WinForms › Combo Box

Combo Box

.NET Framework 4.8.NET 6 / 8 / 10v9.0.0WinForms

The shared base of BinaryTextComboBox and BinaryImageComboBox: a Windows Forms combo box that draws its own flat border, drop-down button and items, in colours you choose.

26public types

307public members

1namespaces

Assembly

Assembly	`Binarymission.WinForms.Controls.BinaryComboBox.dll`
Root namespace	`Binarymission.WinForms.Controls.ListControls`
Target frameworks	.NET Framework 4.8, .NET 6 / 8 / 10

Overview

What it is for

Everything the two Hypernova combo boxes have in common lives here: the colours of the border, the drop-down button and the highlighted item, how the border behaves when the pointer and the focus come and go, the optional push-button style drop-down button, the look of the single-column drop-down list, and the extended read-only mode. The class is abstract and is not in the Toolbox; place a BinaryTextComboBox (text, data binding, auto-completion, a multi-column drop-down) or a BinaryImageComboBox (an image beside each item, drive and font lists) on the form instead.

Colours

Two colours drive the whole look. CustomControlBorderColor is the border and the outline round the drop-down button. CustomPaintingColor is blended with the window colour to give the drop-down button face and the highlighted item, and blended again for the button while the list is open. The three alpha-blending factors (0 to 255) say how much of it goes into each blend: AlphaBlendFactorForItemSelectionColor, AlphaBlendFactorForDropDownPressedColor and AlphaBlendFactorForControlPainting. EmulateThisXPTheme sets all five at once to one of the Windows XP colour schemes.

The border

With ShowBorderAlways on (the default) the border is always drawn; CustomControlBorderColorWhenNotInFocus gives it a quieter colour while the control does not have the focus. With it off, the border appears only while the pointer is over the control or it has the focus.

Things to know

Simple is not supported: DropDownStyle ignores it.
Right-to-left layout is not supported: RightToLeft stays No.
The flat drawing is used by BinaryImageComboBox always, and by BinaryTextComboBox while its BinaryTextComboBox.DisplayStyleIsFlat is true; otherwise the text combo box looks like a standard Windows combo box and the colours here are not used.
Metrics are logical pixels (1/96 inch), scaled to the display the control is on.

Getting started

A text combo box in the application's accent colour, with a quiet grey border while it does not have the focus.

var statusPicker = new BinaryTextComboBox
{
    Location = new Point(12, 12),
    Width = 220,
    DropDownStyle = ComboBoxStyle.DropDownList,
};
statusPicker.Items.AddRange(new object[] { "Open", "In progress", "On hold", "Closed" });
statusPicker.SelectedIndex = 0;

statusPicker.CustomPaintingColor = Color.FromArgb(0, 120, 215);
statusPicker.CustomControlBorderColor = Color.FromArgb(0, 90, 158);
statusPicker.CustomControlBorderColorWhenNotInFocus = Color.Silver;
statusPicker.AlphaBlendFactorForItemSelectionColor = 90;   // a light tint for the highlighted item
statusPicker.ControlArrowColor = Color.FromArgb(0, 90, 158);

statusPicker.SelectedIndexChanged += (sender, e) => Text = "Status: " + statusPicker.SelectedItem;
Controls.Add(statusPicker);

API reference

`Binarymission.WinForms.Controls.ListControls`

class `BinaryComboBox`	The shared base of `BinaryTextComboBox` and `BinaryImageComboBox`: a Windows Forms combo box that draws its own flat border, drop-down button and items, in colours you choose.
class `BinaryComboBoxColumn`	A `DataGridView` column whose cells are edited with a `BinaryTextComboBox` - so a grid cell can offer the multi-column drop-down, its sorting, grouping and filtering, and the Hypernova look.
class `BinaryImageComboBox`	A pick-list combo box that shows an image beside each item - and can turn itself into a ready-made drive list or font list.
class `DriveInformation`	Details of one entry of a `BinaryImageComboBox` drive list: its path, volume label, display name and type, and the file-system limits Windows reports for it.
delegate `DriveSelectionChangeHandler`	Represents the method that handles `DriveSelectionChanged`.
delegate `DropDownProcessHandler`	Represents the method that handles `DropDownAboutToBeShown`, and can stop the list opening.
class `BinaryTextComboBox`	A text combo box that adds auto-completion, a read-only mode, and a multi-column drop-down that can sort, filter, group and export the rows of a data source - the Hypernova combo box for picking a record by its name.
delegate `AutoCompletingHandler`	Represents the method that handles `AutoCompleting`.
delegate `CustomSortingHandler`	Represents the method that handles `CustomSorting`.
delegate `DropDownProcessHandler`	Represents the method that handles `DropDownAboutToBeShown`, and can stop the drop-down opening.
class `MultiColumnDropDownWindowConfiguration`	The appearance of the multi-column drop-down of a `BinaryTextComboBox`: its header and footer bands, its column headings and the message it shows when there are no rows.
delegate `NotInListHandler`	Represents the method that handles `NotInList`.
class `BinaryTreeListViewComboBoxCell`	The cell of a `BinaryComboBoxColumn`: a combo box cell whose editor is a `BinaryTextComboBox`.
enum `BuiltinFilterOnNonStringTypeColumnFilterResultsMode`	How the built-in filter of the `BinaryTextComboBox` multi-column drop-down matches a column that holds numbers, dates or other values that are not text.
enum `ColumnDataTypeFormat`	The kind of value a column of the `BinaryTextComboBox` multi-column drop-down holds, which decides how its values are formatted for display.
class `ColumnDataTypeFormatInfoContainer`	How one column of the `BinaryTextComboBox` multi-column drop-down formats its values: the kind of value it holds and the format string to apply.
enum `DropDownWindowDisplayOrientation`	Which way the multi-column drop-down of a `BinaryTextComboBox` extends from the control.
enum `FontNameDisplayStyle`	How a `BinaryImageComboBox` font list draws the font names.
enum `HeaderImageStyle`	Which picture, if any, the header band of a multi-column drop-down shows.
enum `ItemSelectionClick`	Whether the user picks a row of the `BinaryTextComboBox` multi-column drop-down with one click or two.
enum `ListStyle`	What a `BinaryImageComboBox` lists: your own images and text, the computer's drives, or the installed fonts.
class `MultiColumnDropDownWindowConfiguration`	The appearance of the multi-column drop-down opened by the cells of a `BinaryComboBoxColumn`: its header and footer bands, its column heading font and its no-data message.
class `MultiColumnDropDownWindowConfigurationTypeConverter`	Lets the Properties window show a `MultiColumnDropDownWindowConfiguration` as an expandable set of its own properties, rather than as a single value.
enum `MultiColumnDroplistWindowAnimationStyle`	How the multi-column drop-down of a `BinaryTextComboBox` animates as it closes after the user picks a row.
class `MultiColumnViewUIElementsTextProvider`	The captions, menu commands and messages of the `BinaryTextComboBox` multi-column drop-down, gathered in one place so they can be translated or reworded.
enum `XPTheme`	The Windows XP colour schemes a Hypernova combo box can take its colours from.