* gui/conversation.h (OutputTextArea): Now inherit from

	QTextEditor, for the nth time.
	(OutputTextArea::sizeHint): Declare as override.
	* gui/conversation.cc (OutputTextArea::OutputTextArea): Make the
	output text editor read only.  Disallow vertical scroll bars.
	(OutputTextArea::sizeHint): Give a tight estimate.
	(OutputTextArea::add_paragraph): Tidy.
	(OutputTextArea::add_text): Likewise.
	(Exchange::reply_to_query): Toggle the mouse in busy state
	after submitting query.
	(Conversation::read_reply): Untoggle mouse' busy state if last
	output text was read.

3 files changed, 44 insertions, 7 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index b1ec2b77..dc33a80c 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,18 @@
+2011-07-01  Gabriel Dos Reis  <gdr@cs.tamu.edu>
+
+	* gui/conversation.h (OutputTextArea): Now inherit from
+	QTextEditor, for the nth time.
+	(OutputTextArea::sizeHint): Declare as override.
+	* gui/conversation.cc (OutputTextArea::OutputTextArea): Make the
+	output text editor read only.  Disallow vertical scroll bars.
+	(OutputTextArea::sizeHint): Give a tight estimate.
+	(OutputTextArea::add_paragraph): Tidy.
+	(OutputTextArea::add_text): Likewise.
+	(Exchange::reply_to_query): Toggle the mouse in busy state
+	after submitting query.
+	(Conversation::read_reply): Untoggle mouse' busy state if last
+	output text was read.
+
 2011-06-30  Gabriel Dos Reis  <gdr@cs.tamu.edu>
 
 	* sman/sman.c (main): Don't start Hyperdoc if no X11 server is running.
diff --git a/src/gui/conversation.cc b/src/gui/conversation.cc
index 0293b494..c3357e0f 100644
--- a/src/gui/conversation.cc
+++ b/src/gui/conversation.cc
@@ -35,6 +35,7 @@
 #include <iostream>
 
 #include <QScrollBar>
+#include <QApplication>
 #include "conversation.h"
 #include "debate.h"
 
@@ -64,11 +65,27 @@ namespace OpenAxiom {
    // --------------------
    OutputTextArea::OutputTextArea(QWidget* p)
          : Base(p) {
+      setReadOnly(true);          // this is a output only area.
+      setLineWrapMode(NoWrap);    // for the time being, mess with nothing.
       setFont(p->font());
+      setViewportMargins(0, 0, 0, 0);
       setSizePolicy(QSizePolicy::Preferred, QSizePolicy::MinimumExpanding);
+      // We do not want to see scroll bars.  Usually disallowing vertical
+      // scroll bars and allocating enough horizontal space is sufficient
+      // to ensure that we don't see any horizontal scrollbar.
+      setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
       setLineWidth(1);
    }
 
+   // This overriding implementation is so that we can control the
+   // amount of vertical space in the read-only editor viewport allocated
+   // for the display of output text.  In particular we do not want
+   // scrollbars.
+   QSize
+   OutputTextArea::sizeHint() const {
+      return QSize(width(), document()->lineCount() * fontMetrics().height());
+   }
+
    // Concatenate two paragraphs.
    static QString
    accumulate_paragaphs(const QString& before, const QString& after) {
@@ -78,7 +95,7 @@ namespace OpenAxiom {
    }
    
    void OutputTextArea::add_paragraph(const QString& s) {
-      setText(accumulate_paragaphs(text(), s));
+      setPlainText(accumulate_paragaphs(toPlainText(), s));
       QSize sz = sizeHint();
       sz.setWidth(parentWidget()->width() - our_margin(this));
       resize(sz);
@@ -87,7 +104,7 @@ namespace OpenAxiom {
    }
 
    void OutputTextArea::add_text(const QString& s) {
-      setText(text() + s);
+      setPlainText(toPlainText() + s);
       QSize sz = sizeHint();
       const int w = parentWidget()->width() - 2 * frameWidth();
       if (w > sz.width())
@@ -228,6 +245,7 @@ namespace OpenAxiom {
       if (empty_string(input))
          return;
       topic()->submit_query(input);
+      QApplication::setOverrideCursor(QCursor(Qt::WaitCursor));
    }
 
    void Exchange::resizeEvent(QResizeEvent* e) {
@@ -393,8 +411,10 @@ namespace OpenAxiom {
          exchange()->updateGeometry();
          if (empty_string(output.prompt))
             ensure_visibility(debate(), exchange());
-         else
+         else {
             ensure_visibility(debate(), next(exchange()));
+            QApplication::restoreOverrideCursor();
+	 }
       }
    }
 
diff --git a/src/gui/conversation.h b/src/gui/conversation.h
index 85220122..8f379f8d 100644
--- a/src/gui/conversation.h
+++ b/src/gui/conversation.h
@@ -35,7 +35,7 @@
 #include <vector>
 #include <QFrame>
 #include <QLineEdit>
-#include <QLabel>
+#include <QTextEdit>
 #include <QFont>
 #include <QEvent>
 #include <QResizeEvent>
@@ -57,10 +57,12 @@ namespace OpenAxiom {
    // --------------------
    // An output text area is a widget where we output text.
    // The texts are accumulated, as opposed to overwritten.
-   class OutputTextArea : public QLabel {
-      typedef QLabel Base;
+   class OutputTextArea : public QTextEdit {
+      typedef QTextEdit Base;
    public:
       explicit OutputTextArea(QWidget*);
+      // the metrics of this output area
+      QSize sizeHint() const;
       // Add a new paragraph to existing texts.  Paragraghs are
       // separated by the newline character.
       void add_paragraph(const QString&);
@@ -123,7 +125,7 @@ namespace OpenAxiom {
       // Conversion number
       int number() const { return no; }
 
-      // Reimplement positiion management.
+      // Reimplement position management.
       QSize sizeHint() const;
 
    protected: