Implemented pageUp: and pageDown:

git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/gui/trunk@14709 72102866-910b-0410-8b05-ffd578937521

ChangeLog

@@ -1,3 +1,12 @@
+Thu Oct 10 19:56:29 2002  Nicola Pero  <n.pero@mi.flashnet.it>
+
+	* Source/NSScrollView.m ([-scrollPageUp:]): Implemented.
+	([-scrollPageDown:]): Implemented.  ([-pageUp:]):
+	Implemented. ([-pageDown:]): Implemented.  
+	* Source/NSTextView.m ([-pageDown:]): Implemented.
+	([-pageUp:]): Implemented.
+	(Patch by David Ayers <d.ayers@inode.at>).
+	
 Thu Oct 10 19:16:40 2002  Nicola Pero  <n.pero@mi.flashnet.it>
 
 	* Source/NSFontManager.m ([NSFontManager -fontMenu:]): Use 't'

Source/NSScrollView.m

@@ -344,7 +344,102 @@ static float scrollerWidth;
 	  [_vertRuler setNeedsDisplay: YES];
 	}
     }
+}
 
+/**
+ * Scrolls the receiver by simply invoking scrollPageUp:
+ */
+- (void) pageUp: (id)sender
+{
+  [self scrollPageUp: sender];
+}
+
+/*
+ * This code is based on _doScroll: and still may need some tuning. 
+ */
+- (void) scrollPageUp: (id)sender
+{
+  NSRect  clipViewBounds;
+  NSPoint point;
+  float   amount;
+
+  if (_contentView == nil)
+    {
+      clipViewBounds = NSZeroRect;
+    }
+  else
+    {
+      clipViewBounds = [_contentView bounds];
+    }
+  point = clipViewBounds.origin;
+  /*
+   * Take verticalPageScroll into accout, but try to make sure
+   * that amount is never negative (ie do not scroll backwards.)
+   *
+   * FIXME: It seems _doScroll and scrollWheel: should also take
+   * care not to do negative scrolling.
+   */
+  amount = clipViewBounds.size.height - _vPageScroll;
+  amount = (amount < 0) ? 0 : amount;
+
+  if (_contentView != nil && !_contentView->_rFlags.flipped_view)
+    {
+      amount = -amount;
+    }
+  point.y = clipViewBounds.origin.y - amount;
+  [_contentView scrollToPoint: point];
+  if (_rulersVisible == YES && _hasVertRuler == YES)
+    {
+      [_vertRuler setNeedsDisplay: YES];
+    }
+}
+
+/**
+ * Scrolls the receiver by simply invoking scrollPageUp:
+ */
+- (void) pageDown: (id)sender
+{
+  [self scrollPageDown: sender];
+}
+
+/*
+ * This code is based on _doScroll:. and still may need some tuning.
+ */
+- (void) scrollPageDown: (id)sender
+{
+  NSRect  clipViewBounds;
+  NSPoint point;
+  float   amount;
+
+  if (_contentView == nil)
+    {
+      clipViewBounds = NSZeroRect;
+    }
+  else
+    {
+      clipViewBounds = [_contentView bounds];
+    }
+  point = clipViewBounds.origin;
+  /*
+   * Take verticalPageScroll into accout, but try to make sure
+   * that amount is never negativ (ie do not scroll backwards.)
+   *
+   * FIXME: It seems _doScroll and scrollWheel: should also take
+   * care not to do negative scrolling.
+   */
+  amount = clipViewBounds.size.height - _vPageScroll;
+  amount = (amount < 0) ? 0 : amount;
+  if (_contentView != nil && !_contentView->_rFlags.flipped_view)
+    {
+      amount = -amount;
+    }
+  point.y = clipViewBounds.origin.y + amount;
+  [_contentView scrollToPoint: point];
+
+  if (_rulersVisible == YES && _hasVertRuler == YES)
+  {
+    [_vertRuler setNeedsDisplay: YES];
+  }
 }
 
 - (void) _doScroll: (NSScroller*)scroller

Source/NSTextView.m

@@ -3078,18 +3078,142 @@ afterString in order over charRange. */
   [self setSelectedRange: NSMakeRange (newLocation, 0) ];
 }
 
+/**
+ * Tries to move the selection/insertion point down one page of the
+ * visible rect in the receiver while trying to maintain the
+ * horizontal position of the last vertical movement.
+ * If the receiver is a field editor, this method returns immediatly. 
+ */
 - (void) pageDown: (id)sender
 {
-  // TODO
-  NSLog(@"Method %s is not implemented for class %s",
-	"pageDown:", "NSTextView");
+  float    cachedInsertPointX;
+  float    scrollDelta;
+  float    oldOriginY;
+  float    newOriginY;
+  unsigned glyphIDX;
+  unsigned charIDX;
+  NSPoint  iPoint;
+ 
+  if (_tf.is_field_editor)
+    return;
+  
+  /* 
+   * Save the current horizontal position cache as we will implictly
+   * change it later.
+   */
+  cachedInsertPointX = _originalInsertPoint;
+
+  /*
+   * Scroll; also determine how far to move the insertion point.
+   */
+  oldOriginY = NSMinY([self visibleRect]);
+  [[self enclosingScrollView] pageDown: sender];
+  newOriginY = NSMinY([self visibleRect]);
+  scrollDelta = newOriginY - oldOriginY;
+
+  if (scrollDelta == 0)
+    {
+      /* TODO/FIXME: If no scroll was done, it means we are in the
+       * last page of the document already - should we move the
+       * insertion point to the last line when the user clicks
+       * 'PageDown' in that case ?
+       */
+    }
+
+  /*
+   * Calculate new insertion point.
+   */
+  iPoint.x  = _originalInsertPoint        - _textContainerInset.width;
+  iPoint.y  = NSMidY(_insertionPointRect) - _textContainerInset.height;
+  iPoint.y += scrollDelta;
+
+  /*
+   * Ask the layout manager to compute where to go.
+   */
+  glyphIDX = [_layoutManager glyphIndexForPoint: iPoint
+                            inTextContainer: _textContainer];
+  charIDX  = [_layoutManager characterIndexForGlyphAtIndex: glyphIDX];
+
+  /*
+   * Move the insertion point (implicitly changing
+   * _originalInsertPoint).
+   */
+  [self setSelectedRange: NSMakeRange(charIDX, 0)];
+
+  /*
+   * Restore the _originalInsertPoint because we do not want it to
+   * change between moveUp:/moveDown:/pageUp:/pageDown: operations.  
+   */
+  _originalInsertPoint = cachedInsertPointX;
 }
 
+/**
+ * Tries to move the selection/insertion point up one page of the
+ * visible rect in the receiver while trying to maintain the
+ * horizontal position of the last vertical movement.
+ * If the receiver is a field editor, this method returns immediatly. 
+ */
 - (void) pageUp: (id)sender
 {
-  // TODO
-  NSLog(@"Method %s is not implemented for class %s",
-	"pageUp:", "NSTextView");
+  float    cachedInsertPointX;
+  float    scrollDelta;
+  float    oldOriginY;
+  float    newOriginY;
+  unsigned glyphIDX;
+  unsigned charIDX;
+  NSPoint  iPoint;
+
+  if (_tf.is_field_editor)
+    return;
+
+  /* 
+   * Save the current horizontal position cache as we will implictly
+   * change it later.
+   */
+  cachedInsertPointX = _originalInsertPoint;
+
+  /*
+   * Scroll; also determine how far to move the insertion point.
+   */
+  oldOriginY = NSMinY([self visibleRect]);
+  [[self enclosingScrollView] pageUp: sender];
+  newOriginY = NSMinY([self visibleRect]);
+  scrollDelta = newOriginY - oldOriginY;
+
+  if (scrollDelta == 0)
+    {
+      /* TODO/FIXME: If no scroll was done, it means we are in the
+       * first page of the document already - should we move the
+       * insertion point to the first line when the user clicks
+       * 'PageUp' in that case ?
+       */
+    }
+
+  /*
+   * Calculate new insertion point.
+   */
+  iPoint.x  = _originalInsertPoint        - _textContainerInset.width;
+  iPoint.y  = NSMidY(_insertionPointRect) - _textContainerInset.height;
+  iPoint.y += scrollDelta;
+
+  /*
+   * Ask the layout manager to compute where to go.
+   */
+  glyphIDX = [_layoutManager glyphIndexForPoint: iPoint
+                             inTextContainer: _textContainer];
+  charIDX  = [_layoutManager characterIndexForGlyphAtIndex: glyphIDX];
+
+  /*
+   * Move the insertion point (implicitly changing
+   * _originalInsertPoint). 
+   */
+  [self setSelectedRange: NSMakeRange(charIDX, 0)];
+  
+  /*
+   * Restore the _originalInsertPoint because we do not want it to
+   * change between moveUp:/moveDown:/pageUp:/pageDown: operations.
+   */
+  _originalInsertPoint = cachedInsertPointX;
 }
 
 - (void) scrollLineDown: (id)sender