imageViewer Property

Summary

Image viewer control.

Syntax
TypeScript
JavaScript
Object.defineProperty(DocumentViewerView.prototype, 'imageViewer', 
	get: function() 
) 
imageViewer: ImageViewer; // read-only

Property Value

The ImageViewer control used to view the main content of the document.

Remarks

ImageViewer is initialized during CreateDocumentViewer. A new instance of ImageViewer is created and set in this property. The control is added as a child to DocumentViewerCreateOptions.ViewContainer and initialized as follows:

Member Description

ViewHorizontalAlignment and ViewVerticalAlignment

Center

ImageHorizontalAlignment and ImageVerticalAlignment

Center

ImageBorderThickness

1

ImageBackgroundColor

White color

ItemPadding

4, 4, 4, 4

UseDpi

true

ImageViewer.Tag

Set to the owner DocumentViewer. Be careful not to modify this value in your application.

In addition to the above, the document viewer subscribes to the PostRenderItem event to render the current text selection used by DocumentViewer.Text, the annotations for the pages used by Annotations and any optional debugging rendering done by DocumentViewer.Diagnostics.

After CreateDocumentViewer returns, you can further customize or use this ImageViewer control as needed by your application.

Example
View.ts
ViewerInitializer.ts
View.js
ViewerInitializer.js
View.html
examples.css 
import { ViewerInitializer } from "../utilities/ViewerInitializer"; 
 
export class ViewTSExample { 
   public run = () => { 
      new ViewerInitializer(this.addViewHook); 
   } 
 
   addViewHook = (documentViewer: lt.Document.Viewer.DocumentViewer) => { 
      // Get the view 
      const view = documentViewer.view; 
      // Get its image viewer 
      const imageViewer = view.imageViewer; 
 
      // Hook to the PostRender 
      imageViewer.postRenderItem.add((sender, e) => { 
         // Get the image viewer item for the page 
         const item = e.item; 
 
         // Build the text we want. The page number is the item index + 1 
         const pageNumber = imageViewer.items.indexOf(item) + 1; 
         const text = "Page " + pageNumber; 
 
         // Get the image transformation for this item 
         const transform = imageViewer.getItemImageTransform(e.item); 
 
         // Apply it to the context 
         const ctx = e.context; 
         ctx.save(); 
         ctx.transform(transform.m11, transform.m12, transform.m21, transform.m22, transform.offsetX, transform.offsetY); 
 
         // Render the text 
         ctx.fillStyle = "red"; 
         ctx.font = "60pt bold Times New Roman"; 
         ctx.fillText(text, 70, 70); 
         ctx.restore(); 
      }); 
 
      // Invalidate so our changes take effect the first time 
      view.invalidate(lt.LeadRectD.empty); 
   } 
} 
export class ViewerInitializer { 
   private callback: (viewer: lt.Document.Viewer.DocumentViewer) => void = null; 
 
   constructor(callback?: (viewer: lt.Document.Viewer.DocumentViewer) => void) { 
      this.callback = callback; 
      this.init(); 
   } 
 
   public static showServiceError = (jqXHR, statusText, errorThrown) => { 
      alert('Error returned from service. See the console for details.') 
      const serviceError = lt.Document.ServiceError.parseError(jqXHR, statusText, errorThrown); 
      console.error(serviceError); 
   } 
 
   private init = () => { 
      this.initFactory(); 
      this.testConnection(); 
   } 
 
   private initFactory = () => { 
      lt.RasterSupport.setLicenseUri('https://demo.leadtools.com/licenses/js/LEADTOOLSEVAL.txt', 'EVAL', null); 
 
      // To communicate with the DocumentsService, it must be running! 
      // Change these parameters to match the path to the service. 
      lt.Document.DocumentFactory.serviceHost = 'http://localhost:40000'; 
      lt.Document.DocumentFactory.servicePath = ''; 
      lt.Document.DocumentFactory.serviceApiPath = 'api'; 
   } 
 
   private testConnection = () => { 
      const serviceStatus = document.getElementById('serviceStatus'); 
      serviceStatus.innerHTML = 'Connecting to service: ' + lt.Document.DocumentFactory.serviceUri; 
 
      lt.Document.DocumentFactory.verifyService() 
         .done((serviceData) => { 
            serviceStatus.innerHTML = 'Service connection verified!'; 
            this.createDocumentViewer(); 
         }) 
         .fail((jqXHR, statusText, errorThrown) => { 
            serviceStatus.innerHTML = 'Service connection unavailable.'; 
            ViewerInitializer.showServiceError(jqXHR, statusText, errorThrown); 
         }); 
   } 
 
   private createDocumentViewer = () => { 
      // Initialize the user interface 
      const interactiveSelect = document.getElementById('interactiveSelect'); 
 
      const panZoomOption = document.createElement('option'); 
      panZoomOption.innerHTML = 'Pan / Zoom'; 
      panZoomOption.value = lt.Document.Viewer.DocumentViewerCommands.interactivePanZoom; 
      interactiveSelect.appendChild(panZoomOption); 
 
      const textOption = document.createElement('option'); 
      textOption.value = lt.Document.Viewer.DocumentViewerCommands.interactiveSelectText; 
      textOption.innerHTML = 'Select Text'; 
      interactiveSelect.appendChild(textOption); 
 
      let documentViewer: lt.Document.Viewer.DocumentViewer = null; 
      interactiveSelect.onchange = (e) => documentViewer.commands.run((e.target as HTMLSelectElement).value, null); 
 
      const annotationsSelect = document.getElementById('annotationsSelect'); 
 
      const annSelectOption = document.createElement('option'); 
      annSelectOption.innerHTML = 'Select Annotation'; 
      annSelectOption.value = lt.Annotations.Engine.AnnObject.selectObjectId.toString(); 
      annotationsSelect.appendChild(annSelectOption); 
 
      const annLineOption = document.createElement('option'); 
      annLineOption.innerHTML = 'Line Object'; 
      annLineOption.value = lt.Annotations.Engine.AnnObject.lineObjectId.toString(); 
      annotationsSelect.appendChild(annLineOption); 
 
      const annRectOption = document.createElement('option'); 
      annRectOption.innerHTML = 'Rectangle Object'; 
      annRectOption.value = lt.Annotations.Engine.AnnObject.rectangleObjectId.toString(); 
      annotationsSelect.appendChild(annRectOption); 
      annotationsSelect.onchange = (e) => { 
         const value = +(e.currentTarget as HTMLSelectElement).value; 
         documentViewer.annotations.automationManager.currentObjectId = value; 
      } 
 
      // Init the document viewer, pass along the panels 
      const createOptions = new lt.Document.Viewer.DocumentViewerCreateOptions(); 
      // We are not going to use elements mode in this example 
      createOptions.viewCreateOptions.useElements = false; 
      createOptions.thumbnailsCreateOptions.useElements = false; 
 
      // The middle panel for the view 
      createOptions.viewContainer = document.getElementById('viewer'); 
      // The left panel for the thumbnails 
      createOptions.thumbnailsContainer = document.getElementById('thumbnails'); 
      // The right panel is for bookmarks 
      createOptions.bookmarksContainer = document.getElementById('bookmarks'); 
      createOptions.useAnnotations = true; 
 
      // Create the document viewer 
      documentViewer = lt.Document.Viewer.DocumentViewerFactory.createDocumentViewer(createOptions); 
 
      // We prefer SVG viewing 
      documentViewer.view.preferredItemType = lt.Document.Viewer.DocumentViewerItemType.svg; 
 
      // Create html5 rendering engine 
      documentViewer.annotations.automationManager.renderingEngine = new lt.Annotations.Rendering.AnnHtml5RenderingEngine(); 
      // Initialize documentViewer annotations 
      documentViewer.annotations.initialize(); 
 
      documentViewer.annotations.automationManager.currentObjectIdChanged.add(function (sender, e) { 
         // When done drawing, the manager will return to the select object; so we need force the annotationsSelect element to return to the select object option 
         (annotationsSelect as HTMLSelectElement).value = sender.currentObjectId; 
      }); 
 
      this.loadDefaultDoc(documentViewer, interactiveSelect as HTMLSelectElement) 
   } 
 
   private loadDefaultDoc = (viewer: lt.Document.Viewer.DocumentViewer, interactiveSelect: HTMLSelectElement) => { 
      // Load a PDF document 
      const url = 'https://demo.leadtools.com/images/pdf/leadtools.pdf'; 
      lt.Document.DocumentFactory.loadFromUri(url, null) 
         .done((doc: lt.Document.LEADDocument) => { 
            const ready = () => { 
               viewer.setDocument(doc); 
               const panZoom = lt.Document.Viewer.DocumentViewerCommands.interactivePanZoom; 
               interactiveSelect.value = panZoom; 
               viewer.commands.run(panZoom, null); 
               if(this.callback) 
                  this.callback(viewer); 
            } 
 
            if (doc.isStructureSupported && !doc.structure.isParsed) 
               doc.structure.parse() 
                  .done(ready) 
                  .fail(ViewerInitializer.showServiceError); 
            else 
               ready(); 
         }) 
         .fail(ViewerInitializer.showServiceError); 
   } 
} 
import { ViewerInitializer } from "../utilities/ViewerInitializer"; 
 
export class ViewJSExample { 
   constructor() { } 
 
   run = () => { 
      new ViewerInitializer(this.addViewHook); 
   } 
 
   addViewHook = (documentViewer) => { 
      // Get the view 
      const view = documentViewer.view; 
      // Get its image viewer 
      const imageViewer = view.imageViewer; 
 
      // Hook to the PostRender 
      imageViewer.postRenderItem.add(function (sender, e) { 
         // Get the image viewer item for the page 
         const item = e.item; 
 
         // Build the text we want. The page number is the item index + 1 
         const pageNumber = imageViewer.items.indexOf(item) + 1; 
         const text = "Page " + pageNumber; 
 
         // Get the image transformation for this item 
         const transform = imageViewer.getItemImageTransform(e.item); 
 
         // Apply it to the context 
         const ctx = e.context; 
         ctx.save(); 
         ctx.transform(transform.m11, transform.m12, transform.m21, transform.m22, transform.offsetX, transform.offsetY); 
 
         // Render the text 
         ctx.fillStyle = "red"; 
         ctx.font = "60pt bold Times New Roman"; 
         ctx.fillText(text, 70, 70); 
         ctx.restore(); 
      }); 
 
      // Invalidate so our changes take effect the first time 
      view.invalidate(lt.LeadRectD.empty); 
   } 
} 
export class ViewerInitializer { 
   constructor(callback) { 
      this.callback = callback; 
      this.init(); 
   } 
 
   static showServiceError = (jqXHR, statusText, errorThrown) => { 
      alert("Error returned from service. See the console for details.") 
      const serviceError = lt.Document.ServiceError.parseError(jqXHR, statusText, errorThrown); 
      console.error(serviceError); 
   } 
 
   init = () => { 
      this.initFactory(); 
      this.testConnection(); 
   } 
 
   initFactory = () => { 
      lt.RasterSupport.setLicenseUri("https://demo.leadtools.com/licenses/js/LEADTOOLSEVAL.txt", "EVAL", null); 
 
      // To communicate with the DocumentsService, it must be running! 
      // Change these parameters to match the path to the service. 
      lt.Document.DocumentFactory.serviceHost = "http://localhost:40000"; 
      lt.Document.DocumentFactory.servicePath = ""; 
      lt.Document.DocumentFactory.serviceApiPath = "api"; 
   } 
 
   testConnection = () => { 
      const serviceStatus = document.getElementById("serviceStatus"); 
      serviceStatus.innerHTML = "Connecting to service: " + lt.Document.DocumentFactory.serviceUri; 
 
      lt.Document.DocumentFactory.verifyService() 
         .done((serviceData) => { 
            serviceStatus.innerHTML = "Service connection verified!"; 
            this.createDocumentViewer(); 
         }) 
         .fail((jqXHR, statusText, errorThrown) => { 
            serviceStatus.innerHTML = "Service connection unavailable."; 
            ViewerInitializer.showServiceError(jqXHR, statusText, errorThrown); 
         }); 
   } 
 
   createDocumentViewer = () => { 
      // Initialize the user interface 
      const interactiveSelect = document.getElementById("interactiveSelect"); 
 
      const panZoomOption = document.createElement("option"); 
      panZoomOption.innerHTML = "Pan / Zoom"; 
      panZoomOption.value = lt.Document.Viewer.DocumentViewerCommands.interactivePanZoom; 
      interactiveSelect.appendChild(panZoomOption); 
 
      const textOption = document.createElement("option"); 
      textOption.value = lt.Document.Viewer.DocumentViewerCommands.interactiveSelectText; 
      textOption.innerHTML = "Select Text"; 
      interactiveSelect.appendChild(textOption); 
 
      let documentViewer = null; 
      interactiveSelect.onchange = (e) => documentViewer.commands.run(e.target.value, null); 
 
      const annotationsSelect = document.getElementById("annotationsSelect"); 
 
      const annSelectOption = document.createElement("option"); 
      annSelectOption.innerHTML = "Select Annotation"; 
      annSelectOption.value = lt.Annotations.Engine.AnnObject.selectObjectId.toString(); 
      annotationsSelect.appendChild(annSelectOption); 
 
      const annLineOption = document.createElement("option"); 
      annLineOption.innerHTML = "Line Object"; 
      annLineOption.value = lt.Annotations.Engine.AnnObject.lineObjectId.toString(); 
      annotationsSelect.appendChild(annLineOption); 
 
      const annRectOption = document.createElement("option"); 
      annRectOption.innerHTML = "Rectangle Object"; 
      annRectOption.value = lt.Annotations.Engine.AnnObject.rectangleObjectId.toString(); 
      annotationsSelect.appendChild(annRectOption); 
      annotationsSelect.onchange = (e) => { 
         const value = +e.currentTarget.value; 
         documentViewer.annotations.automationManager.currentObjectId = value; 
      } 
 
      // Init the document viewer, pass along the panels 
      const createOptions = new lt.Document.Viewer.DocumentViewerCreateOptions(); 
      // We are not going to use elements mode in this example 
      createOptions.viewCreateOptions.useElements = false; 
      createOptions.thumbnailsCreateOptions.useElements = false; 
 
      // The middle panel for the view 
      createOptions.viewContainer = document.getElementById("viewer"); 
      // The left panel for the thumbnails 
      createOptions.thumbnailsContainer = document.getElementById("thumbnails"); 
      // The right panel is for bookmarks 
      createOptions.bookmarksContainer = document.getElementById("bookmarks"); 
      createOptions.useAnnotations = true; 
 
      // Create the document viewer 
      documentViewer = lt.Document.Viewer.DocumentViewerFactory.createDocumentViewer(createOptions); 
 
      // We prefer SVG viewing 
      documentViewer.view.preferredItemType = lt.Document.Viewer.DocumentViewerItemType.svg; 
 
      // Create html5 rendering engine 
      documentViewer.annotations.automationManager.renderingEngine = new lt.Annotations.Rendering.AnnHtml5RenderingEngine(); 
      // Initialize documentViewer annotations 
      documentViewer.annotations.initialize(); 
 
      documentViewer.annotations.automationManager.currentObjectIdChanged.add(function (sender, e) { 
         // When done drawing, the manager will return to the select object; so we need force the annotationsSelect element to return to the select object option 
         annotationsSelect.value = sender.currentObjectId; 
      }); 
 
      this.loadDefaultDoc(documentViewer, interactiveSelect) 
   } 
 
   loadDefaultDoc = (viewer, interactiveSelect) => { 
      // Load a PDF document 
      const url = "https://demo.leadtools.com/images/pdf/leadtools.pdf"; 
      lt.Document.DocumentFactory.loadFromUri(url, null) 
         .done((doc) => { 
            const ready = () => { 
               viewer.setDocument(doc); 
               const panZoom = lt.Document.Viewer.DocumentViewerCommands.interactivePanZoom; 
               interactiveSelect.value = panZoom; 
               viewer.commands.run(panZoom, null); 
               if(this.callback) 
                  this.callback(viewer); 
            } 
 
            if (doc.isStructureSupported && !doc.structure.isParsed) 
               doc.structure.parse() 
                  .done(ready) 
                  .fail(ViewerInitializer.showServiceError); 
            else 
               ready(); 
         }) 
         .fail(ViewerInitializer.showServiceError); 
   } 
} 
<!doctype html> 
<html lang="en"> 
<title>DocViewer Example | DocumentViewer</title> 
 
<head> 
   <script src="https://code.jquery.com/jquery-2.2.4.min.js" 
      integrity="sha256-BbhdlvQf/xTY9gja0Dq3HiwQF8LaCRTXxZKRutelT44=" crossorigin="anonymous"></script> 
 
   <script src="../LT/Leadtools.js"></script> 
   <script src="../LT/Leadtools.Controls.js"></script> 
   <script src="../LT/Leadtools.Annotations.Engine.js"></script> 
   <script src="../LT/Leadtools.Annotations.Designers.js"></script> 
   <script src="../LT/Leadtools.Annotations.Rendering.Javascript.js"></script> 
   <script src="../LT/Leadtools.Annotations.Automation.js"></script> 
   <script src="../LT/Leadtools.ImageProcessing.Main.js"></script> 
   <script src="../LT/Leadtools.ImageProcessing.Color.js"></script> 
   <script src="../LT/Leadtools.ImageProcessing.Core.js"></script> 
   <script src="../LT/Leadtools.ImageProcessing.Effects.js"></script> 
   <script src="../LT/Leadtools.Document.js"></script> 
   <script src="../LT/Leadtools.Document.Viewer.js"></script> 
   <link rel="stylesheet" type="text/css" href="../css/examples.css"> 
 
   <!-- All demo files are bundled and appended to the window --> 
   <script src="../bundle.js" type="text/javascript"></script> 
</head> 
 
 
<body> 
   <div class="container"> 
      <div class="toolbar"> 
         <div class="vcenter push-right"> 
            <button type="button" id="exampleButton">Run Example</button> 
         </div> 
         <div class="vcenter push-right"> 
            <label for="interactiveSelect">Interactive mode:</label> 
            <select id="interactiveSelect"></select> 
         </div> 
         <div class="vcenter push-right"> 
            <label for="annotationsSelect">Annotations objects:</label> 
            <select id="annotationsSelect"></select> 
         </div> 
         <div id="output" class="vcenter push-right"></div> 
         <div id="serviceStatus" class="vcenter push-right"></div> 
      </div> 
      <div class="docContainer"> 
         <div class="sidepanel" id="thumbnails"></div> 
         <div class="centerpanel" id="viewer"></div> 
         <div class="sidepanel" id="bookmarks"></div> 
      </div> 
   </div> 
</body> 
<script> 
   window.onload = () => { 
      const button = document.getElementById('exampleButton'); 
      button.onclick = () => { 
         const example = new window.examples.ViewExample(); 
         example.run(); 
      } 
   }; 
</script> 
 
</html> 
 /* 
   Remove default body styling. 
   Set the body to flex as a column; 
*/ 
body { 
   margin: 0; 
   display: flex; 
   flex-direction: column; 
} 
 
.container { 
   margin: 10px; 
   width: calc(100% - 20px); 
   height: calc(100vh - 20px); 
} 
 
.toolbar { 
   height: 5%; 
   width: 100%; 
   border-bottom: 2px solid #333; 
   flex-direction: row; 
   display: flex; 
} 
#bookmarks{ 
   overflow: hidden; 
} 
 
.vcenter { 
   margin-top: auto; 
   margin-bottom: auto; 
} 
 
.hcenter{ 
   margin-left: auto; 
   margin-right: auto; 
} 
 
.push-right{ 
   margin-left: 10px; 
} 
 
.docContainer{ 
   height: 95%; 
   width: 100%; 
   display: flex; 
   flex-direction: row; 
} 
 
.sidepanel{ 
   width: 15%; 
   height: 100%; 
} 
 
.centerpanel{ 
   width:100%; 
   height:100%; 
} 
 
 /* Styles for Elements Mode. */ 
 .lt-item, .lt-image-border { 
   /* Box Shadow (view, item, image border) */ 
   box-shadow: #333 2px 2px 5px 1px; 
 } 
 .lt-view,.lt-thumb-item { 
   /* View */ 
   margin: 5px; 
   padding: 5px; 
 } 
 .lt-item { 
   /* Item */ 
   border: 2px solid #6ecaab; 
   background-color: #b2decf; 
   padding: 10px; 
 } 
 .lt-image-border { 
   /* Image Border */ 
   border: 3px solid #444; 
   background-color: white; 
 } 
 .lt-thumb-item { 
   /* Thumbnail Item */ 
   border: 2px solid #6ecaab; 
   background-color: #b2decf; 
 } 
 .lt-thumb-item.lt-thumb-item-selected { 
   /* Selected Thumbnail Item */ 
   border: 2px solid #59b2ba; 
   background-color: #8ce1e1; 
 } 
 .lt-thumb-item-hovered { 
   /* Hovered Thumbnail Item */ 
   border: 2px solid #52b996; 
   background-color: #87c7b1; 
 } 
 .small-modal { 
   max-width: 200px; 
   width: 200px; 
 }
Requirements

Target Platforms

Help Version 22.0.2023.4.18
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© 1991-2023 LEAD Technologies, Inc. All Rights Reserved.

Leadtools.Document.Viewer Assembly
Introduction
Getting Started
Namespaces
Leadtools.Document.Viewer Namespace
Assemblies

Products | Support | Contact Us | Intellectual Property Notices
© 1991-2023 LEAD Technologies, Inc. All Rights Reserved.