HexdumpWidget: visible lines calculation

src/utils/Helpers.cpp

@@ -137,4 +137,15 @@ namespace qhelpers
         widget->setMaximumHeight(max);
     }
 
+
+    int getMaxFullyDisplayedLines(QPlainTextEdit *plainTextEdit)
+    {
+        QFontMetrics fontMetrics(plainTextEdit->document()->defaultFont());
+        return (plainTextEdit->height()
+                - (plainTextEdit->contentsMargins().top()
+                   + plainTextEdit->contentsMargins().bottom()
+                   + (int)(plainTextEdit->document()->documentMargin() * 2)))
+               / fontMetrics.lineSpacing();
+    }
+
 } // end namespace

src/utils/Helpers.h

@@ -40,6 +40,9 @@ namespace qhelpers
 
     SizePolicyMinMax forceWidth(QWidget *widget, int width);
     SizePolicyMinMax forceHeight(QWidget *widget, int height);
+
+
+    int getMaxFullyDisplayedLines(QPlainTextEdit *plainTextEdit);
 }
 
 #endif // HELPERS_H

src/widgets/DisassemblyWidget.cpp

@@ -3,6 +3,7 @@
 #include "utils/HexAsciiHighlighter.h"
 #include "utils/HexHighlighter.h"
 #include "utils/Configuration.h"
+#include "utils/Helpers.h"
 
 #include <QScrollBar>
 #include <QJsonArray>
@@ -186,12 +187,7 @@ void DisassemblyWidget::scrollInstructions(int count)
 
 void DisassemblyWidget::updateMaxLines()
 {
-    QFontMetrics fontMetrics(mDisasTextEdit->document()->defaultFont());
-    int currentMaxLines = (mDisasTextEdit->height() -
-                           (mDisasTextEdit->contentsMargins().top() + mDisasTextEdit->contentsMargins().bottom()
-                            + (int)(mDisasTextEdit->document()->documentMargin() * 2)))
-                          / fontMetrics.lineSpacing();
-
+    int currentMaxLines = qhelpers::getMaxFullyDisplayedLines(mDisasTextEdit);
     if (currentMaxLines != maxLines)
     {
         maxLines = currentMaxLines;

src/widgets/HexdumpWidget.cpp

@@ -184,6 +184,8 @@ void HexdumpWidget::refresh(RVA addr)
         addr = Core()->getOffset();
     }
 
+    updateVisibleLines(); // TODO: only on resize
+
     RCoreLocked lcore = Core()->core();
     // Prevent further scroll
     disconnect(ui->hexASCIIText->verticalScrollBar(), SIGNAL(valueChanged(int)), this, SLOT(hexScrolled()));
@@ -243,6 +245,12 @@ void HexdumpWidget::refresh(RVA addr)
 
 }
 
+
+void HexdumpWidget::updateVisibleLines()
+{
+    visibleLines = qhelpers::getMaxFullyDisplayedLines(ui->hexHexText);
+}
+
 /*
  * Content management functions
  */

src/widgets/HexdumpWidget.h

@@ -59,11 +59,15 @@ protected:
 private:
     std::unique_ptr<Ui::HexdumpWidget> ui;
 
+    int visibleLines;
+
     RVA topOffset;
     RVA bottomOffset;
 
     void refresh(RVA addr = RVA_INVALID);
 
+    void updateVisibleLines();
+
 private slots:
     void on_seekChanged(RVA addr);
     void raisePrioritizedMemoryWidget(CutterCore::MemoryWidgetType type);