【Android,kotlin】不再生硬!多Fragment切换的解决方案

Fragment切换的解决方案

效果

点击左右划皆可,非常的丝滑…

底层

​​adapter​​

open class TabAdapterMK(private val tabList: List<Fragment>, fragmentManager: FragmentManager) :
    FragmentPagerAdapter(fragmentManager) {
    override fun getCount() = tabList.size

    override fun getItem(position: Int): Fragment = tabList[position]
}

Kotlin代码 (activity,fragment)

​​initView <- onCreate()​​

//点击事件注册
vb.mainTab1.setOnClickListener(this)
vb.mainTab2.setOnClickListener(this)
initFragmentPager()

​​Viewpaper初始化​​

private fun initFragmentPager() {
    val tabList = arrayListOf<Fragment>(FragmentOne(), FragmentTwo())
    val adapterMK = TabAdapterMK(tabList, supportFragmentManager)
    vb.mainViewpager.adapter = adapterMK
    vb.mainViewpager.setOnPageChangeListener(object : ViewPager.OnPageChangeListener {
        override fun onPageScrolled(position: Int,positionOffset: Float,positionOffsetPixels: Int) {}
        override fun onPageSelected(position: Int) {
            when (position) {
                1 -> {vm.uiSelectedTab.setValue(1)}
                else -> {vm.uiSelectedTab.setValue(0)}
            }
        }
        override fun onPageScrollStateChanged(state: Int) {}
    })
}

​​onClick:​​

override fun onClick(v: View?) {
  when (v?.id) {
      R.id.main_tab_1 -> {
          vb.mainViewpager.setCurrentItem(0, false)}
    R.id.main_tab_2 -> {
          vb.mainViewpager.setCurrentItem(1, false)
    }
  }
}

布局

​​activity_main​​

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:toolbar="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools">

    <data>

        <variable
            name="vm"
            type="com.mozhimen.app.MainViewModel" />
    </data>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:gravity="center"
        android:orientation="vertical">

        <androidx.viewpager.widget.ViewPager
            android:id="@+id/main_viewpager"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="13"
            app:layout_behavior="@string/appbar_scrolling_view_behavior" />

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1"
            android:orientation="horizontal">

            <TextView
                android:id="@+id/main_tab_1"
                android:layout_width="0dp"
                android:layout_height="match_parent"
                android:layout_weight="1"
                android:background="@{vm.uiSelectedTab==0?@color/lightBlue:@color/white}"
                android:gravity="center"
                android:text="one"
                tools:ignore="HardcodedText" />

            <TextView
                android:id="@+id/main_tab_2"
                android:layout_width="0dp"
                android:layout_height="match_parent"
                android:layout_weight="1"
                android:background="@{vm.uiSelectedTab==1?@color/lightBlue:@color/white}"
                android:gravity="center"
                android:text="two"
                tools:ignore="HardcodedText" />

        </LinearLayout>
    </LinearLayout>
</layout>