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core.view

Base view.

local view = require "core.view"

__index​

(field) __index: core.object

Base class providing OOP functionality for Lua. All classes in Pragtical inherit from Object.

current_scale​

(field) current_scale: number

h_scrollbar​

(field) h_scrollbar: core.scrollbar

Scrollable viewport indicator with draggable thumb. Supports both vertical and horizontal orientation with configurable alignment. Uses a "normal" coordinate system internally that treats all scrollbars as vertical-end-aligned, then transforms to the actual orientation/alignment.

hovered_scrollbar​

(field) hovered_scrollbar: boolean

scrollable​

(field) scrollable: boolean

size​

(field) size: core.view.position

super​

(field) super: core.object

Base class providing OOP functionality for Lua. All classes in Pragtical inherit from Object.

v_scrollbar​

(field) v_scrollbar: core.scrollbar

Scrollable viewport indicator with draggable thumb. Supports both vertical and horizontal orientation with configurable alignment. Uses a "normal" coordinate system internally that treats all scrollbars as vertical-end-aligned, then transforms to the actual orientation/alignment.

core.view.context​

core.view.context:
    | 'application'
    | 'session'

core.view.cursor​

core.view.cursor:
    | 'arrow'
    | 'ibeam'
    | 'sizeh'
    | 'sizev'
    | 'hand'

core.view.mousebutton​

core.view.mousebutton:
    | 'left'
    | 'right'

core.view.position​

x​

(field) x: number

y​

(field) y: number

core.view.scroll​

to​

(field) to: core.view.position

x​

(field) x: number

y​

(field) y: number

core.view.scrollbar​

h​

(field) h: core.view.thumbtrack

w​

(field) w: core.view.thumbtrackwidth

x​

(field) x: core.view.thumbtrack

y​

(field) y: core.view.thumbtrack

core.view.thumbtrack​

thumb​

(field) thumb: number

track​

(field) track: number

core.view.thumbtrackwidth​

thumb​

(field) thumb: number

to​

(field) to: core.view.thumbtrack

track​

(field) track: number

from_state​

function core.view.from_state(state: table)
  -> view: (core.view)?

Create and initialize a new view instance from a previously saved state.

This function is called when restoring workspace/session state. Implementations are responsible for:

  • creating the view instance
  • applying any persisted state

If loading the instance failed nil will be returned.

__call​

(method) core.object:__call(...any)
  -> obj: core.object

Metamethod allowing class to be called like a constructor. Enables syntax: local obj = MyClass(args) instead of MyClass:new(args) Automatically creates instance and calls new() with provided arguments.

@return obj — The new instance of the class

__tostring​

(method) core.view:__tostring()
  -> string

clamp_scroll_position​

(method) core.view:clamp_scroll_position()

Clamp scroll position to valid range (0 to max scrollable size). Called automatically by update(). Override get_scrollable_size() to customize.

draw​

(method) core.view:draw()

Called every frame to render the view. Override to draw custom content. Typical pattern:

  1. Call self:draw_background(color)
  2. Draw your content
  3. Call self:draw_scrollbar()

draw_background​

(method) core.view:draw_background(color: renderer.color)

Draw a solid background color for the entire view. Commonly called at the start of draw() methods.

draw_scrollbar​

(method) core.view:draw_scrollbar()

Draw the view's scrollbars. Commonly called at the end of draw() methods.

extend​

(method) core.object:extend()
  -> cls: core.object

Create a new class that inherits from this one. Returns a new class with this class as its parent. Example: local MyClass = Object:extend()

@return cls — The new class table

extends​

(method) core.object:extends(T: any)
  -> extends: boolean

Check if object inherits from the given type (inheritance-aware). Use this to check class hierarchy. Example: view:extends(View) returns true for View and all subclasses

@param T — Class to check inheritance from

@return extends — True if object is T or inherits from T

get_content_bounds​

(method) core.view:get_content_bounds()
  -> x1: number
  2. y1: number
  3. x2: number
  4. y2: number

Get the content bounds in content coordinates (accounting for scroll).

@return x1 — Left edge

@return y1 — Top edge

@return x2 — Right edge

@return y2 — Bottom edge

get_content_offset​

(method) core.view:get_content_offset()
  -> x: number
  2. y: number

Get the top-left corner of content area in screen coordinates. Accounts for scroll offset. Use for drawing content at correct position.

@return x — Screen x coordinate

@return y — Screen y coordinate

get_h_scrollable_size​

(method) core.view:get_h_scrollable_size()
  -> width: number

Get the total scrollable width of the view's content. Used by horizontal scrollbar.

@return width — Width in pixels (default: 0, no horizontal scroll)

get_module​

(method) core.view:get_module()
  -> path: string?

Returns the module path of this view.

This method resolves the Lua module name that loaded the concrete view class (for example "core.view").

If the view class cannot be associated with any loaded module, nil is returned.

get_name​

(method) core.view:get_name()
  -> name: string

Get the name displayed in the view's tab. Override to show document name, file path, etc.

get_scrollable_size​

(method) core.view:get_scrollable_size()
  -> height: number

Get the total scrollable height of the view's content. Used by scrollbar to calculate thumb size and position.

@return height — Height in pixels (default: infinite)

get_state​

(method) core.view:get_state()
  -> state: table?

Serialize this view into a persistable state table.

This method is called when the editor is saving workspace/session state. The returned table must contain only plain Lua data (no functions, userdata, metatables, or cyclic references).

Returning nil indicates that this view should NOT be restored when reloading the workspace.

is​

(method) core.object:is(T: any)
  -> is_exact: boolean

Check if object is exactly of the given type (no inheritance check). Use this for strict type matching. Example: view:is(DocView) returns true only if view is a DocView, not a subclass

@param T — Class to check against

@return is_exact — True if object is exactly type T

is_class_of​

(method) core.object:is_class_of(T: any)
  -> is_instance: boolean

Check if the given object is exactly an instance of this class. Inverse of is() - checks if T is an instance of self. Example: DocView:is_class_of(obj) checks if obj is exactly a DocView

@param T — Object to check

@return is_instance — True if T is exactly an instance of this class

is_extended_by​

(method) core.object:is_extended_by(T: any)
  -> is_extended: boolean

Check if the given object/class inherits from this class. Inverse of extends() - checks if T is a subclass of self. Example: View:is_extended_by(DocView) checks if DocView inherits from View

@param T — Object or class to check

@return is_extended — True if T inherits from this class

move_towards​

(method) core.view:move_towards(t: table, k: string|number, dest: number, rate?: number, name?: string)

Smoothly animate a value towards a destination. Use this for animations instead of direct assignment.

@param t — Table containing the value

@param k — Key in table

@param dest — Target value

@param rate — Animation speed (0-1, default 0.5, higher = faster)

@param name — Transition name (for config.disabled_transitions)

new​

(method) core.view:new()

Constructor - initializes a new view instance. Override this in subclasses and always call super constructor first: MyView.super.new(self)

on_file_dropped​

(method) core.view:on_file_dropped(filename: string, x: number, y: number)
  -> consumed: boolean

Handle file drop events (drag and drop from OS). Override to handle dropped files. Return true to consume event.

@param filename — Absolute path to dropped file

@param x — Screen x where file was dropped

@param y — Screen y where file was dropped

@return consumed — True to consume event, false to propagate

on_ime_text_editing​

(method) core.view:on_ime_text_editing(text: string, start: number, length: number)

Handle IME (Input Method Editor) text composition events. Override for IME support in text editors. Called during composition.

@param text — Composition text being edited

@param start — Start position of selection within composition

@param length — Length of selection within composition

on_mouse_left​

(method) core.view:on_mouse_left()

Called when mouse leaves the view's area. Override to clear hover states. Base implementation notifies scrollbars.

on_mouse_moved​

(method) core.view:on_mouse_moved(x: number, y: number, dx: number, dy: number)
  -> boolean|nil

Handle mouse movement events. Override for hover effects, drag operations, etc. Base implementation handles scrollbar dragging.

@param x — Current screen x coordinate

@param y — Current screen y coordinate

@param dx — Delta x since last move

@param dy — Delta y since last move

on_mouse_pressed​

(method) core.view:on_mouse_pressed(button: 'left'|'right', x: number, y: number, clicks: integer)
  -> consumed: boolean?

Handle mouse button press events. Override to handle clicks. Return true to consume event and prevent propagation. Base implementation handles scrollbar clicks.

@param x — Screen x coordinate

@param y — Screen y coordinate

@param clicks — Number of consecutive clicks (configurable with config.max_clicks)

@return consumed — True to consume event, false/nil to propagate

button:
    | 'left'
    | 'right'

on_mouse_released​

(method) core.view:on_mouse_released(button: 'left'|'right', x: number, y: number)

Handle mouse button release events. Override to handle click completion. Base implementation handles scrollbar.

@param x — Screen x coordinate

@param y — Screen y coordinate

button:
    | 'left'
    | 'right'

on_mouse_wheel​

(method) core.view:on_mouse_wheel(y: number, x: number)
  -> consumed: boolean?

Handle mouse wheel scroll events. Override for custom scroll behavior. Base implementation does nothing.

@param y — Vertical scroll delta; positive is "up"

@param x — Horizontal scroll delta; positive is "left"

@return consumed — True to consume event

on_scale_change​

(method) core.view:on_scale_change(new_scale: number, prev_scale: number)

Called when DPI scale changes (display moved, zoom changed, etc.). Override to adjust sizes, padding, or other scale-dependent values.

@param new_scale — New scale factor (e.g., 1.0, 1.5, 2.0)

@param prev_scale — Previous scale factor

on_text_input​

(method) core.view:on_text_input(text: string)

Handle text input events (typing, IME composition). Override for text editing. Called after IME composition completes.

@param text — Input text (may be multiple characters)

on_touch_moved​

(method) core.view:on_touch_moved(x: number, y: number, dx: number, dy: number, i: number)

Handle touch move events (touchscreen/trackpad gestures). Override for touch-specific behavior. Base implementation handles scrolling.

@param x — Current touch x coordinate

@param y — Current touch y coordinate

@param dx — Delta x since last position

@param dy — Delta y since last position

@param i — Touch finger/pointer index

scrollbar_dragging​

(method) core.view:scrollbar_dragging()
  -> dragging: boolean

Check if user is currently dragging either scrollbar.

@return dragging — True if scrollbar drag is in progress

scrollbar_hovering​

(method) core.view:scrollbar_hovering()
  -> hovering: boolean

Check if mouse is hovering over either scrollbar track.

@return hovering — True if mouse is over scrollbar

scrollbar_overlaps_point​

(method) core.view:scrollbar_overlaps_point(x: number, y: number)
  -> overlaps: boolean

Check if a screen point overlaps either scrollbar. Useful for determining cursor style or handling clicks.

@param x — Screen x coordinate

@param y — Screen y coordinate

@return overlaps — True if point is over vertical or horizontal scrollbar

supports_text_input​

(method) core.view:supports_text_input()
  -> boolean

Whether this view accepts text input (enables IME). Override and return true for text editors and input fields.

try_close​

(method) core.view:try_close(do_close: function)

Called when view is requested to close (e.g., tab close button). Override to show confirmation dialogs for unsaved changes. Example: core.command_view:enter("Save?", \{submit = do_close\})

@param do_close — Call this function to actually close the view

update​

(method) core.view:update()

Called every frame to update view state. Override to add custom update logic. Always call super.update(self) first. Handles: scale changes, scroll animation, scrollbar updates.

update_scrollbar​

(method) core.view:update_scrollbar()

Update scrollbar positions and sizes. Called automatically by update(). Rarely needs to be called manually.