CoolNavigationBar

Cool Menu

In this project i have implement a menu using view pager. I first tried it will Navigation bar , so the name of the project.
To implement this menu , i have used view pager. First and third page are the menu page , and second page is our content
frame.

When we slide our page , say left to right. when first menu appear. What i have done is.

Set the page translation of first page (one with negative position offset) to 0

Resize The content page

Shift the content page to align to parent right

Implementing Page Transformation

PageTransformer is the interface which will control all our transformation.

@Override public void transformPage(@NonNull View page, float position) {

    if(position<-1)
        page.setAlpha(0);
    else if(position>1)
        page.setAlpha(0);

    else page.setAlpha(1);


    if(page.getId() == R.id.menu){
        page.setTranslationX(-position*page.getWidth());
    }

    else if(page.getId() == R.id.content){

        if(position>0) {

            float pos = Math.abs(position);
            float scale = Math.max(.5f, 1 - pos);
            page.setScaleY(scale);
            page.setScaleX(scale);

            float pageWidth = page.getWidth();
            float pageScaleWidth = scale * pageWidth;
            float deltaWidth = pageWidth - pageScaleWidth;

            page.setTranslationX((1 - position) * page.getWidth() - pageScaleWidth - deltaWidth / 2);


            Log.e(TAG, "transformpage : content" + page.getWidth() + " " + deltaWidth
                    + "  " + pageScaleWidth);

        }

        else if(position<0){
            float pos = Math.abs(position);
            float scale = Math.max(.5f, 1 - pos);
            page.setScaleY(scale);
            page.setScaleX(scale);

            float pageWidth = page.getWidth();
            float pageScaleWidth = scale * pageWidth;
            float deltaWidth = pageWidth - pageScaleWidth;

            page.setTranslationX(-position* page.getWidth()-deltaWidth/2);


            Log.e(TAG, "transformpage : content" + page.getWidth() + " " + deltaWidth
                    + "  " + pageScaleWidth);

        }
    }

    else if(page.getId() == R.id.menu2){
        page.setTranslationX(-position*page.getWidth());
        Log.e(TAG, "transformPage: menu 2" );
    }
    else
    Log.e(TAG,"something wrong");
}