SimpleCommand框架ImageLoader API详解(三)

ImageLoader API 详细介绍，具体内容如下

在ImageLoader中有以下几个不同的构造器：

 public ImageLoader(Context context, boolean withCache) {
  this(context, null, withCache);
 }

 
 public ImageLoader(Context context, ProgressListener listener, String cachePath) {
  // TODO extend to support multiple libraries as Glide
  // TODO must be initialized and kept as an member instance to avoid losing cache
  Picasso.Builder builder = setupLoaderClientWithCachePath(context, listener, cachePath);
  setupListener(builder);

  picasso = builder.build();
  picasso.setIndicatorsEnabled(BuildConfig.DEBUG);
  picasso.setLoggingEnabled(BuildConfig.DEBUG);
 }

 
 public ImageLoader(Context context, ProgressListener listener, boolean withCache) {
  // TODO extend to support multiple libraries as Glide
  // TODO must be initialized and kept as an member instance to avoid losing cache
  Picasso.Builder builder = setupLoaderClient(context, listener, withCache);
  setupListener(builder);

  picasso = builder.build();
  picasso.setIndicatorsEnabled(BuildConfig.DEBUG);
  picasso.setLoggingEnabled(BuildConfig.DEBUG);
 }

public void shutdown() {
  if (picasso == null) return;

  Logger.d(Logger.TAG, "Image loader has been shutdown");
  picasso.shutdown();
  callback = null;
 }

将ImageLoader停止，一般在Activity停止，或者任务结束时调用此方法将其关闭

public ImageLoader cancelRequest(ImageView imageView) {
  picasso.cancelRequest(imageView);
  return this;
 }

取消之前显示到ImageView上的请求

public ImageLoader load(final int resourceId) {
  cleanResources();
  this.imageResourceId = resourceId;
  return this;
 }

public ImageLoader load(final String imageUri) {
  cleanResources();
  this.imageUri = imageUri;
  return this;
 }

分别加载本地drawable文件夹下的图片，以及网络图片

public ImageLoader withPlaceholder(final int placeholder) {
  this.placeholder = placeholder;
  return this;
 }

设置ImageLoader下载图片时的预览图

public ImageLoader withErrorImage(final int errorImage) {
  this.errorImage = errorImage;
  return this;
 }

下载图片失败时显示的图片

public ImageLoader withTag(final String tag) {
  this.tag = tag;
  return this;
 }

public void pause(final String tag) {
  if (picasso == null) return;

  picasso.pauseTag(tag);
 }

public void resume(final String tag) {
  if (picasso == null) return;

  picasso.resumetag(tag);
 }

以上三个方法依次是

1 下载图片时添加标签tag
2 暂停tag标签的下载任务
3 resume tag标签的下载任务

public ImageLoader withCallback(final Callback callback) {
  this.callback = callback;
  return this;
 }

给ImageLoader设置下载完成的回调，包含onSuccess和onFailed方法

public ImageLoader fit() {
  this.fit = true;
  return this;
 }

 public ImageLoader centerCrop() {
  this.centerCrop = true;
  return this;
 }

 public ImageLoader centerInside() {
  this.centerInside = true;
  return this;
 }

 public ImageLoader resize(final int widthResId, final int heightResId) {
  this.widthResId = widthResId;
  this.heigthResId = heightResId;
  return this;
 }

分别设置Picasso下载图片时的相应属性， 可以参考ImageView的scaleType属性

public void into(final ImageView imageView) {
  run(imageView);
 }

into方法调用内部run方法，并启动下载任务。 此方法需要在以上所有的API之后调用。

框架github地址: SimpleCommand框架

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