Class AsyncImageLoader

Definition

Namespace:

Tizen.NUI

Assembly:

Tizen.NUI.dll

Loader class to loading image asynchronously. Request to load image, and get result as PixelData or PixelBuffer

public class AsyncImageLoader : BaseHandle, IDynamicResourceHandler, INameScope, System.IDisposable

Inheritance

object

BindableObject

Element

BaseHandle

AsyncImageLoader

Implements

IDynamicResourceHandler

INameScope

System.IDisposable

Remarks

Request image loading by Load(). Each Load API return their specific id, which can be used at ImageLoaded / PixelBufferLoaded signal, or Cancel.

We can create multiple loader. But load task id are not be shared. All API should be called at main thread.

Examples

Here is some demo codes to get color picking by Palette

AsyncImageLoader loader = new AsyncImageLoader();
loader.PixelBufferLoaded += OnPixelBufferLoaded;
uint taskId = loader.Load("some_image.jpg");
...
private async void OnPixelBufferLoadedWithColorPalette(object o, AsyncImageLoader.PixelBufferLoadedEventArgs e)
{
  if (taskId == e.LoadingTaskId)
  {
    PixelBuffer pixelBuffer = e.PixelBuffers[0];

    // Copy the pixelData if we need to color picking.
    PixelData pixelData = pixelBuffer.CreatePixelData();
    ImageUrl imageUrl = pixelData.GenerateUrl();
    imageView.ResourceUrl = imageUrl.ToString();

    // We need to create new class due to the PixelBuffer become invalidated after callback finished.
    var task = Palette.GenerateAsync(new PixelBuffer(pixelBuffer));
    var palette = await task;

    // Get palette result.
    paletteSwatch = palette.GetDominantSwatch();
  }
}
...
if (paletteSwatch != null)
{
  swatchInfo.BackgroundColor = paletteSwatch.GetRgb();
  titleLabel.TextColor = paletteSwatch.GetTitleTextColor();
  bodyLabel.TextColor = paletteSwatch.GetBodyTextColor();
}

Constructors

AsyncImageLoader()

Declaration

public AsyncImageLoader()

Remarks

Request image loading by Load(). Each Load API return their specific id, which can be used at ImageLoaded / PixelBufferLoaded signal, or Cancel.

We can create multiple loader. But load task id are not be shared. All API should be called at main thread.

Examples

Here is some demo codes to get color picking by Palette

AsyncImageLoader loader = new AsyncImageLoader();
loader.PixelBufferLoaded += OnPixelBufferLoaded;
uint taskId = loader.Load("some_image.jpg");
...
private async void OnPixelBufferLoadedWithColorPalette(object o, AsyncImageLoader.PixelBufferLoadedEventArgs e)
{
  if (taskId == e.LoadingTaskId)
  {
    PixelBuffer pixelBuffer = e.PixelBuffers[0];

    // Copy the pixelData if we need to color picking.
    PixelData pixelData = pixelBuffer.CreatePixelData();
    ImageUrl imageUrl = pixelData.GenerateUrl();
    imageView.ResourceUrl = imageUrl.ToString();

    // We need to create new class due to the PixelBuffer become invalidated after callback finished.
    var task = Palette.GenerateAsync(new PixelBuffer(pixelBuffer));
    var palette = await task;

    // Get palette result.
    paletteSwatch = palette.GetDominantSwatch();
  }
}
...
if (paletteSwatch != null)
{
  swatchInfo.BackgroundColor = paletteSwatch.GetRgb();
  titleLabel.TextColor = paletteSwatch.GetTitleTextColor();
  bodyLabel.TextColor = paletteSwatch.GetBodyTextColor();
}

Methods

Cancel(uint)

Declaration

public bool Cancel(uint loadingTaskId)

Parameters

Type	Name	Description
uint	loadingTaskId

Returns

Type	Description
bool

Remarks

Request image loading by Load(). Each Load API return their specific id, which can be used at ImageLoaded / PixelBufferLoaded signal, or Cancel.

We can create multiple loader. But load task id are not be shared. All API should be called at main thread.

Examples

Here is some demo codes to get color picking by Palette

AsyncImageLoader loader = new AsyncImageLoader();
loader.PixelBufferLoaded += OnPixelBufferLoaded;
uint taskId = loader.Load("some_image.jpg");
...
private async void OnPixelBufferLoadedWithColorPalette(object o, AsyncImageLoader.PixelBufferLoadedEventArgs e)
{
  if (taskId == e.LoadingTaskId)
  {
    PixelBuffer pixelBuffer = e.PixelBuffers[0];

    // Copy the pixelData if we need to color picking.
    PixelData pixelData = pixelBuffer.CreatePixelData();
    ImageUrl imageUrl = pixelData.GenerateUrl();
    imageView.ResourceUrl = imageUrl.ToString();

    // We need to create new class due to the PixelBuffer become invalidated after callback finished.
    var task = Palette.GenerateAsync(new PixelBuffer(pixelBuffer));
    var palette = await task;

    // Get palette result.
    paletteSwatch = palette.GetDominantSwatch();
  }
}
...
if (paletteSwatch != null)
{
  swatchInfo.BackgroundColor = paletteSwatch.GetRgb();
  titleLabel.TextColor = paletteSwatch.GetTitleTextColor();
  bodyLabel.TextColor = paletteSwatch.GetBodyTextColor();
}

CancelAll()

Declaration

public void CancelAll()

Remarks

Request image loading by Load(). Each Load API return their specific id, which can be used at ImageLoaded / PixelBufferLoaded signal, or Cancel.

We can create multiple loader. But load task id are not be shared. All API should be called at main thread.

Examples

Here is some demo codes to get color picking by Palette

AsyncImageLoader loader = new AsyncImageLoader();
loader.PixelBufferLoaded += OnPixelBufferLoaded;
uint taskId = loader.Load("some_image.jpg");
...
private async void OnPixelBufferLoadedWithColorPalette(object o, AsyncImageLoader.PixelBufferLoadedEventArgs e)
{
  if (taskId == e.LoadingTaskId)
  {
    PixelBuffer pixelBuffer = e.PixelBuffers[0];

    // Copy the pixelData if we need to color picking.
    PixelData pixelData = pixelBuffer.CreatePixelData();
    ImageUrl imageUrl = pixelData.GenerateUrl();
    imageView.ResourceUrl = imageUrl.ToString();

    // We need to create new class due to the PixelBuffer become invalidated after callback finished.
    var task = Palette.GenerateAsync(new PixelBuffer(pixelBuffer));
    var palette = await task;

    // Get palette result.
    paletteSwatch = palette.GetDominantSwatch();
  }
}
...
if (paletteSwatch != null)
{
  swatchInfo.BackgroundColor = paletteSwatch.GetRgb();
  titleLabel.TextColor = paletteSwatch.GetTitleTextColor();
  bodyLabel.TextColor = paletteSwatch.GetBodyTextColor();
}

Dispose(DisposeTypes)

You can override it to clean-up your own resources

Declaration

protected override void Dispose(DisposeTypes type)

Parameters

Type	Name	Description
DisposeTypes	type	DisposeTypes

Overrides

BaseHandle.Dispose(DisposeTypes)

Remarks

Request image loading by Load(). Each Load API return their specific id, which can be used at ImageLoaded / PixelBufferLoaded signal, or Cancel.

We can create multiple loader. But load task id are not be shared. All API should be called at main thread.

Load(string, uint, uint, FittingModeType, SamplingModeType, bool)

Declaration

public uint Load(string url, uint desiredWidth, uint desiredHeight, FittingModeType fittingMode, SamplingModeType samplingMode, bool orientationCorrection)

Parameters

Type	Name	Description
string	url
uint	desiredWidth
uint	desiredHeight
FittingModeType	fittingMode
SamplingModeType	samplingMode
bool	orientationCorrection

Returns

Type	Description
uint

Remarks

Request image loading by Load(). Each Load API return their specific id, which can be used at ImageLoaded / PixelBufferLoaded signal, or Cancel.

We can create multiple loader. But load task id are not be shared. All API should be called at main thread.

Examples

Here is some demo codes to get color picking by Palette

AsyncImageLoader loader = new AsyncImageLoader();
loader.PixelBufferLoaded += OnPixelBufferLoaded;
uint taskId = loader.Load("some_image.jpg");
...
private async void OnPixelBufferLoadedWithColorPalette(object o, AsyncImageLoader.PixelBufferLoadedEventArgs e)
{
  if (taskId == e.LoadingTaskId)
  {
    PixelBuffer pixelBuffer = e.PixelBuffers[0];

    // Copy the pixelData if we need to color picking.
    PixelData pixelData = pixelBuffer.CreatePixelData();
    ImageUrl imageUrl = pixelData.GenerateUrl();
    imageView.ResourceUrl = imageUrl.ToString();

    // We need to create new class due to the PixelBuffer become invalidated after callback finished.
    var task = Palette.GenerateAsync(new PixelBuffer(pixelBuffer));
    var palette = await task;

    // Get palette result.
    paletteSwatch = palette.GetDominantSwatch();
  }
}
...
if (paletteSwatch != null)
{
  swatchInfo.BackgroundColor = paletteSwatch.GetRgb();
  titleLabel.TextColor = paletteSwatch.GetTitleTextColor();
  bodyLabel.TextColor = paletteSwatch.GetBodyTextColor();
}

Load(string, uint, uint)

Declaration

public uint Load(string url, uint desiredWidth, uint desiredHeight)

Parameters

Type	Name	Description
string	url
uint	desiredWidth
uint	desiredHeight

Returns

Type	Description
uint

Remarks

Request image loading by Load(). Each Load API return their specific id, which can be used at ImageLoaded / PixelBufferLoaded signal, or Cancel.

We can create multiple loader. But load task id are not be shared. All API should be called at main thread.

Examples

Here is some demo codes to get color picking by Palette

AsyncImageLoader loader = new AsyncImageLoader();
loader.PixelBufferLoaded += OnPixelBufferLoaded;
uint taskId = loader.Load("some_image.jpg");
...
private async void OnPixelBufferLoadedWithColorPalette(object o, AsyncImageLoader.PixelBufferLoadedEventArgs e)
{
  if (taskId == e.LoadingTaskId)
  {
    PixelBuffer pixelBuffer = e.PixelBuffers[0];

    // Copy the pixelData if we need to color picking.
    PixelData pixelData = pixelBuffer.CreatePixelData();
    ImageUrl imageUrl = pixelData.GenerateUrl();
    imageView.ResourceUrl = imageUrl.ToString();

    // We need to create new class due to the PixelBuffer become invalidated after callback finished.
    var task = Palette.GenerateAsync(new PixelBuffer(pixelBuffer));
    var palette = await task;

    // Get palette result.
    paletteSwatch = palette.GetDominantSwatch();
  }
}
...
if (paletteSwatch != null)
{
  swatchInfo.BackgroundColor = paletteSwatch.GetRgb();
  titleLabel.TextColor = paletteSwatch.GetTitleTextColor();
  bodyLabel.TextColor = paletteSwatch.GetBodyTextColor();
}

Load(string)

Declaration

public uint Load(string url)

Parameters

Type	Name	Description
string	url

Returns

Type	Description
uint

Remarks

Request image loading by Load(). Each Load API return their specific id, which can be used at ImageLoaded / PixelBufferLoaded signal, or Cancel.

We can create multiple loader. But load task id are not be shared. All API should be called at main thread.

Examples

Here is some demo codes to get color picking by Palette

AsyncImageLoader loader = new AsyncImageLoader();
loader.PixelBufferLoaded += OnPixelBufferLoaded;
uint taskId = loader.Load("some_image.jpg");
...
private async void OnPixelBufferLoadedWithColorPalette(object o, AsyncImageLoader.PixelBufferLoadedEventArgs e)
{
  if (taskId == e.LoadingTaskId)
  {
    PixelBuffer pixelBuffer = e.PixelBuffers[0];

    // Copy the pixelData if we need to color picking.
    PixelData pixelData = pixelBuffer.CreatePixelData();
    ImageUrl imageUrl = pixelData.GenerateUrl();
    imageView.ResourceUrl = imageUrl.ToString();

    // We need to create new class due to the PixelBuffer become invalidated after callback finished.
    var task = Palette.GenerateAsync(new PixelBuffer(pixelBuffer));
    var palette = await task;

    // Get palette result.
    paletteSwatch = palette.GetDominantSwatch();
  }
}
...
if (paletteSwatch != null)
{
  swatchInfo.BackgroundColor = paletteSwatch.GetRgb();
  titleLabel.TextColor = paletteSwatch.GetTitleTextColor();
  bodyLabel.TextColor = paletteSwatch.GetBodyTextColor();
}

ReleaseSwigCPtr(HandleRef)

Declaration

protected override void ReleaseSwigCPtr(System.Runtime.InteropServices.HandleRef swigCPtr)

Parameters

Type	Name	Description
System.Runtime.InteropServices.HandleRef	swigCPtr

Overrides

BaseHandle.ReleaseSwigCPtr(System.Runtime.InteropServices.HandleRef)

Remarks

Request image loading by Load(). Each Load API return their specific id, which can be used at ImageLoaded / PixelBufferLoaded signal, or Cancel.

We can create multiple loader. But load task id are not be shared. All API should be called at main thread.

Examples

Here is some demo codes to get color picking by Palette

AsyncImageLoader loader = new AsyncImageLoader();
loader.PixelBufferLoaded += OnPixelBufferLoaded;
uint taskId = loader.Load("some_image.jpg");
...
private async void OnPixelBufferLoadedWithColorPalette(object o, AsyncImageLoader.PixelBufferLoadedEventArgs e)
{
  if (taskId == e.LoadingTaskId)
  {
    PixelBuffer pixelBuffer = e.PixelBuffers[0];

    // Copy the pixelData if we need to color picking.
    PixelData pixelData = pixelBuffer.CreatePixelData();
    ImageUrl imageUrl = pixelData.GenerateUrl();
    imageView.ResourceUrl = imageUrl.ToString();

    // We need to create new class due to the PixelBuffer become invalidated after callback finished.
    var task = Palette.GenerateAsync(new PixelBuffer(pixelBuffer));
    var palette = await task;

    // Get palette result.
    paletteSwatch = palette.GetDominantSwatch();
  }
}
...
if (paletteSwatch != null)
{
  swatchInfo.BackgroundColor = paletteSwatch.GetRgb();
  titleLabel.TextColor = paletteSwatch.GetTitleTextColor();
  bodyLabel.TextColor = paletteSwatch.GetBodyTextColor();
}

Events

ImageLoaded

Event when pixel data are loaded. null or empty PixelData if load failed.

Declaration

public event EventHandler<AsyncImageLoader.ImageLoadedEventArgs> ImageLoaded

Event Type

Type	Description
EventHandler<><ImageLoadedEventArgs>

Remarks

We cannot use both ImageLoaded and PixelBufferLoaded events. If we use PixelBufferLoaded, ImageLoaded will be ignored.

PixelBufferLoaded

Event when pixel buffers are loaded. null or empty PixelBuffer list if load failed.

Declaration

public event EventHandler<AsyncImageLoader.PixelBufferLoadedEventArgs> PixelBufferLoaded

Event Type

Type	Description
EventHandler<><PixelBufferLoadedEventArgs>

Remarks

We cannot use both ImageLoaded and PixelBufferLoaded events. If we use PixelBufferLoaded, ImageLoaded will be ignored.

Implements

IDynamicResourceHandler

INameScope

System.IDisposable

Extension Methods

EXamlExtensions.LoadFromEXamlByRelativePath<T>(T, string)

Extensions.LoadFromXaml<TXaml>(TXaml, string)

Extensions.LoadFromXaml<TXaml>(TXaml, Type)

Extensions.LoadFromXamlFile<TXaml>(TXaml, string)

BindableObjectExtensions.SetBinding(BindableObject, BindableProperty, string, BindingMode, IValueConverter, string)

NameScopeExtensions.FindByName<T>(Element, string)