Move all crates into a crates directory (#1940)

crates/egui_demo_lib/src/demo/text_edit.rs

@@ -0,0 +1,111 @@
+/// Showcase [`TextEdit`].
+#[derive(PartialEq)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "serde", serde(default))]
+pub struct TextEdit {
+    pub text: String,
+}
+
+impl Default for TextEdit {
+    fn default() -> Self {
+        Self {
+            text: "Edit this text".to_owned(),
+        }
+    }
+}
+
+impl super::Demo for TextEdit {
+    fn name(&self) -> &'static str {
+        "🖹 TextEdit"
+    }
+
+    fn show(&mut self, ctx: &egui::Context, open: &mut bool) {
+        egui::Window::new(self.name())
+            .open(open)
+            .resizable(false)
+            .show(ctx, |ui| {
+                use super::View as _;
+                self.ui(ui);
+            });
+    }
+}
+
+impl super::View for TextEdit {
+    fn ui(&mut self, ui: &mut egui::Ui) {
+        let Self { text } = self;
+
+        ui.horizontal(|ui| {
+            ui.spacing_mut().item_spacing.x = 0.0;
+            ui.label("Advanced usage of ");
+            ui.code("TextEdit");
+            ui.label(".");
+        });
+
+        let output = egui::TextEdit::multiline(text)
+            .hint_text("Type something!")
+            .show(ui);
+
+        ui.horizontal(|ui| {
+            ui.spacing_mut().item_spacing.x = 0.0;
+            ui.label("Selected text: ");
+            if let Some(text_cursor_range) = output.cursor_range {
+                use egui::TextBuffer as _;
+                let selected_chars = text_cursor_range.as_sorted_char_range();
+                let selected_text = text.char_range(selected_chars);
+                ui.code(selected_text);
+            }
+        });
+
+        let anything_selected = output
+            .cursor_range
+            .map_or(false, |cursor| !cursor.is_empty());
+
+        ui.add_enabled(
+            anything_selected,
+            egui::Label::new("Press ctrl+Y to toggle the case of selected text (cmd+Y on Mac)"),
+        );
+
+        if ui
+            .input_mut()
+            .consume_key(egui::Modifiers::COMMAND, egui::Key::Y)
+        {
+            if let Some(text_cursor_range) = output.cursor_range {
+                use egui::TextBuffer as _;
+                let selected_chars = text_cursor_range.as_sorted_char_range();
+                let selected_text = text.char_range(selected_chars.clone());
+                let upper_case = selected_text.to_uppercase();
+                let new_text = if selected_text == upper_case {
+                    selected_text.to_lowercase()
+                } else {
+                    upper_case
+                };
+                text.delete_char_range(selected_chars.clone());
+                text.insert_text(&new_text, selected_chars.start);
+            }
+        }
+
+        ui.horizontal(|ui| {
+            ui.label("Move cursor to the:");
+
+            if ui.button("start").clicked() {
+                let text_edit_id = output.response.id;
+                if let Some(mut state) = egui::TextEdit::load_state(ui.ctx(), text_edit_id) {
+                    let ccursor = egui::text::CCursor::new(0);
+                    state.set_ccursor_range(Some(egui::text::CCursorRange::one(ccursor)));
+                    state.store(ui.ctx(), text_edit_id);
+                    ui.ctx().memory().request_focus(text_edit_id); // give focus back to the [`TextEdit`].
+                }
+            }
+
+            if ui.button("end").clicked() {
+                let text_edit_id = output.response.id;
+                if let Some(mut state) = egui::TextEdit::load_state(ui.ctx(), text_edit_id) {
+                    let ccursor = egui::text::CCursor::new(text.chars().count());
+                    state.set_ccursor_range(Some(egui::text::CCursorRange::one(ccursor)));
+                    state.store(ui.ctx(), text_edit_id);
+                    ui.ctx().memory().request_focus(text_edit_id); // give focus back to the [`TextEdit`].
+                }
+            }
+        });
+    }
+}