QML Image Element

Specifies that images on the local filesystem should be loaded asynchronously in a separate thread. The default value is false, causing the user interface thread to block while the image is loaded. Setting asynchronous to true is useful where maintaining a responsive user interface is more desireable than having images immediately visible.

Note that this property is only valid for images read from the local filesystem. Images loaded via a network resource (e.g. HTTP) are always loaded asynchonously.

Set this property to define what happens when the image set for the item is smaller than the size of the item.

• Image.Stretch - the image is scaled to fit
• Image.PreserveAspectFit - the image is scaled uniformly to fit without cropping
• Image.PreserveAspectCrop - the image is scaled uniformly to fill, cropping if necessary
• Image.Tile - the image is duplicated horizontally and vertically
• Image.TileVertically - the image is stretched horizontally and tiled vertically
• Image.TileHorizontally - the image is stretched vertically and tiled horizontally

 Image {
     width: 130; height: 100
     smooth: true
     source: "qtlogo.png"
 }

 Image {
     width: 130; height: 100
     fillMode: Image.PreserveAspectFit
     smooth: true
     source: "qtlogo.png"
 }

 Image {
     width: 130; height: 100
     fillMode: Image.PreserveAspectCrop
     smooth: true
     source: "qtlogo.png"
 }

 Image {
     width: 120; height: 120
     fillMode: Image.Tile
     source: "qtlogo.png"
 }

 Image {
     width: 120; height: 120
     fillMode: Image.TileVertically
     source: "qtlogo.png"
 }

 Image {
     width: 120; height: 120
     fillMode: Image.TileHorizontally
     source: "qtlogo.png"
 }

This property holds the QPixmap image to display.

This is useful for displaying images provided by a C++ implementation, for example, a model may provide a data role of type QPixmap.

This property holds the progress of image loading, from 0.0 (nothing loaded) to 1.0 (finished).

See also status.

Set this property if you want the image to be smoothly filtered when scaled or transformed. Smooth filtering gives better visual quality, but is slower. If the image is displayed at its natural size, this property has no visual or performance effect.

Note: Generally scaling artifacts are only visible if the image is stationary on the screen. A common pattern when animating an image is to disable smooth filtering at the beginning of the animation and reenable it at the conclusion.

Image can handle any image format supported by Qt, loaded from any URL scheme supported by Qt.

The URL may be absolute, or relative to the URL of the component.

This property holds the size of the loaded image, in pixels.

This is used to control the storage used by a loaded image. Unlike the width and height properties, which scale the painting of the image, this property affects the number of pixels stored.

If the image's actual size is larger than the sourceSize, the image is scaled down. If only one dimension of the size is set to greater than 0, the other dimension is set in proportion to preserve the source image's aspect ratio. (The fillMode is independent of this.)

If the source is an instrinsically scalable image (eg. SVG), this property determines the size of the loaded image regardless of intrinsic size. Avoid changing this property dynamically; rendering an SVG is slow compared to an image.

If the source is a non-scalable image (eg. JPEG), the loaded image will be no greater than this property specifies. For some formats (currently only JPEG), the whole image will never actually be loaded into memory.

Note: Changing this property dynamically will lead to the image source being reloaded, potentially even from the network if it is not in the disk cache.

Here is an example that ensures the size of the image in memory is no larger than 1024x1024 pixels, regardless of the size of the Image element.

 Image {
    anchors.fill: parent
    source: "images/reallyBigImage.jpg"
    sourceSize.width: 1024
    sourceSize.height: 1024
 }

The example below ensures the memory used by the image is no more than necessary to display the image at the size of the Image element. Of course if the Image element is resized a costly reload will be required, so use this technique only when the Image size is fixed.

 Image {
    anchors.fill: parent
    source: "images/reallyBigImage.jpg"
    sourceSize.width: width
    sourceSize.height: height
 }

This property holds the status of image loading. It can be one of:

• Image.Null - no image has been set
• Image.Ready - the image has been loaded
• Image.Loading - the image is currently being loaded
• Image.Error - an error occurred while loading the image

Use this status to provide an update or respond to the status change in some way. For example, you could:

Trigger a state change:

 State { name: 'loaded'; when: image.status = Image.Ready }

Implement an onStatusChanged signal handler:

 Image {
     id: image
     onStatusChanged: if (image.status == Image.Ready) console.log('Loaded')
 }

Bind to the status value:

 Text { text: image.status != Image.Ready ? 'Not Loaded' : 'Loaded' }

See also progress.