GlideRequest.java 文件源码

/**
 * @see GlideOptions#fallback(int)
 */
@CheckResult
public GlideRequest<TranscodeType> fallback(@DrawableRes int arg0) {
  if (getMutableOptions() instanceof GlideOptions) {
    this.requestOptions = ((GlideOptions) getMutableOptions()).fallback(arg0);
  } else {
    this.requestOptions = new GlideOptions().apply(this.requestOptions).fallback(arg0);
  }
  return this;
}