enable Method

Summary

Enables an interactive mode in the collection.

Syntax
TypeScript
JavaScript
ImageViewerInteractiveModes.prototype.enable = function( 
   mode 
) 
enable( 
   mode: ImageViewerInteractiveMode 
): void; 

Parameters

mode

The interactive mode to enable. null will disable all items in the collection.

Remarks

This method will iterate through all the item collection and set IsEnabled to false on all items except mode, which will be set to true.

Example

This example adds two interactive modes and a select element to choose between them. Whichever interactive mode is selected becomes enabled while the other mode is disabled. Notice that this is done without rearranging the interactive modes in their collection.

Enable.ts
ImageViewer.ts
Enable.js
ImageViewer.js
Enable.html
import { ImageViewer_Example } from "../ImageViewer"; 
 
export class ImageViewerInteractiveMode_EnableExample { 
   private viewerExample; 
   constructor() { 
      this.viewerExample = new ImageViewer_Example(this.run); 
   } 
 
   private run = (viewer: lt.Controls.ImageViewer) => { 
      // Create a select box 
      const output = document.getElementById("output"); 
      const select = document.createElement("select"); 
      output.appendChild(select); 
 
      // Signal that interactive modes are being updated and should all be stopped. 
      viewer.interactiveModes.beginUpdate(); 
      viewer.interactiveModes.clearItems(); 
 
      // Add two new interactive modes 
      const panZoomMode: lt.Controls.ImageViewerPanZoomInteractiveMode = new lt.Controls.ImageViewerPanZoomInteractiveMode(); 
      viewer.interactiveModes.add(panZoomMode); 
      const magnifyGlassMode: lt.Controls.ImageViewerMagnifyGlassInteractiveMode = new lt.Controls.ImageViewerMagnifyGlassInteractiveMode(); 
      viewer.interactiveModes.add(magnifyGlassMode); 
 
      // Add options for each to be selected 
      for (let i = 0; i < viewer.interactiveModes.count; i++) { 
         const option = document.createElement("option"); 
         option.innerHTML = viewer.interactiveModes.item(i).name; 
         select.appendChild(option); 
      } 
 
      select.addEventListener("change", () => { 
         this.updateEnabled(select.selectedIndex, viewer); 
      }); 
      // Start with panZoom mode 
      select.selectedIndex = 0; 
      this.updateEnabled(select.selectedIndex, viewer); 
 
      // End updates 
      viewer.interactiveModes.endUpdate(); 
   } 
 
   private updateEnabled = (index: number, viewer: lt.Controls.ImageViewer): void => { 
      // The enabled interactive mode will be the only one enabled regardless of position in the list 
      // So if Magnify Glass is enabled and PanZoom is not, only Magnify Glass can do work. 
      viewer.interactiveModes.enable(viewer.interactiveModes.item(index)); 
   } 
} 
export class ImageViewer_Example { 
   // LEADTOOLS ImageViewer to be used with this example 
   protected imageViewer: lt.Controls.ImageViewer = null; 
   // Generic state value used by the examples 
   public timesClicked: number = 0; 
 
   constructor(callback?: (viewer: lt.Controls.ImageViewer) => void) { 
      // Set the LEADTOOLS license. Replace this with your actual license file 
      lt.RasterSupport.setLicenseUri("https://demo.leadtools.com/licenses/js/LEADTOOLSEVAL.txt", "EVAL", null); 
 
      // Create an image viewer inside the imageViewerDiv element 
      const imageViewerDiv = document.getElementById("imageViewerDiv"); 
      const createOptions: lt.Controls.ImageViewerCreateOptions = new lt.Controls.ImageViewerCreateOptions(imageViewerDiv); 
      this.imageViewer = new lt.Controls.ImageViewer(createOptions); 
      this.imageViewer.viewVerticalAlignment = lt.Controls.ControlAlignment.center; 
      this.imageViewer.viewHorizontalAlignment = lt.Controls.ControlAlignment.center; 
      this.imageViewer.autoCreateCanvas = true; 
 
      // Add Pan/Zoom interactive mode 
      // Click and drag to pan, CTRL-Click and drag to zoom in and out 
      this.imageViewer.interactiveModes.add(new lt.Controls.ImageViewerPanZoomInteractiveMode()); 
 
      // Load an image 
      this.imageViewer.imageUrl = "https://demo.leadtools.com/images/jpeg/cannon.jpg"; 
 
      this.imageViewer.zoom(lt.Controls.ControlSizeMode.fit, .9, this.imageViewer.defaultZoomOrigin); 
 
      const exampleButton = document.getElementById("exampleButton"); 
      exampleButton.addEventListener("click", () => { 
         this.timesClicked++; 
         // Run the example 
         if (callback) 
            callback(this.imageViewer); 
      }); 
   } 
} 
import { ImageViewer_Example } from "../ImageViewer"; 
 
export class ImageViewerInteractiveMode_EnableExample { 
   viewerExample; 
   constructor() { 
      this.viewerExample = new ImageViewer_Example(this.run); 
   } 
 
   run = (viewer) => { 
      // Create a select box 
      const output = document.getElementById("output"); 
      const select = document.createElement("select"); 
      output.appendChild(select); 
 
      // Signal that interactive modes are being updated and should all be stopped. 
      viewer.interactiveModes.beginUpdate(); 
      viewer.interactiveModes.clearItems(); 
 
      // Add two new interactive modes 
      const panZoomMode = new lt.Controls.ImageViewerPanZoomInteractiveMode(); 
      viewer.interactiveModes.add(panZoomMode); 
      const magnifyGlassMode = new lt.Controls.ImageViewerMagnifyGlassInteractiveMode(); 
      viewer.interactiveModes.add(magnifyGlassMode); 
 
      // Add options for each to be selected 
      for (let i = 0; i < viewer.interactiveModes.count; i++) { 
         const option = document.createElement("option"); 
         option.innerHTML = viewer.interactiveModes.item(i).name; 
         select.appendChild(option); 
      } 
 
      select.addEventListener("change", () => { 
         this.updateEnabled(select.selectedIndex, viewer); 
      }); 
      // Start with panZoom mode 
      select.selectedIndex = 0; 
      this.updateEnabled(select.selectedIndex, viewer); 
 
      // End updates 
      viewer.interactiveModes.endUpdate(); 
   } 
 
   updateEnabled = (index, viewer) => { 
      // The enabled interactive mode will be the only one enabled regardless of position in the list 
      // So if Magnify Glass is enabled and PanZoom is not, only Magnify Glass can do work. 
      viewer.interactiveModes.enable(viewer.interactiveModes.item(index)); 
   } 
} 
export class ImageViewer_Example { 
   // LEADTOOLS ImageViewer to be used with this example 
   imageViewer = null; 
   // Generic state value used by the examples 
   timesClicked = 0; 
 
   constructor(callback) { 
      // Set the LEADTOOLS license. Replace this with your actual license file 
      lt.RasterSupport.setLicenseUri("https://demo.leadtools.com/licenses/js/LEADTOOLSEVAL.txt", "EVAL", null); 
 
      // Create an image viewer inside the imageViewerDiv element 
      const imageViewerDiv = document.getElementById("imageViewerDiv"); 
      const createOptions = new lt.Controls.ImageViewerCreateOptions(imageViewerDiv); 
      this.imageViewer = new lt.Controls.ImageViewer(createOptions); 
      this.imageViewer.viewVerticalAlignment = lt.Controls.ControlAlignment.center; 
      this.imageViewer.viewHorizontalAlignment = lt.Controls.ControlAlignment.center; 
      this.imageViewer.autoCreateCanvas = true; 
 
      // Add Pan/Zoom interactive mode 
      // Click and drag to pan, CTRL-Click and drag to zoom in and out 
      this.imageViewer.interactiveModes.add(new lt.Controls.ImageViewerPanZoomInteractiveMode()); 
 
      // Load an image 
      this.imageViewer.imageUrl = "https://demo.leadtools.com/images/jpeg/cannon.jpg"; 
 
      this.imageViewer.zoom(lt.Controls.ControlSizeMode.fit, .9, this.imageViewer.defaultZoomOrigin); 
 
      const exampleButton = document.getElementById("exampleButton"); 
      exampleButton.addEventListener("click", () => { 
         this.timesClicked++; 
         // Run the example 
         if (callback) 
            callback(this.imageViewer); 
      }); 
   } 
} 
<!doctype html> 
<html lang="en"> 
<title>Controls Example | Enable</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> 
   <style> 
      body { 
         font-family: 'Segoe UI', sans-serif; 
      } 
 
      #imageViewerDiv { 
         border: 1px solid #888; 
         width: 500px; 
         height: 500px; 
         background-color: #eee; 
      } 
   </style> 
 
   <!-- All demo files are bundled and appended to the window --> 
   <script src="../../bundle.js" type="text/javascript"></script> 
</head> 
 
<body> 
   <p>Press and drag on the image to pan.</p> 
   <p>Hold down the control key and press and drag on the image or pinch with two fingers to zoom in and out.</p> 
   <div> 
      <button type="button" id="exampleButton">Run Example</button> 
   </div> 
   <div id="imageViewerDiv"></div> 
   <div id="output"></div> 
</body> 
 
<script> 
   window.onload = () => { 
      const example = new window.examples.InteractiveMode.Enable(); 
 
   }; 
</script> 
</html> 
Requirements

Target Platforms

Help Version 22.0.2021.9.24
Products | Support | Contact Us | Intellectual Property Notices
© 1991-2022 LEAD Technologies, Inc. All Rights Reserved.

Leadtools.Controls Assembly
Products | Support | Contact Us | Intellectual Property Notices
© 1991-2022 LEAD Technologies, Inc. All Rights Reserved.