From 5fde013747e9cec3460d04b77a8d52729c051602 Mon Sep 17 00:00:00 2001
From: rhysd <lin90162@yahoo.co.jp>
Date: Fri, 17 Jun 2022 02:07:12 +0900
Subject: [PATCH] add `single_line` example

---
 Cargo.toml              |  4 ++
 README.md               |  3 ++
 examples/single_line.rs | 88 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 95 insertions(+)
 create mode 100644 examples/single_line.rs

diff --git a/Cargo.toml b/Cargo.toml
index ec44c31..0ddc75d 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -28,3 +28,7 @@ required-features = ["crossterm"]
 [[example]]
 name = "multi"
 required-features = ["crossterm"]
+
+[[example]]
+name = "single_line"
+required-features = ["crossterm"]
diff --git a/README.md b/README.md
index 565ad15..20de35c 100644
--- a/README.md
+++ b/README.md
@@ -50,6 +50,7 @@ cargo run --example minimal
 - [minimal](./examples/minimal.rs): Minimal usage with [crossterm][] support
 - [termion](./examples/termion.rs): Minimal usage with [termion][] support
 - [multi](./examples/multi.rs): Two split textareas in a screen and switch them
+- [single_line](./examples/single_line.rs): Single line input form with float number validation
 - [editor](./examples/editor.rs): Simple text editor to edit multiple files
 
 ## Minimal Usage
@@ -284,6 +285,8 @@ loop {
 let text = textarea.into_lines().remove(0); // Get input text
 ```
 
+See [`single_line` example](./examples/single_line.rs) for working example.
+
 ### Define your own key mappings
 
 All editor operations are defined as public methods of `TextArea`. To move cursor, use `tui_textarea::CursorMove` to
diff --git a/examples/single_line.rs b/examples/single_line.rs
new file mode 100644
index 0000000..b47aa0a
--- /dev/null
+++ b/examples/single_line.rs
@@ -0,0 +1,88 @@
+use crossterm::event::{DisableMouseCapture, EnableMouseCapture};
+use crossterm::terminal::{
+    disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen,
+};
+use std::io;
+use tui::backend::CrosstermBackend;
+use tui::layout::{Constraint, Layout};
+use tui::style::{Color, Style};
+use tui::widgets::{Block, Borders};
+use tui::Terminal;
+use tui_textarea::{Input, Key, TextArea};
+
+fn update(textarea: &mut TextArea) -> bool {
+    if let Err(err) = textarea.lines()[0].parse::<f64>() {
+        textarea.set_style(Style::default().fg(Color::LightRed));
+        textarea.set_block(
+            Block::default()
+                .borders(Borders::ALL)
+                .title(format!("ERROR: {}", err)),
+        );
+        false
+    } else {
+        textarea.set_style(Style::default().fg(Color::LightGreen));
+        textarea.set_block(Block::default().borders(Borders::ALL).title("OK"));
+        true
+    }
+}
+
+fn main() -> io::Result<()> {
+    let stdout = io::stdout();
+    let mut stdout = stdout.lock();
+
+    enable_raw_mode()?;
+    crossterm::execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
+    let mut term = Terminal::new(backend)?;
+
+    let mut textarea = TextArea::default();
+    textarea.set_block(
+        Block::default()
+            .borders(Borders::ALL)
+            .title("Single Line Input"),
+    );
+    textarea.set_cursor_line_style(Style::default());
+    let layout =
+        Layout::default().constraints([Constraint::Length(3), Constraint::Min(1)].as_slice());
+    let mut is_valid = update(&mut textarea);
+
+    loop {
+        term.draw(|f| {
+            let chunks = layout.split(f.size());
+            let widget = textarea.widget();
+            f.render_widget(widget, chunks[0]);
+        })?;
+
+        match Input::from(crossterm::event::read()?) {
+            Input { key: Key::Esc, .. } => break,
+            Input {
+                key: Key::Enter, ..
+            } if is_valid => break,
+            Input {
+                key: Key::Char('m'),
+                ctrl: true,
+                ..
+            }
+            | Input {
+                key: Key::Enter, ..
+            } => {}
+            input => {
+                // TextArea::input returns if the input modified its text
+                if textarea.input(input) {
+                    is_valid = update(&mut textarea);
+                }
+            }
+        }
+    }
+
+    disable_raw_mode()?;
+    crossterm::execute!(
+        term.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    term.show_cursor()?;
+
+    println!("Input: {:?}", textarea.lines()[0]);
+    Ok(())
+}