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 desirable 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"
     clip: true
 }

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

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

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

See also Image example.

These properties hold the size of the image that is actually painted. In most cases it is the same as width and height, but when using a fillMode PreserveAspectFit or fillMode PreserveAspectCrop paintedWidth or paintedHeight can be smaller or larger than width and height of the Image element.

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.

See also QDeclarativeImageProvider.

This property holds the actual width and height of the loaded image.

Unlike the width and height properties, which scale the painting of the image, this property sets the actual number of pixels stored for the loaded image so that large images do not use more memory than necessary. For example, this ensures the image in memory is no larger than 1024x1024 pixels, regardless of the Image's width and height values:

 Rectangle {
     width: ...
     height: ...

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

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 causes the image source to be reloaded, potentially even from the network, if it is not in the disk cache.

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 ? 'Loaded' : 'Not loaded' }

See also progress.