TUniDBLookupComboBox needs to set ListSource, etc.
| Attributes |
Types of |
illustrate |
| ChangeDelay |
Integer |
The number of milliseconds to delay filtering after the user types a character |
| Editor |
TControl |
Filtered input box, filter according to the content of the input box. TUniDBLookupComboBox is filtered by the value of KeyField |
| Enabled |
Boolean |
whether to allow filtering |
- GroupHeader 和 GroupHeaderSeparator
Display headers in multiple columns, for example, the style when GroupHeader = a;b;c is shown in the following figure:
- ShowSummary：Boolean
Whether to display the total value, used in conjunction with the Grid's Summary property.
- Sortable：Boolean
Whether to allow sorting operations. When the sorting operation is enabled, the sorting symbol is displayed next to the field name, and the sorting menu in the Menu is available, as shown in the following figure:
- Editor ： TControl;
When editing the field, what kind of control the corresponding unit uses to process, this function is very powerful. For example, setting TuniComboBox as Editor will completely replace the function of field Picklist, as shown in the following figure:
- Memu (TUniColumnMenu)
Controls the menu displayed by the column header drop-down
| Attributes |
Types of |
illustrate |
| ColoumnHideable |
Boolean |
Whether to allow hidden fields, the default is True, which allows the user to hide the specified column by checking, as shown below:
|
| MenuEnabled |
Boolean |
Whether to allow menus to be displayed for columns |
| MenuText |
String |
The text displayed on the menu in this column is empty by default, which means the field DisplayLabel is displayed, otherwise the text is displayed. As shown below:
|
- ImageOptions
When the field needs to display an image, use the ImageOptions property in conjunction with the OnFieldImage event, where:
| Attributes |
Types of |
illustrate |
| Height/Width |
Integer |
Display image size |
| Visible |
Boolean |
Whether to display the image, True triggers the OnFieldImage event for image processing, such as: procedure TMainForm.UniDBGrid1FieldImage(const Column: TUniDBGridColumn; const AField: TField; var OutImage: TGraphic; var DoNotDispose: Boolean; var ATransparent: TUniTransparentOption); begin if SameText(AField.FieldName, 'gender') then begin // code to process the image DoNotDispose := True; // return image based on field value if AField.AsString = 'male' then OutImage := UniImage1.Picture.Graphic else if AField.AsString = 'female' then OutImage := UniImage2.Picture.Graphic; end; end; |
This method allows the column to display an image button, such as:
