/*
* This file is part of OpenTTD.
* OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
* OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see .
*/
/** @file dropdown.cpp Implementation of the dropdown widget. */
#include "../stdafx.h"
#include "../window_gui.h"
#include "../string_func.h"
#include "../strings_func.h"
#include "../window_func.h"
#include "../zoom_func.h"
#include "../timer/timer.h"
#include "../timer/timer_window.h"
#include "dropdown_type.h"
#include "dropdown_widget.h"
#include "../safeguards.h"
static const NWidgetPart _nested_dropdown_menu_widgets[] = {
NWidget(NWID_HORIZONTAL),
NWidget(WWT_PANEL, COLOUR_END, WID_DM_ITEMS), SetScrollbar(WID_DM_SCROLL), EndContainer(),
NWidget(NWID_SELECTION, INVALID_COLOUR, WID_DM_SHOW_SCROLL),
NWidget(NWID_VSCROLLBAR, COLOUR_END, WID_DM_SCROLL),
EndContainer(),
EndContainer(),
};
static WindowDesc _dropdown_desc(__FILE__, __LINE__,
WDP_MANUAL, nullptr, 0, 0,
WC_DROPDOWN_MENU, WC_NONE,
WDF_NO_FOCUS,
std::begin(_nested_dropdown_menu_widgets), std::end(_nested_dropdown_menu_widgets)
);
/** Drop-down menu window */
struct DropdownWindow : Window {
WidgetID parent_button; ///< Parent widget number where the window is dropped from.
Rect wi_rect; ///< Rect of the button that opened the dropdown.
const DropDownList list; ///< List with dropdown menu items.
int selected_result; ///< Result value of the selected item in the list.
byte click_delay = 0; ///< Timer to delay selection.
bool drag_mode = true;
bool instant_close; ///< Close the window when the mouse button is raised.
int scrolling = 0; ///< If non-zero, auto-scroll the item list (one time).
Point position; ///< Position of the topleft corner of the window.
Scrollbar *vscroll;
Dimension items_dim; ///< Calculated cropped and padded dimension for the items widget.
/**
* Create a dropdown menu.
* @param parent Parent window.
* @param list Dropdown item list.
* @param selected Initial selected result of the list.
* @param button Widget of the parent window doing the dropdown.
* @param wi_rect Rect of the button that opened the dropdown.
* @param instant_close Close the window when the mouse button is raised.
* @param wi_colour Colour of the parent widget.
*/
DropdownWindow(Window *parent, DropDownList &&list, int selected, WidgetID button, const Rect wi_rect, bool instant_close, Colours wi_colour)
: Window(&_dropdown_desc)
, parent_button(button)
, wi_rect(wi_rect)
, list(std::move(list))
, selected_result(selected)
, instant_close(instant_close)
{
assert(!this->list.empty());
this->parent = parent;
this->CreateNestedTree();
this->GetWidget(WID_DM_ITEMS)->colour = wi_colour;
this->GetWidget(WID_DM_SCROLL)->colour = wi_colour;
this->vscroll = this->GetScrollbar(WID_DM_SCROLL);
this->UpdateSizeAndPosition();
this->FinishInitNested(0);
CLRBITS(this->flags, WF_WHITE_BORDER);
}
void Close([[maybe_unused]] int data = 0) override
{
/* Finish closing the dropdown, so it doesn't affect new window placement.
* Also mark it dirty in case the callback deals with the screen. (e.g. screenshots). */
this->Window::Close();
Point pt = _cursor.pos;
pt.x -= this->parent->left;
pt.y -= this->parent->top;
this->parent->OnDropdownClose(pt, this->parent_button, this->selected_result, this->instant_close);
/* Set flag on parent widget to indicate that we have just closed. */
NWidgetCore *nwc = this->parent->GetWidget(this->parent_button);
if (nwc != nullptr) SetBit(nwc->disp_flags, NDB_DROPDOWN_CLOSED);
}
void OnFocusLost(bool closing) override
{
if (!closing) {
this->instant_close = false;
this->Close();
}
}
/**
* Fit dropdown list into available height, rounding to average item size. Width is adjusted if scrollbar is present.
* @param[in,out] desired Desired dimensions of dropdown list.
* @param list Dimensions of the list itself, without padding or cropping.
* @param available_height Available height to fit list within.
*/
void FitAvailableHeight(Dimension &desired, const Dimension &list, uint available_height)
{
if (desired.height < available_height) return;
/* If the dropdown doesn't fully fit, we a need a dropdown. */
uint avg_height = list.height / (uint)this->list.size();
uint rows = std::max((available_height - WidgetDimensions::scaled.dropdownlist.Vertical()) / avg_height, 1U);
desired.width = std::max(list.width, desired.width - NWidgetScrollbar::GetVerticalDimension().width);
desired.height = rows * avg_height + WidgetDimensions::scaled.dropdownlist.Vertical();
}
/**
* Update size and position of window to fit dropdown list into available space.
*/
void UpdateSizeAndPosition()
{
Rect button_rect = this->wi_rect.Translate(this->parent->left, this->parent->top);
/* Get the dimensions required for the list. */
Dimension list_dim = GetDropDownListDimension(this->list);
/* Set up dimensions for the items widget. */
Dimension widget_dim = list_dim;
widget_dim.width += WidgetDimensions::scaled.dropdownlist.Horizontal();
widget_dim.height += WidgetDimensions::scaled.dropdownlist.Vertical();
/* Width should match at least the width of the parent widget. */
widget_dim.width = std::max(widget_dim.width, button_rect.Width());
/* Available height below (or above, if the dropdown is placed above the widget). */
uint available_height_below = std::max(GetMainViewBottom() - button_rect.bottom - 1, 0);
uint available_height_above = std::max(button_rect.top - 1 - GetMainViewTop(), 0);
/* Is it better to place the dropdown above the widget? */
if (widget_dim.height > available_height_below && available_height_above > available_height_below) {
FitAvailableHeight(widget_dim, list_dim, available_height_above);
this->position.y = button_rect.top - widget_dim.height;
} else {
FitAvailableHeight(widget_dim, list_dim, available_height_below);
this->position.y = button_rect.bottom + 1;
}
this->position.x = (_current_text_dir == TD_RTL) ? button_rect.right + 1 - (int)widget_dim.width : button_rect.left;
this->items_dim = widget_dim;
this->GetWidget(WID_DM_SHOW_SCROLL)->SetDisplayedPlane(list_dim.height > widget_dim.height ? 0 : SZSP_NONE);
/* Capacity is the average number of items visible */
this->vscroll->SetCapacity((widget_dim.height - WidgetDimensions::scaled.dropdownlist.Vertical()) * this->list.size() / list_dim.height);
this->vscroll->SetCount(this->list.size());
/* If the dropdown is positioned above the parent widget, start selection at the bottom. */
if (this->position.y < button_rect.top && list_dim.height > widget_dim.height) this->vscroll->UpdatePosition(INT_MAX);
}
void UpdateWidgetSize(WidgetID widget, Dimension *size, [[maybe_unused]] const Dimension &padding, [[maybe_unused]] Dimension *fill, [[maybe_unused]] Dimension *resize) override
{
if (widget == WID_DM_ITEMS) *size = this->items_dim;
}
Point OnInitialPosition([[maybe_unused]] int16_t sm_width, [[maybe_unused]] int16_t sm_height, [[maybe_unused]] int window_number) override
{
return this->position;
}
/**
* Find the dropdown item under the cursor.
* @param[out] value Selected item, if function returns \c true.
* @return Cursor points to a dropdown item.
*/
bool GetDropDownItem(int &value)
{
if (GetWidgetFromPos(this, _cursor.pos.x - this->left, _cursor.pos.y - this->top) < 0) return false;
const Rect &r = this->GetWidget(WID_DM_ITEMS)->GetCurrentRect().Shrink(WidgetDimensions::scaled.dropdownlist);
int y = _cursor.pos.y - this->top - r.top;
int pos = this->vscroll->GetPosition();
for (const auto &item : this->list) {
/* Skip items that are scrolled up */
if (--pos >= 0) continue;
int item_height = item->Height();
if (y < item_height) {
if (item->masked || !item->Selectable()) return false;
value = item->result;
return true;
}
y -= item_height;
}
return false;
}
void DrawWidget(const Rect &r, WidgetID widget) const override
{
if (widget != WID_DM_ITEMS) return;
Colours colour = this->GetWidget(widget)->colour;
Rect ir = r.Shrink(WidgetDimensions::scaled.dropdownlist);
int y = ir.top;
int pos = this->vscroll->GetPosition();
for (const auto &item : this->list) {
int item_height = item->Height();
/* Skip items that are scrolled up */
if (--pos >= 0) continue;
if (y + item_height - 1 <= ir.bottom) {
Rect full{ir.left, y, ir.right, y + item_height - 1};
bool selected = (this->selected_result == item->result) && item->Selectable();
if (selected) GfxFillRect(full, PC_BLACK);
item->Draw(full, full.Shrink(WidgetDimensions::scaled.dropdowntext, RectPadding::zero), selected, colour);
}
y += item_height;
}
}
void OnClick([[maybe_unused]] Point pt, WidgetID widget, [[maybe_unused]] int click_count) override
{
if (widget != WID_DM_ITEMS) return;
int item;
if (this->GetDropDownItem(item)) {
this->click_delay = 4;
this->selected_result = item;
this->SetDirty();
}
}
/** Rate limit how fast scrolling happens. */
IntervalTimer scroll_interval = {std::chrono::milliseconds(30), [this](auto) {
if (this->scrolling == 0) return;
if (this->vscroll->UpdatePosition(this->scrolling)) this->SetDirty();
this->scrolling = 0;
}};
void OnMouseLoop() override
{
if (this->click_delay != 0 && --this->click_delay == 0) {
/* Close the dropdown, so it doesn't affect new window placement.
* Also mark it dirty in case the callback deals with the screen. (e.g. screenshots). */
this->Close();
this->parent->OnDropdownSelect(this->parent_button, this->selected_result);
return;
}
if (this->drag_mode) {
int item;
if (!_left_button_clicked) {
this->drag_mode = false;
if (!this->GetDropDownItem(item)) {
if (this->instant_close) this->Close();
return;
}
this->click_delay = 2;
} else {
if (_cursor.pos.y <= this->top + 2) {
/* Cursor is above the list, set scroll up */
this->scrolling = -1;
return;
} else if (_cursor.pos.y >= this->top + this->height - 2) {
/* Cursor is below list, set scroll down */
this->scrolling = 1;
return;
}
if (!this->GetDropDownItem(item)) return;
}
if (this->selected_result != item) {
this->selected_result = item;
this->SetDirty();
}
}
}
};
/**
* Determine width and height required to fully display a DropDownList
* @param list The list.
* @return Dimension required to display the list.
*/
Dimension GetDropDownListDimension(const DropDownList &list)
{
Dimension dim{};
for (const auto &item : list) {
dim.height += item->Height();
dim.width = std::max(dim.width, item->Width());
}
dim.width += WidgetDimensions::scaled.dropdowntext.Horizontal();
return dim;
}
/**
* Show a drop down list.
* @param w Parent window for the list.
* @param list Prepopulated DropDownList.
* @param selected The initially selected list item.
* @param button The widget which is passed to Window::OnDropdownSelect and OnDropdownClose.
* Unless you override those functions, this should be then widget index of the dropdown button.
* @param wi_rect Coord of the parent drop down button, used to position the dropdown menu.
* @param instant_close Set to true if releasing mouse button should close the
* list regardless of where the cursor is.
*/
void ShowDropDownListAt(Window *w, DropDownList &&list, int selected, WidgetID button, Rect wi_rect, Colours wi_colour, bool instant_close)
{
CloseWindowByClass(WC_DROPDOWN_MENU);
new DropdownWindow(w, std::move(list), selected, button, wi_rect, instant_close, wi_colour);
}
/**
* Show a drop down list.
* @param w Parent window for the list.
* @param list Prepopulated DropDownList.
* @param selected The initially selected list item.
* @param button The widget within the parent window that is used to determine
* the list's location.
* @param width Override the minimum width determined by the selected widget and list contents.
* @param instant_close Set to true if releasing mouse button should close the
* list regardless of where the cursor is.
*/
void ShowDropDownList(Window *w, DropDownList &&list, int selected, WidgetID button, uint width, bool instant_close)
{
/* Our parent's button widget is used to determine where to place the drop
* down list window. */
NWidgetCore *nwi = w->GetWidget(button);
Rect wi_rect = nwi->GetCurrentRect();
Colours wi_colour = nwi->colour;
if ((nwi->type & WWT_MASK) == NWID_BUTTON_DROPDOWN) {
nwi->disp_flags |= ND_DROPDOWN_ACTIVE;
} else {
nwi->SetLowered(true);
}
nwi->SetDirty(w);
if (width != 0) {
if (_current_text_dir == TD_RTL) {
wi_rect.left = wi_rect.right + 1 - ScaleGUITrad(width);
} else {
wi_rect.right = wi_rect.left + ScaleGUITrad(width) - 1;
}
}
ShowDropDownListAt(w, std::move(list), selected, button, wi_rect, wi_colour, instant_close);
}
/**
* Show a dropdown menu window near a widget of the parent window.
* The result code of the items is their index in the \a strings list.
* @param w Parent window that wants the dropdown menu.
* @param strings Menu list, end with #INVALID_STRING_ID
* @param selected Index of initial selected item.
* @param button Button widget number of the parent window \a w that wants the dropdown menu.
* @param disabled_mask Bitmask for disabled items (items with their bit set are displayed, but not selectable in the dropdown list).
* @param hidden_mask Bitmask for hidden items (items with their bit set are not copied to the dropdown list).
* @param width Minimum width of the dropdown menu.
*/
void ShowDropDownMenu(Window *w, const StringID *strings, int selected, WidgetID button, uint32_t disabled_mask, uint32_t hidden_mask, uint width)
{
DropDownList list;
for (uint i = 0; strings[i] != INVALID_STRING_ID; i++) {
if (!HasBit(hidden_mask, i)) {
list.push_back(std::make_unique(strings[i], i, HasBit(disabled_mask, i)));
}
}
if (!list.empty()) ShowDropDownList(w, std::move(list), selected, button, width);
}