iOS plugin: Add native font dialog

[ChangeLog][iOS] Added native font dialog support for iOS.

Task-number: QTBUG-109059
Change-Id: If38e990e1c5e9fc1a303fce3e79c09c2d45daaa0
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>

4 files changed, 237 insertions, 0 deletions

diff --git a/src/plugins/platforms/ios/CMakeLists.txt b/src/plugins/platforms/ios/CMakeLists.txt
index a52a1a8695..e768898574 100644
--- a/src/plugins/platforms/ios/CMakeLists.txt
+++ b/src/plugins/platforms/ios/CMakeLists.txt
@@ -60,6 +60,7 @@ qt_internal_extend_target(QIOSIntegrationPlugin CONDITION NOT TVOS
         qiosdocumentpickercontroller.h qiosdocumentpickercontroller.mm
         qiosfiledialog.h qiosfiledialog.mm
         qioscolordialog.h qioscolordialog.mm
+        qiosfontdialog.h qiosfontdialog.mm
         qiosmenu.h qiosmenu.mm
         qiosmessagedialog.h qiosmessagedialog.mm
         qiostextinputoverlay.h qiostextinputoverlay.mm
diff --git a/src/plugins/platforms/ios/qiosfontdialog.h b/src/plugins/platforms/ios/qiosfontdialog.h
new file mode 100644
index 0000000000..f0a92d0d6f
--- /dev/null
+++ b/src/plugins/platforms/ios/qiosfontdialog.h
@@ -0,0 +1,41 @@
+// Copyright (C) 2022 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
+
+#ifndef QIOSFONTDIALOG_H
+#define QIOSFONTDIALOG_H
+
+#include <QtCore/qeventloop.h>
+#include <qpa/qplatformdialoghelper.h>
+
+@interface QIOSFontDialogController : UIFontPickerViewController <UIFontPickerViewControllerDelegate,
+                                                                    UIAdaptivePresentationControllerDelegate>
+@end
+
+QT_BEGIN_NAMESPACE
+
+class QIOSFontDialog : public QPlatformFontDialogHelper
+{
+public:
+    QIOSFontDialog();
+    ~QIOSFontDialog();
+
+    void exec() override;
+
+    bool show(Qt::WindowFlags windowFlags, Qt::WindowModality windowModality, QWindow *parent) override;
+    void hide() override;
+
+    void setCurrentFont(const QFont &) override;
+    QFont currentFont() const override;
+
+    void updateCurrentFont(const QFont &);
+
+private:
+    QEventLoop m_eventLoop;
+    QIOSFontDialogController *m_viewController;
+    QFont m_currentFont;
+
+};
+
+QT_END_NAMESPACE
+
+#endif // QIOSFONTDIALOG_H
diff --git a/src/plugins/platforms/ios/qiosfontdialog.mm b/src/plugins/platforms/ios/qiosfontdialog.mm
new file mode 100644
index 0000000000..bf2be3e127
--- /dev/null
+++ b/src/plugins/platforms/ios/qiosfontdialog.mm
@@ -0,0 +1,190 @@
+// Copyright (C) 2022 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
+
+#import <UIKit/UIKit.h>
+
+#include <QtGui/qwindow.h>
+#include <QtGui/qfontdatabase.h>
+#include <QDebug>
+
+#include <QtCore/private/qcore_mac_p.h>
+#include <QtGui/private/qfont_p.h>
+#include <QtGui/private/qfontengine_p.h>
+
+#include "qiosfontdialog.h"
+#include "qiosintegration.h"
+
+@implementation QIOSFontDialogController {
+    QIOSFontDialog *m_fontDialog;
+}
+
+- (instancetype)initWithQIOSFontDialog:(QIOSFontDialog *)dialog
+{
+    UIFontPickerViewControllerConfiguration *configuration = [[UIFontPickerViewControllerConfiguration alloc] init];
+    if (dialog->options()->testOption(QFontDialogOptions::MonospacedFonts)) {
+        UIFontDescriptorSymbolicTraits traits;
+        traits |= UIFontDescriptorTraitMonoSpace;
+        configuration.filteredTraits = traits;
+    }
+    configuration.includeFaces = YES;
+    if (self = [super initWithConfiguration:configuration]) {
+        m_fontDialog = dialog;
+        self.delegate = self;
+        self.presentationController.delegate = self;
+    }
+    [configuration release];
+    return self;
+}
+
+- (void)setQFont:(const QFont &)font
+{
+    QFontInfo fontInfo(font);
+    auto family = fontInfo.family().toNSString();
+    auto size = fontInfo.pointSize();
+
+    NSDictionary *dictionary = @{
+        static_cast<NSString *>(UIFontDescriptorFamilyAttribute): family,
+        static_cast<NSString *>(UIFontDescriptorSizeAttribute): [NSNumber numberWithInt:size]
+    };
+    UIFontDescriptor *fd = [UIFontDescriptor fontDescriptorWithFontAttributes:dictionary];
+
+    UIFontDescriptorSymbolicTraits traits = 0;
+    if (font.style() == QFont::StyleItalic)
+        traits |= UIFontDescriptorTraitItalic;
+    if (font.weight() == QFont::Bold)
+        traits |= UIFontDescriptorTraitBold;
+    fd = [fd fontDescriptorWithSymbolicTraits:traits];
+
+    self.selectedFontDescriptor = fd;
+}
+
+- (void)updateQFont
+{
+    UIFontDescriptor *font = self.selectedFontDescriptor;
+    if (!font)
+        return;
+
+    NSDictionary *attributes = font.fontAttributes;
+    UIFontDescriptorSymbolicTraits traits = font.symbolicTraits;
+
+    QFont newFont;
+    int size = qRound(font.pointSize);
+    QString family = QString::fromNSString([attributes objectForKey:UIFontDescriptorFamilyAttribute]);
+    if (family.isEmpty()) {
+        // If includeFaces is true, then the font descriptor won't
+        // have the UIFontDescriptorFamilyAttribute key set so we
+        // need to create a UIFont to get the font family
+        UIFont *f = [UIFont fontWithDescriptor:font size:size];
+        family = QString::fromNSString(f.familyName);
+    }
+
+    QString style;
+    if ((traits & (UIFontDescriptorTraitItalic | UIFontDescriptorTraitBold)) == (UIFontDescriptorTraitItalic | UIFontDescriptorTraitBold))
+        style = "Bold Italic";
+    else if (traits & UIFontDescriptorTraitItalic)
+        style = "Italic";
+    else if (traits & UIFontDescriptorTraitBold)
+        style = "Bold";
+
+    newFont = QFontDatabase::font(family, style, size);
+
+    if (m_fontDialog) {
+        m_fontDialog->updateCurrentFont(newFont);
+        emit m_fontDialog->currentFontChanged(newFont);
+    }
+}
+
+// ----------------------UIFontPickerViewControllerDelegate--------------------------
+- (void)fontPickerViewControllerDidPickFont:(UIFontPickerViewController *)viewController
+{
+    [self updateQFont];
+    emit m_fontDialog->accept();
+}
+
+- (void)fontPickerViewControllerDidCancel:(UIFontPickerViewController *)viewController
+{
+    Q_UNUSED(viewController);
+    emit m_fontDialog->reject();
+}
+
+// ----------------------UIAdaptivePresentationControllerDelegate--------------------------
+- (void)presentationControllerDidDismiss:(UIPresentationController *)presentationController
+{
+    Q_UNUSED(presentationController);
+    emit m_fontDialog->reject();
+}
+
+@end
+
+QIOSFontDialog::QIOSFontDialog()
+    : m_viewController(nullptr)
+{
+}
+
+QIOSFontDialog::~QIOSFontDialog()
+{
+    hide();
+}
+
+void QIOSFontDialog::exec()
+{
+    m_eventLoop.exec(QEventLoop::DialogExec);
+}
+
+bool QIOSFontDialog::show(Qt::WindowFlags windowFlags, Qt::WindowModality windowModality, QWindow *parent)
+{
+    Q_UNUSED(windowFlags);
+    Q_UNUSED(windowModality);
+
+    if (!m_viewController) {
+        m_viewController = [[QIOSFontDialogController alloc] initWithQIOSFontDialog:this];
+        [m_viewController setQFont:m_currentFont];
+    }
+
+    if (windowModality == Qt::ApplicationModal || windowModality == Qt::WindowModal)
+        m_viewController.modalInPresentation = YES;
+
+    UIWindow *window = parent ? reinterpret_cast<UIView *>(parent->winId()).window
+        : qt_apple_sharedApplication().keyWindow;
+    if (!window)
+        return false;
+
+    // We can't present from view controller if already presenting
+    if (window.rootViewController.presentedViewController)
+        return false;
+
+    [window.rootViewController presentViewController:m_viewController animated:YES completion:nil];
+
+    return true;
+}
+
+void QIOSFontDialog::hide()
+{
+    [m_viewController dismissViewControllerAnimated:YES completion:nil];
+    [m_viewController release];
+    m_viewController = nullptr;
+    if (m_eventLoop.isRunning())
+        m_eventLoop.exit();
+}
+
+void QIOSFontDialog::setCurrentFont(const QFont &font)
+{
+    if (m_currentFont == font)
+        return;
+
+    m_currentFont = font;
+    if (m_viewController)
+        [m_viewController setQFont:font];
+}
+
+QFont QIOSFontDialog::currentFont() const
+{
+    return m_currentFont;
+}
+
+void QIOSFontDialog::updateCurrentFont(const QFont &font)
+{
+    m_currentFont = font;
+}
+
+
diff --git a/src/plugins/platforms/ios/qiostheme.mm b/src/plugins/platforms/ios/qiostheme.mm
index 5da1c68147..2c40149813 100644
--- a/src/plugins/platforms/ios/qiostheme.mm
+++ b/src/plugins/platforms/ios/qiostheme.mm
@@ -22,6 +22,7 @@
 #include "qiosfiledialog.h"
 #include "qiosmessagedialog.h"
 #include "qioscolordialog.h"
+#include "qiosfontdialog.h"
 #endif
 
 QT_BEGIN_NAMESPACE
@@ -100,6 +101,7 @@ bool QIOSTheme::usePlatformNativeDialog(QPlatformTheme::DialogType type) const
     case FileDialog:
     case MessageDialog:
     case ColorDialog:
+    case FontDialog:
         return !qt_apple_isApplicationExtension();
     default:
         return false;
@@ -119,6 +121,9 @@ QPlatformDialogHelper *QIOSTheme::createPlatformDialogHelper(QPlatformTheme::Dia
     case ColorDialog:
         return new QIOSColorDialog();
         break;
+    case FontDialog:
+        return new QIOSFontDialog();
+        break;
 #endif
     default:
         return 0;