Android 弹性布局 FlexboxLayout （四）：recyclerview流式布局

测试

activity_main.xml :

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <Button
        android:id="@+id/btn"
        android:layout_width="match_parent"
        android:layout_height="60dp"
        android:layout_marginStart="20dp"
        android:layout_marginTop="20dp"
        android:layout_marginEnd="20dp"
        android:layout_marginBottom="20dp"
        android:text="随机" />

    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/rv"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        tools:itemCount="10"
        tools:listitem="@layout/layout_item" />
LinearLayout>

item.xml：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:gravity="center">


    <TextView
        android:id="@+id/tvTitle"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:gravity="center"
        android:padding="5dp"
        android:text="xq"
        android:textColor="#000"
        android:textSize="20sp"
        android:textStyle="bold" />

LinearLayout>

class TestActivity  :AppCompatActivity(){

    private val dataList = ArrayList<String>()
    private val colorList = ArrayList<Int>()

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        initDataArray()
        initColorArray()

		//将正常的manager替换为FlexboxLayoutManager
        val layoutManager = FlexboxLayoutManager(this)
        layoutManager.flexDirection = FlexDirection.ROW
        layoutManager.justifyContent = JustifyContent.FLEX_START
        layoutManager.alignItems = AlignItems.CENTER
        rv.layoutManager = layoutManager

        val adapter = FlexboxAdapter(this, dataList, colorList)
        rv.adapter = adapter

        btn.setOnClickListener {
            adapter.notifyDataSetChanged()
        }
    }
    private fun initColorArray() {
        colorList.add(Color.RED)
        colorList.add(Color.GREEN)
        colorList.add(Color.BLUE)
        colorList.add(Color.GRAY)
        colorList.add(Color.DKGRAY)
        colorList.add(Color.LTGRAY)
        colorList.add(Color.CYAN)
        colorList.add(Color.YELLOW)
        colorList.add(Color.MAGENTA)
    }

    private fun initDataArray() {
        dataList.add("1234567890abcd")
        dataList.add("1234567890abcdefg")
        dataList.add("1")
        dataList.add("1234567890abcdefgh")
        dataList.add("1234567890abcdefghij")
        dataList.add("12345")
        dataList.add("1234567890abcdefghijklmnop")
        dataList.add("123456789")
        dataList.add("1234567890abcdefghijklmn")
        dataList.add("1234")
        dataList.add("1234567890ab")
        dataList.add("1234567890abcdefghi")
        dataList.add("1234567890abc")
        dataList.add("1234567890abcdefghijklmnopqrs")
        dataList.add("1234567890abcdefghijk")
        dataList.add("1234567890")
        dataList.add("1234567890a")
        dataList.add("12")
        dataList.add("1234567890abcdefghijklm")
        dataList.add("12345678")
        dataList.add("123")
        dataList.add("1234567890abcde")
        dataList.add("123456")
        dataList.add("1234567")
        dataList.add("1234567890abcdefghijklmno")
        dataList.add("1234567890abcdef")
        dataList.add("1234567890abcdefghijkl")
    }
}

private class FlexboxAdapter(
    private val context: Context,
    private val dataList: ArrayList<String>,
    private val colorList: ArrayList<Int>
) : RecyclerView.Adapter<FlexboxAdapter.ViewHolder>() {
    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
        val view: View = LayoutInflater.from(context).inflate(R.layout.item, parent, false)
        return ViewHolder(view)
    }

    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
        holder.title.text = dataList[Random().nextInt(dataList.size)]
        holder.title.setBackgroundColor(colorList[Random().nextInt(colorList.size)])
    }

    override fun getItemCount(): Int {
        return dataList.size
    }

    internal inner class ViewHolder(itemView: View) :
        RecyclerView.ViewHolder(itemView) {
        var title: TextView = itemView.findViewById(R.id.tvTitle)
    }

}

效果图：