Fix nested calls of setCurrentIndex which caused breakage.

ProgramTableView::focus_address() calls QAbstractItemView::setCurrentIndex().
verticalScrollBar() value is updated as result of current row change.
This emits signal valueChanged which is connected to ProgramTableView::adjust_scroll_pos().
It checks if the limit of range covered by actual model and row to address offset
is reached. If the top or bottom 1/8 of range is reached then model
needs to be adjusted to cover continuation area. Model shift requires
update of the current row to stay on the same address even that row 0
address offset is changed.

This model shifting is required because range of scroll is only signed
integer and QTableView is even more limited in row count to work
reliably.

Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>

8 files changed, 50 insertions, 30 deletions

diff --git a/qtmips_gui/memorymodel.cpp b/qtmips_gui/memorymodel.cpp
index 597b88f..b88c5b7 100644
--- a/qtmips_gui/memorymodel.cpp
+++ b/qtmips_gui/memorymodel.cpp
@@ -199,11 +199,7 @@ void MemoryModel::check_for_updates() {
     update_all();
 }
 
-bool MemoryModel::adjustRowAndOffset(int &row, int optimal_row, std::uint32_t address) {
-    if (optimal_row < rowCount() / 8)
-        optimal_row = rowCount() / 8;
-    if (optimal_row >= rowCount() - rowCount() / 8)
-        optimal_row = rowCount() - rowCount() / 8;
+bool MemoryModel::adjustRowAndOffset(int &row, std::uint32_t address) {
     row = rowCount() / 2;
     address -= address % cellSizeBytes();
     std::uint32_t row_bytes = cells_per_row * cellSizeBytes();
diff --git a/qtmips_gui/memorymodel.h b/qtmips_gui/memorymodel.h
index 7d12f91..01b5310 100644
--- a/qtmips_gui/memorymodel.h
+++ b/qtmips_gui/memorymodel.h
@@ -59,7 +59,7 @@ public:
     QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const override;
     Qt::ItemFlags flags(const QModelIndex &index) const;
     bool setData(const QModelIndex & index, const QVariant & value, int role);
-    bool adjustRowAndOffset(int &row, int optimal_row, std::uint32_t address);
+    bool adjustRowAndOffset(int &row, std::uint32_t address);
     void update_all();
 
     void setCellsPerRow(unsigned int cells);
diff --git a/qtmips_gui/memorytableview.cpp b/qtmips_gui/memorytableview.cpp
index aeec25e..74729c5 100644
--- a/qtmips_gui/memorytableview.cpp
+++ b/qtmips_gui/memorytableview.cpp
@@ -44,9 +44,12 @@
 
 MemoryTableView::MemoryTableView(QWidget *parent, QSettings *settings) : Super(parent) {
     connect(verticalScrollBar() , SIGNAL(valueChanged(int)),
-            this, SLOT(adjust_scroll_pos()));
+            this, SLOT(adjust_scroll_pos_check()));
+    connect(this , SIGNAL(adjust_scroll_pos_queue()),
+            this, SLOT(adjust_scroll_pos_process()), Qt::QueuedConnection);
     this->settings = settings;
     initial_address = settings->value("DataViewAddr0", 0).toULongLong();
+    adjust_scroll_pos_in_progress = false;
 }
 
 void MemoryTableView::addr0_save_change(std::uint32_t val) {
@@ -106,13 +109,21 @@ void MemoryTableView::set_cell_size(int index) {
     }
     adjustColumnCount();
     if (keep_row0) {
-        m->adjustRowAndOffset(row, m->rowCount() / 2, address);
+        m->adjustRowAndOffset(row, address);
         scrollTo(m->index(row, 0),
                  QAbstractItemView::PositionAtTop);
     }
 }
 
-void MemoryTableView:: adjust_scroll_pos() {
+void MemoryTableView::adjust_scroll_pos_check() {
+    if (!adjust_scroll_pos_in_progress) {
+        adjust_scroll_pos_in_progress = true;
+        emit adjust_scroll_pos_queue();
+    }
+}
+
+void MemoryTableView::adjust_scroll_pos_process() {
+    adjust_scroll_pos_in_progress = false;
     std::uint32_t address;
     MemoryModel *m = dynamic_cast<MemoryModel*>(model());
     if (m == nullptr)
@@ -127,16 +138,16 @@ void MemoryTableView:: adjust_scroll_pos() {
         int prev_row = row;
         if (row < m->rowCount() / 8) {
             if ((row == 0) && (index0_offset < row_bytes) && (index0_offset != 0)) {
-                m->adjustRowAndOffset(row, 0, 0);
+                m->adjustRowAndOffset(row, 0);
             } else if (index0_offset > row_bytes) {
                 m->get_row_address(address, row);
-                m->adjustRowAndOffset(row, m->rowCount() / 7, address);
+                m->adjustRowAndOffset(row, address);
             } else {
                 break;
             }
         } else if (row > m->rowCount() - m->rowCount() / 8) {
             m->get_row_address(address, row);
-            m->adjustRowAndOffset(row, m->rowCount() - m->rowCount() / 7, address);
+            m->adjustRowAndOffset(row, address);
         } else {
             break;
         }
@@ -175,7 +186,7 @@ void MemoryTableView::go_to_address(std::uint32_t address) {
     int row;
     if (m == nullptr)
         return;
-    m->adjustRowAndOffset(row, m->rowCount() / 2, address);
+    m->adjustRowAndOffset(row, address);
     scrollTo(m->index(row, 0),
          QAbstractItemView::PositionAtTop);
     setCurrentIndex(m->index(row, 1));
diff --git a/qtmips_gui/memorytableview.h b/qtmips_gui/memorytableview.h
index f2ed9cb..a84b80e 100644
--- a/qtmips_gui/memorytableview.h
+++ b/qtmips_gui/memorytableview.h
@@ -53,20 +53,23 @@ public:
     void resizeEvent(QResizeEvent *event) override;
 signals:
     void address_changed(std::uint32_t address);
+    void adjust_scroll_pos_queue();
 public slots:
     void set_cell_size(int index);
     void go_to_address(std::uint32_t address);
     void focus_address(std::uint32_t address);
 protected:
-     void keyPressEvent(QKeyEvent *event);
+    void keyPressEvent(QKeyEvent *event);
 private slots:
-    void adjust_scroll_pos();
+    void adjust_scroll_pos_check();
+    void adjust_scroll_pos_process();
 private:
     void addr0_save_change(std::uint32_t val);
     void adjustColumnCount();
     QSettings *settings;
 
     std::uint32_t initial_address;
+    bool adjust_scroll_pos_in_progress;
 };
 
 #endif // MEMORYTABLEVIEW_H
diff --git a/qtmips_gui/programmodel.cpp b/qtmips_gui/programmodel.cpp
index 76473a8..838c058 100644
--- a/qtmips_gui/programmodel.cpp
+++ b/qtmips_gui/programmodel.cpp
@@ -167,11 +167,7 @@ void ProgramModel::check_for_updates() {
     update_all();
 }
 
-bool ProgramModel::adjustRowAndOffset(int &row, int optimal_row, std::uint32_t address) {
-    if (optimal_row < rowCount() / 8)
-        optimal_row = rowCount() / 8;
-    if (optimal_row >= rowCount() - rowCount() / 8)
-        optimal_row = rowCount() - rowCount() / 8;
+bool ProgramModel::adjustRowAndOffset(int &row, std::uint32_t address) {
     row = rowCount() / 2;
     address -= address % cellSizeBytes();
     std::uint32_t row_bytes = cellSizeBytes();
diff --git a/qtmips_gui/programmodel.h b/qtmips_gui/programmodel.h
index 9beecef..f5159af 100644
--- a/qtmips_gui/programmodel.h
+++ b/qtmips_gui/programmodel.h
@@ -53,7 +53,7 @@ public:
     QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const override;
     Qt::ItemFlags flags(const QModelIndex &index) const;
     bool setData(const QModelIndex & index, const QVariant & value, int role);
-    bool adjustRowAndOffset(int &row, int optimal_row, std::uint32_t address);
+    bool adjustRowAndOffset(int &row, std::uint32_t address);
     void update_all();
 
     inline const QFont *getFont() const {
diff --git a/qtmips_gui/programtableview.cpp b/qtmips_gui/programtableview.cpp
index e3114a6..a684692 100644
--- a/qtmips_gui/programtableview.cpp
+++ b/qtmips_gui/programtableview.cpp
@@ -44,9 +44,12 @@
 
 ProgramTableView::ProgramTableView(QWidget *parent, QSettings *settings) : Super(parent) {
     connect(verticalScrollBar() , SIGNAL(valueChanged(int)),
-            this, SLOT(adjust_scroll_pos()));
+            this, SLOT(adjust_scroll_pos_check()));
+    connect(this , SIGNAL(adjust_scroll_pos_queue()),
+            this, SLOT(adjust_scroll_pos_process()), Qt::QueuedConnection);
     this->settings = settings;
     initial_address = settings->value("ProgramViewAddr0", 0).toULongLong();
+    adjust_scroll_pos_in_progress = false;
 }
 
 void ProgramTableView::addr0_save_change(std::uint32_t val) {
@@ -85,7 +88,15 @@ void ProgramTableView::adjustColumnCount() {
     }
 }
 
-void ProgramTableView:: adjust_scroll_pos() {
+void ProgramTableView::adjust_scroll_pos_check() {
+    if (!adjust_scroll_pos_in_progress) {
+        adjust_scroll_pos_in_progress = true;
+        emit adjust_scroll_pos_queue();
+    }
+}
+
+void ProgramTableView::adjust_scroll_pos_process() {
+    adjust_scroll_pos_in_progress = false;
     std::uint32_t address;
     ProgramModel *m = dynamic_cast<ProgramModel*>(model());
     if (m == nullptr)
@@ -100,16 +111,16 @@ void ProgramTableView:: adjust_scroll_pos() {
         int prev_row = row;
         if (row < m->rowCount() / 8) {
             if ((row == 0) && (index0_offset < row_bytes) && (index0_offset != 0)) {
-                m->adjustRowAndOffset(row, 0, 0);
-            } else if (index0_offset > row_bytes) {
+                m->adjustRowAndOffset(row, 0);
+            } else if (index0_offset >= row_bytes) {
                 m->get_row_address(address, row);
-                m->adjustRowAndOffset(row, m->rowCount() / 7, address);
+                m->adjustRowAndOffset(row, address);
             } else {
                 break;
             }
         } else if (row > m->rowCount() - m->rowCount() / 8) {
             m->get_row_address(address, row);
-            m->adjustRowAndOffset(row, m->rowCount() - m->rowCount() / 7, address);
+            m->adjustRowAndOffset(row, address);
         } else {
             break;
         }
@@ -148,7 +159,7 @@ void ProgramTableView:: go_to_address(std::uint32_t address) {
     int row;
     if (m == nullptr)
         return;
-    m->adjustRowAndOffset(row, m->rowCount() / 2, address);
+    m->adjustRowAndOffset(row, address);
     scrollTo(m->index(row, 0),
          QAbstractItemView::PositionAtTop);
     setCurrentIndex(m->index(row, 1));
diff --git a/qtmips_gui/programtableview.h b/qtmips_gui/programtableview.h
index 5a67f51..6298d89 100644
--- a/qtmips_gui/programtableview.h
+++ b/qtmips_gui/programtableview.h
@@ -53,19 +53,22 @@ public:
     void resizeEvent(QResizeEvent *event) override;
 signals:
     void address_changed(std::uint32_t address);
+    void adjust_scroll_pos_queue();
 public slots:
     void go_to_address(std::uint32_t address);
     void focus_address(std::uint32_t address);
 protected:
-     void keyPressEvent(QKeyEvent *event);
+    void keyPressEvent(QKeyEvent *event);
 private slots:
-    void adjust_scroll_pos();
+    void adjust_scroll_pos_check();
+    void adjust_scroll_pos_process();
 private:
     void addr0_save_change(std::uint32_t val);
     void adjustColumnCount();
     QSettings *settings;
 
     std::uint32_t initial_address;
+    bool adjust_scroll_pos_in_progress;
 };
 
 #endif // PROGRAMTABLEVIEW_H