MaterialCardView 因 material:1.1.0 崩溃
MaterialCardView crashes with material:1.1.0
我正在使用 MaterialCardView 作为我的 cardview 布局。现在，Android-studio 开始向我展示我应该更新到 1.1.0
而不是当前的 implementation "com.google.android.material:material:1.0.0"
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/edit_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:orientation="vertical"
android:layout_margin="@dimen/activity_vertical_margin">
<com.google.android.material.card.MaterialCardView
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:cardCornerRadius="8dp"
app:cardElevation="8dp">
<...more layout>
</com.google.android.material.card.MaterialCardView>
</LinearLayout>
使用 1.1.0，我遇到崩溃 Error inflating class com.google.android.material.card.MaterialCardView
所以，我有 3 个案例：
- 坚持
1.0.0并使用MaterialCardView（有效，但不是首选）
- 更新到
1.1.0（或 1.2.0-alpha）并使用 androidx.CardView（有效，但不是首选）
- 更新到
1.1.0 并更改 MaterialCardView（首选，但不工作）
由于我想选择选项 #3，但我没有任何解决方案，有人可以提供线索吗？
更新
我的风格（我也有 style 和 style-night。这里我只发布 style）：
<resources>
<!-- Base application theme. -->
<style name="AppTheme" parent="Theme.AppCompat.DayNight">
<!-- Customize your theme here. -->
<item name="colorPrimary">@color/colorPrimary</item>
<item name="colorPrimaryDark">@color/colorPrimaryDark</item>
<item name="colorAccent">@color/colorAccent</item>
</style>
<style name="AppTheme.NoActionBar">
<item name="windowActionBar">false</item>
<item name="windowNoTitle">true</item>
</style>
<style name="AppTheme.AppBarOverlay" parent="ThemeOverlay.AppCompat.Dark.ActionBar" />
<style name="ThemeOverlay.AppCompat.navTheme">
<!-- Color of text and icon when SELECTED -->
<item name="colorPrimary">#ffffff</item>
<!-- Background color when SELECTED -->
<item name="colorControlHighlight">@color/colorPrimary</item>
</style>
</resources>
这是错误（来自Logcat）
2020-02-12 13:34:18.171 12562-12562/com.example.phocast E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.phocast, PID: 12562
android.view.InflateException: Binary XML file line #10 in com.example.phocast:layout/fragment_place: Binary XML file line #10 in com.example.phocast:layout/fragment_place: Error inflating class com.google.android.material.card.MaterialCardView
Caused by: android.view.InflateException: Binary XML file line #10 in com.example.phocast:layout/fragment_place: Error inflating class com.google.android.material.card.MaterialCardView
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:854)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:1006)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:961)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:1123)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:1084)
at android.view.LayoutInflater.inflate(LayoutInflater.java:682)
at android.view.LayoutInflater.inflate(LayoutInflater.java:534)
at android.view.LayoutInflater.inflate(LayoutInflater.java:481)
at com.example.phocast.MainActivity.onOptionsItemSelected(MainActivity.java:555)
at android.app.Activity.onMenuItemSelected(Activity.java:4137)
at androidx.fragment.app.FragmentActivity.onMenuItemSelected(FragmentActivity.java:383)
at androidx.appcompat.app.AppCompatActivity.onMenuItemSelected(AppCompatActivity.java:219)
at androidx.appcompat.view.WindowCallbackWrapper.onMenuItemSelected(WindowCallbackWrapper.java:109)
at androidx.appcompat.view.WindowCallbackWrapper.onMenuItemSelected(WindowCallbackWrapper.java:109)
at androidx.appcompat.app.ToolbarActionBar.onMenuItemClick(ToolbarActionBar.java:64)
at androidx.appcompat.widget.Toolbar.onMenuItemClick(Toolbar.java:207)
at androidx.appcompat.widget.ActionMenuView$MenuBuilderCallback.onMenuItemSelected(ActionMenuView.java:781)
at androidx.appcompat.view.menu.MenuBuilder.dispatchMenuItemSelected(MenuBuilder.java:840)
at androidx.appcompat.view.menu.MenuItemImpl.invoke(MenuItemImpl.java:158)
at androidx.appcompat.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:991)
at androidx.appcompat.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:981)
at androidx.appcompat.widget.ActionMenuView.invokeItem(ActionMenuView.java:625)
at androidx.appcompat.view.menu.ActionMenuItemView.onClick(ActionMenuItemView.java:151)
at android.view.View.performClick(View.java:7125)
at android.view.View.performClickInternal(View.java:7102)
at android.view.View.access00(View.java:801)
at android.view.View$PerformClick.run(View.java:27336)
at android.os.Handler.handleCallback(Handler.java:883)
at android.os.Handler.dispatchMessage(Handler.java:100)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:7356)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)
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)
at java.lang.reflect.Constructor.newInstance0(Native Method)
at java.lang.reflect.Constructor.newInstance(Constructor.java:343)
at android.view.LayoutInflater.createView(LayoutInflater.java:854)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:1006)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:961)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:1123)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:1084)
at android.view.LayoutInflater.inflate(LayoutInflater.java:682)
at android.view.LayoutInflater.inflate(LayoutInflater.java:534)
at android.view.LayoutInflater.inflate(LayoutInflater.java:481)
at com.example.phocast.MainActivity.onOptionsItemSelected(MainActivity.java:555)
at android.app.Activity.onMenuItemSelected(Activity.java:4137)
at androidx.fragment.app.FragmentActivity.onMenuItemSelected(FragmentActivity.java:383)
at androidx.appcompat.app.AppCompatActivity.onMenuItemSelected(AppCompatActivity.java:219)
at androidx.appcompat.view.WindowCallbackWrapper.onMenuItemSelected(WindowCallbackWrapper.java:109)
at androidx.appcompat.view.WindowCallbackWrapper.onMenuItemSelected(WindowCallbackWrapper.java:109)
at androidx.appcompat.app.ToolbarActionBar.onMenuItemClick(ToolbarActionBar.java:64)
at androidx.appcompat.widget.Toolbar.onMenuItemClick(Toolbar.java:207)
at androidx.appcompat.widget.ActionMenuView$MenuBuilderCallback.onMenuItemSelected(ActionMenuView.java:781)
at androidx.appcompat.view.menu.MenuBuilder.dispatchMenuItemSelected(MenuBuilder.java:840)
at androidx.appcompat.view.menu.MenuItemImpl.invoke(MenuItemImpl.java:158)
at androidx.appcompat.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:991)
at androidx.appcompat.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:981)
at androidx.appcompat.widget.ActionMenuView.invokeItem(ActionMenuView.java:625)
at androidx.appcompat.view.menu.ActionMenuItemView.onClick(ActionMenuItemView.java:151)
at android.view.View.performClick(View.java:7125)
at android.view.View.performClickInternal(View.java:7102)
at android.view.View.access00(View.java:801)
at android.view.View$PerformClick.run(View.java:27336)
at android.os.Handler.handleCallback(Handler.java:883)
at android.os.Handler.dispatchMessage(Handler.java:100)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:7356)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)
2020-02-12 13:34:18.620 12562-12584/com.example.phocast I/example.phocas: Background young concurrent copying GC freed 110384(4259KB) AllocSpace objects, 46(1212KB) LOS objects, 41% free, 7792KB/12MB, paused 1.092ms total 150.548ms
2020-02-12 13:34:18.692 12562-12562/com.example.phocast I/Process: Sending signal. PID: 12562 SIG: 9
试用最新版本
implementation 'com.google.android.material:material:1.2.0-alpha03'
style.xml:
<style name="AppTheme" 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>
</style>
在你的 xml:
<com.google.android.material.card.MaterialCardView
android:layout_width="match_parent"
android:layout_height="wrap_content">
</com.google.android.material.card.MaterialCardView>
错误在堆栈跟踪中：
Caused by: java.lang.IllegalArgumentException: The style on this component requires your app theme to be Theme.MaterialComponents (or a descendant).
对于 1.1.0 版本，您必须继承 Theme.MaterialComponents。
将您的应用主题更改为
<style name="AppTheme" parent="Theme.MaterialComponents.DayNight">
<!-- .... -->
</style>
您也可以将其保存在您的 materialcardview 中：
<com.google.android.material.card.MaterialCardView
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:cardCornerRadius="8dp"
**** android:theme="@style/Theme.MaterialComponents.Light" *****
app:cardElevation="8dp">
您需要更改 AppTheme 以使其父主题成为 MaterialComponent
的后代
在您的特定情况下，将 AppTheme 从
更改为
<style name="AppTheme" parent="Theme.AppCompat.DayNight">
到
<style name="AppTheme" parent="Theme.MaterialComponents.DayNight">
应该可以解决这个问题。
如果在 styles.xml 中将主题更改为 Theme.MaterialComponents 后没有效果，请确保您已添加 样式 标签在 MaterialCard.
style="@style/Widget.MaterialComponents.CardView"
将此 <style name="AppTheme" parent="Theme.AppCompat.DayNight> 更改为 <style name="AppTheme" parent="Theme.MaterialComponents.DayNight">
后有效
在我的例子中，我只是添加了 android:theme="" 属性并且它起作用了。我的 Material Card View 元素如下 -
<com.google.android.material.card.MaterialCardView
android:id="@+id/edit_profile_card"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginStart="@dimen/dp_16"
android:layout_marginTop="@dimen/dp_10"
android:layout_marginEnd="@dimen/dp_16"
android:layout_marginBottom="@dimen/dp_10"
**android:theme="@style/Theme.MaterialComponents.DayNight"**
app:cardCornerRadius="@dimen/dp_10"
app:cardElevation="@dimen/dp_20"
app:state_dragged="false">
....
....
</com.google.android.material.card.MaterialCardView>
只需将 style.xml 中的主题更改为：
<style name="AppTheme" parent="Theme.MaterialComponents.DayNight">
它会起作用
如果您想保留应用程序 (AppCompat) 之前的主题，您可以使用 Bridge 主题。
他们被描述为 here
来自文档：
Bridge themes inherit from AppCompat themes, but also define the new Material Components theme attributes for you. If you use a bridge theme, you can start using Material Design components without changing your app theme.
例如 res/values/themes.xml:
<style name="AppTheme" parent="Theme.MaterialComponents.Light.Bridge">
<item name="colorPrimary">@color/primary</item>
<item name="colorPrimaryDark">@color/primary_dark</item>
<item name="colorAccent">@color/accent</item>
</style>
我正在使用 MaterialCardView 作为我的 cardview 布局。现在，Android-studio 开始向我展示我应该更新到 1.1.0
implementation "com.google.android.material:material:1.0.0"
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/edit_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:orientation="vertical"
android:layout_margin="@dimen/activity_vertical_margin">
<com.google.android.material.card.MaterialCardView
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:cardCornerRadius="8dp"
app:cardElevation="8dp">
<...more layout>
</com.google.android.material.card.MaterialCardView>
</LinearLayout>
使用 1.1.0，我遇到崩溃 Error inflating class com.google.android.material.card.MaterialCardView
所以，我有 3 个案例：
- 坚持
1.0.0并使用MaterialCardView（有效，但不是首选） - 更新到
1.1.0（或 1.2.0-alpha）并使用androidx.CardView（有效，但不是首选） - 更新到
1.1.0并更改MaterialCardView（首选，但不工作）
由于我想选择选项 #3，但我没有任何解决方案，有人可以提供线索吗？
更新
我的风格（我也有 style 和 style-night。这里我只发布 style）：
<resources>
<!-- Base application theme. -->
<style name="AppTheme" parent="Theme.AppCompat.DayNight">
<!-- Customize your theme here. -->
<item name="colorPrimary">@color/colorPrimary</item>
<item name="colorPrimaryDark">@color/colorPrimaryDark</item>
<item name="colorAccent">@color/colorAccent</item>
</style>
<style name="AppTheme.NoActionBar">
<item name="windowActionBar">false</item>
<item name="windowNoTitle">true</item>
</style>
<style name="AppTheme.AppBarOverlay" parent="ThemeOverlay.AppCompat.Dark.ActionBar" />
<style name="ThemeOverlay.AppCompat.navTheme">
<!-- Color of text and icon when SELECTED -->
<item name="colorPrimary">#ffffff</item>
<!-- Background color when SELECTED -->
<item name="colorControlHighlight">@color/colorPrimary</item>
</style>
</resources>
这是错误（来自Logcat）
2020-02-12 13:34:18.171 12562-12562/com.example.phocast E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.phocast, PID: 12562
android.view.InflateException: Binary XML file line #10 in com.example.phocast:layout/fragment_place: Binary XML file line #10 in com.example.phocast:layout/fragment_place: Error inflating class com.google.android.material.card.MaterialCardView
Caused by: android.view.InflateException: Binary XML file line #10 in com.example.phocast:layout/fragment_place: Error inflating class com.google.android.material.card.MaterialCardView
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:854)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:1006)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:961)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:1123)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:1084)
at android.view.LayoutInflater.inflate(LayoutInflater.java:682)
at android.view.LayoutInflater.inflate(LayoutInflater.java:534)
at android.view.LayoutInflater.inflate(LayoutInflater.java:481)
at com.example.phocast.MainActivity.onOptionsItemSelected(MainActivity.java:555)
at android.app.Activity.onMenuItemSelected(Activity.java:4137)
at androidx.fragment.app.FragmentActivity.onMenuItemSelected(FragmentActivity.java:383)
at androidx.appcompat.app.AppCompatActivity.onMenuItemSelected(AppCompatActivity.java:219)
at androidx.appcompat.view.WindowCallbackWrapper.onMenuItemSelected(WindowCallbackWrapper.java:109)
at androidx.appcompat.view.WindowCallbackWrapper.onMenuItemSelected(WindowCallbackWrapper.java:109)
at androidx.appcompat.app.ToolbarActionBar.onMenuItemClick(ToolbarActionBar.java:64)
at androidx.appcompat.widget.Toolbar.onMenuItemClick(Toolbar.java:207)
at androidx.appcompat.widget.ActionMenuView$MenuBuilderCallback.onMenuItemSelected(ActionMenuView.java:781)
at androidx.appcompat.view.menu.MenuBuilder.dispatchMenuItemSelected(MenuBuilder.java:840)
at androidx.appcompat.view.menu.MenuItemImpl.invoke(MenuItemImpl.java:158)
at androidx.appcompat.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:991)
at androidx.appcompat.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:981)
at androidx.appcompat.widget.ActionMenuView.invokeItem(ActionMenuView.java:625)
at androidx.appcompat.view.menu.ActionMenuItemView.onClick(ActionMenuItemView.java:151)
at android.view.View.performClick(View.java:7125)
at android.view.View.performClickInternal(View.java:7102)
at android.view.View.access00(View.java:801)
at android.view.View$PerformClick.run(View.java:27336)
at android.os.Handler.handleCallback(Handler.java:883)
at android.os.Handler.dispatchMessage(Handler.java:100)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:7356)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)
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)
at java.lang.reflect.Constructor.newInstance0(Native Method)
at java.lang.reflect.Constructor.newInstance(Constructor.java:343)
at android.view.LayoutInflater.createView(LayoutInflater.java:854)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:1006)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:961)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:1123)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:1084)
at android.view.LayoutInflater.inflate(LayoutInflater.java:682)
at android.view.LayoutInflater.inflate(LayoutInflater.java:534)
at android.view.LayoutInflater.inflate(LayoutInflater.java:481)
at com.example.phocast.MainActivity.onOptionsItemSelected(MainActivity.java:555)
at android.app.Activity.onMenuItemSelected(Activity.java:4137)
at androidx.fragment.app.FragmentActivity.onMenuItemSelected(FragmentActivity.java:383)
at androidx.appcompat.app.AppCompatActivity.onMenuItemSelected(AppCompatActivity.java:219)
at androidx.appcompat.view.WindowCallbackWrapper.onMenuItemSelected(WindowCallbackWrapper.java:109)
at androidx.appcompat.view.WindowCallbackWrapper.onMenuItemSelected(WindowCallbackWrapper.java:109)
at androidx.appcompat.app.ToolbarActionBar.onMenuItemClick(ToolbarActionBar.java:64)
at androidx.appcompat.widget.Toolbar.onMenuItemClick(Toolbar.java:207)
at androidx.appcompat.widget.ActionMenuView$MenuBuilderCallback.onMenuItemSelected(ActionMenuView.java:781)
at androidx.appcompat.view.menu.MenuBuilder.dispatchMenuItemSelected(MenuBuilder.java:840)
at androidx.appcompat.view.menu.MenuItemImpl.invoke(MenuItemImpl.java:158)
at androidx.appcompat.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:991)
at androidx.appcompat.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:981)
at androidx.appcompat.widget.ActionMenuView.invokeItem(ActionMenuView.java:625)
at androidx.appcompat.view.menu.ActionMenuItemView.onClick(ActionMenuItemView.java:151)
at android.view.View.performClick(View.java:7125)
at android.view.View.performClickInternal(View.java:7102)
at android.view.View.access00(View.java:801)
at android.view.View$PerformClick.run(View.java:27336)
at android.os.Handler.handleCallback(Handler.java:883)
at android.os.Handler.dispatchMessage(Handler.java:100)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:7356)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)
2020-02-12 13:34:18.620 12562-12584/com.example.phocast I/example.phocas: Background young concurrent copying GC freed 110384(4259KB) AllocSpace objects, 46(1212KB) LOS objects, 41% free, 7792KB/12MB, paused 1.092ms total 150.548ms
2020-02-12 13:34:18.692 12562-12562/com.example.phocast I/Process: Sending signal. PID: 12562 SIG: 9
试用最新版本
implementation 'com.google.android.material:material:1.2.0-alpha03'
style.xml:
<style name="AppTheme" 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>
</style>
在你的 xml:
<com.google.android.material.card.MaterialCardView
android:layout_width="match_parent"
android:layout_height="wrap_content">
</com.google.android.material.card.MaterialCardView>
错误在堆栈跟踪中：
Caused by: java.lang.IllegalArgumentException: The style on this component requires your app theme to be Theme.MaterialComponents (or a descendant).
对于 1.1.0 版本，您必须继承 Theme.MaterialComponents。
将您的应用主题更改为
<style name="AppTheme" parent="Theme.MaterialComponents.DayNight">
<!-- .... -->
</style>
您也可以将其保存在您的 materialcardview 中：
<com.google.android.material.card.MaterialCardView
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:cardCornerRadius="8dp"
**** android:theme="@style/Theme.MaterialComponents.Light" *****
app:cardElevation="8dp">
您需要更改 AppTheme 以使其父主题成为 MaterialComponent
的后代在您的特定情况下，将 AppTheme 从
更改为 <style name="AppTheme" parent="Theme.AppCompat.DayNight">
到
<style name="AppTheme" parent="Theme.MaterialComponents.DayNight">
应该可以解决这个问题。
如果在 styles.xml 中将主题更改为 Theme.MaterialComponents 后没有效果，请确保您已添加 样式 标签在 MaterialCard.
style="@style/Widget.MaterialComponents.CardView"
将此 <style name="AppTheme" parent="Theme.AppCompat.DayNight> 更改为 <style name="AppTheme" parent="Theme.MaterialComponents.DayNight">
在我的例子中，我只是添加了 android:theme="" 属性并且它起作用了。我的 Material Card View 元素如下 -
<com.google.android.material.card.MaterialCardView
android:id="@+id/edit_profile_card"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginStart="@dimen/dp_16"
android:layout_marginTop="@dimen/dp_10"
android:layout_marginEnd="@dimen/dp_16"
android:layout_marginBottom="@dimen/dp_10"
**android:theme="@style/Theme.MaterialComponents.DayNight"**
app:cardCornerRadius="@dimen/dp_10"
app:cardElevation="@dimen/dp_20"
app:state_dragged="false">
....
....
</com.google.android.material.card.MaterialCardView>
只需将 style.xml 中的主题更改为：
<style name="AppTheme" parent="Theme.MaterialComponents.DayNight">
它会起作用
如果您想保留应用程序 (AppCompat) 之前的主题，您可以使用 Bridge 主题。 他们被描述为 here
来自文档：
Bridge themes inherit from AppCompat themes, but also define the new Material Components theme attributes for you. If you use a bridge theme, you can start using Material Design components without changing your app theme.
例如 res/values/themes.xml:
<style name="AppTheme" parent="Theme.MaterialComponents.Light.Bridge">
<item name="colorPrimary">@color/primary</item>
<item name="colorPrimaryDark">@color/primary_dark</item>
<item name="colorAccent">@color/accent</item>
</style>