Add example for a virtual touchscreen

Author: zsameem

examples/virtual_touch_screen.rs

@@ -0,0 +1,53 @@
+use evdev::{
+    uinput::VirtualDeviceBuilder, AbsInfo, AbsoluteAxisCode, AttributeSet, EventType, InputEvent,
+};
+use evdev::{KeyCode, KeyEvent, UinputAbsSetup};
+use std::thread::sleep;
+use std::time::Duration;
+
+fn main() -> std::io::Result<()> {
+
+    // Size of the touch screen
+    let max_x = 1080;
+    let max_y = 1920;
+
+    let abs_setup_x = AbsInfo::new(0, 0, max_x, 0, 0, 0);
+    let abs_setup_y = AbsInfo::new(0, 0, max_y, 0, 0, 0);
+
+    // see https://www.kernel.org/doc/html/v4.17/input/event-codes.html
+    let mut buttons = AttributeSet::<KeyCode>::new();
+    buttons.insert(KeyCode::BTN_TOUCH);
+
+    let mut device = VirtualDeviceBuilder::new()?
+        .name("Fake TouchScreen")
+        .with_keys(&buttons)?
+        .with_absolute_axis(&UinputAbsSetup::new(AbsoluteAxisCode::ABS_X, abs_setup_x))?
+        .with_absolute_axis(&UinputAbsSetup::new(AbsoluteAxisCode::ABS_Y, abs_setup_y))?
+        .build()?;
+
+    for path in device.enumerate_dev_nodes_blocking()? {
+        let path = path?;
+        println!("Available as {}", path.display());
+    }
+
+    println!("Waiting for Ctrl-C...");
+
+    // Emit some touch events
+    for i in 0..10 {
+        for j in 0..10 {
+            let move_x = InputEvent::new_now(EventType::ABSOLUTE.0, AbsoluteAxisCode::ABS_X.0, i);
+            let move_y = InputEvent::new_now(EventType::ABSOLUTE.0, AbsoluteAxisCode::ABS_Y.0, j);
+            let down_event = *KeyEvent::new(KeyCode(KeyCode::BTN_TOUCH.0), 1);
+
+            device.emit(&[down_event, move_x, move_y]).unwrap();
+            println!("touching {i}, {j}");
+
+            let up_event = *KeyEvent::new(KeyCode(KeyCode::BTN_TOUCH.0), 0);
+            device.emit(&[up_event])?;
+            println!("releasing {i}, {j}");
+            sleep(Duration::from_millis(100));
+        }
+    }
+
+    Ok(())
+}