xpdftree.cc

这是一个做pdf阅读器的源代码文件,是大家学习阅读器资料的很好参考

  }
  if (request->request_mode & CWHeight) {
    w->core.height = request->height;
  }
  if (request->request_mode & CWBorderWidth) {
    w->core.border_width = request->border_width;
  }

  // calculate the new ideal size
  parentReq.width = 0;
  parentReq.height = 0;
  if (cls->treeClass.calcSize) {
    (*cls->treeClass.calcSize)((Widget)w, widget,
			       &parentReq.width, &reply->height);
  } else {
    calcSize((Widget)w, widget, &parentReq.width, &reply->height);
  }

  // send geometry request to our parent
  parentReq.request_mode = CWWidth | CWHeight;
  if (request->request_mode & XtCWQueryOnly) {
    parentReq.request_mode |= XtCWQueryOnly;
  }
  result = XtMakeGeometryRequest((Widget)w, &parentReq, NULL);
  if (result == XtGeometryAlmost) {
    result = XtGeometryNo;
  }

  if (result == XtGeometryNo || (request->request_mode & XtCWQueryOnly)) {
    // restore the original geometry
    w->core.width = curWidth;
    w->core.height = curHeight;
    w->core.border_width = curBW;
  } else {
    if (cls->treeClass.layout) {
      (*cls->treeClass.layout)((Widget)w, widget);
    } else {
      layout((Widget)w, widget);
    }
  }

  return result;
}

static void changeManaged(Widget widget) {
  Dimension width, height;
  XPDFTreeWidgetClass cls = (XPDFTreeWidgetClass)XtClass(widget);

  // compute the ideal size
  if (!XtIsRealized(widget)) {
    width = XtWidth(widget);
    height = XtHeight(widget);
  } else {
    width = 0;
    height = 0;
  }
  if (cls->treeClass.calcSize) {
    (*cls->treeClass.calcSize)(widget, NULL, &width, &height);
  } else {
    calcSize(widget, NULL, &width, &height);
  }

  // make resize request to parent -- keep asking until we get a yes
  // or no
  while (XtMakeResizeRequest(widget, width, height, &width, &height)
	 == XtGeometryAlmost) ;

  // relayout
  if (cls->treeClass.layout) {
    (*cls->treeClass.layout)(widget, NULL);
  } else {
    layout(widget, NULL);
  }

#if XmVERSION > 1
  // update keyboard traversal
  XmeNavigChangeManaged(widget);
#else
  _XmNavigChangeManaged(widget);
#endif
}

static void initConstraint(Widget requestWidget, Widget newWidget,
			   ArgList args, Cardinal *numArgs) {
  XPDFTreeWidget w = (XPDFTreeWidget)XtParent(newWidget);
  XPDFTreeConstraint c;

  c = XPDFTreeCPart(newWidget);
  c->e = (XPDFTreeEntry *)gmalloc(sizeof(XPDFTreeEntry));
  c->e->widget = newWidget;
  c->e->children = NULL;
  c->e->next = NULL;
  if (c->entryParent) {
    insertChildOnList(c->e, &XPDFTreeCPart(c->entryParent)->e->children);
  } else {
    insertChildOnList(c->e, &w->tree.root);
  }
}

static void destroyConstraint(Widget widget) {
  deleteSubtree(widget);
}

static void deleteSubtree(Widget widget) {
  XPDFTreeWidget w = (XPDFTreeWidget)XtParent(widget);
  XPDFTreeConstraint c;

  c = XPDFTreeCPart(widget);
  if (!c->e) {
    return;
  }
  while (c->e->children) {
    deleteSubtree(c->e->children->widget);
  }
  if (c->entryParent) {
    deleteChildFromList(c->e, &XPDFTreeCPart(c->entryParent)->e->children);
  } else {
    deleteChildFromList(c->e, &w->tree.root);
  }
  gfree(c->e);
  c->e = NULL;
}

static Boolean constraintSetValues(Widget oldWidget, Widget requestWidget,
				   Widget newWidget,
				   ArgList args, Cardinal *numArgs) {
  XPDFTreeWidget w = (XPDFTreeWidget)XtParent(newWidget);
  XPDFTreeWidgetClass cls = (XPDFTreeWidgetClass)XtClass((Widget)w);
  XPDFTreeConstraint oc, nc;
  Boolean relayout;
  Dimension width, height;

  if (!XtIsManaged(newWidget)) {
    return False;
  }
  oc = XPDFTreeCPart(oldWidget);
  nc = XPDFTreeCPart(newWidget);
  relayout = False;
  if (nc->entryParent != oc->entryParent ||
      nc->entryPosition != oc->entryPosition) {
    if (oc->entryParent) {
      deleteChildFromList(oc->e, &XPDFTreeCPart(oc->entryParent)->e->children);
    } else {
      deleteChildFromList(oc->e, &w->tree.root);
    }
    if (nc->entryParent) {
      insertChildOnList(nc->e, &XPDFTreeCPart(nc->entryParent)->e->children);
    } else {
      insertChildOnList(nc->e, &w->tree.root);
    }
    relayout = True;
  } else if (nc->entryExpanded != oc->entryExpanded) {
    relayout = True;
  }

  if (relayout) {

    // calculate a new ideal size (reset the widget size first so
    // calcSize will compute a new one)
    width = 0;
    height = 0;
    if (cls->treeClass.calcSize) {
      (*cls->treeClass.calcSize)((Widget)w, NULL, &width, &height);
    } else {
      calcSize((Widget)w, NULL, &width, &height);
    }

    // make resize request to parent -- keep asking until we get a yes
    // or no
    while (XtMakeResizeRequest((Widget)w, width, height, &width, &height)
	   == XtGeometryAlmost) ;

    // relayout the widget
    if (cls->treeClass.layout) {
      (*cls->treeClass.layout)((Widget)w, NULL);
    } else {
      layout((Widget)w, NULL);
    }
  }

  return relayout;
}

static void insertChildOnList(XPDFTreeEntry *e, XPDFTreeEntry **listHead) {
  int pos;
  XPDFTreeEntry *e2;

  pos = XPDFTreeCPart(e->widget)->entryPosition;
  if (!*listHead || pos < XPDFTreeCPart((*listHead)->widget)->entryPosition) {
    e->next = *listHead;
    *listHead = e;
  } else {
    for (e2 = *listHead;
	 e2->next && pos >= XPDFTreeCPart(e2->next->widget)->entryPosition;
	 e2 = e2->next) ;
    e->next = e2->next;
    e2->next = e;
  }
}

static void deleteChildFromList(XPDFTreeEntry *e, XPDFTreeEntry **listHead) {
  XPDFTreeEntry **p;

  for (p = listHead; *p; p = &(*p)->next) {
    if (*p == e) {
      *p = e->next;
      e->next = NULL;
      return;
    }
  }
}

static void createGC(Widget widget) {
  XPDFTreeWidget w = (XPDFTreeWidget)widget;
  XGCValues gcValues;

  gcValues.foreground = w->manager.foreground;
  gcValues.line_width = 0;
  gcValues.line_style = LineSolid;
  w->tree.plainGC = XtGetGC(widget,
			    GCForeground | GCLineWidth | GCLineStyle,
			    &gcValues);

  gcValues.line_style = LineOnOffDash;
  gcValues.dashes = 1;
  gcValues.dash_offset = 0;
  w->tree.dottedGC = XtGetGC(widget,
			     GCForeground | GCLineWidth | GCLineStyle |
			         GCDashList | GCDashOffset,
			     &gcValues);
}

static void destroyGC(Widget widget) {
  XPDFTreeWidget w = (XPDFTreeWidget)widget;

  XtReleaseGC(widget, w->tree.plainGC);
  XtReleaseGC(widget, w->tree.dottedGC);
}

static void layout(Widget widget, Widget instigator) {
  XPDFTreeWidget w = (XPDFTreeWidget)widget;
  XPDFTreeEntry *e;
  Position x, y;

  x = w->tree.marginWidth + xpdfTreeIndent;
  y = w->tree.marginHeight;
  for (e = w->tree.root; e; e = e->next) {
    y = layoutSubtree(w, instigator, e, x, y, True);
  }
}

static int layoutSubtree(XPDFTreeWidget w, Widget instigator,
			 XPDFTreeEntry *e, Position x, Position y,
			 Boolean visible) {
  Widget ew;
  XPDFTreeEntry *child;
  XPDFTreeConstraint c;

  ew = e->widget;
  if (!XtIsManaged(ew)) {
    return y;
  }
  c = XPDFTreeCPart(ew);

  // place this entry
  if (ew) {
    if (visible) {
      if (ew == instigator) {
	ew->core.x = x;
	ew->core.y = y;
      } else {
#if XmVERSION > 1
	XmeConfigureObject(ew, x, y, ew->core.width, ew->core.height,
			   ew->core.border_width);
#else
	_XmConfigureObject(ew, x, y, ew->core.width, ew->core.height,
			   ew->core.border_width);
#endif
      }
      y += ew->core.height + 2 * ew->core.border_width;
    }
  }

  // place this entry's children
  x += xpdfTreeIndent;
  for (child = e->children; child; child = child->next) {
    y = layoutSubtree(w, instigator, child, x, y,
		      visible && (!c || c->entryExpanded));
  }

  return y;
}

static void calcSize(Widget widget, Widget instigator,
		     Dimension *totalWidth,
		     Dimension *totalHeight) {
  XPDFTreeWidget w = (XPDFTreeWidget)widget;
  XPDFTreeEntry *e;
  Dimension w1, h1, w2, h2;

  w1 = h1 = 0;
  for (e = w->tree.root; e; e = e->next) {
    calcSubtreeSize(w, instigator, e, &w2, &h2);
    if (w2 > w1) {
      w1 = w2;
    }
    h1 += h2;
  }
  w1 += xpdfTreeIndent + 2 * w->tree.marginWidth;
  h1 += 2 * w->tree.marginHeight;
  if (h1 == 0) {
    h1 = 1;
  }
  if (!*totalWidth) {
    *totalWidth = w1;
  }
  if (!*totalHeight) {
    *totalHeight = h1;
  }
}

static void calcSubtreeSize(XPDFTreeWidget w, Widget instigator,
			    XPDFTreeEntry *e,
			    Dimension *width, Dimension *height) {
  Widget ew;
  XPDFTreeEntry *child;
  XPDFTreeConstraint c;
  XtWidgetGeometry geom;
  Dimension w1, h1, w2, h2;
  
  ew = e->widget;
  if (!XtIsManaged(ew)) {
    *width = *height = 0;
    return;
  }
  c = XPDFTreeCPart(ew);

  // get size of this entry
  if (ew) {
    if (!XtIsManaged(ew)) {
      *width = *height = 0;
      return;
    }
    if (ew == instigator) {
      w1 = ew->core.width;
      h1 = ew->core.height;
    } else {
      XtQueryGeometry(ew, NULL, &geom);
      w1 = (geom.request_mode & CWWidth) ? geom.width : ew->core.width;
      h1 = (geom.request_mode & CWHeight) ? geom.height : ew->core.height;
    }
    h1 += 2 * ew->core.border_width;
  } else {
    // root of tree
    w1 = 0;
    h1 = 0;
  }

  // if this entry is expanded, get size of all of its children
  if (c->entryExpanded) {
    for (child = e->children; child; child = child->next) {
      calcSubtreeSize(w, instigator, child, &w2, &h2);
      w2 += xpdfTreeIndent;
      if (w2 > w1) {
	w1 = w2;
      }
      h1 += h2;
    }
  }

  *width = w1;
  *height = h1;
}

static Boolean needRelayout(Widget oldWidget, Widget newWidget) {
  XPDFTreeWidget ow = (XPDFTreeWidget)oldWidget;
  XPDFTreeWidget nw = (XPDFTreeWidget)newWidget;

  if (nw->tree.marginWidth != ow->tree.marginWidth ||
      nw->tree.marginHeight != ow->tree.marginHeight) {
    return True;
  }
  return False;
}

static void click(Widget widget, XEvent *event,
		  String *params, Cardinal *numParams) {
  XPDFTreeWidget w = (XPDFTreeWidget)widget;
  XButtonPressedEvent *bpe;
  XPDFTreeEntry *e;
  Boolean onExpandIcon;
  XPDFTreeConstraint c;
  XPDFTreeSelectCallbackStruct cbs;

  if (event->type != ButtonPress) {
    return;
  }
  bpe = (XButtonPressedEvent *)event;
  if (findPosition(w, bpe->x, bpe->y, &e, &onExpandIcon)) {
    if (onExpandIcon) {
      c = XPDFTreeCPart(e->widget);
      w->tree.redrawY = e->widget->core.y;
      XtVaSetValues(e->widget, XPDFNentryExpanded, !c->entryExpanded, NULL);
    } else {
      XmProcessTraversal(e->widget, XmTRAVERSE_CURRENT);
      XtCallActionProc(widget, "ManagerGadgetActivate", event, NULL, 0);
      cbs.reason = XmCR_ACTIVATE;
      cbs.event = event;
      cbs.selectedItem = e->widget;
      XtCallCallbackList(widget, w->tree.selectCallback, &cbs);
    }
  }
}

static Boolean findPosition(XPDFTreeWidget w, int x, int y,
			    XPDFTreeEntry **e, Boolean *onExpandIcon) {
  XPDFTreeEntry *e2;

  for (e2 = w->tree.root; e2; e2 = e2->next) {
    *e = e2;
    if (findPositionInSubtree(w, x, y, e, onExpandIcon)) {
      return True;
    }
  }
  return False;
}

// If (x,y) falls on either an expand/collapse icon or a label gadget,
// set *<e> and *<onExpandIcon> and return true.
static Boolean findPositionInSubtree(XPDFTreeWidget w, int x, int y,
				     XPDFTreeEntry **e,
				     Boolean *onExpandIcon) {
  Widget child;
  XPDFTreeConstraint c;
  XPDFTreeEntry *e2;
  int y1;

  child = (*e)->widget;
  y1 = child->core.y + child->core.height / 2;
  if (x >= child->core.x && x < child->core.x + child->core.width &&
      y >= child->core.y && y < child->core.y + child->core.height) {
    *onExpandIcon = False;
    return True;
  } else if (x >= child->core.x - 16 && x < child->core.x - 4 &&
	     y >= y1 - 6 && y < y1 + 6 &&
	     (*e)->children) {
    *onExpandIcon = True;
    return True;
  }
  c = XPDFTreeCPart(child);
  if (!c || c->entryExpanded) {
    for (e2 = (*e)->children; e2; e2 = e2->next) {
      *e = e2;
      if (findPositionInSubtree(w, x, y, e, onExpandIcon)) {
	return True;
      }
    }
  }
  return False;
}

Widget XPDFCreateTree(Widget parent, char *name,
		      ArgList argList, Cardinal numArgs) {
  return XtCreateWidget(name, xpdfTreeWidgetClass, parent, argList, numArgs);
}