setMaxLifecycle 的使用方法

demo地址：
https://github.com/newPersonKing/SetMaxLifecycle_TestFragmentState.git

声明周期执行的几种流程
1 设置为STARTED

    val beginTransaction = supportFragmentManager.beginTransaction()
        beginTransaction.add(R.id.fl_main, fragment)
        beginTransaction.setMaxLifecycle(fragment,Lifecycle.State.STARTED)
        beginTransaction.commit()

1.1 fragment 的声明周期只能执行到 OnStart
1.2 切换到后台 直接执行 onStop
1.3 再切换到前台, 直接执行onStart

2 设置为CREATED

    val beginTransaction = supportFragmentManager.beginTransaction()
        beginTransaction.add(R.id.fl_main, fragment)
        beginTransaction.setMaxLifecycle(fragment,Lifecycle.State.CREATED)
        beginTransaction.commit()

2.1 声明周期只走到onCreate
2.2 切换到后台 不执行方法
2.3 切换到 前台 不执行方法
3 设置为 RESUMED

  val beginTransaction = supportFragmentManager.beginTransaction()
      beginTransaction.add(R.id.fl_main, fragment)
      beginTransaction.setMaxLifecycle(fragment,Lifecycle.State.RESUMED)
      beginTransaction.commit()

3.1 声明周期流程跟正常的流程一致

4 STARTED -> CREATED

    val beginTransaction = supportFragmentManager.beginTransaction()
        beginTransaction.add(R.id.fl_main, fragment)
        beginTransaction.setMaxLifecycle(fragment,Lifecycle.State.STARTED)
        beginTransaction.commit()

    btn_main_frg_1.setOnClickListener {
            val beginTransaction = supportFragmentManager.beginTransaction()
            beginTransaction.setMaxLifecycle(fragment, androidx.lifecycle.Lifecycle.State.CREATED)
            beginTransaction.commitNow()
        }

4.1 立即执行 onStop -> onDestroyView
4.2 之后行为跟直接设置CREATED一致

5 RESUMED -> CREATED

    val beginTransaction = supportFragmentManager.beginTransaction()
        beginTransaction.add(R.id.fl_main, fragment)
        beginTransaction.setMaxLifecycle(fragment,Lifecycle.State.RESUMED)
        beginTransaction.commit()

    btn_main_frg_1.setOnClickListener {
            val beginTransaction = supportFragmentManager.beginTransaction()
            beginTransaction.setMaxLifecycle(fragment, androidx.lifecycle.Lifecycle.State.CREATED)
            beginTransaction.commitNow()
        }

5.1 立即执行 onPause->onStop -> onDestroyView
5.2 之后行为跟直接设置CREATED一致

6 CREATED -> STARTED

    val beginTransaction = supportFragmentManager.beginTransaction()
        beginTransaction.add(R.id.fl_main, fragment)
        beginTransaction.setMaxLifecycle(fragment,Lifecycle.State.CREATED)
        beginTransaction.commit()

    btn_main_frg_1.setOnClickListener {
            val beginTransaction = supportFragmentManager.beginTransaction()
            beginTransaction.setMaxLifecycle(fragment, androidx.lifecycle.Lifecycle.State.STARTED)
            beginTransaction.commitNow()
        }

6.1 立即执行 onCreateView->onActivityCreated -> onStart
6.2 之后行为跟直接设置STARTED一致

 7 CREATED -> RESUMED

    val beginTransaction = supportFragmentManager.beginTransaction()
        beginTransaction.add(R.id.fl_main, fragment)
        beginTransaction.setMaxLifecycle(fragment,Lifecycle.State.CREATED)
        beginTransaction.commit()

    btn_main_frg_1.setOnClickListener {
            val beginTransaction = supportFragmentManager.beginTransaction()
            beginTransaction.setMaxLifecycle(fragment, androidx.lifecycle.Lifecycle.State.RESUMED)
            beginTransaction.commitNow()
        }

7.1 立即执行 onCreateView->onActivityCreated -> onStart -> onResume
7.2 之后行为跟直接设置RESUMED一致

 8 STARTED -> RESUMED

    val beginTransaction = supportFragmentManager.beginTransaction()
        beginTransaction.add(R.id.fl_main, fragment)
        beginTransaction.setMaxLifecycle(fragment,Lifecycle.State.STARTED)
        beginTransaction.commit()

    btn_main_frg_1.setOnClickListener {
            val beginTransaction = supportFragmentManager.beginTransaction()
            beginTransaction.setMaxLifecycle(fragment, androidx.lifecycle.Lifecycle.State.RESUMED)
            beginTransaction.commitNow()
        }

8.1 立即执行 onResume
8.2 之后行为跟直接设置RESUMED一致