add basic TextInput class with support for minimal text editing

meson.build

@@ -37,6 +37,7 @@ raven_source_files = [
   './src/BoxLayout.cpp',
   './src/Label.cpp',
   './src/ListView.cpp',
+  './src/TextInput.cpp',
 ]
 
 raven_header_files = [

src/Events.hpp

@@ -1,5 +1,6 @@
 #pragma once
 
+#include <X11/X.h>
 #include <stdint.h>
 #include "Point.hpp"
 #include "Box.hpp"
@@ -15,6 +16,7 @@ enum class EventType {
     RepaintRect,
     FocusUpdate,
     ActivationUpdate,
+    Key
 };
 
 class Event {
@@ -27,6 +29,41 @@ public:
     virtual ~Event() = default;
 };
 
+class KeyEvent : public Event {
+public:
+    using RavenKeySym = KeySym;
+
+    enum class KeyStatus {
+        HasNone = 0,
+        HasKeySym,
+        HasKeyChars,
+        HasBoth
+    };
+
+    KeyEvent(RavenKeySym key_sym, std::string key_chars, KeyStatus status, bool control_pressed, bool shift_pressed)
+        : Event()
+        , m_key_sym(key_sym)
+        , m_key_chars(key_chars)
+        , m_status(status)
+        , m_control_pressed(control_pressed)
+        , m_shift_pressed(shift_pressed) {}
+
+    EventType type() { return EventType::Key; }
+    const char *name() { return "Key"; }
+
+    RavenKeySym key_sym() { return m_key_sym; }
+    std::string &key_chars() { return m_key_chars; }
+    KeyStatus status() { return m_status; }
+    bool control_pressed() { return m_control_pressed; }
+    bool shift_pressed() { return m_shift_pressed; }
+private:
+    RavenKeySym m_key_sym {};
+    std::string m_key_chars {};
+    KeyStatus m_status { KeyStatus::HasNone };
+    bool m_control_pressed { false };
+    bool m_shift_pressed { false };
+};
+
 class MouseButtonEvent : public Event {
 private:
     bool m_was_left_button_pressed;

src/Painter.cpp

@@ -4,6 +4,7 @@
 #include "pango/pango-layout.h"
 #include "pango/pango-types.h"
 #include "pango/pangocairo.h"
+#include "Box.hpp"
 
 namespace Raven {
 
@@ -49,7 +50,7 @@ Point Painter::compute_text_size(Box &widget_geometry, std::string &text, PangoF
     return { pango_units_to_double(font_width), pango_units_to_double(font_height) };
 }
 
-void Painter::text(Box &geometry, std::string &text, PaintTextAlign align, PangoEllipsizeMode ellipsize, PangoFontDescription *pango_font_description) {
+void Painter::text(Box &geometry, std::string &text, PaintTextAlign align, PangoEllipsizeMode ellipsize, PangoFontDescription *pango_font_description, int cursor_pos) {
     PangoLayout *layout = pango_cairo_create_layout(m_cairo->cobj());
 
     int font_width;
@@ -79,6 +80,19 @@ void Painter::text(Box &geometry, std::string &text, PaintTextAlign align, Pango
     }
     pango_cairo_show_layout(m_cairo->cobj(), layout);
 
+    if (cursor_pos >= 0) {
+        PangoRectangle pango_cursor_rect;
+        pango_layout_get_cursor_pos(layout, cursor_pos, &pango_cursor_rect, NULL);
+        Box cursor_rect = {
+            static_cast<double>(pango_units_to_double(pango_cursor_rect.x)),
+            pango_units_to_double(pango_cursor_rect.y) + y,
+            1.0,
+            static_cast<double>(pango_units_to_double(pango_cursor_rect.height))
+        };
+
+        m_cairo->rectangle(cursor_rect.x(), cursor_rect.y(), cursor_rect.width(), cursor_rect.height());
+    }
+
     g_object_unref(layout);
 }
 

src/Painter.hpp

@@ -25,7 +25,7 @@ public:
 
     void rounded_rectangle(Box &geometry, double border_radius);
     Point compute_text_size(Box &widget_geometry, std::string &text, PangoFontDescription *pango_font_description);
-    void text(Box &geometry, std::string &text, PaintTextAlign align, PangoEllipsizeMode ellipsize, PangoFontDescription *pango_font_description);
+    void text(Box &geometry, std::string &text, PaintTextAlign align, PangoEllipsizeMode ellipsize, PangoFontDescription *pango_font_description, int cursor_pos = -1);
 
     bool can_paint() { if (m_cairo) return true; else return false; }
 

src/Styles.cpp

@@ -124,4 +124,26 @@ GenericStyle flat_listview_style {
     false
 };
 
+GenericStyle flat_textinput_style {
+    pango_font_description_from_string("sans-serif"),
+    black1,
+    white2,
+    white2,
+    white1,
+    6.0,
+    true,
+    true
+};
+
+GenericStyle raised_textinput_style {
+    pango_font_description_from_string("sans-serif"),
+    black1,
+    white1,
+    white1,
+    white0,
+    6.0,
+    true,
+    true
+};
+
 }

src/Styles.hpp

@@ -33,5 +33,7 @@ extern GenericStyle accent_button_style;
 extern GenericStyle flat_label_style;
 extern GenericStyle flat_listview_style;
 extern GenericStyle raised_listview_style;
+extern GenericStyle flat_textinput_style;
+extern GenericStyle raised_textinput_style;
 
 }

src/TextInput.cpp

@@ -0,0 +1,132 @@
+#include "TextInput.hpp"
+#include "Events.hpp"
+#include "Logging.hpp"
+#include "Painter.hpp"
+#include "src/Styles.hpp"
+#include <cctype>
+#include <string>
+#include <locale>
+
+namespace Raven {
+
+void TextInput::set_text(std::string text) {
+    m_text = text;
+    m_cursor = m_text.length();
+
+    // We won't use the fit_text() function here, since reflowing is a little slower than repainting.
+    // It's better for text input to feel snappier, thus we will make the assumption that all text input
+    // widgets will not scale themselves to fit the text inside. We will rely on the parent layout or
+    // the user of the library explicitly sizing this widget.
+
+    repaint();
+}
+
+void TextInput::on_init() {
+    set_remains_active(true);
+    set_style_pure(&flat_textinput_style);
+
+    set_did_init(true);
+    if (!fit_text(m_text)) {
+        reflow();
+    }
+    m_cursor = m_text.length();
+} 
+
+void TextInput::on_paint() {
+    auto painter = window()->painter();
+    auto geometry = rect().max_geometry();
+
+    int displayed_cursor_pos = m_cursor;
+    if (!is_active()) {
+        displayed_cursor_pos = -1;
+    }
+
+    painter.source_rgb(style()->foreground());
+    painter.text(geometry, m_text, Raven::PaintTextAlign::Left, PANGO_ELLIPSIZE_END, style()->font_description(), displayed_cursor_pos);
+    painter.fill();
+}
+
+void TextInput::text_did_change() {
+    repaint();
+}
+
+void TextInput::insert(std::string chars) {
+    m_text.insert(m_cursor, chars);
+    m_cursor++;
+    text_did_change();
+}
+
+void TextInput::on_key(KeyEvent &event) {
+    INFO << "on_key: " << event.key_chars() << std::endl;
+    switch (event.status()) {
+        case KeyEvent::KeyStatus::HasKeyChars: {
+            insert(event.key_chars());
+            break;
+        }
+        case KeyEvent::KeyStatus::HasBoth: /* fallthrough */
+        case KeyEvent::KeyStatus::HasKeySym: {
+            auto key_sym = event.key_sym();
+
+            if (event.control_pressed()) {
+                switch (key_sym) {
+                    case XK_a: key_sym = XK_Home; break;
+                    case XK_e: key_sym = XK_End; break;
+                    case XK_f: key_sym = XK_Right; break;
+                    case XK_b: key_sym = XK_Left; break;
+                    default: {
+                        return;
+                    }
+                }
+            }
+            
+            switch (key_sym) {
+                default: {
+                    // FIXME
+                    if (!iscntrl((unsigned char)*event.key_chars().c_str())) {
+                        insert(event.key_chars());
+                    }
+                    break;
+                }
+                case XK_BackSpace: {
+                    if (!m_cursor) return;
+                    m_cursor--;
+                    m_text.erase(m_cursor, 1);
+                    text_did_change();
+                    break;
+                }
+                case XK_KP_Left:
+                case XK_Left: {
+                    m_cursor = std::max(m_cursor - 1, 0);
+                    text_did_change();
+                    break;
+                }
+                case XK_KP_Right:
+                case XK_Right: {
+                    m_cursor = std::min(m_cursor + 1, static_cast<int>(m_text.length()));
+                    text_did_change();
+                    break;
+                }
+                case XK_Home:
+	            case XK_KP_Home: {
+                    m_cursor = 0;
+                    text_did_change();
+                    break;
+                }
+                case XK_End:
+	            case XK_KP_End: {
+                    m_cursor = m_text.length();
+                    text_did_change();
+                    break;
+                }
+            }
+        }
+
+        case KeyEvent::KeyStatus::HasNone:
+        default: {
+            return;
+        }
+    }
+}
+
+
+}

src/TextInput.hpp

@@ -0,0 +1,26 @@
+#pragma once
+
+#include "Widget.hpp"
+
+namespace Raven {
+
+class TextInput : public Raven::Widget {
+public:
+    TextInput()
+        : Raven::Widget() {}
+
+    std::string &text() { return m_text; }
+    void set_text(std::string text);
+protected:
+    void on_init() override;
+    void on_paint() override;
+    void on_key(KeyEvent &event) override;
+private:
+    void insert(std::string chars);
+    void text_did_change();
+
+    std::string m_text {""};
+    int m_cursor { 0 };
+};
+
+}

src/Widget.cpp

@@ -244,17 +244,20 @@ void Widget::handle_mouse_move_event(MouseMoveEvent &event) {
 void Widget::handle_mouse_button_event(MouseButtonEvent &event) {
     bool update_activation_to = event.was_left_button_pressed();
 
+    if (!update_activation_to && m_remains_active) {
+        update_activation_to = true;
+    }
+
     if (!m_rect.contains(event.point())) {
         update_activation_to = false;
     }
 
     on_mouse_button(event);
 
-    if (m_is_active != update_activation_to) {
+    if (m_is_active != update_activation_to || (update_activation_to && m_window->active_widget() != this)) {
         m_is_active = update_activation_to;
         if (m_is_active && m_window)
             m_window->set_active_widget(this);
-
         auto activation_update_event = ActivationUpdateEvent(update_activation_to);
         on_activation_update(activation_update_event);
 
@@ -279,6 +282,10 @@ void Widget::handle_mouse_button_event(MouseButtonEvent &event) {
     }
 }
 
+void Widget::handle_key_event(KeyEvent &event) {
+    on_key(event);
+}
+
 void Widget::dispatch_event(Event &event) {
     if (!m_accepts_events || !m_did_init)
         return;
@@ -302,6 +309,10 @@ void Widget::dispatch_event(Event &event) {
             handle_relayout_subtree(reinterpret_cast<RelayoutSubtreeEvent&>(event));
             break;
         }
+        case EventType::Key: {
+            handle_key_event(reinterpret_cast<KeyEvent&>(event));
+            break;
+        }
         /* these events aren't handled here, as they won't be dispatched to us from other places */
         case EventType::FocusUpdate:
         case EventType::ActivationUpdate:

src/Widget.hpp

@@ -89,6 +89,9 @@ public:
     bool accepts_events() { return m_accepts_events; }
     void set_accepts_events(bool accepts_events) { m_accepts_events = accepts_events; }
 
+    bool remains_active() { return m_remains_active; }
+    void set_remains_active(bool remains_active) { m_remains_active = remains_active; }
+
     bool absolute() { return m_absolute; }
     void set_absolute(bool absolute) { m_absolute = absolute; } 
 
@@ -124,6 +127,7 @@ protected:
     virtual void on_paint() {}
     virtual void on_layout() {}
     virtual void on_after_layout() {}
+    virtual void on_key(KeyEvent &event) {}
 
     void set_did_init(bool did_init) { m_did_init = did_init; }
     Point compute_window_relative();
@@ -135,6 +139,7 @@ private:
     void handle_relayout_subtree(RelayoutSubtreeEvent &event);
     void handle_mouse_move_event(MouseMoveEvent &event);
     void handle_mouse_button_event(MouseButtonEvent &event);
+    void handle_key_event(KeyEvent &event);
 
     Point m_window_relative { 0, 0 };
     Box m_rect { 0, 0, 0, 0 };
@@ -150,6 +155,7 @@ private:
     bool m_accepts_events { true };
     bool m_absolute { false };
     bool m_grows { false };
+    bool m_remains_active { false };
     ControlWidgetType m_control_type { ControlWidgetType::Widget };
 };
 

src/Window.cpp

@@ -22,9 +22,8 @@ void Window::set_main_widget(std::shared_ptr<Widget> main_widget) {
 
 bool Window::spawn_window() {
     Display *dsp = XOpenDisplay(NULL);
-    XSynchronize(dsp, False);
     if (dsp == NULL) {
-        std::cerr << "error: XOpenDisplay(NULL)" << "\n";
+        std::cerr << "error: XOpenDisplay failed" << "\n";
         return false;
     }
     m_x_display = dsp;
@@ -46,6 +45,14 @@ bool Window::spawn_window() {
     );
 
     XSelectInput(dsp, da, ButtonPressMask | ButtonReleaseMask | KeyPressMask | PointerMotionMask | StructureNotifyMask | ExposureMask);
+
+	if ((m_xim = XOpenIM(dsp, NULL, NULL, NULL)) == NULL) {
+        std::cerr << "error: XOpenIM failed" << "\n";
+        return false;
+    }
+
+	m_xic = XCreateIC(m_xim, XNInputStyle, XIMPreeditNothing | XIMStatusNothing, XNClientWindow, da, XNFocusWindow, da, NULL);
+
     XMapWindow(dsp, da);
 
     m_xlib_surface = Cairo::XlibSurface::create(
@@ -214,6 +221,27 @@ void Window::run(bool block) {
                 auto point = Point(e.xmotion.x, e.xmotion.y);
                 auto event = MouseMoveEvent(point);
                 dispatch_to_main_widget(event);
+                break;
+            }
+            case KeyPress: {
+                if (m_active_widget) {
+                    KeySym keysym;
+                    char chars[32];
+                    Status status;
+
+                    XmbLookupString(m_xic, &e.xkey, chars, sizeof(chars), &keysym, &status);
+
+                    Raven::KeyEvent::KeyStatus key_status = Raven::KeyEvent::KeyStatus::HasNone;
+                    switch (status) {
+                        case XLookupChars: key_status = Raven::KeyEvent::KeyStatus::HasKeyChars; break;
+                        case XLookupKeySym: key_status = Raven::KeyEvent::KeyStatus::HasKeySym; break;
+                        case XLookupBoth: key_status = Raven::KeyEvent::KeyStatus::HasBoth; break;
+                        default: key_status = Raven::KeyEvent::KeyStatus::HasNone; break;
+                    }
+                    auto event = KeyEvent(keysym, chars, key_status, e.xkey.state & ControlMask, e.xkey.state & ShiftMask);
+                    m_active_widget->dispatch_event(event);
+                }
+                break;
             }
             default: {
                 break;

src/Window.hpp

@@ -66,6 +66,8 @@ private:
     std::queue<std::function<void()>> m_microtasks;
 
     Display *m_x_display { nullptr };
+    XIM m_xim { nullptr };
+    XIC m_xic { nullptr };
 
     bool dispatch_to_main_widget(Event &event);
 };

src/main.cpp

@@ -1,6 +1,7 @@
 #include "Label.hpp"
 #include "ColumnLayout.hpp"
 #include "ListView.hpp"
+#include "TextInput.hpp"
 #include "Window.hpp"
 #include "Widget.hpp"
 #include "Button.hpp"
@@ -40,16 +41,44 @@ int main() {
     auto selected_label = content->add<Raven::Label>("No selection");
     selected_label->rect().set_max_height(28.0);
 
-    auto next_button = content->add<Raven::Button>("Next Item", Raven::Button::Accent);
-    
-    auto delete_button = content->add<Raven::Button>("Delete Item");
-    delete_button->set_style(&Raven::raised_button_style);
+    auto control_row = content->add<Raven::Widget>();
+    control_row->set_style(&Raven::raised_widget_style);
+    control_row->rect().set_min_height(28.0);
+    auto control_row_layout = control_row->set_layout<Raven::BoxLayout>(Raven::Direction::Horizontal);
+    control_row_layout->set_spacing(6.0);
 
-    delete_button->on_click = [list_view, &window]() {
-        window.queue_microtask([list_view](){
-            list_view->elements.erase(list_view->elements.begin() + list_view->active_element());
-            list_view->set_active_element(list_view->active_element() - 1);
-        });
+    auto next_button = control_row->add<Raven::Button>("Next Item", Raven::Button::Accent);
+    next_button->set_grows(true);
+    
+    auto delete_button = control_row->add<Raven::Button>("Delete Item");
+    delete_button->set_style(&Raven::raised_button_style);
+    delete_button->set_grows(true);
+
+    content->add<Raven::Label>("Edit an item");
+
+    auto edit_row = content->add<Raven::Widget>();
+    edit_row->set_style(&Raven::raised_widget_style);
+    edit_row->rect().set_min_height(28.0);
+    auto edit_row_layout = edit_row->set_layout<Raven::BoxLayout>(Raven::Direction::Horizontal);
+    edit_row_layout->set_spacing(6.0);
+
+    auto edit_input = edit_row->add<Raven::TextInput>();
+    edit_input->set_style(&Raven::raised_textinput_style);
+    edit_input->set_grows(true);
+
+    auto edit_button = edit_row->add<Raven::Button>("Edit");
+    edit_button->set_style(&Raven::accent_button_style);
+
+    edit_button->on_click = [list_view, edit_input]() {
+        if (list_view->active_element() >= 0) {
+            list_view->elements[list_view->active_element()] = edit_input->text();
+            list_view->elements_updated();
+        }
+    };
+
+    delete_button->on_click = [list_view]() {
+        list_view->elements.erase(list_view->elements.begin() + list_view->active_element());
+        list_view->set_active_element(list_view->active_element() - 1);
     };
 
     next_button->on_click = [list_view]() {
@@ -57,7 +86,7 @@ int main() {
     };
 
     list_view->on_selection = [selected_label](unsigned int index, std::string item) {
-        selected_label->set_text("You have selected: " + item);
+        selected_label->set_text("Selected: " + item);
     };
 
     int i = 1000;