java - How can I detect a click in an onTouch listener?

Question

I have a ViewPager inside a ScrollView. I need to be able to scroll horizontally as well as vertically. In order to achieve this had to disable the vertical scrolling whenever my ViewPager is touched (v.getParent().requestDisallowInterceptTouchEvent(true);), so that it can be scrolled horizontally.

But at the same time I need to be able to click the viewPager to open it in full screen mode.

The problem is that onTouch gets called before onClick and my OnClick is never called.

How can I implement both on touch an onClick?

viewPager.setOnTouchListener(new OnTouchListener() {
    @Override
    public boolean onTouch(View v, MotionEvent event) {
        System.out.println("TOUCHED ");
        if(event.getAction() == MotionEvent.???){
            //open fullscreen activity
        }
        v.getParent().requestDisallowInterceptTouchEvent(true); //This cannot be removed
        return false;
    }
});

viewPager.setOnClickListener(new OnClickListener() {
    @Override
    public void onClick(View v) {
        System.out.println("CLICKED ");
        Intent fullPhotoIntent = new Intent(context, FullPhotoActivity.class);
        fullPhotoIntent.putStringArrayListExtra("imageUrls", imageUrls);
        startActivity(fullPhotoIntent);
    }
});

Answer 1

Masoud Dadashi's answer helped me figure it out.

here is how it looks in the end.

viewPager.setOnTouchListener(new OnTouchListener() {
    private int CLICK_ACTION_THRESHOLD = 200;
    private float startX;
    private float startY;

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            startX = event.getX();
            startY = event.getY();
            break;
        case MotionEvent.ACTION_UP: 
            float endX = event.getX();
            float endY = event.getY();
            if (isAClick(startX, endX, startY, endY)) { 
                launchFullPhotoActivity(imageUrls);// WE HAVE A CLICK!!
            }
            break;
        }
        v.getParent().requestDisallowInterceptTouchEvent(true); //specific to my project
        return false; //specific to my project
    }

    private boolean isAClick(float startX, float endX, float startY, float endY) {
        float differenceX = Math.abs(startX - endX);
        float differenceY = Math.abs(startY - endY);
        return !(differenceX > CLICK_ACTION_THRESHOLD/* =5 */ || differenceY > CLICK_ACTION_THRESHOLD);
    } 
}