当我将材质 TabLayout 与项目一起使用时，Android layout.xml UI 消失了

Question

这是错误：

java.lang.NullPointerException: Cannot invoke "android.content.res.BridgeTypedArray.setTheme(android.content.res.Resources$Theme)" because "ta" is null
    at android.content.res.Resources_Theme_Delegate.obtainStyledAttributes(Resources_Theme_Delegate.java:74)
    at android.content.res.Resources$Theme.obtainStyledAttributes(Resources.java:1631)
    at android.content.Context.obtainStyledAttributes(Context.java:874)
    at android.widget.TextView.setTextAppearance(TextView.java:3965)
    at androidx.appcompat.widget.AppCompatTextView.setTextAppearance(AppCompatTextView.java:216)
    at com.google.android.material.textview.MaterialTextView.setTextAppearance(MaterialTextView.java:106)
    at android.widget.TextView.setTextAppearance(TextView.java:3954)
    at androidx.core.widget.TextViewCompat.setTextAppearance(TextViewCompat.java:289)
    at com.google.android.material.tabs.TabLayout$TabView.updateTab(TabLayout.java:2772)
    at com.google.android.material.tabs.TabLayout$TabView.update(TabLayout.java:2801)
    at com.google.android.material.tabs.TabLayout$TabView.setTab(TabLayout.java:2713)
    at com.google.android.material.tabs.TabLayout.createTabView(TabLayout.java:1673)
    at com.google.android.material.tabs.TabLayout.newTab(TabLayout.java:956)
    at com.google.android.material.tabs.TabLayout.addTabFromItemView(TabLayout.java:824)
    at com.google.android.material.tabs.TabLayout.addViewInternal(TabLayout.java:1730)
    at com.google.android.material.tabs.TabLayout.addView(TabLayout.java:1720)
    at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:1131)
    at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:72)
    at android.view.LayoutInflater.rInflate(LayoutInflater.java:1101)
    at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:1088)
    at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:1130)
    at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:72)
    at android.view.LayoutInflater.rInflate(LayoutInflater.java:1101)
    at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:1088)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:686)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:505)
    at com.android.layoutlib.bridge.impl.RenderSessionImpl.inflate(RenderSessionImpl.java:353)
    at com.android.layoutlib.bridge.Bridge.createSession(Bridge.java:450)
    at com.android.tools.idea.layoutlib.LayoutLibrary.createSession(LayoutLibrary.java:122)
    at com.android.tools.idea.rendering.RenderTask.createRenderSession(RenderTask.java:727)
    at com.android.tools.idea.rendering.RenderTask.lambda$inflate$9(RenderTask.java:884)
    at com.android.tools.idea.rendering.RenderExecutor$runAsyncActionWithTimeout$3.run(RenderExecutor.kt:195)
    at com.android.tools.idea.rendering.RenderExecutor$PriorityRunnable.run(RenderExecutor.kt:293)
    at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.base/java.lang.Thread.run(Unknown Source)

材质组件依赖版本：com.google.android.material:material:1.8.0

Answer 1

显然，这是一个仍需要解决的错误，选项卡布局将在设备/模拟器上完美显示，只是不会显示在 xml 文件的设计视图中。因此，选项卡布局本身没有问题，只需在设计视图中呈现它即可。在这种情况下，每次进行更改时都必须运行该应用程序来检查它，这确实浪费了很多时间，但这就是我们目前所能做的。

编辑：

我现在实际上已经弄清楚了，显然，只有当您将 tabItem 添加到 tabLayout 中时，问题才会出现。这样您就可以注释掉所有选项卡项目，完成您的工作，然后将它们注释掉并运行应用程序。