Item delegates: refactor and unify code

We had code duplication all over the place between QItemDelegate
and QStyledItemDelegate. Refactor that code in QAbstractItemDelegatePrivate,
so that both can use it and we'll have one place to fix instead of two.

Change-Id: I0c5decdfac7b0dc6e001c8c970491080f7b2e75f
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
Reviewed-by: David Faure <david.faure@kdab.com>

1 files changed, 117 insertions, 1 deletions

diff --git a/src/widgets/itemviews/qabstractitemdelegate.cpp b/src/widgets/itemviews/qabstractitemdelegate.cpp
index 4dffa6efe7..4d0840c3d6 100644
--- a/src/widgets/itemviews/qabstractitemdelegate.cpp
+++ b/src/widgets/itemviews/qabstractitemdelegate.cpp
@@ -42,7 +42,17 @@
 #include <qevent.h>
 #include <qstring.h>
 #include <qdebug.h>
+#include <qlineedit.h>
+#include <qtextedit.h>
+#include <qplaintextedit.h>
+#include <qapplication.h>
 #include <private/qtextengine_p.h>
+#include <private/qabstractitemdelegate_p.h>
+
+#include <qpa/qplatformintegration.h>
+#include <qpa/qplatformdrag.h>
+#include <private/qguiapplication_p.h>
+#include <private/qdnd_p.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -165,7 +175,7 @@ QT_BEGIN_NAMESPACE
     Creates a new abstract item delegate with the given \a parent.
 */
 QAbstractItemDelegate::QAbstractItemDelegate(QObject *parent)
-    : QObject(parent)
+    : QObject(*new QAbstractItemDelegatePrivate, parent)
 {
 
 }
@@ -405,6 +415,112 @@ QVector<int> QAbstractItemDelegate::paintingRoles() const
     return QVector<int>();
 }
 
+QAbstractItemDelegatePrivate::QAbstractItemDelegatePrivate()
+    : QObjectPrivate()
+{
+}
+
+bool QAbstractItemDelegatePrivate::editorEventFilter(QObject *object, QEvent *event)
+{
+    Q_Q(QAbstractItemDelegate);
+
+    QWidget *editor = qobject_cast<QWidget*>(object);
+    if (!editor)
+        return false;
+    if (event->type() == QEvent::KeyPress) {
+        switch (static_cast<QKeyEvent *>(event)->key()) {
+        case Qt::Key_Tab:
+            if (tryFixup(editor)) {
+                emit q->commitData(editor);
+                emit q->closeEditor(editor, QAbstractItemDelegate::EditNextItem);
+            }
+            return true;
+        case Qt::Key_Backtab:
+            if (tryFixup(editor)) {
+                emit q->commitData(editor);
+                emit q->closeEditor(editor, QAbstractItemDelegate::EditPreviousItem);
+            }
+            return true;
+        case Qt::Key_Enter:
+        case Qt::Key_Return:
+#ifndef QT_NO_TEXTEDIT
+            if (qobject_cast<QTextEdit *>(editor) || qobject_cast<QPlainTextEdit *>(editor))
+                return false; // don't filter enter key events for QTextEdit or QPlainTextEdit
+#endif // QT_NO_TEXTEDIT
+            // We want the editor to be able to process the key press
+            // before committing the data (e.g. so it can do
+            // validation/fixup of the input).
+            if (!tryFixup(editor))
+                return true;
+
+            QMetaObject::invokeMethod(q, "_q_commitDataAndCloseEditor",
+                                      Qt::QueuedConnection, Q_ARG(QWidget*, editor));
+            return false;
+        case Qt::Key_Escape:
+            // don't commit data
+            emit q->closeEditor(editor, QAbstractItemDelegate::RevertModelCache);
+            return true;
+        default:
+            return false;
+        }
+    } else if (event->type() == QEvent::FocusOut || (event->type() == QEvent::Hide && editor->isWindow())) {
+        //the Hide event will take care of he editors that are in fact complete dialogs
+        if (!editor->isActiveWindow() || (QApplication::focusWidget() != editor)) {
+            QWidget *w = QApplication::focusWidget();
+            while (w) { // don't worry about focus changes internally in the editor
+                if (w == editor)
+                    return false;
+                w = w->parentWidget();
+            }
+#ifndef QT_NO_DRAGANDDROP
+            // The window may lose focus during an drag operation.
+            // i.e when dragging involves the taskbar on Windows.
+            QPlatformDrag *platformDrag = QGuiApplicationPrivate::instance()->platformIntegration()->drag();
+            if (platformDrag && platformDrag->currentDrag()) {
+                return false;
+            }
+#endif
+            if (tryFixup(editor))
+                emit q->commitData(editor);
+
+            emit q->closeEditor(editor, QAbstractItemDelegate::NoHint);
+        }
+    } else if (event->type() == QEvent::ShortcutOverride) {
+        if (static_cast<QKeyEvent*>(event)->key() == Qt::Key_Escape) {
+            event->accept();
+            return true;
+        }
+    }
+    return false;
+}
+
+bool QAbstractItemDelegatePrivate::tryFixup(QWidget *editor)
+{
+#ifndef QT_NO_LINEEDIT
+    if (QLineEdit *e = qobject_cast<QLineEdit*>(editor)) {
+        if (!e->hasAcceptableInput()) {
+            if (const QValidator *validator = e->validator()) {
+                QString text = e->text();
+                validator->fixup(text);
+                e->setText(text);
+            }
+            return e->hasAcceptableInput();
+        }
+    }
+#endif // QT_NO_LINEEDIT
+
+    return true;
+}
+
+void QAbstractItemDelegatePrivate::_q_commitDataAndCloseEditor(QWidget *editor)
+{
+    Q_Q(QAbstractItemDelegate);
+    emit q->commitData(editor);
+    emit q->closeEditor(editor, QAbstractItemDelegate::SubmitModelCache);
+}
+
 QT_END_NAMESPACE
 
+#include "moc_qabstractitemdelegate.cpp"
+
 #endif // QT_NO_ITEMVIEWS