Question

我有一个应用程序，它是由Kotlin开发的。我的活动之一是使用带有viewpager的选项卡布局（例如发送广告接收）。在``发送''选项卡中包含A，B，C之类的数据。在接收标签1,2,3中。来自数据库的所有数据。我想用新数据（如D，E，F .. 4,5,6 .....）更新viewpaer / tabview。我尝试了几种方法，但没有用。

注意：我不想用旧数据刷新TabLayout，因为它可以工作。我只需要如何绑定新数据。当我关闭应用程序并再次打开时，它将更新为新数据，但是如果没有关闭应用程序，它将无法正常工作。

private fun setupViewPager(viewPager: ViewPager, it: List<TransactionEntity>?, incoming: TransactionAdapterDirection) {

            if (incoming.equals(OUTGOING)) {
                adapter.addFragment(SendingFragment(it!!, appDatabase, OUTGOING, networkDefinitionProvider), "SEND")
                adapter.notifyDataSetChanged() //KK
            } else if (incoming.equals(INCOMING)) {
                adapter.addFragment(ReceiveFragment(it!!, appDatabase, INCOMING, networkDefinitionProvider), "RECEIVE")
                adapter.notifyDataSetChanged() //KK
            }

            viewPager.addOnPageChangeListener(object : ViewPager.OnPageChangeListener {

                override fun onPageScrollStateChanged(state: Int) {
                }

                override fun onPageScrolled(position: Int, positionOffset: Float, positionOffsetPixels: Int) {

                }
                override fun onPageSelected(position: Int) {


                }

            })

            viewPager.adapter = adapter
    }


    inner class ViewPagerAdapter(manager: FragmentManager) : FragmentStatePagerAdapter(manager) {
        private val mFragmentList = ArrayList<Fragment>()
        private val mFragmentTitleList = ArrayList<String>()

        override fun getItem(position: Int): Fragment {
            return mFragmentList[position]
        }

        override fun getCount(): Int {
            return mFragmentList.size
        }

        fun addFragment(fragment: Fragment, title: String) {
            mFragmentList.add(fragment)
            mFragmentTitleList.add(title)
        }

        override fun getPageTitle(position: Int): CharSequence {
            return mFragmentTitleList[position]
        }

        override fun getItemPosition(`object`: Any): Int {
            return PagerAdapter.POSITION_NONE
        }
    }

更新：

override fun getItem(position: Int): Fragment {

            if(this.count < 3) {
                mFragmentList.add(ReceiveFragment(mfragmentIT, mfragmentAB, mfragmentINC, mfragmentnetwork))
                mFragmentList.add(SendingFragment(mfragmentIT, mfragmentAB, mfragmentINC, mfragmentnetwork))
                for (i in 1..3) {
                    println(i)
                }
            }
            return mFragmentList.get(i)
        }

更新2：

override fun getItem(position: Int): Fragment {
            if (position == 0) {
                val tab1 = this.addFragment(com.crypto.wallet.activities.ReceiveFragment(mfragmentIT,mfragmentAB,mfragmentINC,mfragmentnetwork), "RECEIVE")
                return tab1 as Fragment
            } else {
                val tab2 = this.addFragment(com.crypto.wallet.activities.SendingFragment(mfragmentIT,mfragmentAB,mfragmentINC,mfragmentnetwork), "SEND")
                return tab2 as Fragment
            }
        }

如何使用Kotlin用新内容更新viewpager？

0 个答案: