LibGUI: Add a simple emoji input dialog activated by Ctrl+Alt+Space :^)

Widgets can now opt in to emoji input via set_accepts_emoji_input().
If the focused widget accepts emoji input, we'll pop up a simple dialog
with all the available emojis as clickable buttons.

You can press escape if you change your mind and don't want an emoji.

This UI layout definitely will not scale as we add more emojis, but it
works for the moment, and we can adapt it as we go. Pretty cool! :^)

Libraries/LibGUI/CMakeLists.txt

@@ -21,6 +21,7 @@ set(SOURCES
     Dialog.cpp
     DisplayLink.cpp
     DragOperation.cpp
+    EmojiInputDialog.cpp
     Event.cpp
     FilePicker.cpp
     FileSystemModel.cpp

Libraries/LibGUI/EmojiInputDialog.cpp

@@ -0,0 +1,110 @@
+/*
+ * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <AK/FileSystemPath.h>
+#include <AK/StringBuilder.h>
+#include <AK/Utf32View.h>
+#include <LibCore/DirIterator.h>
+#include <LibGUI/BoxLayout.h>
+#include <LibGUI/Button.h>
+#include <LibGUI/EmojiInputDialog.h>
+#include <LibGUI/Event.h>
+#include <LibGUI/Frame.h>
+#include <stdlib.h>
+
+namespace GUI {
+
+static Vector<u32> supported_emoji_codepoints()
+{
+    Vector<u32> codepoints;
+    Core::DirIterator dt("/res/emoji", Core::DirIterator::SkipDots);
+    while (dt.has_next()) {
+        auto filename = dt.next_path();
+        auto fspath = FileSystemPath(filename);
+        if (fspath.extension() != "png")
+            continue;
+        auto basename = fspath.basename();
+        if (!basename.starts_with("U+"))
+            continue;
+        u32 codepoint = strtoul(basename.characters() + 2, nullptr, 16);
+        codepoints.append(codepoint);
+    }
+    return codepoints;
+}
+
+EmojiInputDialog::EmojiInputDialog(Window* parent_window)
+    : Dialog(parent_window)
+{
+    set_frameless(true);
+
+    auto& main_widget = set_main_widget<Frame>();
+    main_widget.set_frame_shape(Gfx::FrameShape::Container);
+    main_widget.set_frame_shadow(Gfx::FrameShadow::Raised);
+    main_widget.set_fill_with_background_color(true);
+    auto& main_layout = main_widget.set_layout<VerticalBoxLayout>();
+    main_layout.set_spacing(0);
+
+    auto codepoints = supported_emoji_codepoints();
+
+    size_t index = 0;
+    size_t columns = 5;
+    size_t rows = ceil_div(codepoints.size(), columns);
+
+    for (size_t row = 0; row < rows && index < codepoints.size(); ++row) {
+        auto& horizontal_container = main_widget.add<Widget>();
+        auto& horizontal_layout = horizontal_container.set_layout<HorizontalBoxLayout>();
+        horizontal_layout.set_spacing(0);
+        for (size_t column = 0; column < columns; ++column) {
+            StringBuilder builder;
+            builder.append(Utf32View(&codepoints[index++], 1));
+            auto emoji_text = builder.to_string();
+            auto& button = horizontal_container.add<Button>(emoji_text);
+            button.set_button_style(Gfx::ButtonStyle::CoolBar);
+            button.on_click = [this, button = &button](auto) {
+                m_selected_emoji_text = button->text();
+                done(ExecOK);
+            };
+            if (index >= codepoints.size()) {
+                horizontal_layout.add_spacer();
+                break;
+            }
+        }
+    }
+}
+
+void EmojiInputDialog::event(Core::Event& event)
+{
+    if (event.type() == Event::KeyDown) {
+        auto& key_event = static_cast<KeyEvent&>(event);
+        if (key_event.key() == Key_Escape) {
+            done(ExecCancel);
+            return;
+        }
+    }
+    Dialog::event(event);
+}
+
+}

Libraries/LibGUI/EmojiInputDialog.h

@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#pragma once
+
+#include <LibGUI/Dialog.h>
+
+namespace GUI {
+
+class EmojiInputDialog final : public Dialog {
+    C_OBJECT(EmojiInputDialog);
+
+public:
+    const String& selected_emoji_text() const { return m_selected_emoji_text; }
+
+private:
+    virtual void event(Core::Event&) override;
+    explicit EmojiInputDialog(Window* parent_window);
+
+    String m_selected_emoji_text;
+};
+
+}

Libraries/LibGUI/Widget.h

@@ -272,6 +272,9 @@ public:
 
     Gfx::Rect content_rect() const;
 
+    void set_accepts_emoji_input(bool b) { m_accepts_emoji_input = b; }
+    bool accepts_emoji_input() const { return m_accepts_emoji_input; }
+
 protected:
     Widget();
 
@@ -337,6 +340,7 @@ private:
     bool m_greedy_for_hits { false };
     bool m_enabled { true };
     bool m_updates_enabled { true };
+    bool m_accepts_emoji_input { false };
 
     NonnullRefPtr<Gfx::PaletteImpl> m_palette;
 };

Libraries/LibGUI/WindowServerConnection.cpp

@@ -33,6 +33,7 @@
 #include <LibGUI/Desktop.h>
 #include <LibGUI/DisplayLink.h>
 #include <LibGUI/DragOperation.h>
+#include <LibGUI/EmojiInputDialog.h>
 #include <LibGUI/Event.h>
 #include <LibGUI/Menu.h>
 #include <LibGUI/Widget.h>
@@ -167,6 +168,17 @@ void WindowServerConnection::handle(const Messages::WindowClient::KeyDown& messa
         action->activate();
         return;
     }
+
+    bool focused_widget_accepts_emoji_input = window->focused_widget() && window->focused_widget()->accepts_emoji_input();
+    if (focused_widget_accepts_emoji_input && (message.modifiers() == (Mod_Ctrl | Mod_Alt)) && message.key() == Key_Space) {
+        auto emoji_input_dialog = EmojiInputDialog::construct(window);
+        if (emoji_input_dialog->exec() != EmojiInputDialog::ExecOK)
+            return;
+        key_event->m_key = Key_Invalid;
+        key_event->m_modifiers = 0;
+        key_event->m_text = emoji_input_dialog->selected_emoji_text();
+    }
+
     Core::EventLoop::current().post_event(*window, move(key_event));
 }