C# IDiagramPresenter.SelectShape方法代码示例

		// (Un)Select shape unter the mouse pointer
		private bool PerformSelection(IDiagramPresenter diagramPresenter, MouseState mouseState,
		                              ShapeAtCursorInfo shapeAtCursorInfo)
		{
			bool result = false;
			bool multiSelect = mouseState.IsKeyPressed(KeysDg.Control) || mouseState.IsKeyPressed(KeysDg.Shift);

			// When selecting shapes conteolpoints should be ignored as the user does not see them 
			// until a shape is selected
			const ControlPointCapabilities capabilities = ControlPointCapabilities.None;
			const int range = 0;

			// Determine the shape that has to be selected:
			Shape shapeToSelect = null;
			if (!selectedShapeAtCursorInfo.IsEmpty) {
				// When in multiSelection mode, unselect the selected shape under the cursor
				if (multiSelect) shapeToSelect = selectedShapeAtCursorInfo.Shape;
				else {
					// First, check if the selected shape under the cursor has children that can be selected
					shapeToSelect = selectedShapeAtCursorInfo.Shape.Children.FindShape(mouseState.X, mouseState.Y, capabilities, range,
					                                                                   null);
					// Second, check if the selected shape under the cursor has siblings that can be selected
					if (shapeToSelect == null && selectedShapeAtCursorInfo.Shape.Parent != null) {
						shapeToSelect = selectedShapeAtCursorInfo.Shape.Parent.Children.FindShape(mouseState.X, mouseState.Y, capabilities,
						                                                                          range, selectedShapeAtCursorInfo.Shape);
						// Discard found shape if it is the selected shape at cursor
						if (shapeToSelect == selectedShapeAtCursorInfo.Shape) shapeToSelect = null;
						if (shapeToSelect == null) {
							foreach (
								Shape shape in
									selectedShapeAtCursorInfo.Shape.Parent.Children.FindShapes(mouseState.X, mouseState.Y, capabilities, range)) {
								if (shape == selectedShapeAtCursorInfo.Shape) continue;
								// Ignore layer visibility for child shapes
								shapeToSelect = shape;
								break;
							}
						}
					}
				}
			}

			// If there was a shape to select related to the selected shape under the cursor
			// (a child or a sibling of the selected shape or a shape below it),
			// try to select the first non-selected shape under the cursor
			if (shapeToSelect == null && shapeAtCursorInfo.Shape != null
			    && shapeAtCursorInfo.Shape.ContainsPoint(mouseState.X, mouseState.Y))
				shapeToSelect = shapeAtCursorInfo.Shape;

			// If a new shape to select was found, perform selection
			if (shapeToSelect != null) {
				// (check if multiselection mode is enabled (Shift + Click or Ctrl + Click))
				if (multiSelect) {
					// if multiSelect is enabled, add/remove to/from selected selectedShapes...
					if (diagramPresenter.SelectedShapes.Contains(shapeToSelect)) {
						// if object is selected -> remove from selection
						diagramPresenter.UnselectShape(shapeToSelect);
						RemovePreviewOf(shapeToSelect);
						result = true;
					}
					else {
						// If object is not selected -> add to selection
						diagramPresenter.SelectShape(shapeToSelect, true);
						result = true;
					}
				}
				else {
					// ... otherwise deselect all selectedShapes but the clicked object
					ClearPreviews();
					// check if the clicked shape is a child of an already selected shape
					Shape childShape = null;
					if (diagramPresenter.SelectedShapes.Count == 1
					    && diagramPresenter.SelectedShapes.TopMost.Children != null
					    && diagramPresenter.SelectedShapes.TopMost.Children.Count > 0) {
						childShape = diagramPresenter.SelectedShapes.TopMost.Children.FindShape(mouseState.X, mouseState.Y,
						                                                                        ControlPointCapabilities.None, 0, null);
					}
					diagramPresenter.SelectShape(childShape ?? shapeToSelect, false);
					result = true;
				}

				// validate if the desired shape or its parent was selected
				if (shapeToSelect.Parent != null) {
					if (!diagramPresenter.SelectedShapes.Contains(shapeToSelect))
						if (diagramPresenter.SelectedShapes.Contains(shapeToSelect.Parent))
							shapeToSelect = shapeToSelect.Parent;
				}
			}
			else if (selectedShapeAtCursorInfo.IsEmpty) {
				// if there was no other shape to select and none of the selected shapes is under the cursor,
				// clear selection
				if (!multiSelect) {
					if (diagramPresenter.SelectedShapes.Count > 0) {
						diagramPresenter.UnselectAll();
						ClearPreviews();
						result = true;
					}
				}
			}

			return result;
//.........这里部分代码省略.........