android - 无法膨胀 MaterialCardView

Question

我收到以下错误:

    E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.example.mainapp, PID: 21456
    android.view.InflateException: Binary XML file line #11: Binary XML file line #11: Error inflating class <unknown>
    Caused by: android.view.InflateException: Binary XML file line #11: Error inflating class <unknown>
    Caused by: java.lang.reflect.InvocationTargetException
        at java.lang.reflect.Constructor.newInstance0(Native Method)
        at java.lang.reflect.Constructor.newInstance(Constructor.java:343)
        at android.view.LayoutInflater.createView(LayoutInflater.java:658)
        at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:827)
        at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:750)
        at android.view.LayoutInflater.rInflate(LayoutInflater.java:900)
        at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:861)
        at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
        at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
        at com.example.mainapp.ListCategories$MyAdapter.getView(ListCategories.java:99)
        at android.widget.AbsListView.obtainView(AbsListView.java:2413)
        at android.widget.ListView.makeAndAddView(ListView.java:2074)
        at android.widget.ListView.fillDown(ListView.java:801)
        at android.widget.ListView.fillFromTop(ListView.java:862)
        at android.widget.ListView.layoutChildren(ListView.java:1841)
        at android.widget.AbsListView.onLayout(AbsListView.java:2212)
        at android.view.View.layout(View.java:21112)
        at android.view.ViewGroup.layout(ViewGroup.java:6400)
        at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1828)
        at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1656)
        at android.widget.LinearLayout.onLayout(LinearLayout.java:1565)
        at android.view.View.layout(View.java:21112)
        at android.view.ViewGroup.layout(ViewGroup.java:6400)
        at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
        at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
        at android.view.View.layout(View.java:21112)
        at android.view.ViewGroup.layout(ViewGroup.java:6400)
        at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1828)
        at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1656)
        at android.widget.LinearLayout.onLayout(LinearLayout.java:1565)
        at android.view.View.layout(View.java:21112)
        at android.view.ViewGroup.layout(ViewGroup.java:6400)
        at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
        at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
        at android.view.View.layout(View.java:21112)
        at android.view.ViewGroup.layout(ViewGroup.java:6400)
        at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1828)
        at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1656)
        at android.widget.LinearLayout.onLayout(LinearLayout.java:1565)
        at android.view.View.layout(View.java:21112)
        at android.view.ViewGroup.layout(ViewGroup.java:6400)
        at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
        at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
        at com.android.internal.policy.DecorView.onLayout(DecorView.java:883)
        at android.view.View.layout(View.java:21112)
        at android.view.ViewGroup.layout(ViewGroup.java:6400)
        at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:3508)
        at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2931)
        at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1931)
        at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:8368)
        at android.view.Choreographer$CallbackRecord.run(Choreographer.java:1088)
        at android.view.Choreographer.doCallbacks(Choreographer.java:900)
        at android.view.Choreographer.doFrame(Choreographer.java:824)
        at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:1074)
        at android.os.Handler.handleCallback(Handler.java:873)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:226)
        at android.app.ActivityThread.main(ActivityThread.java:7210)
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:499)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:961)
     Caused by: java.lang.IllegalArgumentException: The style on this component requires your app theme to be Theme.MaterialComponents (or a descendant).
        at com.google.android.material.internal.ThemeEnforcement.checkTheme(ThemeEnforcement.java:248)
        at com.google.android.material.internal.ThemeEnforcement.checkMaterialTheme(ThemeEnforcement.java:222)
        at com.google.android.material.internal.ThemeEnforcement.checkCompatibleTheme(ThemeEnforcement.java:150)
        at com.google.android.material.internal.ThemeEnforcement.obtainStyledAttributes(ThemeEnforcement.java:81)
        at com.google.android.material.card.MaterialCardView.<init>(MaterialCardView.java:124)
        at com.google.android.material.card.MaterialCardView.<init>(MaterialCardView.java:114)
            ... 61 more

我的xml布局第11行

<com.google.android.material.card.MaterialCardView

使用的 gradle 版本:

implementation 'com.google.android.material:material:1.1.0'

list 应用主题

android:theme="@style/AppTheme.MaterialComponents"

应用主题风格

<style name="NoActionBarHome" parent="Theme.MaterialComponents.Light.DarkActionBar">
        <item name="colorPrimary">@color/colorPrimary</item>
        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
        <item name="colorAccent">@color/colorAccent</item>

    </style>
    <!-- Base application theme. -->
    <style name="AppTheme.MaterialComponents" parent="Theme.MaterialComponents.Light.DarkActionBar">
        <!-- Customize your theme here. -->
        <item name="colorPrimary">@color/colorPrimary</item>
        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
        <item name="colorAccent">@color/colorAccent</item>
        <item name="windowNoTitle">true</item>
        <item name="windowActionBar">false</item>
        <item name="android:windowFullscreen">true</item>
        <item name="android:windowContentOverlay">@null</item>
    </style>

我用来调用布局文件的代码

布局文件名:R.layout.row

 @Override
        public View getView(int position, View convertView,  ViewGroup parent) {
            layoutInflater = (LayoutInflater) getApplicationContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            row = layoutInflater.inflate(R.layout.row, parent, false);
            images = row.findViewById(R.id.image);
            myTitle = row.findViewById(R.id.textView1);
            myDescription = row.findViewById(R.id.textView2);
            // now set our resources on views
            Bitmap bmImg = BitmapFactory.decodeFile(rImgs[position]);
            images.setImageBitmap(bmImg);
            myTitle.setText(rTitle[position]);
            myDescription.setText(rDescription[position]);

            return row;
        }

如果您需要更多信息，请告诉我，谢谢

Answer 1

问题是:

 Caused by: java.lang.IllegalArgumentException: The style on this component requires your app theme to be Theme.MaterialComponents (or a descendant).

适配器中使用的上下文存在问题。您必须传入 Activity，而不是 ApplicationContext。
ApplicationContext 没有应用主题。

在你的代码更改中

 layoutInflater = (LayoutInflater) 
  getApplicationContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);

到

  layoutInflater = (LayoutInflater) 
     context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

其中 context 是 Activity。