Question

我想在Async任务中加载所有资源。我对此并不清楚，也无法从网上找到任何相关的例子。

看起来使用AssetManager是一次加载资产的最佳方式。但是我有一些资产，比如龙骨动画，这是AssetManager无法加载的。

我创建了一个这样的界面：

public interface IAsyncCallBack {

  public abstract void WorkToDo();     
  public abstract void onFinish();

 }

在MyGdxClass的create方法中，我定义了方法体：

   final AsyncCallBack callback = new AsyncCallBack() {

        @Override
        public void WorkToDo() {
            // TODO Auto-generated method stub
            loadAssets();
        }

        @Override
        public void onFinish() {
         isLoaded = true;
            // TODO Auto-generated method stub

        }

     };

但我不知道用LibGdx创建AsyncTask并用它加载资产。任何帮助将不胜感激。

提前致谢。

Answer 1

您可以使用libgdx AsynchronousAssetLoader接口来定义自己的加载器。此代码取自BitmapFont Loader，它加载字体并具有需要加载的额外文件。

package com.badlogic.gdx.assets.loaders;

import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.assets.AssetDescriptor;
import com.badlogic.gdx.assets.AssetLoaderParameters;
import com.badlogic.gdx.assets.AssetManager;
import com.badlogic.gdx.files.FileHandle;
import com.badlogic.gdx.graphics.Texture;
import com.badlogic.gdx.graphics.Texture.TextureFilter;
import com.badlogic.gdx.graphics.g2d.BitmapFont;
import com.badlogic.gdx.graphics.g2d.BitmapFont.BitmapFontData;
import com.badlogic.gdx.graphics.g2d.TextureAtlas;
import com.badlogic.gdx.graphics.g2d.TextureAtlas.AtlasRegion;
import com.badlogic.gdx.graphics.g2d.TextureRegion;
import com.badlogic.gdx.scenes.scene2d.ui.Skin;
import com.badlogic.gdx.utils.Array;
import com.badlogic.gdx.utils.GdxRuntimeException;

/** {@link AssetLoader} for {@link BitmapFont} instances. Loads the font description file (.fnt) asynchronously, loads the
 * {@link Texture} containing the glyphs as a dependency. The {@link BitmapFontParameter} allows you to set things like texture
 * filters or whether to flip the glyphs vertically.
 * @author mzechner */
public class BitmapFontLoader extends AsynchronousAssetLoader<BitmapFont, BitmapFontLoader.BitmapFontParameter> {
    public BitmapFontLoader (FileHandleResolver resolver) {
        super(resolver);
    }

    BitmapFontData data;

    @Override
    public Array<AssetDescriptor> getDependencies (String fileName, FileHandle file, BitmapFontParameter parameter) {
        Array<AssetDescriptor> deps = new Array();
        if (parameter != null && parameter.bitmapFontData != null) {
            data = parameter.bitmapFontData;
            return deps;
        }

        data = new BitmapFontData(file, parameter != null ? parameter.flip : false);
        if (parameter != null && parameter.atlasName != null) {
            deps.add(new AssetDescriptor(parameter.atlasName, TextureAtlas.class));
        } else {
            for (int i = 0; i < data.getImagePaths().length; i++) {
                String path = data.getImagePath(i);
                FileHandle resolved = resolve(path);

                TextureLoader.TextureParameter textureParams = new TextureLoader.TextureParameter();

                if (parameter != null) {
                    textureParams.genMipMaps = parameter.genMipMaps;
                    textureParams.minFilter = parameter.minFilter;
                    textureParams.magFilter = parameter.magFilter;
                }

                AssetDescriptor descriptor = new AssetDescriptor(resolved, Texture.class, textureParams);
                deps.add(descriptor);
            }
        }

        return deps;
    }

    @Override
    public void loadAsync (AssetManager manager, String fileName, FileHandle file, BitmapFontParameter parameter) {
    }

    @Override
    public BitmapFont loadSync (AssetManager manager, String fileName, FileHandle file, BitmapFontParameter parameter) {
        if (parameter != null && parameter.atlasName != null) {
            TextureAtlas atlas = manager.get(parameter.atlasName, TextureAtlas.class);
            String name = file.sibling(data.imagePaths[0]).nameWithoutExtension().toString();
            AtlasRegion region = atlas.findRegion(name);

            if (region == null)
                throw new GdxRuntimeException("Could not find font region " + name + " in atlas " + parameter.atlasName);
            return new BitmapFont(file, region);
        } else {
            int n = data.getImagePaths().length;
            Array<TextureRegion> regs = new Array(n);
            for (int i = 0; i < n; i++) {
                regs.add(new TextureRegion(manager.get(data.getImagePath(i), Texture.class)));
            }
            return new BitmapFont(data, regs, true);
        }
    }

    /** Parameter to be passed to {@link AssetManager#load(String, Class, AssetLoaderParameters)} if additional configuration is
     * necessary for the {@link BitmapFont}.
     * @author mzechner */
    static public class BitmapFontParameter extends AssetLoaderParameters<BitmapFont> {
        /** Flips the font vertically if {@code true}. Defaults to {@code false}. **/
        public boolean flip = false;

        /** Generates mipmaps for the font if {@code true}. Defaults to {@code false}. **/
        public boolean genMipMaps = false;

        /** The {@link TextureFilter} to use when scaling down the {@link BitmapFont}. Defaults to {@link TextureFilter#Nearest}. */
        public TextureFilter minFilter = TextureFilter.Nearest;

        /** The {@link TextureFilter} to use when scaling up the {@link BitmapFont}. Defaults to {@link TextureFilter#Nearest}. */
        public TextureFilter magFilter = TextureFilter.Nearest;

        /** optional {@link BitmapFontData} to be used instead of loading the {@link Texture} directly. Use this if your font is
         * embedded in a {@link Skin}. **/
        public BitmapFontData bitmapFontData = null;

        /** The name of the {@link TextureAtlas} to load the {@link BitmapFont} itself from. Optional; if {@code null}, will look for
         * a separate image */
        public String atlasName = null;
    }
}

主要思想是有一个参数类，它定义加载资产所需的所有额外部分，然后在你创建的加载方法中，并返回资产对象。

使用Async task-Libgdx加载所有资产

1 个答案: