前言
日常开发中,dialog是常见的功能,我们时常需要弹出来一些弹框提示用户
今天就定义了一个方便的dialog基类BaseSimpleDialogFragment,
支持快速地显示一个dialog
主要功能有:
initAnimation:设置入场和出场动画
getGravity:设置dialog显示位置(屏幕上,中,下)
getCanceledOnTouchOutside:点击空白处关闭
getWindowWidth
getWindowHeight
getPaddingLeft:动态设置宽高和间距
整体来说比较简单,也方便扩展
创建dialog的时候只需要实现BaseSimpleDialogFragment即可
比如这样:
class MyDialog: BaseSimpleDialogFragment() {override val layoutId: Int = R.layout.dialog_my_showcompanion object {@JvmStaticfun newInstance(): MyDialog {val dialog = MyDialog()dialog.arguments = Bundle().apply {
// putParcelableArrayList(DATA, data)}return dialog}}override fun initData() {
// data = arguments?.getParcelableArrayList(DATA) ?: return}override fun initView(view: View) {layoutView.findViewById<Button>(R.id.cancle).setOnClickListener {dismissAllowingStateLoss()}}
}
展示的时候几行代码就可以了:
MyDialog.newInstance().apply {//传递数据}.show(supportFragmentManager)
源码
源码这边先贴出来:
abstract class BaseSimpleDialogFragment : DialogFragment() {abstract val layoutId: Intprotected open fun initView(view: View) {//sonar}protected open fun initData() {//sonar}protected open fun initListener() {//sonar}lateinit var layoutView: Viewprotected lateinit var mContext: Contextoverride fun onAttach(context: Context) {super.onAttach(context)mContext = context}override fun onCreate(savedInstanceState: Bundle?) {super.onCreate(savedInstanceState)initAnimation()}override fun onCreateView(inflater: LayoutInflater,container: ViewGroup?,savedInstanceState: Bundle?): View? {layoutView = inflater.inflate(layoutId, container, false)return layoutView}override fun onViewCreated(view: View, savedInstanceState: Bundle?) {super.onViewCreated(view, savedInstanceState)initView(view)initListener()initData()}override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {val dialog = super.onCreateDialog(savedInstanceState).apply {window?.run {decorView.setPadding(getPaddingLeft(),getPaddingTop(),getPaddingRight(),getPaddingBottom())val wlp = attributes.apply {gravity = getGravity()width = getWindowWidth()height = getWindowHeight()}attributes = wlpsetWindowParam(this)}setCanceledOnTouchOutside(getCanceledOnTouchOutside())}isCancelable = getCancelable()return dialog}protected open fun setWindowParam(window: Window) {//sonar }protected open fun initAnimation() {if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {setStyle(STYLE_NORMAL, R.style.FragmentDialogStyleWithAni)} else {setStyle(STYLE_NORMAL, R.style.FragmentDialogStyle_Low_Level_WithAni)}}protected open fun getGravity(): Int {return Gravity.CENTER}protected open fun getWindowWidth(): Int {return WindowManager.LayoutParams.MATCH_PARENT}protected open fun getWindowHeight(): Int {return WindowManager.LayoutParams.WRAP_CONTENT}protected open fun getPaddingLeft(): Int {return 0}protected open fun getPaddingRight(): Int {return 0}protected open fun getPaddingTop(): Int {return 0}protected open fun getPaddingBottom(): Int {return 0}protected open fun getCanceledOnTouchOutside(): Boolean {return false}protected open fun getCancelable(): Boolean {return true}override fun dismiss() {dismissAllowingStateLoss()}open fun show(manager: FragmentManager) {show(manager, javaClass.simpleName)}override fun show(manager: FragmentManager, tag: String?) {try {super.show(manager, tag)} catch (e: Exception) {Log.e("print", "show: $e")}}}
用到的style:
<style name="FragmentDialogStyleWithAni" parent="FragmentDialogStyle"><item name="android:windowAnimationStyle">@style/DialogAnimation</item></style><style name="FragmentDialogStyle_Low_Level_WithAni" parent="FragmentDialogStyle_Low_Level"><item name="android:windowAnimationStyle">@style/DialogAnimation</item></style><style name="DialogAnimation" parent="@android:style/Animation.Dialog"><item name="android:windowEnterAnimation">@anim/push_ani_up_in</item><item name="android:windowExitAnimation">@anim/push_ani_down_out</item></style><style name="FragmentDialogStyle_Low_Level" parent="android:Theme.Holo.Light.Dialog"><item name="android:windowBackground">@android:color/transparent</item><item name="android:windowFrame">@null</item><item name="android:backgroundDimEnabled">true</item><item name="android:windowIsTranslucent">false</item><item name="android:windowNoTitle">true</item><item name="android:windowContentOverlay">@null</item></style><style name="FragmentDialogStyle" parent="Base.AlertDialog.AppCompat.Light"><!--点击窗口外是否消失--><item name="android:windowCloseOnTouchOutside">true</item><!-- 背景颜色及透明程度 --><item name="android:windowBackground">@android:color/transparent</item><!-- 是否半透明 --><item name="android:windowIsTranslucent">false</item><!-- 是否没有标题 --><item name="android:windowNoTitle">true</item><!-- 是否浮现在activity之上 设置成false则match_parent可以全屏--><item name="android:windowIsFloating">true</item></style>
还有两个默认的进入和退出动画
<?xml version="1.0" encoding="UTF-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"><translateandroid:duration="500"android:fromYDelta="0"android:toYDelta="100%p" />
</set>
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"><translateandroid:duration="500"android:fromYDelta="100%p"android:toYDelta="0" />
</set>
内存泄漏
在使用这个自定义的dialog的时候
我发现退出页面时
LeakCanary 会在dialog dismiss后报内存泄漏
大概像这样:
代码很简单,贴出来:
class MainActivity : AppCompatActivity() {lateinit var mydialog: MyDialog@SuppressLint("MissingInflatedId")override fun onCreate(savedInstanceState: Bundle?) {super.onCreate(savedInstanceState)setContentView(R.layout.activity_main)findViewById<Button>(R.id.showbtn).setOnClickListener {mydialog = MyDialog.newInstance().apply {//传递数据}mydialog.show(supportFragmentManager)}}
}
dialog内部有按钮,点击就关闭dialog:
layoutView.findViewById<Button>(R.id.cancle).setOnClickListener {dismissAllowingStateLoss()}
不知道大家看出来原因没有
看LeakCanary 日志,告诉我的是dialogFragment 收到了onDestroy的回调了。
也就是被销毁,那么gc就应该回收掉该fragment对象。
但是呢当前界面还持有该对象的引用造成了内存泄漏。
我们点进dismissAllowingStateLoss的源码
可以看到:dismissAllowingStateLoss应该是要去remove这个fragment,
但是如果activity持有的话,就无法被内存回收了,从而导致了内存泄漏
解决
解决办法也很简单,提供几种方法:
1:简单粗暴,dismiss的时候,把Activity的引用置位null
首先我们的kotlin代码就要改下:
var mydialog: MyDialog?=null
然后dismiss的时候,把Activity的引用置位null
mydialog=nullmydialog?.dismiss()
2:创建一个一次性的对象来使用,也就是局部变量,让当前界面不再全局持有该dialog对象。
findViewById<Button>(R.id.showbtn).setOnClickListener {var mydialog = MyDialog.newInstance().apply {//传递数据}mydialog.show(supportFragmentManager)}
3:弱引用dialog,利用弱引用的特性,确保内存可以顺利回收
class MainActivity : AppCompatActivity() {lateinit var mydialog: WeakReference<MyDialog>@SuppressLint("MissingInflatedId")override fun onCreate(savedInstanceState: Bundle?) {super.onCreate(savedInstanceState)setContentView(R.layout.activity_main)findViewById<Button>(R.id.showbtn).setOnClickListener {mydialog = WeakReference(MyDialog.newInstance().apply {//传递数据})mydialog.get()?.show(supportFragmentManager)}}
}
关于自定义DialogFragment以及解决内存泄漏的问题,就介绍到这了。