Kotlin 引言
Google IO 2017 宣布了 Kotlin 会成为 Android 官方开发语言。
Kotlin 是一个基于 JVM 的新的编程语言，由 JetBrains 开发。
Kotlin可以编译成Java字节码，也可以编译成JavaScript，方便在没有JVM的设备上运行。
JetBrains，作为目前广受欢迎的Java IDE IntelliJ 的提供商，在 Apache 许可下已经开源其Kotlin 编程语言。
Kotlin已正式成为Android官方开发语言。
正文
今天我主要介绍的是使用Kotlin去写一个简单的自定义View，从而学习Kotlin语言的各种魅力。
Gradle引入
model中
apply plugin: 'kotlin-android'
android {
sourceSets {
main.java.srcDirs += 'src/main/kotlin'
}
}
compile 'org.jetbrains.kotlin:kotlin-stdlib:1.1.2-4'
工程中引入
buildscript {
ext.kotlin_version = '1.1.2-4'
repositories {
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:2.3.2'
classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}
}
Kotlin代码
常量：ActionSheetConstants.kt
/**
* Created by zyao89 on 2017/5/24.
* Contact me at 305161066@qq.com or zyao89@gmail.com
* For more projects: https://github.com/zyao89
* My Blog: http://zyao89.me
*/
const val DEFAULT_COLOR: Int = 0xFF_02_7B_FF.toInt()
const val DEFAULT_SHADE_COLOR: Int = 0x88_00_00_00.toInt()
const val DEFAULT_BTN_CANCEL_COLOR: Int = 0xFF_87_87_87.toInt()
const val DEFAULT_BTN_SELECT_COLOR: Int = 0xFF_3D_DD_B0.toInt()
代码块一： BaseActionSheetView.kt
/**
* Created by zyao89 on 2017/5/24.
* Contact me at 305161066@qq.com or zyao89@gmail.com
* For more projects: https://github.com/zyao89
* My Blog: http://zyao89.me
*/
abstract class BaseActionSheetView(val context: Context, val list: List<ActionSheetBtnInfo>, val rootView: ViewGroup = ((context as Activity).window.decorView as ViewGroup)) : View.OnClickListener, View.OnTouchListener {
protected val mBtnViewList: LinkedList<TextView> = LinkedList()
protected var mCustomContent: LinearLayout? = null
protected var mBtnCancel: TextView? = null
//POP总容器
private var mFrameLayout: FrameLayout = FrameLayout(context)
.apply {
setBackgroundColor(DEFAULT_SHADE_COLOR)
}
private var mPopupWindow: PopupWindow = PopupWindow(this.initView()
.apply {
mCustomContent = findViewById(R.id.pop_layout) as LinearLayout
setOnTouchListener(this@BaseActionSheetView)
}, MATCH_PARENT, MATCH_PARENT, true)
.apply {
animationStyle = R.style.popwin_anim_style
setOnDismissListener { this@BaseActionSheetView.dismiss() }
inputMethodMode = PopupWindow.INPUT_METHOD_NEEDED
softInputMode = WindowManager.LayoutParams.SOFT_INPUT_ADJUST_RESIZE
}
init {
this.initBtn()
this.initCancel()
}
protected abstract fun initView(): View
protected abstract fun initBtn()
protected abstract fun initCancel()
override fun onClick(v: View?) {
when (v) {
mBtnCancel -> {
}
is TextView, is Button -> v.tag.takeIf { it is Int }?.let {
val onClickListener = list[v.tag as Int].onClickListener
onClickListener?.onClick(v)
}
else -> {
}
}
mPopupWindow.dismiss()
}
override fun onTouch(v: View?, event: MotionEvent?): Boolean {
val height: Int = mCustomContent?.top!!.toInt()
val y: Int = event?.y!!.toInt()
when (event.action) {
MotionEvent.ACTION_UP -> {
y.takeIf { it < height }.let {
println("y: $y")
println("height: $height")
mPopupWindow.dismiss()
}
}
}
return true
}
private fun dismiss() {
rootView.removeView(mFrameLayout)
}
fun setCancelText(text: String) {
this.mBtnCancel?.text = text
}
fun setCancelTextColor(color: Int) {
this.mBtnCancel?.setTextColor(color)
}
fun setCancelTextSize(size: Float) {
this.mBtnCancel?.setTextSize(TypedValue.COMPLEX_UNIT_SP, size)
}
fun hideCancel() {
this.mBtnCancel?.visibility = View.GONE
}
fun show() {
rootView.addView(mFrameLayout, MATCH_PARENT, MATCH_PARENT)
mPopupWindow.showAtLocation(mFrameLayout, Gravity.BOTTOM or Gravity.CENTER_HORIZONTAL, 0, 0)
}
/**
* 根据手机的分辨率从 dp 的单位 转成为 px(像素)
*/
protected fun dip2px(context: Context, dpValue: Float): Int {
return TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dpValue, context.resources.displayMetrics).toInt()
}
}
代码块二：ActionSheetBtnInfo.kt
/**
* Created by zyao89 on 2017/5/24.
* Contact me at 305161066@qq.com or zyao89@gmail.com
* For more projects: https://github.com/zyao89
* My Blog: http://zyao89.me
*/
data class ActionSheetBtnInfo(var text: String, var textColor: Int = DEFAULT_COLOR, var backgroundResource: Int = R.drawable.custom_view_select_pop_selector_btn) : Serializable {
companion object {
//这里可以填写单例
}
var onClickListener: View.OnClickListener? = null
/**
* 自定义get和set方法
*/
var textSize: Float? = null
get() = field
set(value) {
field = value
}
}
代码块三：ActionSheetView.kt
/**
* Created by zyao89 on 2017/5/24.
* Contact me at 305161066@qq.com or zyao89@gmail.com
* For more projects: https://github.com/zyao89
* My Blog: http://zyao89.me
*/
class ActionSheetView(context: Context, list: List<ActionSheetBtnInfo>) : BaseActionSheetView(context, list) {
override fun initView(): View {
return View.inflate(context, R.layout.custom_view_select_pop, null)
}
override fun initBtn() {
for ((index, btnInfo) in list.withIndex()) {
TextView(context)
.apply {
tag = index
text = btnInfo.text
btnInfo.textSize?.let {
setTextSize(TypedValue.COMPLEX_UNIT_SP, it)
}
height = dip2px(context, 44.0f)
gravity = Gravity.CENTER
layoutParams = ViewGroup.LayoutParams(MATCH_PARENT, dip2px(context, 44.0f))
setTextColor(btnInfo.textColor)
setBackgroundResource(btnInfo.backgroundResource)
setOnClickListener(this@ActionSheetView)
}
.also {
val layoutParams = LinearLayout.LayoutParams(MATCH_PARENT, MATCH_PARENT)
layoutParams.topMargin = dip2px(context, 5.0f)
mCustomContent?.addView(it, index, layoutParams)
}
.let {
mBtnViewList.add(it)
}
}
}
override fun initCancel() {
mBtnCancel = TextView(context)
.apply {
text = "Cancel"
height = dip2px(context, 44.0f)
gravity = Gravity.CENTER
layoutParams = ViewGroup.LayoutParams(MATCH_PARENT, dip2px(context, 44.0f))
setTextColor(if (list.isEmpty()) DEFAULT_BTN_SELECT_COLOR else list[0].textColor)
setBackgroundResource(if (list.isEmpty()) R.drawable.custom_view_select_pop_selector_btn else list[0].backgroundResource)
setOnClickListener(this@ActionSheetView)
}
.apply {
val layoutParams = LinearLayout.LayoutParams(MATCH_PARENT, MATCH_PARENT)
layoutParams.topMargin = dip2px(context, 15.0f)
layoutParams.bottomMargin = dip2px(context, 20.0f)
mCustomContent?.let {
mCustomContent?.addView(this@apply, it.childCount, layoutParams)
}
}
}
}
代码块四：ActionSheetListView.kt
/**
* Created by zyao89 on 2017/5/24.
* Contact me at 305161066@qq.com or zyao89@gmail.com
* For more projects: https://github.com/zyao89
* My Blog: http://zyao89.me
*/
class ActionSheetListView(context: Context, list: List<ActionSheetBtnInfo>) : BaseActionSheetView(context, list) {
override fun initView(): View {
return View.inflate(context, R.layout.custom_view_select_list_pop, null)
}
override fun initBtn() {
for ((index, btnInfo) in list.withIndex()) {
TextView(context)
.apply {
tag = index
text = btnInfo.text
btnInfo.textSize?.let {
setTextSize(TypedValue.COMPLEX_UNIT_SP, it)
}
height = dip2px(context, 44.0f)
gravity = Gravity.CENTER
layoutParams = ViewGroup.LayoutParams(MATCH_PARENT, dip2px(context, 44.0f))
setTextColor(btnInfo.textColor)
setBackgroundResource(R.drawable.custom_view_select_list_pop_selector_btn)
setOnClickListener(this@ActionSheetListView)
}
.also {
val layoutParams = LinearLayout.LayoutParams(MATCH_PARENT, MATCH_PARENT)
layoutParams.topMargin = 1
mCustomContent?.addView(it, index, layoutParams)
}
.let {
mBtnViewList.add(it)
}
}
}
override fun initCancel() {
mBtnCancel = TextView(context)
.apply {
text = "Cancel"
height = dip2px(context, 44.0f)
gravity = Gravity.CENTER
layoutParams = ViewGroup.LayoutParams(MATCH_PARENT, dip2px(context, 44.0f))
setTextColor(DEFAULT_BTN_CANCEL_COLOR)
setBackgroundResource(R.drawable.custom_view_select_list_pop_selector_btn)
setOnClickListener(this@ActionSheetListView)
}
.apply {
val layoutParams = LinearLayout.LayoutParams(MATCH_PARENT, MATCH_PARENT)
layoutParams.topMargin = 1
layoutParams.bottomMargin = dip2px(context, 1.0f)
mCustomContent?.let {
mCustomContent?.addView(this@apply, it.childCount, layoutParams)
}
}
}
}
布局文件Layout
layout布局一：custom_view_select_pop.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center_horizontal"
android:orientation="vertical" >
<LinearLayout
android:id="@+id/pop_layout"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:gravity="center_horizontal"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:orientation="vertical" >
</LinearLayout>
</RelativeLayout>
layout布局二：custom_view_select_list_pop.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center_horizontal"
android:orientation="vertical" >
<LinearLayout
android:id="@+id/pop_layout"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:gravity="center_horizontal"
android:orientation="vertical" >
</LinearLayout>
</RelativeLayout>
anim文件
ppwindow_show_anim.xml
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
<translate
android:duration="300"
android:fromXDelta="0"
android:toXDelta="0"
android:fromYDelta="200"
android:toYDelta="0"
/>
<alpha
android:duration="300"
android:fromAlpha="0"
android:toAlpha="1"
/>
</set>
ppwindow_hide_anim.xml
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
<translate
android:duration="200"
android:fromXDelta="0"
android:toXDelta="0"
android:fromYDelta="0"
android:toYDelta="200"
/>
<alpha
android:duration="200"
android:fromAlpha="1"
android:toAlpha="0"
/>
</set>
drawable文件
custom_view_select_list_pop_selector_btn.xml
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true" >
<shape>
<solid android:color="#cccccccc"/>
</shape>
</item>
<item>
<shape>
<solid android:color="@android:color/white"/>
</shape>
</item>
</selector>
custom_view_select_pop_selector_btn.xml
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true" >
<shape>
<solid android:color="#cccccccc"/>
<corners android:radius="10dp" />
</shape>
</item>
<item >
<shape>
<solid android:color="@android:color/white"/>
<corners android:radius="10dp"/>
</shape>
</item>
</selector>
styles.xml
<resources>
<style name="popwin_anim_style">
<item name="android:windowEnterAnimation">@anim/ppwindow_show_anim</item>
<item name="android:windowExitAnimation">@anim/ppwindow_hide_anim</item>
</style>
</resources>
演示
ActionSheetListView.png
ActionSheetView.png
GitHub源码：zyao89/ZActionSheetView
作者：Zyao89；转载请保留此行，谢谢；
个人博客：https://zyao89.cn
