ImageEn, unit ieview

TIEMouseWheelParamsAction


Declaration

TIEMouseWheelParamsAction = (iemwNone, iemwVScroll, iemwZoom, iemwNavigate, iemwZoomView);


Description

The effect that rolling the mouse wheel has upon a control.

Value Description
iemwNone Mouse wheel has no effect
iemwVScroll Scroll the control up/down (or left/right if Alt key is pressed, or control does not support vert scrolling)
iemwZoom Enlarge/Reduce the image (TImageEnView) or thumbnails (TImageEnMView)
iemwZoomView In TImageEnMView this cycles through the common display styles and sizes. (With TImageEnView it works the same way as iemwZoom)
iemwNavigate Navigate to the next/previous image. Note: In TImageEnView this is only relevant for images with multiple frames such as TIFFs and GIFs
Note: When using iemwZoom, you can limit the bounds of the zoom using OnZoomIn and OnZoomOut


Example

// For iemwVScroll used with iemwPercentage, TImageEnMView assumes a theoretical grid of 12.5 thumbnails high
// So the default of 8% will scroll one thumbnail with each wheel click
// Whereas 16% would scroll the height of two thumbnails
ImageEnMView1.MouseWheelParams.Action := iemwVScroll;
ImageEnMView1.MouseWheelParams.Variation := iemwPercentage;
ImageEnMView1.MouseWheelParams.value := 4; // half a thumbnail