Android使用Kotlin实现多节点进度条（时间轴）

时间轴主要使用Recyclerview来实现。开发语言使用Kotlin，代码相对java少了许多也简洁许多

源代码下载地址：http://download.youkuaiyun.com/download/c1312052256/9998399

效果图：

MainActivity.kt

package com.example.lee.linenode

import android.annotation.SuppressLint
import android.os.Build
import android.support.v7.app.AppCompatActivity
import android.os.Bundle
import android.support.v7.widget.LinearLayoutManager
import kotlinx.android.synthetic.main.activity_main.*
import kotlinx.android.synthetic.main.item_line_node.view.*

class MainActivity : AppCompatActivity() {
    private var list = arrayListOf<StepBean>()
    private var lineNodeAdapter: LineNodeAdapter<StepBean>? = null
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        initRecyclerView()
    }

    private fun initRecyclerView() {
        getData()
        //创建一个继承于抽象类(LineNodeAdapter)的实例
        lineNodeAdapter = object : LineNodeAdapter<StepBean>(this, list) {
            override fun convert(viewHolder: LineNodeViewHolder, t: StepBean) {
                viewHolder.itemView.title_txt.text = t.title
                viewHolder.itemView.time_txt.text = t.time
                viewHolder.itemView.num_txt.text = t.num.toString()
                if (t.num == 1) {
                    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
                        viewHolder.itemView.left_view.background = null
                    }
                }
                if (t.num == 4) {
                    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
                        viewHolder.itemView.right_view.background = null
                    }
                }
                if (t.num < 3) viewHolder.itemView.num_txt.setBackgroundResource(R.drawable.shap_line_number_circle_red)
            }

        }
        val linearLayoutManager = LinearLayoutManager(this)
        linearLayoutManager.orientation = LinearLayoutManager.HORIZONTAL
        //使用来自主代码集的 R.layout.activity_main,而不是 findViewById(R.id.ln_recycler_view) as Recyclerview
        ln_recycler_view.layoutManager = linearLayoutManager
        ln_recycler_view.adapter = lineNodeAdapter
    }

    private fun getData() {
        for (i in 1..4) {
            list.add(StepBean(i, "2017-9-27\n17:1$i", "步骤$i"))
        }


    }
}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/ln_recycler_view"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true" />

</RelativeLayout>

LineNodeAdapter.kt //RecyclerView的适配器

package com.example.lee.linenode

import android.content.Context
import android.support.v7.widget.RecyclerView
import android.support.v7.widget.RecyclerView.Adapter
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import kotlinx.android.synthetic.main.item_line_node.view.*

/**
 * Created by lee on 17-9-27.
 */
abstract class LineNodeAdapter<T>(val context: Context, val list: List<T>) : Adapter<LineNodeAdapter.LineNodeViewHolder>() {
    override fun onCreateViewHolder(parent: ViewGroup?, viewType: Int): LineNodeViewHolder {
        return LineNodeViewHolder(LayoutInflater.from(context).inflate(R.layout.item_line_node, parent, false))
    }

    override fun onBindViewHolder(viewHolder: LineNodeViewHolder, position: Int) {
        convert(viewHolder, list.get(position))
    }


    abstract fun convert(viewHolder: LineNodeViewHolder, t: T)

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

    class LineNodeViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
    }
}

item_line_node.xml //这个文件是时间轴item的布局文件

<?xml version="1.0" encoding="utf-8"?>

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

    <TextView
        android:id="@+id/title_txt"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:text="步骤" />

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:gravity="center_vertical"
        android:orientation="horizontal">

        <View
            android:id="@+id/left_view"
            android:layout_width="30dp"
            android:layout_height="1dp"
            android:layout_centerVertical="true"
            android:background="#A6A6A6" />

        <TextView
            android:id="@+id/num_txt"
            android:layout_width="20dp"
            android:layout_height="20dp"
            android:background="@drawable/shap_line_number_circle_grey"
            android:gravity="center"
            android:text="1"
            android:textColor="@color/colorWhite" />

        <View
            android:id="@+id/right_view"
            android:layout_width="30dp"
            android:layout_height="1dp"
            android:layout_centerVertical="true"
            android:background="#A6A6A6" />
    </LinearLayout>


    <TextView
        android:id="@+id/time_txt"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:gravity="center_horizontal"
        android:text="2017-09-27\n15:56" />
</LinearLayout>

StepBean.kt //时间节点实体类

package com.example.lee.linenode

/**
 * Created by lee on 17-9-27.
 */
class StepBean(var num: Int, var time: String, var title: String)//直接在主构造函数里声明属性