/// <summary>
/// Handles the movement of the mouse in the column header.
/// </summary>
/// <param name="e">The mouse movement event arguments.</param>
protected override void OnMouseMove(MouseEventArgs e)
{
// This gets the location of the mouse in document coordinates.
Point mouseLocation = e.GetPosition(this);
// FogBugz Case #75 - (NP) 20090319 - if we past the end of the columns on the left most column
// then set the x location of the mouse to zero.
// Now this solves the problem for this case but might cause other problems.
// To resolve if there are other problems then and allow selectedColumn to be negative
// and set selectedColumn for each "case" conditon below.
// Otherwise selectedColumn will be null and cause this issue.
// Current testing appear this fix will work.
if (mouseLocation.X < 0)
{
mouseLocation.X = 0.0;
}
// The selectedColumn is the one over which the mouse is currently.
ReportColumn selectedColumn = this.ReportGrid.Columns.FindColumnAt(mouseLocation.X);
// The action taken by a mouse movement in the column heading of a viewer is driven by a set of states. These states
// are driven, in turn, by where the mouse started and what buttons are pressed. They can instruct the viewer to
// resize the columns, move the column, delete the column or sort the column.
switch (this.mouseState)
{
case MouseState.Selecting:
// When dragging the mouse around the column headings, the most recent range will be replaced. The new range
// consist of every column between the anchor column and the column over which the mouse is currently.
List <ReportColumn> lastRange = this.selectedRanges[this.selectedRanges.Count - 1];
if (lastRange[lastRange.Count - 1] != selectedColumn)
{
// The idea here is to select every column between the anchor column and the currently selected column with the idea that
// this selection will replace the previous range.
int firstIndex = this.ReportGrid.Columns.IndexOf(this.anchorColumn);
int secondIndex = this.ReportGrid.Columns.IndexOf(selectedColumn);
int startIndex = firstIndex < secondIndex ? firstIndex : secondIndex;
int endIndex = firstIndex > secondIndex ? firstIndex : secondIndex;
// This will select each column between the anchor column and the one just selected and replace the last
// selected range with this newly evaluated one.
lastRange.Clear();
for (int index = startIndex; index <= endIndex; index++)
{
ReportColumn reportColumn = this.ReportGrid.Columns[index] as ReportColumn;
if (!lastRange.Contains(reportColumn))
{
lastRange.Add(reportColumn);
}
}
// This will select all the cells in the range of columns that have been selected. Everything else will be
// cleared. The active cell -- the one that has the input focus -- is the first cell of the anchor column.
SelectCells();
}
break;
case MouseState.ResizingColumn:
// This will calculate the current column width based on the difference between the anchor ponit and the current
// mouse location.
double columnWidth = this.anchorColumn.Width + (mouseLocation.X - this.anchorPoint.X);
// The owner of the header canvas is called to draw the column boundary line so that it follows the mouse when the
// user is resizing the columns. This operation can't be done from this canvas because the size of the scrolling
// canvas -- where the column boundary cursor line is displayed -- isn't known here.
if (this.ResizeMouseMove != null)
{
this.ResizeMouseMove(this, new ResizeColumnEventArgs(this.anchorColumn, columnWidth, false));
}
// As the size of the column is dragged around, the Popup widow displays a human readable form of the width.
this.columnWidthPopup.Content = columnWidth;
break;
case MouseState.ButtonDown:
// When the user presses the left mouse button, they initiate some drag operation and the mouse activity is
// captured by the column header window. If the user is simply moving the mouse over the window, then feedback is
// given in the shape of the cursor. This formula determins if the mouse has moved an absolute distance of four
// pixels from the original location. If it has, the user has selected a movement operation for the column.
// Otherwise, the mouse operation will be interpreted as a request for a new sort order when the left mouse button
// is lifted.
if (Math.Sqrt(Math.Pow(mouseLocation.X - this.mouseDownLocation.X, 2.0) +
Math.Pow(mouseLocation.Y - this.mouseDownLocation.Y, 2.0)) > DynamicReport.headerDragTrigger)
{
// At this point the mouse movements are intepreted as drag-and-drop operations for the column headers. The
// drop states determines what happens when the mouse button is released. It can either be moved, deleted or
// have no action taken.
this.mouseState = MouseState.DraggingColumn;
this.destinationState = DropAction.NoAction;
// When dragging a column, the proposed destination appears as a set of two red arrows marking where the column
// will reside if dropped. The scale of the destination arrows must match the scale of the report.
this.destinationPopup.Scale = this.ReportGrid.DynamicReport.Scale;
this.destinationPopup.Visibility = Visibility.Hidden;
this.destinationPopup.IsOpen = true;
// This sets up the dragging operation by creating a destination cursor (the red arrows that point to where the
// column will 'snap' into place), a column cursor (it looks like the column header was ripped out of the page)
// and positions the column cursor at the tip of the current mouse location.
this.headerPopup.Resources = this.ReportGrid.Resources;
this.headerPopup.Content = this.headerCells;
this.headerPopup.Scale = this.ReportGrid.DynamicReport.Scale;
this.headerPopup.Width = selectedColumn.Width;
this.headerPopup.Height = this.ActualHeight;
this.headerPopup.Location = mouseLocation;
this.headerPopup.IsOpen = true;
}
break;
case MouseState.DraggingColumn:
// If the window that contains the column headings contains the cursor, then it's possible that a destination is
// selected for the column drag-and-drop operation. If the cursor is outside of the header quadrant, the column
// will be deleted when the mouse button is released.
if (this.Viewport.Contains(mouseLocation))
{
// Any operation inside the visible header gets the basic pointing arrow for a cursor.
this.Cursor = this.selectColumn;
// When the mouse is inside the header quadrant but there is no destination selected, then nothing will happen
// when the mouse button is release.
this.destinationState = DropAction.NoAction;
// This attempts to find a destination for the column operation.
if (selectedColumn != null)
{
// A column can't be its own destination.
if (this.anchorColumn != selectedColumn)
{
// A destination is selected if the left edge of the target column is entirely visible in the header
// quadrant and the left half of the column header contains the current mouse location.
Rect testAreaLeft = new Rect(selectedColumn.Left, this.Viewport.Top, selectedColumn.Width / 2.0,
this.Viewport.Height);
if (testAreaLeft.Contains(mouseLocation) && this.anchorColumn.Right != selectedColumn.Left)
{
this.destinationState = DropAction.Select;
this.destinationColumn = selectedColumn;
}
// This will test the right half of each of the colum headers. If the cursor is over the right half
// and the rightmost part of the destination is entirely visible in the header, then it can be a
// destination.
Rect testAreaRight = new Rect(selectedColumn.Left + selectedColumn.Width / 2.0, this.Viewport.Top,
selectedColumn.Width / 2.0, this.Viewport.Height);
if (testAreaRight.Contains(mouseLocation) && selectedColumn.Right != this.anchorColumn.Left)
{
this.destinationState = DropAction.Select;
int index = this.ReportGrid.Columns.IndexOf(selectedColumn);
this.destinationColumn = index + 1 == this.ReportGrid.Columns.Count ? null :
this.ReportGrid.Columns[index + 1] as ReportColumn;
}
}
}
// If a valid destination was found in the search above, move the set of red arrows (the destination cursor)
// over the exact spot where the column will be moved.
if (this.destinationState == DropAction.Select)
{
this.destinationPopup.HorizontalOffset = this.destinationColumn == null ?
this.ReportGrid.ExtentWidth : this.destinationColumn.Left;
this.destinationPopup.Visibility = Visibility.Visible;
}
else
{
this.destinationPopup.Visibility = Visibility.Hidden;
}
}
else
{
// If the mouse isn't over the column header quadrant, a big 'X' instead of the destination cursor give the
// user feedback that the column will be dropped from the viewer if they release the mouse button.
this.destinationPopup.Visibility = Visibility.Hidden;
this.Cursor = this.bigEx;
// This will instruct the 'mouse up' action to delete the currently selected column.
this.destinationState = DropAction.Delete;
}
// The cursor column is really a floating window, not a cursor. It needs to be moved to match the location of the
// mouse. Note that the floating window doesn't have a parent, so the coordinates are in screen units.
this.headerPopup.Location = mouseLocation;
break;
case MouseState.ButtonUp:
// This will determine which cursor should be used when the button isn't pressed while moving the mouse: a
// vertical size cursor or a regular arrow cursor. If the mouse is over the right or left edge of the column,
// then the vertical resizing cursor is used.
bool isResizingColumn = false;
// This will attempt to hit test the current column to see if it is a candidate for resizing.
if (selectedColumn != null)
{
// This is a 'Hit Test' for the right edge of the column header tile to see if the user is trying to
// change the size of the column.
if (selectedColumn.Left + selectedColumn.Width - DynamicReport.splitBorder <= mouseLocation.X &&
mouseLocation.X < selectedColumn.Left + selectedColumn.Width)
{
isResizingColumn = true;
}
// This is a 'Hit Test' for the left edge of the column header tile to see if the user is trying to change
// the size of the column.
if (selectedColumn.Left <= mouseLocation.X &&
mouseLocation.X < selectedColumn.Left + DynamicReport.splitBorder)
{
isResizingColumn = true;
}
}
// Only the selection cursor is used when the header is frozen. When unfrozen, select the resizing cursor when
// the mouse is over the edge of the column header.
this.Cursor = this.IsHeaderFrozen || !isResizingColumn ? this.selectColumn : this.verticalSplit;
break;
}
}
/// <summary>
/// Handles the mouse button being released over a column header.
/// </summary>
/// <param name="state">The thread initialization parameter.</param>
protected override void OnMouseUp(MouseButtonEventArgs e)
{
// This gets the location of the mouse in document coordinates.
Point mouseLocation = e.GetPosition(this);
// Evaluate the state of the keyboard. Key combinations involving the shift and control keys will alter the areas that
// are selected.
bool isShiftKeyPressed = ((Keyboard.Modifiers & ModifierKeys.Shift) == ModifierKeys.Shift);
bool isControlKeyPressed = ((Keyboard.Modifiers & ModifierKeys.Control) == ModifierKeys.Control);
// The mouse state indications what action should be taken when the mouse button is released.
switch (this.mouseState)
{
case MouseState.ResizingColumn:
// At the conclusion of the resizing operation a decision is made to remove or change the width of a column. If
// the size is reduced to zero (or less), this gesture is taken as a command to remove the column. Any positive
// value for a width will result in a column change command.
double columnWidth = this.anchorColumn.Width + (mouseLocation.X - this.anchorPoint.X);
columnWidth = columnWidth < 0.0 ? 0.0 : columnWidth;
if (this.ResizeMouseMove != null)
{
this.ResizeMouseMove(this, new ResizeColumnEventArgs(this.anchorColumn, columnWidth, true));
}
if (columnWidth <= 0)
{
this.ReportGrid.Columns.Remove(this.anchorColumn);
}
else
{
this.ReportGrid.Columns.SetColumnWidth(this.anchorColumn, columnWidth);
}
// This will hide the popup until it is needed again.
this.columnWidthPopup.IsOpen = false;
// This is a momentary button: the column heading will loose the selection state when the button is released.
foreach (ReportCell reportCell in this.headerCells)
{
reportCell.IsSelected = false;
}
break;
case MouseState.ButtonDown:
// This will sort the document by one or more selected columns. The control key is used to select multiple columns
// similar to the selection mode of Microsoft Office. The first step to sorting is to find out which column in the
// view has been selected for sorting.
ReportColumn reportColumn = this.ReportGrid.Columns.FindColumnAt(mouseLocation.X);
ReportField fieldDefinition = this.ReportGrid.Fields[reportColumn.ColumnId];
// The 'SortTemplate' attribute is used to distinguish columns that can be selected (usually columns that have user
// input can be selected) versus columns that can be sorted.
if (!fieldDefinition.IsSelectable)
{
// If the control key is kept pressed, then the selected sort columns will be combined. Otherwise, any
// previously selected sort column is discarded.
if (!isControlKeyPressed)
{
while (this.sortOrder.Count > 1 && this.sortOrder[this.sortOrder.Count - 1].Column != fieldDefinition)
{
this.sortOrder.Remove(this.sortOrder[0]);
}
}
// The direction of the sorting in a column can be toggled each time it is selected. This requires a test to
// make sure that the same column has been selected. Of course, if there is nothing in the list of sorting
// columns, then the list is initialize with an ascending sort.
if (this.sortOrder.Count != 0)
{
// Find the last sort column in the sort specification. If it matches the last column selected, then the
// order of the sorting is toggled. If it doesn't match, then the column is added to the list of columns
// when the control key is pressed or used to initialize the list when the control key is not pressed.
SortItem sortItem = this.sortOrder[this.sortOrder.Count - 1];
if (sortItem.Column == fieldDefinition)
{
sortItem.SortOrder = sortItem.SortOrder == SortOrder.Ascending ? SortOrder.Descending :
SortOrder.Ascending;
}
else
{
if (!isControlKeyPressed)
{
this.sortOrder.Remove(sortItem);
}
this.sortOrder.Add(new SortItem(fieldDefinition, SortOrder.Ascending));
}
}
else
{
// This will initialize the list of sort columns when the list is empty.
this.sortOrder.Add(new SortItem(fieldDefinition, SortOrder.Ascending));
}
FluidTradeCommands.SortReport.Execute(new SortEventArgs(this.sortOrder), this);
}
// This is a momentary button: the column heading will loose the selection state when the button is released.
foreach (ReportCell reportCell in this.headerCells)
{
reportCell.IsSelected = false;
}
break;
case MouseState.DraggingColumn:
// The action taken when the dragging operation is complete depends on whether a valid destination is selected or
// whether the column is meant to be deleted.
switch (this.destinationState)
{
case DropAction.Select:
// This will move the column from its current location to the desired location.
if (this.destinationPopup.Visibility == Visibility.Visible)
{
// When the column is removed from the list, all the columns that appeared after the removed column will be shifted to
// the left. This will adjust the target index so that the column will be re-inserted into the list at the desired
// index after being removed.
int newIndex = this.destinationColumn == null ? this.ReportGrid.Columns.Count :
this.ReportGrid.Columns.IndexOf(this.destinationColumn);
int oldIndex = this.ReportGrid.Columns.IndexOf(this.anchorColumn);
newIndex = oldIndex < newIndex ? newIndex - 1 : newIndex;
this.ReportGrid.Columns.Move(oldIndex, newIndex);
}
break;
case DropAction.Delete:
// This will delete the column from the view.
this.ReportGrid.Columns.Remove(this.anchorColumn);
break;
}
// This is a momentary button: the column heading will loose the selection state when the button is released.
foreach (ReportCell reportCell in this.headerCells)
{
reportCell.IsSelected = false;
}
break;
}
// This resets the state of the mouse for the next operation.
this.mouseState = MouseState.ButtonUp;
if (this.headerPopup.IsOpen)
{
this.headerPopup.IsOpen = false;
}
// Hide the destination cursor when the mouse is released.
if (this.destinationPopup.IsOpen)
{
this.destinationPopup.IsOpen = false;
}
// Release the Hounds, errr... mouse.
Mouse.Capture(null);
}
/// <summary>
/// Handles the mouse button being pressed.
/// </summary>
/// <param name="e">The event arguments.</param>
protected override void OnMouseDown(System.Windows.Input.MouseButtonEventArgs e)
{
// This gets the location of the mouse in document coordinates.
Mouse.Capture(this);
// This state variable will control how the 'Mouse Move' and 'Mouse Up' event handlers interpret the user action. The
// 'selectedColumn' field is used as the starting point for any drag-and-drop type of operation.
this.mouseState = MouseState.ButtonDown;
// Evaluate the state of the keyboard. Key combinations involving the shift and control keys will alter the areas that
// are selected.
bool isShiftKeyPressed = ((Keyboard.Modifiers & ModifierKeys.Shift) == ModifierKeys.Shift);
bool isControlKeyPressed = ((Keyboard.Modifiers & ModifierKeys.Control) == ModifierKeys.Control);
// The mouse selected with the mouse button is used as an anchor point unless the shift key is pressed. The anchor
// point allows for ranges of columns to be selected. Everything between the anchor and the currently selected column
// will be selected when the shift key is down. This is modeled after the Excel extended range selection keys.
this.mouseDownLocation = e.GetPosition(this);
if (!isShiftKeyPressed)
{
this.anchorPoint = this.mouseDownLocation;
}
// The mouse indicates which column has been selected and the anchor indicates the starting point of the selection in
// an extended selection operation.
ReportColumn selectedColumn = this.ReportGrid.Columns.FindColumnAt(this.mouseDownLocation.X);
this.anchorColumn = this.ReportGrid.Columns.FindColumnAt(this.anchorPoint.X);
// Every cell that appears in the header canvas is considered part of the selectable header. This will collect all the
// selected cells in a list while creating a rectangle that is the union of all those selected cells.
this.headerCells.Clear();
foreach (ReportRow reportRow in this.ReportGrid.Rows)
{
ReportCell reportCell = reportRow[this.anchorColumn];
if (reportRow.Top < this.ActualHeight)
{
this.headerCells.Add(reportCell);
}
}
// Every cell that appears in the header canvas is considered part of the selectable header. This will collect all the
// selected cells in a list while creating a rectangle that is the union of all those selected cells.
Rect selectedRect = this.headerCells[0].Rect;
for (int index = 1; index < this.headerCells.Count; index++)
{
selectedRect = Rect.Union(selectedRect, this.headerCells[index].Rect);
}
// If a column is selected then the position and movement of the mouse will suggest one of several gestures that need
// to be interpreted: is a column being moved, is it being resized, is it being deleted or selected? The code below
// will begin to interpret the input gesture.
if (selectedColumn != null)
{
// The header has two modes: when the headers are frozen, only selection operations are enabled with the mouse.
// When not frozen, the columns can be moved, resized, resorted and removed.
if (this.IsHeaderFrozen)
{
// The shift and control key extend the selection operation in the same way as Microsoft Excel.
if (isShiftKeyPressed || isControlKeyPressed)
{
// When the shift key is pressed during column selection, every column between the last column selected
// and the current column is selected.
if (isShiftKeyPressed)
{
// In the unlikely event that the shift key was down during the setting of the anchor point, this will
// create a dummy entry in the list of selected column ranges.
if (this.selectedRanges.Count == 0)
{
List <ReportColumn> reportColumns = new List <ReportColumn>();
reportColumns.Add(selectedColumn);
this.selectedRanges.Add(reportColumns);
}
// The most recent range will be replaced with a new range when the mouse is dragged around the column
// headers. This has the effect of clearing the columns that are no longer selected and selecting only
// the columns between the anchor and the currently selected column.
List <ReportColumn> lastRange = this.selectedRanges[this.selectedRanges.Count - 1];
int firstIndex = this.ReportGrid.Columns.IndexOf(this.anchorColumn);
int secondIndex = this.ReportGrid.Columns.IndexOf(selectedColumn);
int startIndex = firstIndex < secondIndex ? firstIndex : secondIndex;
int endIndex = firstIndex > secondIndex ? firstIndex : secondIndex;
// This will replace the last range in the list with the new range selected from the current position
// and the anchor position.
lastRange.Clear();
for (int index = startIndex; index <= endIndex; index++)
{
lastRange.Add(this.ReportGrid.Columns[index] as ReportColumn);
}
}
// When the control key is pressed a single column is added to the range of columns selected.
if (isControlKeyPressed)
{
// This removes any previous instance of this column in the selection.
foreach (List <ReportColumn> columnRange in this.selectedRanges)
{
if (columnRange.Contains(selectedColumn))
{
columnRange.Remove(selectedColumn);
}
}
// The column is added (or re-added) at the start of the range of selected columns.
List <ReportColumn> reportColumns = new List <ReportColumn>();
reportColumns.Add(selectedColumn);
this.selectedRanges.Add(reportColumns);
}
}
else
{
// A simple selection that doesn't involve the modifier keys will clear out any previously selected ranges.
selectedRanges.Clear();
// The column is added at the start of a new range of selected columns.
List <ReportColumn> reportColumns = new List <ReportColumn>();
reportColumns.Add(selectedColumn);
this.selectedRanges.Add(reportColumns);
}
// This will select all the columns in the selected ranges of columns and remove the selection from all the
// rest of the cells.
SelectCells();
// This instructs the event handlers how the mouse movement is to be interpreted.
this.mouseState = MouseState.Selecting;
}
else
{
// The left mouse button can either select the column or begin a resizing operation. This will perform a 'Hit
// Test' to see which operation should be performed.
if (e.LeftButton == MouseButtonState.Pressed)
{
// This is a 'Hit Test' for the right edge of the column header tile to see if the user is trying to
// change the size of the column. If the mouse is close to the right edge, then the drag operation to
// change the size of the tile is begun.
if (selectedColumn.Right - DynamicReport.splitBorder <= this.mouseDownLocation.X &&
this.mouseDownLocation.X < selectedColumn.Right)
{
this.resizeStart = selectedColumn.Right;
this.mouseState = MouseState.ResizingColumn;
this.destinationColumn = null;
}
else
{
// This is a 'Hit Test' for the left edge of the column header tile to see if the user is trying to
// change the size of the column. Note that because the left edge really belongs to the previous
// column header when resizing, that the previous column is selected for the operation.
if (selectedColumn.Left <= this.mouseDownLocation.X &&
this.mouseDownLocation.X < selectedColumn.Left + DynamicReport.splitBorder)
{
this.resizeStart = selectedColumn.Left;
this.mouseState = MouseState.ResizingColumn;
int index = this.ReportGrid.Columns.IndexOf(selectedColumn);
if (index != 0)
{
this.anchorColumn = this.ReportGrid.Columns[index - 1] as ReportColumn;
this.destinationColumn = null;
}
}
}
}
// At this point, a resizing operation has been selected from the input gesture of the mouse.
if (this.mouseState == MouseState.ResizingColumn)
{
// The parent window will watch for this event to tell it how to draw the column width indicator lines. The
// dimension and location of those lines are outside of this window and must be handled by the parent.
if (this.ResizeMouseMove != null)
{
this.ResizeMouseMove(this, new ResizeColumnEventArgs(this.anchorColumn, this.anchorColumn.Width,
false));
}
// This window provides quantitative feedback for the new width of the column. The offsets were arrived at
// empirically from reverse engineering Excel.
this.columnWidthPopup.HorizontalOffset = this.mouseDownLocation.X - 2.0;
this.columnWidthPopup.Content = selectedColumn.Width;
this.columnWidthPopup.IsOpen = true;
}
else
{
// This will select the button momentarily for drag-and-drop and sorting operations.
foreach (ReportCell reportCell in this.headerCells)
{
reportCell.IsSelected = true;
}
}
}
}
}
