From 9247ac654e2ac8044f173813cdbb6d7e310897c1 Mon Sep 17 00:00:00 2001
From: ronso0 <ronso0@mixxx.org>
Date: Fri, 24 Nov 2023 15:21:46 +0100
Subject: [PATCH] MIDI Input editor: allow selecting multiple Options

---
 .../delegates/midioptionsdelegate.cpp         | 73 ++++++++++++++-----
 .../delegates/midioptionsdelegate.h           |  3 +
 2 files changed, 58 insertions(+), 18 deletions(-)

diff --git a/src/controllers/delegates/midioptionsdelegate.cpp b/src/controllers/delegates/midioptionsdelegate.cpp
index deab2ea10c04..198cf06c0bbc 100644
--- a/src/controllers/delegates/midioptionsdelegate.cpp
+++ b/src/controllers/delegates/midioptionsdelegate.cpp
@@ -1,10 +1,12 @@
 #include "controllers/delegates/midioptionsdelegate.h"
 
 #include <QComboBox>
+#include <QStandardItemModel>
 
 #include "controllers/midi/midimessage.h"
 #include "controllers/midi/midiutils.h"
 #include "moc_midioptionsdelegate.cpp"
+#include "util/parented_ptr.h"
 
 namespace {
 
@@ -41,12 +43,16 @@ QWidget* MidiOptionsDelegate::createEditor(QWidget* parent,
                                            const QModelIndex& index) const {
     Q_UNUSED(option);
     Q_UNUSED(index);
-    QComboBox* pComboBox = new QComboBox(parent);
 
-    for (const MidiOption choice : kMidiOptions) {
-        pComboBox->addItem(MidiUtils::midiOptionToTranslatedString(choice),
-                static_cast<uint16_t>(choice));
-    }
+    // Create and connect the box. It'll be opulated in seteditorData().
+    QComboBox* pComboBox = make_parented<QComboBox>(parent);
+    // Clicking an option or pressing Enter on a selected option toggles it,
+    // closes the list view and commits the updated data.
+    // Press Space in list view only toggles the check state.
+    connect(pComboBox,
+            QOverload<int>::of(&QComboBox::activated),
+            this,
+            &MidiOptionsDelegate::commitAndCloseEditor);
 
     return pComboBox;
 }
@@ -66,28 +72,59 @@ QString MidiOptionsDelegate::displayText(const QVariant& value,
 
 void MidiOptionsDelegate::setEditorData(QWidget* editor,
                                         const QModelIndex& index) const {
-    MidiOptions options = index.data(Qt::EditRole).value<MidiOptions>();
-
-    QComboBox* pComboBox = qobject_cast<QComboBox*>(editor);
-    if (pComboBox == nullptr) {
+    auto* pComboBox = qobject_cast<QComboBox*>(editor);
+    if (!pComboBox) {
         return;
     }
-    for (int i = 0; i < pComboBox->count(); ++i) {
-        if (MidiOptions(pComboBox->itemData(i).toInt()) & options) {
-            pComboBox->setCurrentIndex(i);
-            return;
-        }
+
+    MidiOptions options = index.data(Qt::EditRole).value<MidiOptions>();
+    auto* pModel = static_cast<QStandardItemModel*>(pComboBox->model());
+    DEBUG_ASSERT(pModel);
+    for (const MidiOption opt : kMidiOptions) {
+        QStandardItem* pItem =
+                new QStandardItem(MidiUtils::midiOptionToTranslatedString(opt));
+        pItem->setData(static_cast<uint16_t>(opt));
+        pItem->setCheckable(true);
+        pItem->setCheckState(options.testFlag(opt) ? Qt::Checked : Qt::Unchecked);
+        pModel->appendRow(pItem);
     }
+
+    // Show popup immediately, don't require another click
+    pComboBox->showPopup();
 }
 
 void MidiOptionsDelegate::setModelData(QWidget* editor,
                                        QAbstractItemModel* model,
                                        const QModelIndex& index) const {
-    MidiOptions options;
-    QComboBox* pComboBox = qobject_cast<QComboBox*>(editor);
-    if (pComboBox == nullptr) {
+    // Collect checked options and write them back to the model
+    auto* pComboBox = qobject_cast<QComboBox*>(editor);
+    if (!pComboBox) {
         return;
     }
-    options = MidiOptions(pComboBox->itemData(pComboBox->currentIndex()).toInt());
+
+    auto* pModel = static_cast<QStandardItemModel*>(pComboBox->model());
+    DEBUG_ASSERT(pModel);
+    MidiOptions options;
+    for (int i = 0; i < pModel->rowCount(); i++) {
+        auto* pItem = pModel->item(i);
+        // Only check for Qt::Checked or else, ignore Qt::PartiallyChecked
+        options.setFlag(static_cast<MidiOption>(pItem->data().toUInt()),
+                pItem->checkState() == Qt::Checked);
+    }
     model->setData(index, QVariant::fromValue(options), Qt::EditRole);
 }
+
+void MidiOptionsDelegate::commitAndCloseEditor(int index) {
+    QComboBox* pComboBox = qobject_cast<QComboBox*>(sender());
+    if (!pComboBox) {
+        return;
+    }
+    auto* pModel = static_cast<QStandardItemModel*>(pComboBox->model());
+    DEBUG_ASSERT(pModel);
+    auto* pItem = pModel->item(index);
+    DEBUG_ASSERT(pItem);
+    pItem->setCheckState(pItem->checkState() == Qt::Checked ? Qt::Unchecked : Qt::Checked);
+
+    emit commitData(pComboBox);
+    emit closeEditor(pComboBox);
+}
diff --git a/src/controllers/delegates/midioptionsdelegate.h b/src/controllers/delegates/midioptionsdelegate.h
index f690df38f957..8d175eb0b2ee 100644
--- a/src/controllers/delegates/midioptionsdelegate.h
+++ b/src/controllers/delegates/midioptionsdelegate.h
@@ -17,4 +17,7 @@ class MidiOptionsDelegate : public QStyledItemDelegate {
 
     void setModelData(QWidget* editor, QAbstractItemModel* model,
                       const QModelIndex& index) const;
+
+  private slots:
+    void commitAndCloseEditor(int index);
 };