Android Weekly Issue #406
A first look at AndroidX Activity Result APIs
ActivityResultContract.
有一些内置的实现可以选择: 打电话, 照相, 请求权限, StartActivityForResult等.
prepareCall方法.
官方文档中的例子:
val dial = prepareCall(Dial()) { success ->
// Handle success or failure
}
override fun onCreate(savedInstanceState: Bundle?) {
// ...
val dialButton = findViewById<Button>(R.id.dial_button)
dialButton.setOnClickListener {
// Use the Kotlin extension in activity-ktx
// passing it the number you want to dial
dial(“555-555-5555”)
}
}
测试见文档: https://developer.android.com/training/basics/intents/result#test
Jetpack Compose: State
@Model和@Composable.
Data Privacy for Android
- 请求权限
- IPC: app间.
- opt out选项.
- 清除缓存.
- log信息.
- 禁止截图.
- 加密.
- 生物认证.
关闭键盘缓存:
android:inputType="textNoSuggestions|textVisiblePassword|textFilter"
网络请求的cache.
webview的cache.
A Subtle Memory Leak - Fragment, RecyclerView and its Adapter
Fragment被onDestroyView了但是泄漏了.
Fragment中存有adapter的强引用.
解决办法:
- adapter=null
- recyclerView.adapter=null.
Make impossible states impossible
functional domain modelling.
目的: make impossible states impossible.
利用静态语言编译器来确保model都是正确的.
举例: user profile.
最后改造成这样:
data class UserProfile(
val name: UserName,
val age: Age,
val accountType: AccountType,
val contactInfo: NonEmptySet<ContactInfo>
)
其实基本思路就是为字段建立类型, 枚举或者是sealed class.
提到一个库: Arrow:
这是一个kotlin的库: https://arrow-kt.io/
github: https://github.com/arrow-kt/arrow
Speeding up the detekt task in a multi-project Gradle build
multi-project的gradle build中, detekt加速方法: 放在根目录.
Random Musings on the R Developer Preview 2
Android R的一些看法.
Unit Testing Delays, Errors & Retries with Kotlin Flows
Kotlin Flow的使用和单元测试.
runBlocking-
runBlockingTest: 可以自己控制虚拟时间.
Implementing the Motion System With Material Components for Android
The motion system还在beta阶段.
Android's Built-in ProGuard Rules: The Missing Guide
解释Android内置的proguard rules.
这篇文章强烈推荐.
Defending Your In-Background App When Android OS Kills It
模拟系统杀死App:
adb shell am kill <PACKAGE_NAME>`
这个只会杀死可以安全被杀死的进程来释放资源.
这个命令是无情杀死:
adb shell kill
Code
一个查看room数据库的工具: https://android.jlelse.eu/exploring-android-room-database-with-room-explorer-4d760fdea9de
居然是在app里显示出来了.
一个Android构架sample:
https://github.com/PatilShreyas/Foodium
用了最新的MVVM, 协程那些技术.
