Android使用Kotlin实现多节点进度条

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

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

来源：https://blog.csdn.net/c1312052256/article/details/78115848