cxcbupt-CSDN博客

转载 High-Order_functions_and_lambdas

Higher-Order Functions and Lambdas1Higher-Order FunctionsA higher-order function is a function that takes functions as parameters, or returns a function.fun <T, R> Collection<T>.fold( ...

2020-01-06 14:26:58 338

转载 Services overview

1 Services overviewA Service is an application component that can perform long-running operations in the background, and it doesn’t provide a user interface. Another application component can start a...

2019-10-21 22:25:03 328

原创 Vim搜索

2019-10-21 14:29:13 310

转载 Understand Tasks and Back Stack--Defining launch modes

Defining launch modesUnderstand Tasks and Back Stack--Defining launch modes1、Using the manifest file"standard" (the default mode)"singleTop""singleTask""singleInstance"2、Using Intent flagsFLAG_ACTIVIT...

2019-10-13 16:55:01 238

转载 Java PECS

extendsThe wildcard declaration ofList<? extends Number> foo3means that any of these are legal assignments:List<? extends Number> foo3 = new ArrayList<Number>(); // Number "e...

2019-06-25 16:23:13 207

原创 IntentFilter匹配规则

1、Intent typesIntent有两种类型，显式Intent和隐式Intent。使用显式Intent启动的目标组件特别明确，而隐式Intent则需要能够匹配组件在AndroidManifest.xml中声明的<intent-filter>信息。2、Intent Filter当通过隐式Intent启动Activity时，该Intent需要同时匹配Activity在...

2018-12-01 21:22:39 475

原创 Android 8.0 Oreo 形为变更之 Notification Channels

最近（2018年11月15日）在上传App升级包至Google Play时，遇到了如下问题：即：当前App的Target API Level 为25（Android 7.1.1 Nougat），要求将App的Target API Level提升到26(Android 8.0 Oreo)或以上。查阅资料发现，Google开发者在持续提高 Android 应用的安全性与性能一文中提到：...

2018-11-17 16:50:26 762

转载持续提高 Android 应用的安全性与性能

为了提升App的安全性及性能，确保每个用户都能够获取最佳体验，Google对Android应用开发者提出了一些变更：今天，我们想要和各位 Android 开发者简单说明一下三项变更，它们背后的原因，以及它们如何让 Android 设备运行得更加安全和流畅。从 2018 下半年开始，Google Play 要求新 App 和 App 更新包将目标 SDK 版本（Target SDK Ve...

2018-11-17 14:56:20 481

原创 Android Studio: Debug Android SDK Source Code

1>查看当前设备的API Level如图，设备Android版本为8.0.0。2>使用SDK Manager下载对应的Source Code注意： a、勾选右下角的“Show Package Details” b、勾选Android 8.0.0(Oreo)下面的“Sources for Android 26”，点击"OK",即可下载该版...

2018-11-13 15:25:09 798

原创 Android Bundle--ArrayMap详解

Android 四大组件：Activity、Service、ContentProvider、Broadcast Receiver。在Android App开发中，跟UI相关使用的最多的莫过于Activity了。一个Activity 启动另一个Activity时，可以使用Intent,其包含了一组方法方便携带一些参数:1、MainActivity中包含一个按钮，点击打开DetailAct...

2018-11-03 18:47:38 1071

原创 Android Platform Codenames, Versions, API Levels, and NDK Releases

The code names match the following version numbers, along with API levels and NDK releases provided for convenience:https://source.android.com/setup/start/build-numbers

2018-06-28 16:04:05 190

转载 ScrollView’s handy trick--android:fillViewport="true"

ScrollView is one of Android’s most commonly used widget and is also one of the easiest to use. When something is too big to fit on screen, drop it inside a ScrollView and you’re done. You can’t even ...

2018-03-26 17:25:34 240

转载 OK Http-Interceptors

Interceptors are a powerful mechanism that can monitor, rewrite, and retry calls. Here's a simple interceptor that logs the outgoing request and the incoming response.class LoggingInterceptor im

2018-02-06 11:24:42 485

转载 Android Architecture Components--Saving UI States

In cases where the UI data to preserve is simple and lightweight, you might use onSaveInstanceState()alone to preserve your state data. In cases where you have complex data that you want to preserve

2018-02-05 16:29:00 274

转载 Android内存泄漏总结

Android 内存泄漏总结箫鉴哥 2016-01-19 13:44:26 浏览42979 评论10android 性能优化阿里技术协会内存管理内存泄漏摘要： Android 内存泄漏总结内存管理的目的就是让我们在开发中怎么有效的避免我们的应用出现内存泄漏的问题。内存泄漏大家都不陌生了，简单粗俗的讲，就是该被释放的对象没有释放，一直被某个或某些实例所持有却不再被

2017-12-29 16:14:26 366

转载单例-双重检查锁定与延迟初始化

在java程序中，有时候可能需要推迟一些高开销的对象初始化操作，并且只有在使用这些对象时才进行初始化。此时程序员可能会采用延迟初始化。但要正确实现线程安全的延迟初始化需要一些技巧，否则很容易出现问题。比如，下面是非线程安全的延迟初始化对象的示例代码：public class UnsafeLazyInitialization {private static Instance instance;

2017-12-22 13:58:21 357

原创 OkHttp Source Code Analyse (Part one)

OkHttp An HTTP & HTTP/2 client for Android and Java applicationsFrom:http://square.github.io/okhttp/Example:OkHttpClient client = new OkHttpClient(); Request request =

2017-12-07 11:40:36 271

转载 Method References

From:https://docs.oracle.com/javase/tutorial/java/javaOO/methodreferences.htmlKinds of Method ReferencesThere are four kinds of method references:KindExampleReference to a static m

2017-11-14 15:43:39 258

转载 Syntax of Lambda Expressions

A lambda expression consists of the following:A comma-separated list of formal parameters enclosed in parentheses. The CheckPerson.test method contains one parameter, p, which represents an in

2017-11-14 10:43:09 234

转载 Android Studio--Read garbage collection messages

Sometimes when a garbage collection event occurs, they're printed to logcat.For more detail about your app's memory, use the Memory Profiler.Dalvik log messagesIn Dalvik (but not ART), every

2017-11-03 17:55:42 344

转载 TCP Connection Establishment Process: The "Three-Way Handshake"

Normal Connection Establishment: The "Three Way Handshake"To establish a connection, each device must send a SYN and receive an ACK for it from the other device. Thus, conceptually, we need to have

2017-10-20 10:54:22 631 1

转载 Java 对象初始化过程

例子里总共测试了静态代码块，普通代码块，静态成员变量，普通成员变量，构造器。分别在基类和派生类里各有一套。public class ClassLog { private static final String TAG = "ClassLog"; public static String baseFieldInit() { Loger.i(TAG, "base

2017-10-01 14:48:02 364 4

转载 display two or more logcat filters at the same time in Android Studio

up votedown votefavoriteI have declared two LOG.i such as followings in my code:Log.i("pen", pen.toString);Log.i("book", book.toString);Then I added these two filters to

2017-09-25 17:30:49 283

转载 Android Studio / Intellij Tip of the Day

Android Studio / Intellij Tip of the Day: tools:attributeIf you have ever entered some testing text in a TextView to see how it looks in the previewer, then this is for you.For any attribute in th

2017-08-24 14:06:28 1307

转载 Android Studio Tip of the Day--Breakpoints

Android Studio Tip of the Day--Breakpoints

2017-08-23 17:50:59 543

转载 Showing a Dialog Fullscreen or as an Embedded Fragment

You might have a UI design in which you want a piece of the UI to appear as a dialog in some situations, but as a full screen or embedded fragment in others (perhaps depending on whether the device is

2017-07-24 19:52:29 446

原创从fragment开始向上查找实现了某个接口的parent Fragment 或者 Activity

//从fragment开始向上查找实现了接口listenerClass的fragment或activity public T findInterfaceByClass(Fragment fragment, Class listenerClass) { if (listenerClass != null) { if (fragment != null

2017-07-24 10:25:50 492

原创 Fragment 与DialogFragment 相互之间传递数据

场景：步骤在FragmentA 中触发显示DialogFragmentB,并传递参数数据mA2B给DialogFragmentB，在DialogFragmentB获取该参数--mA2B。步骤在DialogFragmentB中对传递的参数mA2B进行一些处理得到结果mB2A，最后点击“完成”,需要将mB2A回传给FragmentA中。步骤中的数据传递如何完成呢？步骤数据传递方

2017-06-20 11:28:42 7955 3

转载你所不知道的Android Studio调试技巧

首先，来看看Android studio中为我们提供的调试面板（标准情况下）：这里写图片描述点击右上角Restore ‘Threads’View可先展示目前相关的线程信息：这里写图片描述android studio大体为我们提供了7个功能区：单步调试区断点管理区求值表达式线程帧栈区对象变量区变量观察区下面我们分别对这七

2017-05-26 16:37:58 643

原创 Android 如何快速定位当前页面是哪个Activity or Fragment

在日常需求开发中，经常碰到不太熟悉的模块，如何快速定位相应页面对应的Activity/Fragment ？ (1)查看当前Activity ：adb shell "dumpsys window w | grep name="(2)查看当前栈顶的Activity ：adb shell dumpsys activity | grep "mFocusedActivity"(3)查看当前...

2017-05-11 11:21:15 12532 4

转载 Helper class for creating pools of objects.

2017-05-04 11:34:31 322

转载 Positions in RecyclerView

Positions in RecyclerView:RecyclerView introduces an additional level of abstraction between the RecyclerView.Adapter and RecyclerView.LayoutManager to be able to detect data set changes in batc

2017-03-30 16:24:13 279

转载 Set "gravity" attribute to a RelativeLayout not working

How gravity affects the subviews is shown in the image below.I resized the widths of all the subviews so that what is happening is more clear. Note that the way RelativeLayout handle

2017-03-07 18:28:39 347

转载 Notifications --- Preserving Navigation when Starting an Activity

When you start an Activity from a notification, you must preserve the user's expected navigation experience. Clicking Back should take the user back through the application's normal work flow to the

2017-01-20 10:58:27 346

转载 Using the RecyclerView

OverviewThe RecyclerView is a new ViewGroup that is prepared to render any adapter-based view in a similar way. It is supposed to be the successor of [[ListView|Using-an-ArrayAdapter-with-ListView]] an

2017-01-17 16:40:17 1142

转载 Size, Padding and Margins

The size of a view is expressed with a width and a height. A view actually possess two pairs of width and height values.The first pair is known as measured width and measured height. These dimen

2017-01-16 15:31:11 514

原创 Google Android 原生Rom 下载地址及刷机教程--Factory Images for Nexus and Pixel Devices

Google Android 原生Rom 下载地址及刷机教程详见链接：https://developers.google.com/android/images#hammerheadkrt16m

2017-01-13 17:48:48 78656 2

转载 Broadcasts -----Security considerations and best practices

Here are some security considerations and best practices for sending and receiving broadcasts:If you don't need to send broadcasts to components outside of your app, then send and receive local

2017-01-06 11:46:22 336

转载 Requesting Permissions at Run Time

Beginning in Android 6.0 (API level 23), users grant permissions to apps while the app is running, not when they install the app.This approach streamlines the app install process, since the user doe

2016-12-29 10:34:22 328

转载 Things That Cannot Change

Sometimes a developer will make a change to an application that has surprising results when installed as an update to a previous version — shortcuts break, widgets disappear, or it can’t even be insta

2016-12-26 13:21:21 244

Android图表－－achartengine

AChartEngine is a charting library for Android applications It currently supports the following chart types: line chart area chart scatter chart time chart bar chart pie chart bubble chart doughnut chart range high low bar chart dial chart gauge combined any combination of line cubic line scatter bar range bar bubble chart cubic line chart All the above supported chart types can contain multiple series can be displayed with the X axis horizontally default or vertically and support many other custom features The charts can be built as a view that can be added to a view group or as an intent such as it can be used to start an activity ">AChartEngine is a charting library for Android applications It currently supports the following chart types: line chart area chart scatter chart time chart bar chart pie chart bubble chart doughnut chart range high low bar chart dial chart gauge combined any combination of line cubic line s [更多]

2014-10-26

空空如也

TA创建的收藏夹 TA关注的收藏夹

TA关注的人

Android图表－－achartengine

SmartUpload上传及下载

JFreeChart使用相关

DAO设计模式Demo

空空如也