Add checkbox

examples/checkbox.rs

@@ -0,0 +1,14 @@
+extern crate inquirer;
+
+fn main() {
+    let choices = &["Pepperoni", "Ham", "Pineapple"];
+
+    match inquirer::checkbox("Choose your toppings:", choices) {
+        Ok(result) => println!("You chose {:?}.", result),
+        Err(inquirer::Error::UserAborted) => {
+            println!("Pressed Ctrl-C, exiting.");
+            std::process::exit(1);
+        }
+        Err(err) => println!("{:?}", err),
+    }
+}

src/checkbox.rs

@@ -0,0 +1,136 @@
+use std::io::{Write, stdout, stdin};
+use termion::{TermRead, TermWrite, IntoRawMode, color, Style, Key};
+
+use choice::Choice;
+use error::Error;
+
+/// Render a checkbox style list the user can select multiple value from.
+///
+/// The return type is a `Result` that contain a vector of references to results
+/// or a custom error. **Please note:** If the user presses
+/// <kbd>Ctrl</kbd><kbd>C</kbd>, this will result in an `UserAborted` error that
+/// the application should handle.
+///
+/// # Examples
+///
+/// Simple example, using only string slices for options.
+///
+/// ```rust,no_run
+/// extern crate inquirer;
+///
+/// let choices =  &["Pepperoni", "Ham", "Pineapple"];
+/// let result = inquirer::checkbox("What topppings would you like?", choices).unwrap();
+/// ```
+///
+/// ## Complex types
+///
+/// You can also use tuples for options, where the first item is printed to the
+/// screen, but the second item is returned as the value of the selection.
+///
+/// ```rust,no_run
+/// # extern crate inquirer;
+/// let choices =  &[("Alpha", 1), ("Beta", 2), ("Gamma", 3)];
+/// let result = inquirer::checkbox("Choose an option:", choices).unwrap();
+/// ```
+///
+/// ## Error Handling
+///
+/// ```rust,no_run
+/// # extern crate inquirer;
+/// let choices =  &["Pepperoni", "Ham", "Pineapple"];
+///
+/// match inquirer::checkbox("Choose your toppings:", choices) {
+///     Ok(result) => println!("You chose {:?}.", result),
+///     Err(inquirer::Error::UserAborted) => {
+///         println!("Pressed Ctrl-C, exiting.");
+///         std::process::exit(1);
+///     }
+///     Err(err) => println!("{:?}", err)
+/// }
+/// ```
+pub fn checkbox<'c, C, V>(prompt: &str, choices: &'c [C]) -> Result<Vec<&'c V>, Error>
+    where C: Choice<Value = V>
+{
+    let stdin = stdin();
+    let mut stdout = try!(stdout().into_raw_mode());
+    try!(stdout.hide_cursor());
+
+    try!(stdout.color(color::Green));
+    print!("[?] ");
+    try!(stdout.reset());
+    println!("{} (Press <space> to select)", prompt);
+
+    let mut selected: Vec<_> = (0..choices.len()).map(|_| false).collect();
+
+    for _ in 0..choices.len() - 1 {
+        println!("");
+    }
+
+    let mut cur: usize = 0;
+
+    let mut input = stdin.keys();
+
+    loop {
+        try!(stdout.move_cursor_up(choices.len() as u32));
+        for (i, s) in choices.iter().enumerate() {
+            print!("\n\r");
+            try!(stdout.clear_line());
+
+            if cur == i {
+                try!(stdout.style(Style::Bold));
+                print!(" > ");
+            } else {
+                print!("   ");
+            }
+
+            if selected[i] {
+                try!(stdout.style(Style::Bold));
+                print!("● {}", s.text());
+                try!(stdout.reset());
+            } else {
+                print!("○ {}", s.text());
+            }
+
+            try!(stdout.reset());
+
+        }
+
+        try!(stdout.lock().flush());
+
+        let next = try!(input.next().ok_or_else(|| Error::NoMoreInput));
+
+        match try!(next) {
+            Key::Char('\n') => {
+                // Enter
+                break;
+            }
+            Key::Up if cur != 0 => {
+                cur -= 1;
+            }
+            Key::Down if cur != choices.len() - 1 => {
+                cur += 1;
+            }
+            Key::Char(' ') => selected[cur] = !selected[cur],
+            Key::Ctrl('c') => {
+                print!("\n\r");
+                try!(stdout.show_cursor());
+                return Err(Error::UserAborted);
+            }
+            _ => {
+                // pass
+            }
+        }
+    }
+
+    print!("\n\r");
+    try!(stdout.show_cursor());
+
+    Ok(choices.iter()
+        .zip(selected.iter())
+        .filter_map(|(choice, &selected)| if selected {
+            Some(choice.value())
+        } else {
+            None
+        })
+        .collect())
+}

src/lib.rs

@@ -17,8 +17,10 @@ mod choice;
 mod error;
 mod list;
 mod confirm;
+mod checkbox;
 
 pub use choice::Choice;
 pub use error::Error;
 pub use list::list;
 pub use confirm::confirm;
+pub use checkbox::checkbox;