C++ FReply::ReleaseMouseCapture方法代码示例

FReply FTextEditHelper::OnMouseButtonUp( const FGeometry& MyGeometry, const FPointerEvent& InMouseEvent, const TSharedRef< ITextEditorWidget >& TextEditor )
{
	FReply Reply = FReply::Unhandled();

	// The mouse must have been captured by either left or right button down before we'll process mouse ups
	if( TextEditor->GetWidget()->HasMouseCapture() )
	{
		if( InMouseEvent.GetEffectingButton() == EKeys::LeftMouseButton &&
			TextEditor->IsDragSelecting() )
		{
			// No longer drag-selecting
			TextEditor->EndDragSelection();

			// If we received keyboard focus on this click, then we'll want to select all of the text
			// when the user releases the mouse button, unless the user actually dragged the mouse
			// while holding the button down, in which case they've already selected some text and
			// we'll leave things alone!
			if( TextEditor->WasFocusedByLastMouseDown() )
			{
				if( !TextEditor->HasDragSelectedSinceFocused() )
				{
					if( TextEditor->SelectAllTextWhenFocused() )
					{
						// Move the cursor to the end of the string
						TextEditor->JumpTo(ETextLocation::EndOfDocument, ECursorAction::MoveCursor);

						// User wasn't dragging the mouse, so go ahead and select all of the text now
						// that we've become focused
						TextEditor->SelectAllText();

						// @todo Slate: In this state, the caret should actually stay hidden (until the user interacts again), and we should not move the caret
					}
				}

				TextEditor->SetWasFocusedByLastMouseDown( false );
			}

			// Release mouse capture
			Reply = FReply::Handled();
			Reply.ReleaseMouseCapture();
		}
		else if( InMouseEvent.GetEffectingButton() == EKeys::RightMouseButton )
		{
			if ( MyGeometry.IsUnderLocation( InMouseEvent.GetScreenSpacePosition() ) )
			{
				// Right clicked, so summon a context menu if the cursor is within the widget
				TextEditor->SummonContextMenu( InMouseEvent.GetScreenSpacePosition() );
			}

			// Release mouse capture
			Reply = FReply::Handled();
			Reply.ReleaseMouseCapture();
		}
	}

	return Reply;
}

FReply SButton::OnMouseButtonUp( const FGeometry& MyGeometry, const FPointerEvent& MouseEvent )
{
	FReply Reply = FReply::Unhandled();
	const bool bMustBePressed = ClickMethod == EButtonClickMethod::DownAndUp;
	const bool bMeetsPressedRequirements = (!bMustBePressed || (bIsPressed && bMustBePressed));

	if (bMeetsPressedRequirements && IsEnabled() && ( MouseEvent.GetEffectingButton() == EKeys::LeftMouseButton || MouseEvent.IsTouchEvent() ) )
	{
		Release();

		if( ClickMethod == EButtonClickMethod::MouseDown )
		{
			// NOTE: If we're configured to click on mouse-down/precise-tap, then we never capture the mouse thus
			//       may never receive an OnMouseButtonUp() call.  We make sure that our bIsPressed
			//       state is reset by overriding OnMouseLeave().
		}
		else
		{
			bool bEventOverButton = IsHovered();
			if (!bEventOverButton && MouseEvent.IsTouchEvent())
			{
				bEventOverButton = MyGeometry.IsUnderLocation(MouseEvent.GetScreenSpacePosition());
			}
			if (bEventOverButton)
			{
				// If we asked for a precise tap, all we need is for the user to have not moved their pointer very far.
				const bool bTriggerForTouchEvent = IsPreciseTapOrClick(MouseEvent);

				// If we were asked to allow the button to be clicked on mouse up, regardless of whether the user
				// pressed the button down first, then we'll allow the click to proceed without an active capture
				const bool bTriggerForMouseEvent = ( ClickMethod == EButtonClickMethod::MouseUp || HasMouseCapture() );

				if( (bTriggerForTouchEvent || bTriggerForMouseEvent) && OnClicked.IsBound() == true )
				{
					Reply = OnClicked.Execute();
				}
			}
		}
		
		//If the user of the button didn't handle this click, then the button's
		//default behavior handles it.
		if ( Reply.IsEventHandled() == false )
		{
			Reply = FReply::Handled();
		}

		//If the user hasn't requested a new mouse captor and the button still has mouse capture,
		//then the default behavior of the button is to release mouse capture.
		if (Reply.GetMouseCaptor().IsValid() == false && HasMouseCapture())
		{
			Reply.ReleaseMouseCapture();
		}
	}

	Invalidate(EInvalidateWidget::Layout);

	return Reply;
}

FReply FWebBrowserViewport::OnMouseButtonUp(const FGeometry& MyGeometry, const FPointerEvent& MouseEvent)
{
	// Release mouse capture when left button released
	FReply Reply = WebBrowserWindow->OnMouseButtonUp(MyGeometry, MouseEvent);
	if (MouseEvent.GetEffectingButton() == EKeys::LeftMouseButton)
	{
		return Reply.ReleaseMouseCapture();
	}
	return Reply;
}

FReply SPaperEditorViewport::OnMouseButtonUp(const FGeometry& MyGeometry, const FPointerEvent& MouseEvent)
{
	// Did the user move the cursor sufficiently far, or is it in a dead zone?
	// In Dead zone     - implies actions like summoning context menus and general clicking.
	// Out of Dead Zone - implies dragging actions like moving nodes and marquee selection.
	const bool bCursorInDeadZone = TotalMouseDelta <= FSlateApplication::Get().GetDragTriggerDistance();

	if (MouseEvent.GetEffectingButton() == EKeys::RightMouseButton)
	{
		FReply ReplyState = FReply::Handled();

		if (HasMouseCapture())
		{
			FSlateRect ThisPanelScreenSpaceRect = MyGeometry.GetClippingRect();
			const FVector2D ScreenSpaceCursorPos = MyGeometry.LocalToAbsolute( GraphCoordToPanelCoord( SoftwareCursorPosition ) );

			FIntPoint BestPositionInViewport(
				FMath::RoundToInt( FMath::Clamp( ScreenSpaceCursorPos.X, ThisPanelScreenSpaceRect.Left, ThisPanelScreenSpaceRect.Right ) ),
				FMath::RoundToInt( FMath::Clamp( ScreenSpaceCursorPos.Y, ThisPanelScreenSpaceRect.Top, ThisPanelScreenSpaceRect.Bottom ) )
				);

			if (!bCursorInDeadZone)
			{
				ReplyState.SetMousePos(BestPositionInViewport);
			}
		}

		TSharedPtr<SWidget> WidgetToFocus;
		if (bCursorInDeadZone)
		{
			//WidgetToFocus = OnSummonContextMenu(MyGeometry, MouseEvent);
		}

		bShowSoftwareCursor = false;

		bIsPanning = false;
		return (WidgetToFocus.IsValid())
			? ReplyState.ReleaseMouseCapture().SetUserFocus(WidgetToFocus.ToSharedRef(), EFocusCause::SetDirectly)
			: ReplyState.ReleaseMouseCapture();
	}
	else if (MouseEvent.GetEffectingButton() == EKeys::LeftMouseButton)
	{
		if (OnHandleLeftMouseRelease(MyGeometry, MouseEvent))
		{

		}
		else if (bCursorInDeadZone)
		{
			//@TODO: Move to selection manager
// 			if ( NodeUnderMousePtr.IsValid() )
// 			{
// 				// We clicked on a node!
// 				TSharedRef<SNode> NodeWidgetUnderMouse = NodeUnderMousePtr.Pin().ToSharedRef();
// 
// 				SelectionManager.ClickedOnNode(NodeWidgetUnderMouse->GetObjectBeingDisplayed(), MouseEvent);
// 
// 				// We're done interacting with this node.
// 				NodeUnderMousePtr.Reset();
// 			}
// 			else 
			if (HasMouseCapture())
 			{
 				// We clicked on the panel background

				//@TODO: There isn't a marquee operation for clear, need to signal to remove existing sets too!
				//Marquee.End();
 				//OnSelectionChanged.ExecuteIfBound(Marquee, false);
 			}
		}
		else if (Marquee.IsValid())
		{
			//ApplyMarqueeSelection(Marquee, SelectionManager.SelectedNodes, SelectionManager.SelectedNodes);
			//SelectionManager.OnSelectionChanged.ExecuteIfBound(SelectionManager.SelectedNodes);
			OnSelectionChanged.ExecuteIfBound(Marquee, true);
		}

		// The existing marquee operation ended; reset it.
		Marquee = FMarqueeOperation();

		if (bIsPanning)
		{
			// We have released the left mouse button. But we're still panning
			// (i.e. RIGHT MOUSE is down), so we want to hold on to capturing mouse input.
			return FReply::Handled();
		}
		else
		{
			// We aren't panning, so we can release the mouse capture.
			return FReply::Handled().ReleaseMouseCapture();
		}	
	}

	return FReply::Unhandled();	
}