Class Component

Namespace

MiniTui

Assembly

MiniTui.dll

A piece of UI that holds state, handles keys and renders itself every frame (§9.1). Components stay immediate-mode: a parent renders its children explicitly with ctx.Render(child, buf, rect), which also records where the child is for the mouse.

[SuppressMessage("Design", "CA1001:Types that own disposable fields should be disposable", Justification = "The lifetime source is disposed at unmount, which the screen and overlay stacks control.")]
public abstract class Component

Inheritance

object

Component

Derived

Overlay

Screen

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Remarks

Every callback runs on the UI thread. A parent mounts before its children; children unmount before their parent, in reverse add order, and Lifetime is cancelled before OnUnmount() runs.

Constructors

Component()

Create a component.

protected Component()

Properties

App

The app, from mount to unmount.

protected App App { get; }

Property Value

App

Exceptions

InvalidOperationException

The component isn't mounted.

Area

The area the component was last rendered in through Render(Component, Buffer, Rect), or by the app (the top screen and overlays). default (an empty rect) until then.

public Rect Area { get; }

Property Value

Rect

CapturesText

True for text inputs: while this component is the innermost focused one, its ancestors' and the app's single-character bindings (without Ctrl or Alt) are skipped, so typing q doesn't quit.

public virtual bool CapturesText { get; }

Property Value

bool

Focus

This component's focusable children, in tab order. Empty by default.

protected FocusScope Focus { get; }

Property Value

FocusScope

HasSelection

True while the component has something selected to copy, such as a selectable ScrollState: Ctrl+C then goes to its HandleKey(ConsoleKeyInfo) instead of quitting, as it does for one that captures text.

public virtual bool HasSelection { get; }

Property Value

bool

Keys

This component's key bindings, tried after HandleKey(ConsoleKeyInfo).

public KeyMap Keys { get; }

Property Value

KeyMap

KeysGroup

The heading for this component's bindings in the help overlay.

public virtual string KeysGroup { get; }

Property Value

string

Lifetime

Cancelled when the component unmounts.

protected CancellationToken Lifetime { get; }

Property Value

CancellationToken

Exceptions

InvalidOperationException

The component isn't mounted.

Methods

AddChild<T>(T)

Add a child. If this component is mounted, the child mounts now (and activates, if this one is active).

protected T AddChild<T>(T child) where T : Component

Parameters

child T

Returns

T

Type Parameters

T

Exceptions

InvalidOperationException

The child already has a parent.

From(Action<Buffer, Rect, RenderContext>, Func<ConsoleKeyInfo, bool>?, bool)

An inline component, for small apps that want focus handling without writing a class.

public static Component From(Action<Buffer, Rect, RenderContext> render, Func<ConsoleKeyInfo, bool>? handleKey = null, bool capturesText = false)

Parameters

render Action<Buffer, Rect, RenderContext>

handleKey Func<ConsoleKeyInfo, bool>

capturesText bool

Returns

Component

HandleKey(ConsoleKeyInfo)

Handle a key before Keys. Return true if handled.

public virtual bool HandleKey(ConsoleKeyInfo key)

Parameters

key ConsoleKeyInfo

Returns

bool

HandleMouse(MouseEvent)

Handle a mouse event inside this component's Area (1.x spec §4.7). Return true if handled; otherwise the event goes on to the component's parent, and is dropped if nothing handles it. A press has already focused the component when this runs.

public virtual bool HandleMouse(MouseEvent mouse)

Parameters

mouse MouseEvent

Returns

bool

HandlePaste(string)

Handle pasted text, such as with Paste(string). Return true if handled; otherwise the paste goes on to the component's parent, and is dropped if nothing handles it.

public virtual bool HandlePaste(string text)

Parameters

text string

Returns

bool

Load<T>(Loadable<T>, Func<CancellationToken, Task<T>>)

Start a load that's cancelled, and whose result is ignored, once this component unmounts.

protected void Load<T>(Loadable<T> target, Func<CancellationToken, Task<T>> fetch)

Parameters

target Loadable<T>

fetch Func<CancellationToken, Task<T>>

Type Parameters

T

OnActivated()

Called when its screen (or overlay) becomes the top one.

protected virtual void OnActivated()

OnDeactivated()

Called when its screen is covered or popped (or its overlay closes).

protected virtual void OnDeactivated()

OnMount()

Called when the component is mounted, before its children.

protected virtual void OnMount()

OnUnmount()

Called when the component unmounts, after its children and after Lifetime is cancelled.

protected virtual void OnUnmount()

RemoveChild(Component)

Remove a child: it deactivates, unmounts and leaves Focus.

protected void RemoveChild(Component child)

Parameters

child Component

Exceptions

InvalidOperationException

It isn't a child of this component.

Render(Buffer, Rect, RenderContext)

Draw the component. Called every frame its parent renders it.

public abstract void Render(Buffer buf, Rect area, RenderContext ctx)

Parameters

buf Buffer

area Rect

ctx RenderContext