小编Moh*_*dva的帖子

我使用tablayout创建了30个可滚动的选项卡.

因此,屏幕上可以看到前三个选项卡,其余部分是不可见的,可以使用滑动手势滚动.

问题是当我以编程方式选择最后一个选项卡但它不可见时(选项卡布局不会滚动到最后一个选项卡).

如何使tablayout滚动到最后一个标签？

当我使用代码覆盖率运行单元测试时，在代码覆盖率报告中 lambda 显示为未覆盖。

下面是我的代码：

open class CoroutineContextProvider {
    open val main: CoroutineContext by lazy { Dispatchers.Main }
    open val io: CoroutineContext by lazy { Dispatchers.IO }
}

class Hello (
    private val contextProvider: CoroutineContextProvider
) {
    private val mScope = CoroutineScope(contextProvider.main)

    var value: Int = 0

    fun test() {
        mScope.launch(contextProvider.io) {
            println("THIS LINE IS NOT COVERED IN CODE COVERAGE.")
            value++
        }
    }
}

class TestCoroutineContextProvider: CoroutineContextProvider() {
    override val main: CoroutineContext
        get() = Dispatchers.Unconfined
    override val io: CoroutineContext
        get() = …

我正在尝试使用ContraintsLayout创建布局.

在我的布局中,我添加了横向GuideLine.

但是,当我运行该应用程序时,它崩溃了,如果我删除GuideLine它的工作原理.

我还查了一下APK,还有一堂课 java.awt.Rectagle

StackStrace

java.lang.NoClassDefFoundError: Failed resolution of: Ljava/awt/Rectangle;
 at android.support.constraint.solver.widgets.Guideline.<init>(Guideline.java:43)
 at android.support.constraint.ConstraintLayout.setChildrenConstraints(ConstraintLayout.java:128)
 at android.support.constraint.ConstraintLayout.updateHierarchy(ConstraintLayout.java:106)
 at android.support.constraint.ConstraintLayout.onFinishInflate(ConstraintLayout.java:87)
 at android.view.LayoutInflater.rInflate(LayoutInflater.java:867)
 at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:821)
 at android.view.LayoutInflater.inflate(LayoutInflater.java:518)
 at android.view.LayoutInflater.inflate(LayoutInflater.java:426)
 at android.view.LayoutInflater.inflate(LayoutInflater.java:377)
 at android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:280)
 at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:140)
 at com.infostretch.app.MainActivity.onCreate(MainActivity.java:11)
 at android.app.Activity.performCreate(Activity.java:6669)
 at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
 at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2578)
 at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2686)
 at android.app.ActivityThread.-wrap12(ActivityThread.java)
 at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1440)
 at android.os.Handler.dispatchMessage(Handler.java:102)
 at android.os.Looper.loop(Looper.java:154)
 at android.app.ActivityThread.main(ActivityThread.java:5969)
 at java.lang.reflect.Method.invoke(Native Method)
 at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:801)
 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:691)
Caused by: java.lang.ClassNotFoundException: Didn't find class "java.awt.Rectangle" on path: DexPathList[[zip file "/data/app/com.infostretch.app-1/base.apk"],nativeLibraryDirectories=[/data/app/com.infostretch.app-1/lib/x86_64, /system/lib64, /vendor/lib64]]
 at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56) …

在我的Android项目(Kotlin)中,我想为我的DATA LAYER使用Room持久性库.

但是当我为Room Persistent库添加依赖项时,突然构建项目开始失败.

我收到的错误:

这是我的项目级 build.gradle

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {
    ext {
        globalCompileSdkVersion = 26
        globalMinSdkVersion = 19
        globalTargetSdkVersion = 26

        kotlin_version = '1.2.10'
        support_version = "27.0.2"
        constraint_layout_version = "1.0.2"
        view_animator_version = "1.0.5"
        junit_version = "4.12"
        runner_version = "1.0.1"
        espresso_core_version = "3.0.1"
        room_version = "1.0.0"
        dagger_version = "2.13"
        rxJavaVersion = "2.1.7"
        rxAndroidVersion = "2.0.1"

        libs = [
                appCompatV7 : "com.android.support:appcompat-v7:$support_version",
                rxJava      : "io.reactivex.rxjava2:rxjava:$rxJavaVersion",
                rxAndroid …