e_window

e_window A window tool. Think WinAPI ShowMessageBox; but more than that.

feat(cargo-e): Integrate e_window for panic handling and structured output

Integrates the new e_window application into cargo-e to provide graphical panic windows and structured output display.

This enhancement introduces a robust mechanism for cargo-e to present error messages and other important information in a user-friendly GUI, rather than just console output. When a critical error or panic occurs, e_window can now be invoked by cargo-e to display the panic details in a dedicated, interactive window, improving user experience by providing clear, persistent feedback.

Key aspects of this integration and the new e_window application include:

Graphical Panic Reporting: cargo-e can now launch e_window to present detailed panic information, including stack traces and contextual data, in a dedicated GUI. This makes debugging and error reporting significantly more accessible to users. Structured Output Display: e_window is capable of parsing and presenting structured data (like key-value pairs, headers, and body text) from input, making it a versatile tool for displaying various forms of output beyond panics. Customizable Window Behavior: The window's title, size, and position can be configured programmatically or via arguments embedded in the input data itself, allowing cargo-e to tailor the error display. External Window Monitoring (Windows only): The e_window can optionally monitor another process's window (by HWND) and signal its closure, which can be useful for coordinated application behavior or debugging within cargo-e's ecosystem. This change significantly improves the diagnostic and user feedback capabilities of cargo-e.

Features

• Create and manage an eframe window with custom title, size, and position.
• Input or pipe text and display the parsed output in real time.
• Supports command-line options via CLI or as the first line of input.
• Optionally follow another window by HWND and beep when it closes (Windows only).

Getting Started

Prerequisites

• Rust (with cargo)
• A compatible version of the eframe and egui libraries (handled by Cargo)

Building the Project

From the workspace root or the addendum/e_window directory:

cargo build

Running the Application

From the addendum/e_window directory:

cargo run

Or, to run with custom options:

cargo run -- --title "My Window" --width 1024 --height 768

You can also pipe input:

echo "some text" | cargo run

Installing the Binary

If you want the e_window command available globally, install it from the workspace root:

cargo install --path addendum/e_window

Usage

You can launch e_window directly or use it as a library in your own project.

Command-Line Options

• --title <TITLE>: Set window title
• --width <WIDTH>: Set window width
• --height <HEIGHT>: Set window height
• --x <X>: Set window X position
• --y <Y>: Set window Y position
• --follow-hwnd <HWND>: (Windows only) Follow another window and beep when it closes
• -i, --input-file <FILE>: Read input data from file
• Any other positional arguments are treated as input text

You can also specify options as the first line of piped or file input.

Example

e_window --title "Demo" --width 900 --height 600

Or with piped input:

echo "--title Demo Window --width 900" | e_window

Pool Manager Mode

e_window includes a pool manager mode that allows you to automatically keep a specified number of windows open at all times. This is useful for testing, demonstrations, or any scenario where you want to ensure a persistent set of windows.

How It Works

• When you launch e_window with the --w-pool-cnt <N> option, a special pool manager GUI window is started.
• The pool manager is always on top and displays the current status of the window pool.
• The manager automatically spawns and tracks child windows, each with a unique index.
• If any child window is closed, the manager will re-spawn it to maintain the desired count.
• Closing the pool manager window will automatically close all managed child windows.

Pool Manager Options

• --w-pool-cnt <N>: Keep at least N windows open at all times.
• --w-pool-rate <MS>: Minimum milliseconds between opening new windows (default: 1000).
• --w-pool-ndx <N>: (internal) Index of this window instance (used by the manager for child windows).
• --manager-hwnd <HWND>: (internal) HWND of the pool manager window.

Example Usage

e_window --w-pool-cnt 4

July 2025

Keyboard Shortcuts

• Pressing Enter or Escape in the main card view closes the window (same as clicking OK).

Improved Scroll Behavior

• Scroll areas now use unique IDs to avoid egui warnings and ensure reliable scrolling.
• Scroll bars are always visible and support drag-to-scroll and arrow key navigation.

e_window_hydra Example

• Demonstrates advanced Win32 window management and automation for Chrome windows over a grid.
• Features robust grid mapping, dynamic topmost/z-order control, and automated modal closure via JS injection.
• Includes cross-platform mouse click simulation to grid cells, with all Win32 API usage encapsulated for maintainability.
• Useful for automated UI testing, demos, and interactive control of external applications.

position_grid_demo Example

• Shows how to use the PositionGrid utility for interactive grid-based input and diagnostics.
• Visualizes grid cell mapping, DPI scaling, and mouse click simulation within an eframe window.
• Includes detailed logging and diagnostics for grid geometry, cell selection, and input mapping.
• Ideal for learning, debugging, and validating grid-based UI logic in Rust/egui applications.

Real-Time Control Example and Supported Commands

e_window can process special control commands from stdin to update its window in real time. These commands must start with !control: and are parsed as structured instructions.

Supported Commands

• !control:exit
  Closes the window.

• !control:set_rect x y w h
  Sets the window rectangle to position (x, y) and size (w, h).

• !control:set_rect_eased x y w h duration_ms easing
  Animates the window rectangle to the given position and size over duration_ms milliseconds using the specified easing function.

• !control:set_title <title>
  Changes the window title.

• !control:begin_document
  Marks the start of a document.

• !control:end_document
  Marks the end of a document.

• !control:delay <milliseconds>
  Pauses processing for the specified number of milliseconds.

Any other line is treated as content and displayed in the window.

Example Usage

!control:set_rect 10 20 300 400
!control:set_rect_eased 10 20 300 400 500 ease-in-out
!control:set_title My Window
!control:begin_document
Some regular content line
!control:end_document
!control:delay 1000
!control:exit

These commands can be sent interactively or piped into e_window to control its behavior while running.

Take a look at the animated_control example for more detail.

Contributing

Contributions are welcome! Please open an issue or submit a pull request for suggestions, bug fixes, or improvements.

License

This project is licensed under the MIT License. See the LICENSE file for details.