TabList中的setIconElement 这个怎么使用？

可参考如下代码：

public  void  setTabIcon(TabList.Tab tab) {

   //ResourceTable.Media_icon 为项目图片资源ID，通过resourceID获取PixelMap对象

    Optional<PixelMap> pixelMapOptional = createPixelMapByResId(ResourceTable.Media_icon);

    //创建PixelMapElement对象

    PixelMapElement bitmapDrawable = new PixelMapElement(pixelMapOptional.get());

    //给tab设置IconElement

    tab.setIconElement(bitmapDrawable);

}

public  Optional<PixelMap> createPixelMapByResId(int resourceId) {

ResourceManager manager = this.getContext().getResourceManager();

if (manager == null) {

return Optional.empty();

}

try (Resource resource = manager.getResource(resourceId)) {

if (resource == null) {

return Optional.empty();

}

ImageSource.SourceOptions srcOpts = new ImageSource.SourceOptions();

srcOpts.formatHint = "image/png";

ImageSource imageSource = ImageSource.create(readResource(resource), srcOpts);

if (imageSource == null) {

return Optional.empty();

}

ImageSource.DecodingOptions decodingOpts = new ImageSource.DecodingOptions();

decodingOpts.desiredSize = new Size(0, 0);

decodingOpts.desiredRegion = new Rect(0, 0, 0, 0);

decodingOpts.desiredPixelFormat = PixelFormat.ARGB_8888;

return Optional.of(imageSource.createPixelmap(decodingOpts));

} catch (NotExistException | IOException e) {

return Optional.empty();

}

}

private  byte[] readResource(Resource resource) {

final int bufferSize = 1024;

final int ioEnd = -1;

byte[] byteArray;

byte[] buffers = new byte[bufferSize];

try (ByteArrayOutputStream output = new ByteArrayOutputStream()) {

while (true) {

int readLen = resource.read(buffers, 0, bufferSize);

if (readLen == ioEnd) {

byteArray = output.toByteArray();

break;

}

output.write(buffers, 0, readLen);

}

} catch (IOException e) {

return new byte[0];

}

return byteArray;

}