RuntimeException when building image viewer

[LouisPennachio]

I would like to instantiate the image viewer before actually showing it but I get this exception when using the "build()" method.

myActivity.runOnUiThread(new Runnable() {
    ImageViewer viewer = new ImageViewer.Builder(getContext(), originalUrls)
        .setStartPosition(0)
        .allowZooming(true)
        .build(); // Crash occurs here

    @Override
    public void run() {
        planImage.setOnClickListener(v -> viewer.show());
    }
});

java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()
at android.os.Handler.(Handler.java:200)
at android.os.Handler.(Handler.java:114)
at android.view.GestureDetector$GestureHandler.(GestureDetector.java:290)
at android.view.GestureDetector.(GestureDetector.java:395)
at android.view.ScaleGestureDetector.setQuickScaleEnabled(ScaleGestureDetector.java:477)
at android.view.ScaleGestureDetector.(ScaleGestureDetector.java:227)
at android.view.ScaleGestureDetector.(ScaleGestureDetector.java:202)
at com.stfalcon.frescoimageviewer.ImageViewerView.init(ImageViewerView.java:143)
at com.stfalcon.frescoimageviewer.ImageViewerView.(ImageViewerView.java:65)
at com.stfalcon.frescoimageviewer.ImageViewer.createDialog(ImageViewer.java:72)
at com.stfalcon.frescoimageviewer.ImageViewer.(ImageViewer.java:53)
at com.stfalcon.frescoimageviewer.ImageViewer$Builder.build(ImageViewer.java:426)

I don't have any issue if I do this instead :

myActivity.runOnUiThread(new Runnable() {
    @Override
    public void run() {
        planImage.setOnClickListener(v -> new ImageViewer.Builder(getContext(), originalUrls)
            .setStartPosition(0)
            .allowZooming(true)
            .show());
    }
});

But I guess it is a waste of resources ?