将 java 类转换为从 FragmentStatePageAdapter 继承的 kotlin

Question

I am doing a project and the only help I have are in java, and it is making it very difficult for me to have to convert it or pass it to kotlin this is the code I have to pass to kotlin:

private class ScreenSliderPagerAdapter extends FragmentStatePagerAdapter
    {
        public ScreenSliderPagerAdapter(@NonNull FragmentManager fm)
        {
            super(fm);
        }
        @NonNull
        @Override
        public Fragment getItem(int position)
        {
            switch(position)
            {
                case 0:
                    SwipeFragement1 tab1 = new SwipeFragement1();
                    return tab1;
                case 1:
                    SwipeFragement2 tab2 = new SwipeFragement2();
                    return tab2;
                case 2:
                    SwipeFragemen3 tab3 = new SwipeFragement3();
                    return tab3;
            }
            return null;
        }
        @Override
        public int getCount()
        {
            return 0:
        }
    }

and when trying to convert it, it was more or less like this:

private class ScreenSliderPagerAdapter (fm : FragmentManager @NonNull) : FragmentStatePagerAdapter
    {
        var fm : FragmentManager = fm
        
        constructor():this()
        {
            super(fm)
        }
        @NonNull
        @Override
        public fun getItem(position: Int): SwipeFragement1?
        {
            var tab : SwipeFragement1? = null
            when(position)
            {
                0 -> tab = SwipeFragement1()
                1 -> tab = SwipeFragement2()
                2 -> tab = SwipeFragement3()
            }
            return tab
        }
        @Override
        public fun getCount(): Int
        {
            return 0
        }
    }

According to how little I know, Kotlin is looking very bad as seen in the following screenshot:

In case you're wondering I'm trying to fragment an actity

Answer 1

You got that error because the Kotlin code has some syntax errors. Here is the right one.

private class ScreenSliderPagerAdapter(fm: FragmentManager) :
    FragmentStatePagerAdapter(fm) {

    val NUM_TABS = 3
    
    override fun getItem(position: Int): Fragment {
        return when (position) {
            0 -> SwipeFragement1()
            1 -> SwipeFragement2()
            else -> SwipeFragement3()
        }
    }

    override fun getCount(): Int {
        return NUM_TABS
    }
}