MemoryViewWidget: Refactor. Remove OnItemChanged signal and QSignalBlocker - replace with a signal that is only sent at the correct time.

Source/Core/DolphinQt/Debugger/MemoryViewWidget.cpp

@@ -10,10 +10,11 @@
 #include <QClipboard>
 #include <QHBoxLayout>
 #include <QHeaderView>
+#include <QLineEdit>
 #include <QMenu>
 #include <QMouseEvent>
 #include <QScrollBar>
-#include <QSignalBlocker>
+#include <QStyledItemDelegate>
 #include <QTableWidget>
 #include <QtGlobal>
 
@@ -52,6 +53,14 @@ constexpr int SCROLLBAR_CENTER = SCROLLBAR_MAXIMUM / 2;
 
 const QString INVALID_MEMORY = QStringLiteral("-");
 
+void TableEditDelegate::setModelData(QWidget* editor, QAbstractItemModel* model,
+                                     const QModelIndex& index) const
+{
+  // Triggers on placing data into a cell. Editor has the text to be input, index has the location.
+  const QString input = qobject_cast<QLineEdit*>(editor)->text();
+  emit editFinished(index.row(), index.column(), input);
+}
+
 class MemoryViewTable final : public QTableWidget
 {
 public:
@@ -66,6 +75,11 @@ public:
     setSelectionMode(NoSelection);
     setTextElideMode(Qt::TextElideMode::ElideNone);
 
+    // Route user's direct cell inputs to an editFinished signal. Much better than an itemChanged
+    // signal and QSignalBlock juggling.
+    TableEditDelegate* table_edit_delegate = new TableEditDelegate(this);
+    setItemDelegate(table_edit_delegate);
+
     // Prevent colors from changing based on focus.
     QPalette palette(m_view->palette());
     palette.setBrush(QPalette::Inactive, QPalette::Highlight, palette.brush(QPalette::Highlight));
@@ -78,7 +92,8 @@ public:
 
     connect(this, &MemoryViewTable::customContextMenuRequested, m_view,
             &MemoryViewWidget::OnContextMenu);
-    connect(this, &MemoryViewTable::itemChanged, this, &MemoryViewTable::OnItemChanged);
+    connect(table_edit_delegate, &TableEditDelegate::editFinished, this,
+            &MemoryViewTable::OnDirectTableEdit);
   }
 
   void resizeEvent(QResizeEvent* event) override
@@ -146,9 +161,9 @@ public:
     }
   }
 
-  void OnItemChanged(QTableWidgetItem* item)
+  void OnDirectTableEdit(const int row, const int column, const QString& text)
   {
-    QString text = item->text();
+    QTableWidgetItem* item = this->item(row, column);
     MemoryViewWidget::Type type =
         static_cast<MemoryViewWidget::Type>(item->data(USER_ROLE_VALUE_TYPE).toInt());
     std::vector<u8> bytes = m_view->ConvertTextToBytes(type, text);
@@ -156,16 +171,16 @@ public:
     u32 address = item->data(USER_ROLE_CELL_ADDRESS).toUInt();
     u32 end_address = address + static_cast<u32>(bytes.size()) - 1;
     AddressSpace::Accessors* accessors = AddressSpace::GetAccessors(m_view->GetAddressSpace());
-
-    const Core::CPUThreadGuard guard(m_view->m_system);
-
-    if (!bytes.empty() && accessors->IsValidAddress(guard, address) &&
-        accessors->IsValidAddress(guard, end_address))
     {
-      for (const u8 c : bytes)
+      const Core::CPUThreadGuard guard(m_view->m_system);
-        accessors->WriteU8(guard, address++, c);
-    }
 
+      if (!bytes.empty() && accessors->IsValidAddress(guard, address) &&
+          accessors->IsValidAddress(guard, end_address))
+      {
+        for (const u8 c : bytes)
+          accessors->WriteU8(guard, address++, c);
+      }
+    }
     m_view->Update();
   }
 
@@ -292,8 +307,6 @@ void MemoryViewWidget::CreateTable()
   m_table->verticalHeader()->setMinimumSectionSize(m_font_vspace);
   m_table->horizontalHeader()->setMinimumSectionSize(m_font_width * 2);
 
-  const QSignalBlocker blocker(m_table);
-
   // Set column and row parameters.
   // Span is the number of unique memory values covered in one row.
   const int data_span = m_bytes_per_row / GetTypeSize(m_type);
@@ -398,7 +411,6 @@ void MemoryViewWidget::Update()
   if (m_table->item(1, 1) == nullptr)
     return;
 
-  const QSignalBlocker blocker(m_table);
   m_table->clearSelection();
 
   // Update addresses
@@ -464,8 +476,6 @@ void MemoryViewWidget::UpdateColumns(const Core::CPUThreadGuard* guard)
   if (m_table->item(1, 1) == nullptr)
     return;
 
-  const QSignalBlocker blocker(m_table);
-
   for (int i = 0; i < m_table->rowCount(); i++)
   {
     for (int c = 0; c < m_data_columns; c++)

Source/Core/DolphinQt/Debugger/MemoryViewWidget.h

@@ -3,6 +3,7 @@
 
 #pragma once
 
+#include <QStyledItemDelegate>
 #include <QWidget>
 
 #include "Common/CommonTypes.h"
@@ -22,6 +23,21 @@ class CPUThreadGuard;
 class System;
 }  // namespace Core
 
+// Captures direct editing of the table.
+class TableEditDelegate : public QStyledItemDelegate
+{
+  Q_OBJECT
+
+public:
+  explicit TableEditDelegate(QObject* parent) : QStyledItemDelegate(parent) {}
+
+  void setModelData(QWidget* editor, QAbstractItemModel* model,
+                    const QModelIndex& index) const override;
+
+signals:
+  void editFinished(const int row, const int column, const QString& text) const;
+};
+
 class MemoryViewTable;
 
 class MemoryViewWidget final : public QWidget