Determines how the control displays the image and the automatic adjustments of the display rectangles.
lt.Controls.ControlSizeMode = {
none: 0,
actualSize: 1,
fit: 2,
fitAlways: 3,
fitWidth: 4,
fitHeight: 5,
stretch: 6
}
lt.Controls.ControlSizeMode = {
none: 0,
actualSize: 1,
fit: 2,
fitAlways: 3,
fitWidth: 4,
fitHeight: 5,
stretch: 6
}
0 |
None |
(0) No special sizing |
1 |
ActualSize |
(1) Use the image actual size |
2 |
Fit |
(2) Fit the image into the viewing area while maintaining the aspect ratio. If the image size is smaller than the viewing area, no resizing is done. |
3 |
FitAlways |
(3) Always fit the image into the viewing area while maintaining the aspect ratio even if the image size is smaller than the viewing area (in which case, the image will be scaled up). |
4 |
FitWidth |
(4) Fit the image width to be the size of the width of the viewing area while maintaining the aspect ratio. |
5 |
FitHeight |
(5) Fit the image height to be the size of the height of the viewing area while maintaining the aspect ratio. |
6 |
Stretch |
(6) Fit the image to fill the viewing area. Aspect ratio might not be maintained. |
ControlSizeMode is used by the ImageViewer.Zoom and ImageViewerItem.Zoom methods.
import { ImageViewer_Example } from "../ImageViewer";
export class ImageViewer_ZoomExample {
private viewerExample;
constructor() {
this.viewerExample = new ImageViewer_Example(this.run);
}
private run = (viewer: lt.Controls.ImageViewer) => {
// Ratio to use when the user zooms in or out. Change this if another value is needed,
// for example, 2.0 will zoom the viewer in by 200% and out by 50% each time
const _zoomRatio: number = 1.2;
const updateZoomValueFromView = () => {
// Get the current scale factor from the viewer and set it in the zoom combo box
const percentage = viewer.scaleFactor * 100.0;
titleOption.innerHTML = percentage.toFixed(2) + "%";
zoomSelect.selectedIndex = 0;
};
const output = document.getElementById("output");
// Add a combo box for the zoom values
const zoomSelect = document.createElement("select");
const zoomValues: string[] = ["10%", "25%", "50%", "75%", "100%", "125%", "200%", "400%", "800%",
"1600%", "2400%", "3200%", "6400%", "Actual Size", "Fit Page", "Fit Width", "Fit Height"];
// Add a title option to show the current zoom
const titleOption = document.createElement("option");
titleOption.disabled = true;
titleOption.innerHTML = "N/A";
zoomSelect.appendChild(titleOption);
// Add default zoom values
for (let i = 0; i < zoomValues.length; i++) {
const option = document.createElement("option");
option.textContent = zoomValues[i];
zoomSelect.appendChild(option);
}
zoomSelect.selectedIndex = 0;
output.appendChild(zoomSelect);
// For zoom in button, use current ScaleFactor multiplied by the ratio
const zoomInButton = document.createElement("button");
zoomInButton.innerHTML = "+"; // +
zoomInButton.addEventListener("click", () => {
viewer.zoom(lt.Controls.ControlSizeMode.none, viewer.scaleFactor * _zoomRatio, viewer.defaultZoomOrigin);
});
output.appendChild(zoomInButton);
// For zoom out button, use current ScaleFactor divided by the ratio
const zoomOutButton = document.createElement("button");
zoomOutButton.innerHTML = "-"; // -
zoomOutButton.addEventListener("click", () => {
viewer.zoom(lt.Controls.ControlSizeMode.none, viewer.scaleFactor / _zoomRatio, viewer.defaultZoomOrigin);
});
output.appendChild(zoomOutButton);
zoomSelect.addEventListener("change", () => {
// Get the value from the combo box
const value: string = zoomSelect.value.trim();
let isPercentage: boolean;
let sizeMode: lt.Controls.ControlSizeMode;
switch (value) {
case "Actual Size":
sizeMode = lt.Controls.ControlSizeMode.actualSize;
isPercentage = false;
break;
case "Fit Page":
sizeMode = lt.Controls.ControlSizeMode.fitAlways;
isPercentage = false;
break;
case "Fit Width":
sizeMode = lt.Controls.ControlSizeMode.fitWidth;
isPercentage = false;
break;
case "Fit Height":
sizeMode = lt.Controls.ControlSizeMode.fitHeight;
isPercentage = false;
break;
default:
isPercentage = true;
break;
}
if (!isPercentage) {
viewer.zoom(sizeMode, 1, viewer.defaultZoomOrigin);
}
else if (value) {
// A percentage, use it
const percentage: string = value.substring(0, value.length - 1);
viewer.zoom(lt.Controls.ControlSizeMode.none, parseFloat(percentage) / 100.0, viewer.defaultZoomOrigin);
}
});
// Also update the value from the viewer when the transform changed, this happens if the user selects a fit mode,
// such as fit width or fit page. The viewer will change the scale factor accordingly.
// This also takes care of Pan/Zoom interactive mode updating the scale fatcor.
viewer.transformChanged.add((sender, e) => {
updateZoomValueFromView();
});
// Get the value from the viewer into the combo box
updateZoomValueFromView();
}
}
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 ImageViewer_ZoomExample {
viewerExample;
constructor() {
this.viewerExample = new ImageViewer_Example(this.run);
}
run = (viewer) => {
// Ratio to use when the user zooms in or out. Change this if another value is needed,
// for example, 2.0 will zoom the viewer in by 200% and out by 50% each time
const _zoomRatio = 1.2;
const updateZoomValueFromView = () => {
// Get the current scale factor from the viewer and set it in the zoom combo box
const percentage = viewer.scaleFactor * 100.0;
titleOption.innerHTML = percentage.toFixed(2) + "%";
zoomSelect.selectedIndex = 0;
};
const output = document.getElementById("output");
// Add a combo box for the zoom values
const zoomSelect = document.createElement("select");
const zoomValues = ["10%", "25%", "50%", "75%", "100%", "125%", "200%", "400%", "800%",
"1600%", "2400%", "3200%", "6400%", "Actual Size", "Fit Page", "Fit Width", "Fit Height"];
// Add a title option to show the current zoom
const titleOption = document.createElement("option");
titleOption.disabled = true;
titleOption.innerHTML = "N/A";
zoomSelect.appendChild(titleOption);
// Add default zoom values
for (let i = 0; i < zoomValues.length; i++) {
const option = document.createElement("option");
option.textContent = zoomValues[i];
zoomSelect.appendChild(option);
}
zoomSelect.selectedIndex = 0;
output.appendChild(zoomSelect);
// For zoom in button, use current ScaleFactor multiplied by the ratio
const zoomInButton = document.createElement("button");
zoomInButton.innerHTML = "+"; // +
zoomInButton.addEventListener("click", () => {
viewer.zoom(lt.Controls.ControlSizeMode.none, viewer.scaleFactor * _zoomRatio, viewer.defaultZoomOrigin);
});
output.appendChild(zoomInButton);
// For zoom out button, use current ScaleFactor divided by the ratio
const zoomOutButton = document.createElement("button");
zoomOutButton.innerHTML = "-"; // -
zoomOutButton.addEventListener("click", () => {
viewer.zoom(lt.Controls.ControlSizeMode.none, viewer.scaleFactor / _zoomRatio, viewer.defaultZoomOrigin);
});
output.appendChild(zoomOutButton);
zoomSelect.addEventListener("change", () => {
// Get the value from the combo box
const value = zoomSelect.value.trim();
let isPercentage;
let sizeMode;
switch (value) {
case "Actual Size":
sizeMode = lt.Controls.ControlSizeMode.actualSize;
isPercentage = false;
break;
case "Fit Page":
sizeMode = lt.Controls.ControlSizeMode.fitAlways;
isPercentage = false;
break;
case "Fit Width":
sizeMode = lt.Controls.ControlSizeMode.fitWidth;
isPercentage = false;
break;
case "Fit Height":
sizeMode = lt.Controls.ControlSizeMode.fitHeight;
isPercentage = false;
break;
default:
isPercentage = true;
break;
}
if (!isPercentage) {
viewer.zoom(sizeMode, 1, viewer.defaultZoomOrigin);
}
else if (value) {
// A percentage, use it
const percentage = value.substring(0, value.length - 1);
viewer.zoom(lt.Controls.ControlSizeMode.none, parseFloat(percentage) / 100.0, viewer.defaultZoomOrigin);
}
});
// Also update the value from the viewer when the transform changed, this happens if the user selects a fit mode,
// such as fit width or fit page. The viewer will change the scale factor accordingly.
// This also takes care of Pan/Zoom interactive mode updating the scale fatcor.
viewer.transformChanged.add((sender, e) => {
updateZoomValueFromView();
});
// Get the value from the viewer into the combo box
updateZoomValueFromView();
}
}
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 | Zoom</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.ImageViewer.Zoom();
};
</script>
</html>
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