我完成了这一步骤并解决了大部分问题，但是有一个问题我无法解决。进行了搜索并试图弄清结果，尝试了一些方法但仍然没有进展。问题似乎与应用程序中的样式/主题有关。
堆栈跟踪
Process: net.myapp.app.debug, PID: 14927
java.lang.RuntimeException: Unable to start activity ComponentInfo{net.myapp.app.debug/net.myapp.app.ui.SplashSreenActivity}: android.view.InflateException: Binary XML file line #31: Binary XML file line #31: Error inflating class android.widget.TextView
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2817)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6541)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
Caused by: android.view.InflateException: Binary XML file line #31: Binary XML file line #31: Error inflating class android.widget.TextView
Caused by: android.view.InflateException: Binary XML file line #31: Error inflating class android.widget.TextView
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Constructor.newInstance0(Native Method)
at java.lang.reflect.Constructor.newInstance(Constructor.java:334)
at android.view.LayoutInflater.createView(LayoutInflater.java:647)
at com.android.internal.policy.PhoneLayoutInflater.onCreateView(PhoneLayoutInflater.java:58)
at android.view.LayoutInflater.onCreateView(LayoutInflater.java:720)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:788)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:730)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:863)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:866)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824)
at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
at android.view.LayoutInflater.inflate(LayoutInflater.java:374)
at com.android.internal.policy.PhoneWindow.setContentView(PhoneWindow.java:418)
at android.app.Activity.setContentView(Activity.java:2654)
at net.shopayard.app.ui.SplashSreenActivity.onCreate(SplashSreenActivity.java:42)
at android.app.Activity.performCreate(Activity.java:6975)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1213)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2770)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6541)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
Caused by: java.lang.UnsupportedOperationException: Failed to resolve attribute at index 6: TypedValue{t=0x2/d=0x101009b a=1}
at android.content.res.TypedArray.getColorStateList(TypedArray.java:538)
at android.widget.TextView.<init>(TextView.java:904)
at android.widget.TextView.<init>(TextView.java:818)
at android.widget.TextView.<init>(TextView.java:814)
at java.lang.reflect.Constructor.newInstance0(Native Method)
at java.lang.reflect.Constructor.newInstance(Constructor.java:334)
at android.view.LayoutInflater.createView(LayoutInflater.java:647)
at com.android.internal.policy.PhoneLayoutInflater.onCreateView(PhoneLayoutInflater.java:58)
at android.view.LayoutInflater.onCreateView(LayoutInflater.java:720)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:788)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:730)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:863)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:866)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824)
at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
at android.view.LayoutInflater.inflate(LayoutInflater.java:374)
at com.android.internal.policy.PhoneWindow.setContentView(PhoneWindow.java:418)
at android.app.Activity.setContentView(Activity.java:2654)
at net.myapp.app.ui.SplashSreenActivity.onCreate(SplashSreenActivity.java:42)
at android.app.Activity.performCreate(Activity.java:6975)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1213)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2770)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6541)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
build.grade(应用程序)
apply plugin: 'com.android.application'
android {
signingConfigs {
debug {
storeFile file('C:/Users/myapp/.android/debug.keystore')
}
}
compileSdkVersion 28
buildToolsVersion "28.0.3"
defaultConfig {
applicationId "net.myapp.app"
minSdkVersion 21
targetSdkVersion 28
versionCode 22
versionName '3.0.0'
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
debug {
applicationIdSuffix '.debug'
versionNameSuffix '.debug'
}
}
packagingOptions {
exclude 'META-INF/DEPENDENCIES'
exclude 'META-INF/NOTICE'
exclude 'META-INF/LICENSE'
}
repositories {
flatDir {
dirs 'libs'
}
}
productFlavors {
}
useLibrary 'org.apache.http.legacy'
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
compile 'com.android.support:appcompat-v7:28.0.0'
compile 'com.android.support:recyclerview-v7:28.0.0'
compile 'com.android.support:cardview-v7:28.0.0'
compile 'com.viewpagerindicator:library:2.4.1'
compile 'com.android.support:support-v4:28.0.0'
compile 'com.astuetz:pagerslidingtabstrip:1.0.1'
compile 'com.davemorrissey.labs:subsampling-scale-image-view:2.3.0'
compile('org.apache.httpcomponents:httpmime:4.3.6') {
exclude module: 'httpclient'
}
compile 'org.apache.httpcomponents:httpclient-android:4.3.5'
compile(name: 'analyticslibrary', ext: 'aar')
compile 'com.google.android.gms:play-services-analytics:16.0.4'
}
样式.xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
<item name="windowActionBar">false</item>
<item name="drawerArrowStyle">@style/DrawerArrowStyle</item>
<item name="colorPrimary">@color/primary_color</item>
<item name="colorPrimaryDark">@color/primary_color_dark</item>
<item name="colorAccent">@color/accent</item>
<item name="actionBarSize">@dimen/abc_action_bar_default_height_material</item>
<item name="colorSwitchThumbNormal">@color/switch_thumb_normal</item>
</style>
<style name="ToolbarThemeOverlay" parent="ThemeOverlay.AppCompat.Dark.ActionBar">
<item name="android:subtitleTextStyle">@style/SubTitleTextStyle</item>
<item name="subtitleTextStyle">@style/SubTitleTextStyle</item>
</style>
<style name="SubTitleTextStyle">
<item name="android:textStyle">italic</item>
<item name="android:textSize">12sp</item>
<item name="android:textColor">@color/text_white</item>
</style>
<style name="DrawerArrowStyle" parent="Widget.AppCompat.DrawerArrowToggle">
<item name="spinBars">true</item>
<item name="color">@android:color/white</item>
</style>
<style name="SpinnerButton">
<item name="android:minHeight">40dp</item>
<item name="android:layout_marginLeft">@dimen/content_margin_normal</item>
<item name="android:layout_marginRight">@dimen/content_margin_normal</item>
<item name="android:background">@drawable/spinner_button_selector</item>
<item name="android:textColor">@color/text_black</item>
<item name="android:textSize">@dimen/text_size_medium</item>
<item name="android:textStyle">italic</item>
</style>
<style name="EditTextRectangleStyle">
<item name="android:layout_marginLeft">@dimen/content_margin_normal</item>
<item name="android:layout_marginRight">@dimen/content_margin_normal</item>
<item name="android:background">@drawable/black_rectangle</item>
<item name="android:textColor">@color/text_black</item>
<item name="android:textSize">@dimen/text_size_medium</item>
<item name="android:textColorHint">@color/text_gray</item>
<item name="android:textStyle">italic</item>
</style>
<style name="EditTextStyle">
<item name="android:minHeight">40dp</item>
<item name="android:layout_marginLeft">@dimen/content_margin_normal</item>
<item name="android:layout_marginRight">@dimen/content_margin_normal</item>
<item name="android:background">@drawable/edittext_bg</item>
<item name="android:textColor">@color/text_black</item>
<item name="android:textSize">@dimen/text_size_medium</item>
<item name="android:textColorHint">@color/text_gray</item>
<item name="android:textStyle">italic</item>
</style>
<style name="EditTextNoMarginsStyle">
<item name="android:minHeight">40dp</item>
<item name="android:background">@drawable/edittext_bg</item>
<item name="android:textColor">@color/text_black</item>
<item name="android:textSize">@dimen/text_size_medium</item>
<item name="android:textColorHint">@color/text_gray</item>
<item name="android:textStyle">italic</item>
</style>
<style name="FormLabelClickable" parent="FormLabelStyle">
<item name="android:clickable">true</item>
<item name="android:textColor">@color/clickable_black_text</item>
</style>
<style name="FormLabelStyle">
<item name="android:minHeight">40dp</item>
<item name="android:layout_marginLeft">@dimen/content_margin_normal</item>
<item name="android:layout_marginRight">@dimen/content_margin_normal</item>
<item name="android:gravity">center_vertical</item>
<item name="android:textColor">@color/text_black</item>
<item name="android:textSize">@dimen/text_size_medium</item>
<item name="android:textStyle">italic</item>
</style>
<style name="StandardSwitch" parent="FormLabelStyle" >
<item name="android:padding">1dp</item>
<item name="android:textColor">@color/switch_text_dark_gray</item>
</style>
<style name="SwitchLabelStyle">
<item name="android:paddingRight">@dimen/content_margin_normal</item>
<item name="android:textColor">@color/text_gray</item>
<item name="android:textSize">@dimen/text_size_small</item>
</style>
<style name="CustomTabPageIndicator">
<item name="android:background">@color/primary_color</item>
<item name="android:textSize">12sp</item>
<item name="pstsTextAllCaps">true</item>
<item name="android:maxLines">1</item>
<item name="android:textColor">#FFAAAAAA</item>
<item name="pstsIndicatorColor">#FFFFFF</item>
<item name="pstsDividerColor">@android:color/transparent</item>
<item name="pstsShouldExpand">true</item>
<item name="pstsIndicatorHeight">4dp</item>
<item name="pstsTabPaddingLeftRight">1dp</item>
<item name="pstsUnderlineColor">#FFFFFF</item>
<item name="pstsUnderlineHeight">0dp</item>
</style>
<style name="ButtonBar">
<item name="android:paddingLeft">2dp</item>
<item name="android:paddingTop">5dp</item>
<item name="android:paddingRight">2dp</item>
<item name="android:paddingBottom">0dp</item>
<item name="android:background">@android:drawable/bottom_bar</item>
</style>
<style name="dialog_popup_slideout">
<item name="android:windowExitAnimation">@anim/slide_out_dialog</item>
</style>
<style name="dialog_slidein_slideout">
<item name="android:windowEnterAnimation">@anim/slide_in_dialog</item>
</style>
<style name="dialog_slidein_left_slideout">
<item name="android:windowEnterAnimation">@anim/slide_in_left</item>
<item name="android:windowExitAnimation">@anim/slide_out_dialog</item>
</style>
<style name="ButtonBarButton" />
<style name="FullscreenTheme" parent="android:Theme.NoTitleBar">
<item name="android:windowContentOverlay">@null</item>
<item name="android:windowBackground">@null</item>
<item name="metaButtonBarStyle">@style/ButtonBar</item>
<item name="metaButtonBarButtonStyle">@style/ButtonBarButton</item>
</style>
<style name="FullscreenTheme.NoActionBar" parent="ThemeOverlay.AppCompat.Dark.ActionBar">
<item name="android:windowContentOverlay">@null</item>
<item name="android:windowBackground">@null</item>
<item name="metaButtonBarStyle">@style/ButtonBar</item>
<item name="metaButtonBarButtonStyle">@style/ButtonBarButton</item>
<item name="android:windowActionBar">false</item>
<item name="android:windowNoTitle">true</item>
<item name="android:windowIsFloating">false</item>
</style>
<style name="NumberPickerDialog" parent="DialogCenteredTitle">
<item name="android:layout_width">280dp</item>
</style>
<style name="DialogCenteredTitle" parent="Base.Theme.AppCompat.Light.Dialog">
<item name="android:windowTitleStyle">@style/CenteredTitle</item>
<item name="colorAccent">@color/accent</item>
<item name="android:windowBackground">@android:color/transparent</item>
<item name="android:windowFrame">@null</item>
<item name="android:windowContentOverlay">@null</item>
<item name="android:colorBackgroundCacheHint">@null</item>
</style>
<style name="CenteredTitle" parent="Base.TextAppearance.AppCompat.Title">
<item name="android:gravity">center</item>
<item name="android:layout_width">match_parent</item>
<item name="android:layout_gravity">center</item>
<item name="android:layout_marginBottom">8dp</item>
</style>
<style name="RedRectangularButton" parent="BlueRectangularButton">
<item name="android:background">@drawable/red_rectangle_button_bg_selector</item>
</style>
<style name="BlueRectangularButton">
<item name="android:minHeight">40dp</item>
<item name="android:paddingLeft">@dimen/rectangular_button_horizontal_margin</item>
<item name="android:paddingRight">@dimen/rectangular_button_horizontal_margin</item>
<item name="android:textColor">@color/button_text_white</item>
<item name="android:background">@drawable/blue_rectangle_button_bg_selector</item>
<item name="android:textAllCaps">true</item>
</style>
<style name="ImageViewAttachment">
<item name="android:width">0dp</item>
<item name="android:minHeight">@dimen/select_image_min_height</item>
<item name="android:scaleType">fitCenter</item>
<item name="android:background">@drawable/dashed_rectangle_selector</item>
<item name="android:layout_weight">0.25</item>
<item name="android:src">@drawable/symbol_camera</item>
<item name="android:adjustViewBounds">true</item>
</style>
</resources>
Activity .xml
<RelativeLayout 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:background="@color/splash_background"
tools:context="net.myapp.app.ui.SplashSreenActivity">
<ImageView
android:id="@+id/image"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:src="@drawable/image_menu"
android:layout_alignParentBottom="true"
android:adjustViewBounds="true"
android:scaleType="fitEnd"/>
<ProgressBar
android:id="@+id/progressBar"
style="?android:attr/progressBarStyleLarge"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:visibility="gone"/>
<LinearLayout
android:id="@+id/layoutError"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:gravity="center_horizontal"
android:paddingBottom="100dp"
android:orientation="vertical"
android:visibility="gone">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="16dp"
android:textColor="@color/text_black"
android:gravity="center_horizontal"
android:textSize="16sp"
android:text="@string/error_maintenance"/>
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="@dimen/content_margin_normal">
<Button
android:id="@+id/buttonRetry"
android:layout_width="60dp"
android:layout_height="60dp"
android:textColor="@color/text_white"
android:textSize="12sp"
android:text="@string/retry"
android:background="@drawable/circle_button_blue_selector"/>
<ProgressBar
android:id="@+id/progressBarRetry"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
style="?android:attr/progressBarStyleSmall"
android:layout_centerInParent="true"
android:visibility="invisible"/>
</RelativeLayout>
</LinearLayout>
</RelativeLayout>
字符串.xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="app_name">myapp</string>
<string name="ic_action_search">Search</string>
<string name="ic_action_profile">Profile</string>
<string name="ic_action_refresh">Refresh</string>
<string name="action_call">Call</string>
<string name="action_email">Email</string>
<string name="action_share">Share</string>
<string name="action_location">Location</string>
<string name="action_report">Report</string>
<string name="navigation_drawer_open">Open navigation drawer</string>
<string name="navigation_drawer_close">Close navigation drawer</string>
<string name="action_settings">Settings</string>
<string name="hello_blank_fragment">Hello blank fragment</string>
<string name="register_below">Register below to receive deals and promotions from local businesses.</string>
<string name="gender">Gender</string>
<string name="birth_year">Year of birth</string>
<string name="island">Island</string>
<string name="button_done">Done</string>
<string name="button_ok">OK</string>
<string name="loading">Loading...</string>
<string name="title_activity_profile">Profile</string>
<string name="title_activity_deals_details">DealsDetailsActivity</string>
<string name="title_activity_fullscreen_image">FullscreenImageActivity</string>
<string name="title_activity_classified_details">ClassifiedDetailsActivity</string>
<string name="title_activity_splash_sreen">SplashSreenActivity</string>
<!-- Splash screen -->
<string name="retry">Retry</string>
<string name="retry_failed">Retry failed</string>
<string name="error_maintenance">The servers are currently undergoing maintenance, please try again in a few minutes.</string>
</resources>
颜色.xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
<color name="primary_color_clicked">#0071a8</color>
<color name="primary_color">#004A77</color>
<color name="primary_color_dark">#004368</color>
<color name="switch_thumb_normal">#004A77</color>
<color name="switch_text_dark_gray">#464646</color>
<color name="accent">#80A4BB</color>
<color name="orange">#EA5C04</color>
<color name="dark_red">#A00809</color>
<color name="red_divider">#A91F20</color>
<color name="line_light_gray">#D9D9D9</color>
<color name="text_blue">#004A77</color>
<color name="text_white">#FFFFFF</color>
<color name="text_gray">#969696</color>
<color name="text_content_dark">#333</color>
<color name="text_dark_red">#980000</color>
<color name="tab_text_inactive">#98b6c8</color>
<color name="text_orange">#E74700</color>
<color name="text_black">#111111</color>
<color name="text_black_focused">#888888</color>
<color name="button_blue">#004A77</color>
<color name="button_blue_focused">#0075BA</color>
<color name="menu_list_divider">#9DD0F5</color>
<color name="menu_selected_item_background">#D6EDFF</color>
<color name="black_overlay">#66000000</color>
<color name="search_background">#A7D9FE</color>
<color name="splash_background">#A6D8FD</color>
<color name="darken_filter_color">#22000000</color>
<color name="classified_id_background">#DDDDDD</color>
<color name="red_button">#A00809</color>
<color name="red_button_focused">#f40809</color>
</resources>
这个问题似乎与 FullscreenTheme 或 FullscreenTheme.NoActionBar 有关，因为我一直在测试不同的方法，并且在更改这些方法时得到了不同的堆栈跟踪。然而，上面的代码在 SDK 21 中运行良好。我觉得训练有素的眼睛会立即发现问题，但遗憾的是我不是日常程序员。
最佳答案
它清楚地表明找不到@string/error_maintenance。
尝试clean project 并查看它是否具有名为 error_maintenance 的 String 资源。
此外，之前，在我的项目中，我能够创建一个带有“error.maintenance”之类的点的字符串资源，并使用 @string/error_maintenance 调用它。
从 api 28 开始，我不得不删除 strings.xml 中的每个点
关于java - 从 SDK 21 迁移到 SDK 28，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/53240046/
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我只想对我一直在思考的这个问题有其他意见，例如我有classuser_controller和classuserclassUserattr_accessor:name,:usernameendclassUserController//dosomethingaboutanythingaboutusersend问题是我的User类中是否应该有逻辑user=User.newuser.do_something(user1)oritshouldbeuser_controller=UserController.newuser_controller.do_something(user1,user2)我
什么是ruby的rack或python的Java的wsgi？还有一个路由库。 最佳答案 来自Python标准PEP333:Bycontrast,althoughJavahasjustasmanywebapplicationframeworksavailable,Java's"servlet"APImakesitpossibleforapplicationswrittenwithanyJavawebapplicationframeworktoruninanywebserverthatsupportstheservletAPI.ht
这篇文章是继上一篇文章“Observability：从零开始创建Java微服务并监控它（一）”的续篇。在上一篇文章中，我们讲述了如何创建一个Javaweb应用，并使用Filebeat来收集应用所生成的日志。在今天的文章中，我来详述如何收集应用的指标，使用APM来监控应用并监督web服务的在线情况。源码可以在地址 https://github.com/liu-xiao-guo/java_observability 进行下载。摄入指标指标被视为可以随时更改的时间点值。当前请求的数量可以改变任何毫秒。你可能有1000个请求的峰值，然后一切都回到一个请求。这也意味着这些指标可能不准确，你还想提取最小/
HashMap中为什么引入红黑树，而不是AVL树呢1.概述开始学习这个知识点之前我们需要知道，在JDK1.8以及之前，针对HashMap有什么不同。JDK1.7的时候，HashMap的底层实现是数组+链表JDK1.8的时候，HashMap的底层实现是数组+链表+红黑树我们要思考一个问题，为什么要从链表转为红黑树呢。首先先让我们了解下链表有什么不好？？？2.链表上述的截图其实就是链表的结构，我们来看下链表的增删改查的时间复杂度增：因为链表不是线性结构，所以每次添加的时候，只需要移动一个节点，所以可以理解为复杂度是N(1)删：算法时间复杂度跟增保持一致查：既然是非线性结构，所以查询某一个节点的时候
遍历文件夹我们通常是使用递归进行操作，这种方式比较简单，也比较容易理解。本文为大家介绍另一种不使用递归的方式，由于没有使用递归，只用到了循环和集合，所以效率更高一些！一、使用递归遍历文件夹整体思路1、使用File封装初始目录，2、打印这个目录3、获取这个目录下所有的子文件和子目录的数组。4、遍历这个数组，取出每个File对象4-1、如果File是否是一个文件，打印4-2、否则就是一个目录，递归调用代码实现publicclassSearchFile{publicstaticvoidmain(String[]args){//初始目录Filedir=newFile("d:/Dev");Datebeg
我基本上来自Java背景并且努力理解Ruby中的模运算。(5%3)(-5%3)(5%-3)(-5%-3)Java中的上述操作产生，2个-22个-2但在Ruby中，相同的表达式会产生21个-1-2.Ruby在逻辑上有多擅长这个？模块操作在Ruby中是如何实现的？如果将同一个操作定义为一个web服务，两个服务如何匹配逻辑。 最佳答案 在Java中，模运算的结果与被除数的符号相同。在Ruby中，它与除数的符号相同。remainder()在Ruby中与被除数的符号相同。您可能还想引用modulooperation.
Java的Collections.unmodifiableList和Collections.unmodifiableMap在Ruby标准API中是否有等价物？ 最佳答案 使用freeze应用程序接口(interface):Preventsfurthermodificationstoobj.ARuntimeErrorwillberaisedifmodificationisattempted.Thereisnowaytounfreezeafrozenobject.SeealsoObject#frozen?.Thismethodretur