voltmx.image Namespace

The following constants are used to specify the format of an Image widget’s bitmap.

Creates an Image. This function has three overloads.

Syntax

voltmx.image.createImage(rawBytes);

voltmx.image.createImage(  
    bundledImageFileName);

voltmx.image.createImage(  
    Image);

Input Parameters

Any one of the following parameters can be passed in the function.

Example

var imgBright = voltmx.image.createImage(this.imageBytes);

Return Values

This function returns an image object with its associated bitmap.

Remarks

If your app creates an Image from a RawBytes object, it should not make copies of the Image by creating it again from the initial RawBytes object. Creating multiple Image objects from the same RawBytes object results in undefined behavior. Rather than copying the RawBytes object into multiple Image objects, your app can make further copies by calling this function and passing it the Image object created in the first call to this function.

If your app creates an image from a bundled file, the file specified by the bundledImageFileName parameter can be in the GIF, an animated GIF, a JPEG, or PNG file format.

Platform Availability

Available on iOS and Android.

Creates an Image by taking a snapshot of a widget.

Syntax

voltmx.image.createImageFromSnapShot(widget);

Input Parameters

Example

var imgBlurBg = voltmx.image.createImageFromSnapShot(frmHome.widget1);

Return Values

This function returns an Image that contains a snapshot of the widget passed in through the widget parameter.

Remarks

When the image source is snapshot, the source is device screen, which is having twice the density of actual image, so the scale factor of image will be twice the image size because of the retina display of device.

Platform Availability

Available on iOS and Android.

Crops the bitmap in an Image object and returns it as an array of tiles.

Syntax

voltmx.image.cropImageInTiles(image,xTiles,yTiles);

Input Parameters

Example

var img = voltmx.image.createImage(rawB); // Here rawB is the rawBytes of the image 
var imageArray = voltmx.image.cropImageInTiles(img, 10, 20);

Return Values

This function returns an array of Image widgets that were created from tiles of the bitmap in the Image object in the image parameter.

Platform Availability

Available on iOS and Android.

Crops portions of an Image widget’s bitmap to a set of rectangles and returns an array of Image widgets containg the cropped bitmaps.

Syntax

voltmx.image.cropImageInTilesForRects(  
    image,  
    \[ \[x,y,w,h\],\[x1,y1,w1,h1\],... \]);

Parameters

Example

function getImageFromLocalStorage(imageName) {
    var img = voltmx.image.createImage(imageName);
    return img;
}

/*var clippingRects = [
        [10, 12, 50, 100],
        [30, 45, 10, 200],
        [300, 100, 200, 10]];*/
function cropImageToTilesFromRects(clippingRects, localImage, FormToaddImage) {
    try {
        var img = getImageFromLocalStorage(localImage);
        var imageArray = voltmx.image.cropImageInTilesForRects(img, clippingRects);
        for (var j = 0; j < imageArray.length; j++) {
            var imgW = createImageWidget(imageArray[j]);
            FormToaddImage.add(imgW);
        }
        FormToaddImage.forceLayout();
    } catch (err) {
        alert(err);
    }
}

Return Values

This function returns an array of Image widgets that contain the bitmap information from the bitmap in the Image widget passed through the image parameter.

Remarks

This method iterates through an array of rectangles and uses each rectangle to obtain a cropped version of the bitmap associated with the Image widget in the image parameter. The original bitmap is not changed. It then creates an Image widget from each cropped bitmap and collects then into an array of Image widgets. It then returns the array of Image widgets.

Platform Availability

Available on iOS and Android.