# device_query
[](https://travis-ci.org/ostrosco/device_query)
A simple library to query mouse and keyboard inputs on demand without a window.
Will work in Windows, Linux on X11, and macOS.
```Rust
use device_query::{DeviceQuery, DeviceState, MouseState, Keycode};
let device_state = DeviceState::new();
let mouse: MouseState = device_state.get_mouse();
println!("Current Mouse Coordinates: {:?}", mouse.coords);
let keys: Vec<Keycode> = device_state.get_keys();
println!("Is A pressed? {}", keys.contains(Keycode::A));
```
# Dependencies
Windows shouldn't require any special software to be installed for `device_query` to work properly.
On Linux, the X11 development libraries are required for `device_query` to query state from the OS.
On Ubuntu/Debian:
```
sudo apt install libx11-dev
```
On Fedora/RHEL/CentOS:
```
sudo dnf install xorg-x11-server-devel
```
On newer versions of MacOS, you may run into issues where you only see meta keys such as shift,
backspace, et cetera. This is due to a permission issue. To work around this:
* open the MacOS system preferences
* go to Security -> Privacy
* scroll down to Accessibility and unlock it
* add the app that is using `device_query` (such as your terminal) to the list
# Device Callbacks
`device_query` allows you to register callbacks for various device events such as key presses and mouse movements.
## Example
Here's a simple example demonstrating how to use the callback system:
```rust
extern crate device_query;
use device_query::{DeviceEvents, DeviceEventsHandler, Keycode, MouseButton, MousePosition};
use std::thread;
use std::time::Duration;
fn main() {
// Initialize the event handler with a sleep duration of 10 milliseconds
let event_handler = DeviceEventsHandler::new(Duration::from_millis(10))
.expect("Could not initialize event loop");
// Register callbacks for various events
// The callbacks will be automatically deregistered when they go out of scope
let _mouse_move_guard = event_handler.on_mouse_move(|position: &MousePosition| {
println!("Mouse moved to position: {:?}", position);
});
// Keep the main thread alive to continue receiving events
loop {
thread::sleep(Duration::from_secs(1000));
}
}
```