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ViewPaper2的高度是按照第一个Fragment的高度定死的，所以需要ViewPaper2中每个Fragment都自适应高度

解决方式：

	mBinding.viewPager.registerOnPageChangeCallback(object: OnPageChangeCallback() {
            override fun onPageSelected(position: Int) {
                super.onPageSelected(position)
                updateHeight(position)
            }
        })
        
	new TabLayoutMediator(TabLayout, ViewPager2, new TabLayoutMediator.TabConfigurationStrategy() {
            @Override
            public void onConfigureTab(@NonNull @NotNull TabLayout.Tab tab, int position) {
                updateHeight(position);
            }
        }).attach();

	fun updateHeight(position: Int) {
        if (mFragments.size > position) {
            val fragment: Fragment = mFragments.get(position)
            if (fragment.view != null) {
                val viewWidth = View.MeasureSpec.makeMeasureSpec(
                    fragment.view!!.width, View.MeasureSpec.EXACTLY
                )
                val viewHeight = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED)
                fragment.view!!.measure(viewWidth, viewHeight)
                if (mBinding.viewPager.getLayoutParams().height != fragment.view!!.measuredHeight) {
                    //必须要用对象去接收，然后修改该对象再采用该对象，否则无法生效...
                    val layoutParams: ViewGroup.LayoutParams = mBinding.viewPager.getLayoutParams()
                    layoutParams.height = fragment.view!!.measuredHeight                 
                    mBinding.viewPager.setLayoutParams(layoutParams)
                }
            }
        }
    }

解决过程中出现的问题

问题1：RecyclerView列表顶部出现莫名空白部分



原因：ViewPager2里加载的Fragment xml布局里有android:fitsSystemWindows=”true”导致



解决：去掉android:fitsSystemWindows=“true”

问题2：首次进入页面出现第一个Fragment被裁切布局，显示不全

原因：接口数据返回较慢，已经进入该页面时首个Fragment已初始化完毕造成裁切问题



解决：接口请求完成数据适配完成后再调用updateHeight()

参考链接