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Declaration

TImageEnMView = class(TIECustomMView);

Description

The TImageEnMView is a display component for multiple images (frames of a video or multiple image format, like GIF, or thumbnails of images, e.g. images in a folder).
It embeds a multiple image container, TIEMultiBitmap (IEMBitmap property), and can display images in two ways:
◼As a grid of thumbnails (similar to a thumbnail view in Windows Explorer)
◼As a single frame of a multiple-frame image (such as a GIF, AVI or TIFF). This can also be animated.


TImageEnMView encapsulates a TImageEnMIO (MIO property) for loading, saving, acquisition and printing, and a TImageEnProc (Proc property) for editing of the selected image.
Frames can be loaded and saved from multiple image formats like GIF, TIFF, AVI, DCX, DICOM and ICO. It can also load from CUR and ZIP formats, and save to PDF and PS format (loading of PDF is supported if a relevant plug-in is installed).

The images can be stored as full images, as thumbnails (a sub-resampled image of the original), loaded only as they are displayed (you need only specify the file name), or upon request (an event is generated whenever an image needs to be shown).
Thumbnails for video formats are retrieved from Windows Explorer. This can be disabled or expanded by setting MViewExplorerThumbnailExts.

For rapid UI development a full set of actions is also available.

There are two descendent components of TImageEnMView:

• TImageEnFolderMView: For displaying images in a folder
• TImageEnLayerMView: For displaying layers of an image

TImageEnMView supports VCL Theming:

Overview

       

Display Styles

TImageEnMView offers five standard styles. Ensure you set AutoAdjustStyle := True; so that setting the style automatically updates all relevant properties.

Thumbnail Performance

Because a TImageEnMView may potentially load and store thousands of files, you should optimize your settings to ensure the best performance. Take note of the following:

• Most importantly, decide whether to load and store full size images, or just preview thumbnails. If you are loading the content of a multi-page file, such as TIFF, for editing and display, then generally you will want StoreType=ietNormal. However, if you are displaying thousands of photos from a folder, for example, then you are better to use load only thumbnails (StoreType is ietThumb or ietFastThumb)
• Load images only on demand (i.e. as they are displayed or needed). To do this, ensure the LoadOnDemand parameter is set for AppendImage, InsertImage, FillFromDirectory or FillFromList. Or if you are just loading a single file with many pages, use LoadFromFileOnDemand
• Lock updating while performing batch operations (LockUpdate/UnlockUpdate)
• Consider options to load EXIF thumbnails or Windows Explorer thumbnails
• Choose a good balance between quality and speed when setting the ThumbnailResampleFilter
• Increasing the size of the image cache can help with general performance, especially when StoreType=ietFastThumb
• Set DeprioritizeLargeImages to a size larger than most images to prevent very large images from slowing the display

Recommended Defaults

For compatibility, some of the default options of TImageEnMView are not the recommended ones. Here are some suggested changes:

• Enable AutoAdjustStyle so you that setting Style will automatically update relevant layout properties:
    ImageEnMView1.AutoAdjustStyle := True;
• Call SetModernStyling to update the styling:
    ImageEnMView1.SetModernStyling();
• Increase the size of the thumbnails (ThumbWidth/ThumbHeight):
    ImageEnMView1.ThumbWidth  := 140;
    ImageEnMView1.ThumbHeight := 120;
• Enable selection of multiple thumbnails:
    ImageEnMView1.EnableMultiSelect := True;
• Use form fonts for thumbnail text:
    ImageEnMView1.ParentFont := True;

Keyboard Shortcuts

The following keyboard shortcuts are supported:
Note: Configure or disable individual keyboard shortcuts using KeyboardShortcuts

Debugging Visualizer

You can view the content of a TImageEnMView while debugging by hovering over the object and clicking the Inspect button:

Demos

Examples

procedure TForm1.FormCreate(Sender: TObject);
begin
  // Setup TImageEnMView
  ImageEnMView1.SetModernStyling(False);         // Update to the most modern styling
  ImageEnMView1.AutoAdjustStyle   := True;       // Enable so that setting "Style" will automatically update all relevant properties
  ImageEnMView1.GridWidth         := -1;         // Automatically adjust the column count to match the control width
  ImageEnMView1.ThumbWidth        := 150;        // Increase size of thumbnails
  ImageEnMView1.ThumbHeight       := 130;        // Increase size of thumbnails
  ImageEnMView1.EnableMultiSelect := true;       // Enable selection of multiple files
  ImageEnMView1.StoreType         := ietThumb;   // Normally don't need to store whole image in memory, just a sub-sampled thumbnail
end;

// Now display the images of a folder in the grid
ImageEnMView1.FillFromDirectory('C:\MyImages\', -1, False, '', False, '', True);

// Create an animated GIF file from ten source images
ImageEnMView1.Clear;
for i := 0 to 9 do
begin
  ImageEnMView1.AppendImage( format( 'D:\Source\Frame %d.bmp', [i] ));
  ImageEnMView1.MIO.Params[i].GIF_DelayTime := 10; // Display each frame for 1/10th of a second
end;
ImageEnMView1.MIO.SaveToFileGIF( 'D:\Animated.gif' );

Methods and Properties

Embedded Components

Display

Editing

Image Access

Image Information

Image Text

Thumbnail Appearance

Thumbnail Spacing

Input/Output

Selections

Checkboxes

User Interaction

ScrollBars

Single Frame View

Other

Events

User Interaction Events

Loading Events

Paint Events

Other Events

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