Expose cursor position of InputField

src/views/input_field.rs

@@ -543,9 +543,13 @@ impl InputField {
     /// All rendering must be explicitely called, no rendering is
     /// done on functions changing the state.
     ///
+    /// This function also returns the cursor position in the form
+    /// `Ok(Some((left, top)))` if the terminal cursor is rendered.
+    /// Otherwise, this function returns `Ok(None)`.
+    ///
     /// w is typically either stderr or stdout. This function doesn't
     /// flush by itself (useful to avoid flickering)
-    pub fn display_on<W: Write>(&self, w: &mut W) -> Result<(), Error> {
+    pub fn display_on<W: Write>(&self, w: &mut W) -> Result<Option<(u16, u16)>, Error> {
         let normal_style = if self.focused {
             &self.focused_style
         } else {
@@ -554,6 +558,7 @@ impl InputField {
 
         let mut width = self.area.width as usize;
         let pos = self.content.cursor_pos();
+        let mut terminal_cursor_pos = None;
         let scrollbar = self
             .area
             .scrollbar(self.scroll.y as u16, self.content.line_count() as u16);
@@ -609,6 +614,11 @@ impl InputField {
                         if !is_last || displayed_width + char_width > width {
                             if self.focused && selection.contains(i, y) {
                                 self.cursor_style.queue(w, fit::ELLIPSIS)?;
+                                // set terminal cursor position
+                                terminal_cursor_pos = Some((
+                                    self.area.left + displayed_width as u16,
+                                    self.area.top + j,
+                                ));
                             } else {
                                 normal_style.queue(w, fit::ELLIPSIS)?;
                             }
@@ -618,6 +628,9 @@ impl InputField {
                     }
                     if self.focused && selection.contains(i, y) {
                         self.cursor_style.queue(w, c)?;
+                        // set terminal cursor position
+                        terminal_cursor_pos =
+                            Some((self.area.left + displayed_width as u16, self.area.top + j));
                     } else {
                         normal_style.queue(w, c)?;
                     }
@@ -628,6 +641,9 @@ impl InputField {
                 }
                 if displayed_width < width && cursor_at_end {
                     self.cursor_style.queue(w, ' ')?;
+                    // set terminal cursor position
+                    terminal_cursor_pos =
+                        Some((self.area.left + displayed_width as u16, self.area.top + j));
                     displayed_width += 1;
                 }
                 while displayed_width < width {
@@ -646,14 +662,14 @@ impl InputField {
                 }
             }
         }
-        Ok(())
+        Ok(terminal_cursor_pos)
     }
 
     /// render the input field on stdout
-    pub fn display(&self) -> Result<(), Error> {
+    pub fn display(&self) -> Result<Option<(u16, u16)>, Error> {
         let mut w = std::io::stdout();
-        self.display_on(&mut w)?;
+        let pos = self.display_on(&mut w)?;
         w.flush()?;
-        Ok(())
+        Ok(pos)
     }
 }