如何使用 Kotlin 在 Android 上的 ListView 中创建可聚焦的 EditText?
kotlin androidapps/applicationsmobile development更新于 2026/2/15 8:52:17
本示例演示了如何使用 Kotlin 在 Android 上的 ListView 中创建可聚焦的 EditText。
步骤 1 − 在 Android Studio 中创建一个新项目，前往"文件">"新建项目"，并填写所有必填信息以创建新项目。
步骤 2 − 将以下代码添加到 res/layout/activity_main.xml。
示例
<?xml version="1.0" encoding="utf-8"?> <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" android:padding="4dp" tools:context=".MainActivity"> <ListView android:id="@+id/listView" android:layout_width="fill_parent" android:layout_height="fill_parent" android:descendantFocusability="beforeDescendants" /> </LinearLayout>
步骤 3 − 将以下代码添加到 src/MainActivity.kt
import androidx.appcompat.app.AppCompatActivity
import android.annotation.SuppressLint
import android.app.LauncherActivity
import android.content.Context
import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.BaseAdapter
import android.widget.EditText
import android.widget.ListView
import java.util.ArrayList
class MainActivity : AppCompatActivity() {
private lateinit var listView: ListView
private lateinit var myAdapter: MyAdapter
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
title = "KotlinApp"
listView = findViewById(R.id.listView)
listView.itemsCanFocus = true
myAdapter = MyAdapter()
listView.adapter = myAdapter
}
private inner class MyAdapter internal constructor() : BaseAdapter() {
private var layoutInflater: LayoutInflater = getSystemService(Context.LAYOUT_INFLATER_SERVICE) as
LayoutInflater
internal var myItems = ArrayList<LauncherActivity.ListItem>()
lateinit var context: Context
init {
for (i in 0..6) {
val listItem = LauncherActivity.ListItem()
listItem.className = "Caption$i"
myItems.add(listItem)
}
notifyDataSetChanged()
}
override fun getItem(position: Int): Any {
return position
}
override fun getItemId(position: Int): Long {
return position.toLong()
}
override fun getCount(): Int {
return myItems.size
}
@SuppressLint("InflateParams")
override fun getView(position: Int, convertView: View?, parent: ViewGroup): View? {
var convertView: View? = convertView
val holder: ViewHolder
if (convertView == null) {
holder = ViewHolder()
convertView = layoutInflater.inflate(R.layout.list, null)
holder.caption = convertView.findViewById(R.id.ItemCaption)
convertView.setTag(holder)
} else {
holder = convertView.tag as ViewHolder
}
holder.caption.setText(myItems.get(position).className)
holder.caption.id = position
holder.caption.onFocusChangeListener = View.OnFocusChangeListener { v, hasFocus ->
if (!hasFocus) {
val position = v.id
val caption = v as EditText
myItems[position].className = caption.text.toString()
}
}
return convertView
}
}
internal inner class ViewHolder {
lateinit var caption: EditText
}
}
步骤 4 − 创建布局资源文件(list.xml)并添加以下代码
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" android:paddingStart="4dp"> <EditText android:id="@+id/ItemCaption" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_marginStart="2dip" android:singleLine="true" /> </LinearLayout>
步骤 5 − 将以下代码添加到 AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.example.q11"> <application android:allowBackup="true" android:icon="@mipmap/ic_launcher" android:label="@string/app_name" android:roundIcon="@mipmap/ic_launcher_round" android:supportsRtl="true" android:theme="@style/AppTheme"> <activity android:name=".MainActivity"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest>
让我们尝试运行您的应用程序。假设您已将实际的 Android 移动设备连接到电脑。要从 Android Studio 运行该应用程序，请打开项目的某个活动文件，然后点击工具栏上的"运行"图标
。选择您的移动设备作为选项，然后勾选将显示默认屏幕的移动设备
点击此处下载项目代码。
