Interface

Interfaces are built in the editor’s interface tab. In code, an interface and its elements are referred to by name:

Ui::Element loja = Ui::get("Loja");
loja["Moedas"].setText("Moedas: 12");
loja["Fechar"].onClick(this, [] { Ui::hide("Loja"); });
loja.show();

Ui::Element is just an address: it is cheap to copy and to keep, and each call looks the element up again. A name that doesn’t exist logs an error to the Output (once) and the call does nothing.

Interfaces

Function	What it does	Example
`Ui::Element Ui::get(std::string_view ui)`	The interface with that name.	`Ui::Element hud = Ui::get("Hud");`
`void Ui::show(std::string_view ui)`	Shows the interface, on top of the ones already on screen.	`Ui::show("Pausa");`
`void Ui::hide(std::string_view ui)`	Hides the interface. What the code changed in it still holds.	`Ui::hide("Pausa");`
`bool Ui::visible(std::string_view ui)`	`true` if the interface is on screen.	`if (Ui::visible("Loja")) ...`
`void Ui::reset(std::string_view ui)`	Puts the interface back the way it is in the editor and removes the `onClick` handlers.	`Ui::reset("Loja");`
`bool Ui::mouseOver()`	`true` if the mouse is over a button or a panel of the interface.	`if (!Ui::mouseOver()) atirar = true;`

Elements

The methods of Ui::Element. The ones that start with set can be chained: botao.setText("Comprado").setEnabled(false);

Function	What it does	Example
`Element operator[](std::string_view name)`	An element inside, by name: direct children first, then the ones inside them.	`hud["Moedas"]`
`bool exists()`	`true` if the interface or the element exists.	`if (loja["Item3"].exists()) ...`
`setText(std::string_view text)` e `text()`	The text of a Texto or a Botão.	`hud["Moedas"].setText("12");`
`setValue(float value)` e `value()`	How full a Barra is, from 0 to 1.	`hud["Vida"].setValue(0.5f);`
`setVisible(bool visible)`, `show()`, `hide()` e `visible()`	Shows or hides the whole interface or one element (with what is inside it).	`hud["Chave"].show();`
`setEnabled(bool enabled)` e `enabled()`	Button: disabled, it is dimmed and does not respond.	`botao.setEnabled(moedas >= 10);`
`setSprite(std::string_view sprite, int frame = 0)` e `setFrame(int frame)`	Changes the sprite of an Imagem (or the background of a Painel or Botão) and the frame.	`linha["Icone"].setSprite("espada");`
`setColor(Color color)`	The main color: the background of a Painel and a Botão, the filled part of a Barra, the letters of a Texto.	`hud["Vida"].setColor(colors::red);`
`setTextColor(Color color)` e `setBorderColor(Color color)`	The color of the letters and of the border.	`botao.setTextColor(colors::yellow);`
`setFont(std::string_view font, int size = 0)` e `setTextSize(int size)`	The font (a project font; `""` is the built-in one) and the size in pixels.	`titulo.setFont("Titulos", 24);`
`setPosition(float x, float y)` e `setSize(float width, float height)`	The position (from the anchor) and the size, in game pixels.	`hud["Seta"].setPosition(10, 40);`
`Element clone(std::string_view name)`	Copies the element (with what is inside it) into the same panel, at the end of the list, visible. With a name that already exists, it rebuilds the copy.	`modelo.clone("Item0");`
`void remove()`	Removes the element from the interface.	`loja["Itens"]["Item0"].remove();`
`onClick(const Entity* owner, std::function<void()> callback)`	Runs `callback` when the button is pressed. With `owner` (pass `this`), the handler goes away when the instance is destroyed.	`botao.onClick(this, [this] { restart(); });`
`setScroll(float pixels)` and `scroll()`	How far the list of a Panel with Rolar (scroll) is scrolled, in pixels (0 = at the start). The mouse wheel already scrolls it by itself.	`lista.setScroll(0);`
`onMouseEnter(const Entity* owner, std::function<void()> callback)` and `onMouseLeave(...)`	Runs `callback` when the mouse enters the element and when it leaves it.	`linha.onMouseEnter(this, [linha] { linha.setColor(colors::yellow); });`

Pausing

Function	What it does	Example
`void setPaused(bool paused)`	Pauses or resumes the game. While paused, instances don’t run timers, `onUpdate`, movement or collisions.	`setPaused(true);`
`bool paused()`	`true` if the game is paused.	`if (paused()) ...`
`void onPausedUpdate()`	Instance event: once per step while the game is paused, instead of `onUpdate`.	`void onPausedUpdate() override;`

Notes

Each interface exists only once while the game runs. Hiding and showing doesn’t undo what the code changed; for that, use Ui::reset.
The interfaces checked under Interfaces, in the room Inspector, open with it and close when leaving it. The ones the code shows stay until the code hides them.
With the mouse over a button or a panel with a background, mousePressed, mouseHeld and mouseReleased return false to the game.
The mouse works on the buttons of every visible interface; what is in front covers what is behind. The keyboard moves through the buttons of the front interface, with the cima, baixo, esquerda, direita and confirmar actions.
Changing rooms (or restarting) removes the pause.
onClick without owner also exists, and holds until a Ui::reset. Prefer passing this.

See HUD and pause menu and Shop with a list of items.