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>

1 files changed, 18 insertions, 7 deletions

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));