创建fragment

布局

布局和fragment的布局是一样的。这里就不解释了

fragment的类

class StudyFragment : Fragment() {
    override fun onCreateView(
        inflater: LayoutInflater,
        container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        return inflater.inflate(R.layout.fragment_study,container,false)
    }
}

这个本质上和java差不多

如何在activity中启动

val fragmentManager = supportFragmentManager
val fragmentTransaction = fragmentManager.beginTransaction()
val study = StudyFragment()
// 判断不同的fragment
fragmentTransaction.add(R.id.appFragment, study)
fragmentTransaction.commit()