From 8190b05419a5b2058f7015d08e0653a2e8a4bc78 Mon Sep 17 00:00:00 2001
From: Vadim Zeitlin <vadim@wxwidgets.org>
Date: Tue, 7 Nov 2000 16:55:41 +0000
Subject: [PATCH] horz scrolling in etxt ctrl works better

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/wxUNIVERSAL@8704 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
---
 TODO                  | 11 ++++++++---
 samples/univ/univ.cpp |  4 ++--
 src/univ/textctrl.cpp | 46 ++++++++++++++++++++++++++++++++++++-------
 3 files changed, 49 insertions(+), 12 deletions(-)

diff --git a/TODO b/TODO
index 38e1a901a8..2194eeaf0b 100644
--- a/TODO
+++ b/TODO
@@ -1,3 +1,9 @@
+----------------------------------------------------------------------------
+TEST
+----------------------------------------------------------------------------
+
+    how Paste/Cut work with undo/redo in wxTextCtrl?
+
 ----------------------------------------------------------------------------
 TODO
 ----------------------------------------------------------------------------
@@ -8,12 +14,11 @@ samples:
 
 wxTextCtrl
 
-*   display corrupted when typing text in quickly (single line)
+*!  display corrupted when typing text in quickly (caret problem?)
+*   scrollbars don't disappear after deleting long line
 ?   text ctrl display pb when text is truncated
 *   too much is refreshed when double clicking (word select)
 
-!!  own ScrollWindow() for horz scrolling as we must always scroll by char!
-
 All
 
 !   wxThemeSettings
diff --git a/samples/univ/univ.cpp b/samples/univ/univ.cpp
index e00aa20cfa..3f6704cf29 100644
--- a/samples/univ/univ.cpp
+++ b/samples/univ/univ.cpp
@@ -389,8 +389,6 @@ MyUnivFrame::MyUnivFrame(const wxString& title)
 #if 0
     wxTextCtrl *text = new wxTextCtrl(this, -1, _T("Hello, Universe!"),
                                       wxPoint(10, 40));
-    text->SetFont(wxFont(24, wxFONTFAMILY_DEFAULT,
-                         wxFONTSTYLE_NORMAL, wxFONTWEIGHT_NORMAL));
     wxSize sizeText = text->GetBestSize();
     sizeText.x = 200;
     text->SetSize(sizeText);
@@ -408,6 +406,8 @@ MyUnivFrame::MyUnivFrame(const wxString& title)
     TestTextCtrlReplace(text, "first\nsecond\n\nthird line");
 #endif
 #endif
+    text->SetFont(wxFont(24, wxFONTFAMILY_DEFAULT,
+                         wxFONTSTYLE_NORMAL, wxFONTWEIGHT_NORMAL));
     text->SetFocus();
     //text->SetEditable(FALSE);
 #endif // !TEST_TEXT_ONLY/TEST_TEXT_ONLY
diff --git a/src/univ/textctrl.cpp b/src/univ/textctrl.cpp
index 3c51883d19..3f3148b5ba 100644
--- a/src/univ/textctrl.cpp
+++ b/src/univ/textctrl.cpp
@@ -1303,18 +1303,19 @@ void wxTextCtrl::ShowPosition(long pos)
             return;
         }
 
+        wxRect rectText = GetRealTextArea();
+
+        // scroll the position vertically into view: if it is currently above
+        // it, make it the first one, otherwise the last one
         if ( m_scrollRangeY )
         {
-            // scroll the position vertically into view: if it is currently
-            // above it, make it the first one, otherwise the last one
             if ( row < yStart )
             {
                 Scroll(0, row);
             }
-            else
+            else // we are currently in or below the view area
             {
-                int yEnd = yStart +
-                            GetRealTextArea().height / GetCharHeight() - 1;
+                int yEnd = yStart + rectText.height / GetCharHeight() - 1;
                 if ( yEnd < row )
                 {
                     // scroll down: the current item should appear at the
@@ -1324,9 +1325,34 @@ void wxTextCtrl::ShowPosition(long pos)
             }
         }
 
+        // scroll the position horizontally into view
         if ( m_scrollRangeX )
         {
-            // TODO
+            // unlike for the rows, xStart doesn't correspond to the starting
+            // column as they all have different widths, so we need to
+            // translate everything to pixels
+
+            // we want the text between posLeft and posRight be entirely inside
+            // the view (i.e. the current character)
+            wxString line = GetLineText(row);
+            wxCoord posLeft = GetTextWidth(line.Left(col));
+
+            // make xStart the first visible pixel (and not position)
+            int wChar = GetCharWidth();
+            xStart *= GetCharWidth();
+
+            if ( posLeft < xStart )
+            {
+                Scroll(posLeft / wChar, row);
+            }
+            else // maybe we're beyond the right border of the view?
+            {
+                wxCoord posRight = posLeft + GetTextWidth(line[(size_t)col]);
+                if ( posRight > xStart + rectText.width )
+                {
+                    Scroll(posRight / wChar, row);
+                }
+            }
         }
     }
     //else: multiline but no scrollbars, hence nothing to do
@@ -2502,11 +2528,17 @@ void wxTextCtrl::DoDrawTextInRect(wxDC& dc, const wxRect& rectUpdate)
 
             if ( colEnd > m_colLastVisible )
                 colEnd = m_colLastVisible;
+
+            // we don't draw the last character because it may be shown only
+            // partially in single line mode (in multi line we can't avoid
+            // showing parts of characters anyhow)
+            if ( colEnd > colStart )
+                colEnd--;
         }
 
         // extract the part of line we need to redraw
         wxString textLine = GetLineText(line);
-        wxString text = textLine.Mid(colStart, colEnd - colStart);
+        wxString text = textLine.Mid(colStart, colEnd - colStart + 1);
 
         // now deal with the selection
         int selStart, selEnd;