public GenericRequestBuilder<ModelType, DataType, ResourceType, TranscodeType> error(
            Drawable drawable) {
        this.errorPlaceholder = drawable;

        return this;
    }
Sets a {@link Drawable} to display if a load fails.

@param drawable The drawable to display.
@return This request builder.
core/src/main/java/com/bumptech/glide/GenericRequestBuilder.java