xtd.forms - Reference Guide  0.1.0
Modern c++17 library containing classes for creating Windows-based applications that take full advantage of the rich user interface features available in the Microsoft Windows, Apple macOS and Linux like Ubuntu operating system.
xtd::forms::combo_box Class Reference

Represents a Windows combo box control. More...

#include <combo_box.hpp>

Inheritance diagram for xtd::forms::combo_box:
xtd::forms::list_control xtd::forms::control xtd::forms::component xtd::forms::iwin32_window

Public Member Functions

 combo_box ()
 Initializes a new instance of the combo_box class. More...
 
void begin_update ()
 
virtual drawing::size default_size () const override
 
combo_box_style drop_down_style () const
 
combo_boxdrop_down_style (combo_box_style drop_down_style)
 
void end_update ()
 
item_collectionitems ()
 
const item_collectionitems () const
 
const combo_boxitems (const item_collection &items)
 
list_controlselected_index (size_t selected_index) override
 When overridden in a derived class, Sets the zero-based index of the currently selected item. More...
 
const item & selected_item () const
 
combo_boxselected_item (const item &selected_item)
 
virtual bool sorted () const
 
virtual combo_boxsorted (bool sorted)
 
controltext (const ustring &text) override
 
- Public Member Functions inherited from xtd::forms::list_control
virtual size_t selected_index () const
 Gets the zero-based index of the currently selected item. More...
 
virtual ustring value_member () const
 
virtual list_controlvalue_member (const ustring &value_member)
 
- Public Member Functions inherited from xtd::forms::control
 control ()
 Initializes a new instance of the Control class with default settings. More...
 
 control (const ustring &text)
 Initializes a new instance of the control class with specific text. More...
 
 control (const control &parent, const ustring &text)
 nitializes a new instance of the control class as a child control, with specific text. More...
 
 control (const ustring &text, int32_t left, int32_t top, int32_t width, int32_t height)
 Initializes a new instance of the control class with specific text, size, and location. More...
 
 control (const control &parent, const ustring &text, int32_t left, int32_t top, int32_t width, int32_t height)
 Initializes a new instance of the control class as a child control, with specific text, size, and location. More...
 
virtual anchor_styles anchor () const
 Gets the edges of the container to which a control is bound and determines how a control is resized with its parent. More...
 
virtual controlanchor (anchor_styles anchor)
 Gets the edges of the container to which a control is bound and determines how a control is resized with its parent. More...
 
virtual drawing::point auto_scroll_point () const
 Gets where this control is scrolled to in scroll_control_into_view(control). More...
 
virtual bool auto_size () const
 Gets a value that indicates whether the control resizes based on its contents. More...
 
virtual controlauto_size (bool auto_size)
 Sets a value that indicates whether the control resizes based on its contents. More...
 
virtual drawing::color back_color () const
 Gets the background color for the control. More...
 
virtual controlback_color (const drawing::color &color)
 Sets the background color for the control. More...
 
virtual int32_t bottom () const
 Gets the distance, in pixels, between the bottom edge of the control and the top edge of its container's client area. More...
 
virtual drawing::rectangle bounds () const
 Gets the size and location of the control including its nonclient elements, in pixels, relative to the parent control. More...
 
virtual controlbounds (const drawing::rectangle &bounds)
 Sets the size and location of the control including its nonclient elements, in pixels, relative to the parent control. More...
 
virtual bool can_focus () const
 Gets a value indicating whether the control can receive focus. More...
 
bool can_raise_events () const override
 Determines if events can be raised on the control. More...
 
virtual bool can_select () const
 Gets a value indicating whether the control can be selected. More...
 
virtual const drawing::rectangleclient_rectangle () const
 Gets the rectangle that represents the client area of the control. More...
 
virtual const drawing::sizeclient_size () const
 Gets the height and width of the client area of the control. More...
 
virtual controlclient_size (const drawing::size &client_size)
 Sets the height and width of the client area of the control. More...
 
virtual ustring compagny_name () const
 Gets the name of the company or creator of the application containing the control. More...
 
virtual control_collectioncontrols ()
 Gets the collection of controls contained within the control. More...
 
virtual const control_collectioncontrols () const
 Gets the collection of controls contained within the control. More...
 
void create_control ()
 
drawing::graphics create_graphics () const
 
virtual void create_handle ()
 
virtual bool created ()
 Gets a value indicating whether the control has been created. More...
 
virtual forms::cursor cursor () const
 
virtual controlcursor (const forms::cursor &cursor)
 
virtual forms::cursor default_cursor () const
 
virtual drawing::font default_font () const
 
void destroy_control ()
 
virtual void destroy_handle ()
 
virtual drawing::rectangle display_rectangle () const
 
virtual dock_style dock () const
 Gets or sets which control borders are docked to its parent control and determines how a control is resized with its parent. More...
 
virtual controldock (dock_style dock)
 
virtual bool enabled () const
 
virtual controlenabled (bool enabled)
 
bool focus ()
 
virtual bool focused () const
 
virtual drawing::font font () const
 
virtual controlfont (const drawing::font &font)
 
virtual drawing::color fore_color () const
 
virtual controlfore_color (const drawing::color &color)
 
intptr_t handle () const override
 Gets the handle to the window represented by the implementer. More...
 
virtual int32_t height () const
 
virtual controlheight (int32_t height)
 
virtual void hide ()
 
virtual void invalidate () const
 
virtual void invalidate (bool invalidate_children) const
 
virtual void invalidate (const drawing::rectangle &rect) const
 
virtual void invalidate (const drawing::rectangle &rect, bool invalidate_children) const
 
void invoke (delegate< void(std::vector< std::any >)> value, const std::vector< std::any > &args)
 
void invoke (delegate< void()> value)
 
bool is_handle_created () const
 
virtual int32_t left () const
 
virtual controlleft (int32_t left)
 
virtual drawing::point location () const
 
virtual controllocation (const drawing::point &location)
 
virtual const ustringname () const
 
virtual controlname (const ustring &name)
 
virtual std::optional< control_refparent () const
 
virtual controlparent (const control &parent)
 
virtual controlparent (std::nullptr_t)
 
void perform_layout ()
 Forces the control to apply layout logic to all its child controls. More...
 
xtd::drawing::point point_to_client (const xtd::drawing::point &p)
 
xtd::drawing::point point_to_screen (const xtd::drawing::point &p)
 
virtual ustring product_name () const
 
bool recreating_handle () const
 
virtual void refresh () const
 
void resume_layout ()
 Resumes usual layout logic. More...
 
void resume_layout (bool perform_layout)
 Resumes usual layout logic, optionally forcing an immediate layout of pending layout requests. More...
 
virtual int32_t right () const
 
intptr_t send_message (intptr_t hwnd, int32_t msg, intptr_t wparam, intptr_t lparam) const
 
void set_auto_size_mode (auto_size_mode auto_size_mode)
 
void set_bounds (int32_t x, int32_t y, int32_t width, int32_t height)
 
void set_bounds (int32_t x, int32_t y, int32_t width, int32_t height, bounds_specified specified)
 
virtual void show ()
 
virtual drawing::size size () const
 
virtual controlsize (const drawing::size &size)
 
void suspend_layout ()
 Temporarily suspends the layout logic for the control. More...
 
virtual std::any tag () const
 Gets the object that contains data about the control. More...
 
virtual controltag (std::any tag)
 Sets the object that contains data about the control. More...
 
virtual const ustringtext () const
 
virtual ustring to_string () const
 
virtual int32_t top () const
 
virtual controltop (int32_t top)
 
virtual std::optional< control_reftop_level_control () const
 
virtual void update () const
 
virtual bool visible () const
 
virtual controlvisible (bool visible)
 
virtual int32_t width () const
 
virtual controlwidth (int32_t width)
 

Public Attributes

event< combo_box, event_handler< control & > > drop_down_style_changed
 
- Public Attributes inherited from xtd::forms::list_control
event< list_control, event_handler< control & > > selected_index_changed
 
event< list_control, event_handler< control & > > selected_value_changed
 
event< list_control, event_handler< control & > > value_member_changed
 
- Public Attributes inherited from xtd::forms::control
event< control, event_handler< control & > > auto_size_changed
 
event< control, event_handler< control & > > back_color_changed
 
event< control, event_handler< control & > > click
 
event< control, event_handler< control & > > client_size_changed
 
event< control, control_event_handler< control & > > control_added
 
event< control, control_event_handler< control & > > control_removed
 
event< control, event_handler< control & > > cursor_changed
 
event< control, event_handler< control & > > dock_changed
 
event< control, event_handler< control & > > double_click
 
event< control, event_handler< control & > > enabled_changed
 
event< control, event_handler< control & > > font_changed
 
event< control, event_handler< control & > > fore_color_changed
 
event< control, event_handler< control & > > got_focus
 
event< control, event_handler< control & > > handle_created
 
event< control, event_handler< control & > > handle_destroyed
 
event< control, key_event_handler< control & > > key_down
 
event< control, key_press_event_handler< control & > > key_press
 
event< control, key_event_handler< control & > > key_up
 
event< control, event_handler< control & > > layout
 Occurs when a control should reposition its child controls. More...
 
event< control, event_handler< control & > > location_changed
 
event< control, event_handler< control & > > lost_focus
 
event< control, mouse_event_handler< control & > > mouse_click
 
event< control, mouse_event_handler< control & > > mouse_double_click
 
event< control, mouse_event_handler< control & > > mouse_down
 
event< control, event_handler< control & > > mouse_enter
 
event< control, mouse_event_handler< control & > > mouse_horizontal_wheel
 
event< control, event_handler< control & > > mouse_leave
 
event< control, mouse_event_handler< control & > > mouse_move
 
event< control, mouse_event_handler< control & > > mouse_up
 
event< control, mouse_event_handler< control & > > mouse_wheel
 
event< control, paint_event_handler< control & > > paint
 
event< control, event_handler< control & > > parent_changed
 
event< control, event_handler< control & > > resize
 
event< control, event_handler< control & > > size_changed
 
event< control, event_handler< control & > > text_changed
 
event< control, event_handler< control & > > visible_changed
 

Protected Member Functions

forms::create_params create_params () const override
 
virtual void on_drop_down_style_changed (const event_args &e)
 
void on_handle_created (const event_args &e) override
 
void on_selected_value_changed (const event_args &e) override
 
void set_bounds_core (int32_t x, int32_t y, int32_t width, int32_t height, bounds_specified specified) override
 Performs the work of setting the specified bounds of this control. More...
 
void set_client_size_core (int32_t width, int32_t height) override
 Sets the size of the client area of the control. More...
 
virtual void wm_mouse_double_click (message &message)
 
virtual void wm_mouse_down (message &message)
 
virtual void wm_mouse_up (message &message)
 
virtual void wm_reflect_command (message &message)
 
void wnd_proc (message &message) override
 Processes Windows messages. More...
 
- Protected Member Functions inherited from xtd::forms::list_control
virtual bool allow_selection ()
 Gets a value indicating whether the list enables selection of list items. More...
 
virtual drawing::color default_back_color () const override
 Gets the default background color of the control. More...
 
virtual drawing::color default_fore_color () const override
 
virtual void on_selected_index_changed (const event_args &e)
 
virtual void on_value_member_changed (const event_args &e)
 
- Protected Member Functions inherited from xtd::forms::control
virtual void def_wnd_proc (message &message)
 
bool get_style (control_styles flag) const
 Retrieves the value of the specified control style bit for the control. More...
 
virtual drawing::size measure_control () const
 Measure this control. More...
 
drawing::size measure_text () const
 
virtual void on_auto_size_changed (const event_args &e)
 
virtual void on_back_color_changed (const event_args &e)
 
virtual void on_click (const event_args &e)
 
virtual void on_client_size_changed (const event_args &e)
 
virtual void on_control_added (const control_event_args &e)
 
virtual void on_control_removed (const control_event_args &e)
 
virtual void on_create_control ()
 
virtual void on_cursor_changed (const event_args &e)
 
virtual void on_dock_changed (const event_args &e)
 
virtual void on_double_click (const event_args &e)
 
virtual void on_enabled_changed (const event_args &e)
 
virtual void on_font_changed (const event_args &e)
 
virtual void on_fore_color_changed (const event_args &e)
 
virtual void on_got_focus (const event_args &e)
 
virtual void on_handle_destroyed (const event_args &e)
 
virtual void on_key_down (key_event_args &e)
 
virtual void on_key_press (key_press_event_args &e)
 
virtual void on_key_up (key_event_args &e)
 
virtual void on_layout (const event_args &e)
 
virtual void on_location_changed (const event_args &e)
 
virtual void on_lost_focus (const event_args &e)
 
virtual void on_mouse_click (const mouse_event_args &e)
 
virtual void on_mouse_double_click (const mouse_event_args &e)
 
virtual void on_mouse_down (const mouse_event_args &e)
 
virtual void on_mouse_enter (const event_args &e)
 
virtual void on_mouse_horizontal_wheel (const mouse_event_args &e)
 
virtual void on_mouse_leave (const event_args &e)
 
virtual void on_mouse_move (const mouse_event_args &e)
 
virtual void on_mouse_up (const mouse_event_args &e)
 
virtual void on_mouse_wheel (const mouse_event_args &e)
 
virtual void on_paint (paint_event_args &e)
 
virtual void on_parent_back_color_changed (const event_args &e)
 
virtual void on_parent_changed (const event_args &e)
 
virtual void on_parent_cursor_changed (const event_args &e)
 
virtual void on_parent_font_changed (const event_args &e)
 
virtual void on_parent_fore_color_changed (const event_args &e)
 
virtual void on_resize (const event_args &e)
 
virtual void on_size_changed (const event_args &e)
 
virtual void on_text_changed (const event_args &e)
 
virtual void on_visible_changed (const event_args &e)
 
virtual void recreate_handle ()
 
void set_style (control_styles flag, bool value)
 Sets a specified control_styles flag to either true or false. More...
 
- Protected Member Functions inherited from xtd::forms::component
bool design_mode () const
 Gets a value that indicates whether the component is currently in design mode. More...
 

Protected Attributes

int32_t drop_down_height_ = 0
 
combo_box_style drop_down_style_ = combo_box_style::drop_down
 
int32_t drop_down_width_ = 0
 
item_collection items_
 
item selected_item_
 
bool sorted_ = false
 
bool user_set_size_ = false
 

Additional Inherited Members

- Public Types inherited from xtd::forms::list_control
using item_collection = layout::arranged_element_collection< item, item::sorter >
 
- Public Types inherited from xtd::forms::control
using control_collection = layout::arranged_element_collection< control_ref >
 Represents a collection of controls. More...
 
- Static Public Member Functions inherited from xtd::forms::control
template<typename control_t >
static std::unique_ptr< control_t > create (const drawing::point &location={-1, -1}, const drawing::size &size={-1, -1}, const drawing::color &back_color=drawing::color::empty, const drawing::color &fore_color=drawing::color::empty)
 
template<typename control_t >
static std::unique_ptr< control_t > create (const control &parent, const drawing::point &location={-1, -1}, const drawing::size &size={-1, -1}, const drawing::color &back_color=drawing::color::empty, const drawing::color &fore_color=drawing::color::empty)
 
template<typename control_t >
static std::unique_ptr< control_t > create (const ustring &text, const drawing::point &location={-1, -1}, const drawing::size &size={-1, -1}, const drawing::color &back_color=drawing::color::empty, const drawing::color &fore_color=drawing::color::empty)
 
template<typename control_t >
static std::unique_ptr< control_t > create (const control &parent, const ustring &text, const drawing::point &location={-1, -1}, const drawing::size &size={-1, -1}, const drawing::color &back_color=drawing::color::empty, const drawing::color &fore_color=drawing::color::empty)
 
static std::optional< control_reffrom_child_handle (intptr_t handle)
 
static std::optional< control_reffrom_handle (intptr_t handle)
 
static forms::mouse_buttons mouse_buttons ()
 

Detailed Description

Represents a Windows combo box control.

Remarks
A combo_box displays a text box combined with a list_box, which enables the user to select items from the list or enter a new value.
The drop_down_style property specifies whether the list is always displayed or whether the list is displayed in a drop-down. The drop_down_style property also specifies whether the text portion can be edited. See combo_box_style for the available settings and their effects. There is no setting to always display the list and disallow entering a new value. To display a list to which no new values can be added, use a list_box control.
To add or remove objects in the list at run time, use methods of the combo_box.object_collection class (through the items property of the combo_box). You can assign an array of object with the push_range method. The list then displays the default string value for each object. You can add individual objects with thepush method. You can delete items with the erase method or clear the entire list with the clear method.
In addition to display and selection functionality, the combo_box also provides features that enable you to efficiently add items to the combo_box and to find text within the items of the list. With the begin_update and end_update methods, you can add a large number of items to the combo_box without the control being repainted each time an item is added to the list. The find_string and find_string_exact methods enable you to search for an item in the list that contains a specific search string.
You can use these properties to manage the currently selected item in the list, the text property to specify the string displayed in the editing field, the selected_index property to get or set the current item, and the selected_item property to get or set a reference to the object.

Constructor & Destructor Documentation

§ combo_box()

xtd::forms::combo_box::combo_box ( )

Initializes a new instance of the combo_box class.

Member Function Documentation

§ create_params()

forms::create_params xtd::forms::combo_box::create_params ( ) const
overrideprotectedvirtual
Remarks
Gets the required creation parameters when the control handle is created.
Returns
A create_params that contains the required creation parameters when the handle to the control is created.

Reimplemented from xtd::forms::control.

§ selected_index()

list_control& xtd::forms::combo_box::selected_index ( size_t  selected_index)
overridevirtual

When overridden in a derived class, Sets the zero-based index of the currently selected item.

Parameters
selected_indexA zero-based index of the currently selected item. A value of negative one (-1) is returned if no item is selected.

Implements xtd::forms::list_control.

§ set_bounds_core()

void xtd::forms::combo_box::set_bounds_core ( int32_t  x,
int32_t  y,
int32_t  width,
int32_t  height,
bounds_specified  specified 
)
overrideprotectedvirtual

Performs the work of setting the specified bounds of this control.

Parameters
xThe new left property value of the control.
yThe new top property value of the control.
widthThe new width property value of the control.
heightThe new height property value of the control.
specifiedA bitwise combination of the bounds_specified values.
Remarks
Typically, the parameters that correspond to the bounds not included in the specified parameter are passed in with their current values. For example, the height, width, or the y or y properties of the location property can be passed in with a reference to the current instance of the control. However all values passed in are honored and applied to the control.
The specified parameter represents the elements of the controls Bounds changed by your application. For example, if you change the size of the control, the specified parameter value is the size value of bounds_specified. However, if the size is adjusted in response to the dock property being set, the pecified parameter value is the none value of bounds_specified.
Notes to Inheritors
When overriding set_bounds_core(int32_t, int32_t, int32_t, int32_t, bounds_specified) in a derived class, be sure to call the base class's set_bounds_core(int32_t, int32_t, int32_t, int32_t, bounds_specified) method to force the bounds of the control to change. Derived classes can add size restrictions to the set_bounds_core(int32_t, int32_t, int32_t, int32_t, bounds_specified) method.

Reimplemented from xtd::forms::control.

§ set_client_size_core()

void xtd::forms::combo_box::set_client_size_core ( int32_t  width,
int32_t  height 
)
overrideprotectedvirtual

Sets the size of the client area of the control.

Parameters
widthThe client area width, in pixels.
heightThe client area height, in pixels.
Remarks
The client area starts at the (0, 0) location and extends to the (width, height) location.
Typically, you should not set the client_size of the control.
Notes to Inheritors
When overriding set_client_size_core(int32_t, int32_t) in a derived class, be sure to call the base class's set_client_size_core(int32_t, int32_t) method so that the client_size property is adjusted.

Reimplemented from xtd::forms::control.

§ wnd_proc()

void xtd::forms::combo_box::wnd_proc ( message m)
overrideprotectedvirtual

Processes Windows messages.

Parameters
mThe Windows Message to process.
Remarks
All messages are sent to the wnd°proc method after getting filtered through the pre_process_message method.
Notes to Inheritors
Inheriting controls should call the base class's wnd_proc(message&) method to process any messages that they do not handle.

Reimplemented from xtd::forms::control.


The documentation for this class was generated from the following file: