android.graphics.drawable.ColorDrawable不能转换为android.support.v7.widget.RoundRectDrawableWithShadow

我试图在我的应用程序中使用CardView，在我的xml布局中工作得很好。 因为我想在我的代码中生成它们，而不是通过XML我试图设置半径CardView.setRadius（） – Android开发人员build议的方法（ https://developer.android.com/preview/material/ui-widgets .html＃cardview ）。

这根本不起作用！ 我希望有人可以帮助我，我的问题或与XML布局有一个很好的解决方法。

这是我的代码：

int height = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 100, getResources().getDisplayMetrics()); float radius = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 4, getResources().getDisplayMetrics()); for (String color : colors) { CardView card = new CardView(getActivity()); TextView text = new TextView(getActivity()); card.setBackgroundColor(Color.parseColor("#"+color)); card.setLayoutParams(new ViewGroup.LayoutParams( ViewGroup.LayoutParams.MATCH_PARENT, height)); card.setRadius(radius); //Error!! text.setText(args.get(colors.indexOf(color)) + " - #" + color); card.addView(text); group.addView(card); } 

这是我的日志：

 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.brobox.materialcolorpalette/com.brobox.materialcolorpalette.MainActivity}: java.lang.ClassCastException: android.graphics.drawable.ColorDrawable cannot be cast to android.support.v7.widget.RoundRectDrawableWithShadow at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2212) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2271) at android.app.ActivityThread.access$800(ActivityThread.java:144) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1205) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:136) at android.app.ActivityThread.main(ActivityThread.java:5146) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:515) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:796) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:612) at dalvik.system.NativeStart.main(Native Method) Caused by: java.lang.ClassCastException: android.graphics.drawable.ColorDrawable cannot be cast to android.support.v7.widget.RoundRectDrawableWithShadow at android.support.v7.widget.CardViewEclairMr1.setRadius(CardViewEclairMr1.java:76) at android.support.v7.widget.CardView.setRadius(CardView.java:89) at com.brobox.materialcolorpalette.ColorFragment.onCreateView(ColorFragment.java:61) at android.support.v4.app.Fragment.performCreateView(Fragment.java:1504) at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:942) at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1121) at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682) at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1484) at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:571) at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1171) at android.app.Activity.performStart(Activity.java:5241) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2178)            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2271)            at android.app.ActivityThread.access$800(ActivityThread.java:144)            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1205)            at android.os.Handler.dispatchMessage(Handler.java:102)            at android.os.Looper.loop(Looper.java:136)            at android.app.ActivityThread.main(ActivityThread.java:5146)            at java.lang.reflect.Method.invokeNative(Native Method)            at java.lang.reflect.Method.invoke(Method.java:515)            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:796)            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:612)            at dalvik.system.NativeStart.main(Native Method) 

更新：我现在使用新的Lollipop SDK与Appcompat版本21.现在它甚至不工作，当我尝试没有setRadius（）。

新日志：

 java.lang.ClassCastException: android.graphics.drawable.ColorDrawable cannot be cast to android.support.v7.widget.RoundRectDrawableWithShadow at android.support.v7.widget.CardViewEclairMr1.getShadowBackground(CardViewEclairMr1.java:148) at android.support.v7.widget.CardViewEclairMr1.getMinWidth(CardViewEclairMr1.java:139) at android.support.v7.widget.CardView.onMeasure(CardView.java:181) at android.view.View.measure(View.java:16521) at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125) at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1404) at android.widget.LinearLayout.measureVertical(LinearLayout.java:695) at android.widget.LinearLayout.onMeasure(LinearLayout.java:588) at android.view.View.measure(View.java:16521) at android.widget.ScrollView.measureChildWithMargins(ScrollView.java:1226) at android.widget.FrameLayout.onMeasure(FrameLayout.java:310) at android.widget.ScrollView.onMeasure(ScrollView.java:326) at android.view.View.measure(View.java:16521) at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125) at android.widget.FrameLayout.onMeasure(FrameLayout.java:310) at android.view.View.measure(View.java:16521) at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125) at android.widget.FrameLayout.onMeasure(FrameLayout.java:310) at android.view.View.measure(View.java:16521) at android.support.v4.widget.DrawerLayout.onMeasure(DrawerLayout.java:848) at android.view.View.measure(View.java:16521) at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125) at android.widget.FrameLayout.onMeasure(FrameLayout.java:310) at android.view.View.measure(View.java:16521) at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125) at android.support.v7.internal.widget.ActionBarOverlayLayout.onMeasure(ActionBarOverlayLayout.java:453) at android.view.View.measure(View.java:16521) at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125) at android.widget.FrameLayout.onMeasure(FrameLayout.java:310) at android.view.View.measure(View.java:16521) at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125) at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1404) at android.widget.LinearLayout.measureVertical(LinearLayout.java:695) at android.widget.LinearLayout.onMeasure(LinearLayout.java:588) at android.view.View.measure(View.java:16521) at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125) at android.widget.FrameLayout.onMeasure(FrameLayout.java:310) at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2552) at android.view.View.measure(View.java:16521) at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:1915) at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1109) at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1291) at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:996) at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5603) at android.view.Choreographer$CallbackRecord.run(Choreographer.java:761) at android.view.Choreographer.doCallbacks(Choreographer.java:574) at android.view.Choreographer.doFrame(Choreographer.java:544) at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:747) at android.os.Handler.handleCallback(Handler.java:733) at android.os.Handler.dispatchMessage(Handler.java:95) at android.os.Looper.loop(Looper.java:136) at android.app.ActivityThread.main(ActivityThread.java:5146) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:515) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:796) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:612) at dalvik.system.NativeStart.main(Native Method) 

更新2：我想这是谷歌的一个错误。 所以我为他们指出： https : //code.google.com/p/android/issues/detail?id=77843

Answer 1

调用在View类中定义的setBackgroundColor（）方法时出现此错误。

 cardView.setBackgroundColor(Color.parseColor("#ffffcc")); 

而是应该调用Card BackgroundColor（）方法，该方法是CardView特定的并在CardView类中定义的。

此代码设置背景颜色和angular半径适用于我：

 cardView.setCardBackgroundColor(Color.parseColor("#ffffcc")); cardView.setRadius(50); 

Answer 2

我发现你不能设置卡片视图的背景。 即使在XML中。 所以这是我的解决方法：

把所有的东西放在卡的子布局中：

 <android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android" android:layout_height="match_parent" android:layout_width="match_parent" android:elevation="10dp"> <RelativeLayout android:layout_width="fill_parent" android:layout_height="fill_parent" android:id="@+id/holder_relative_layout" android:orientation="horizontal" android:gravity="center_vertical"> ... 

然后在代码中：

 cardView.row.findViewById(R.id.holder_relative_layout).setBackgroundColor(getResources().getColor(R.color.MediumSeaGreen)); 

Answer 3

我知道这是一个老问题，但是，如果你想改变一个bgcolor CardView现在在android.support.v7.widget.CardView你可以使用setCardBackgroundColor ：

  cardView.setCardBackgroundColor(Color.parseColor("#dddddd")); 

要不就

  cv.setCardBackgroundColor(Color.LTGRAY); 

Answer 4

有关SetCardBAckgroundColor使用SetCardBAckgroundColor的评论是正确的，但我不得不将视图投到View以及编译

 ((CardView)holder.itemView).setCardBackgroundColor(Color.parseColor("#FFFFCC")); 

现在所有的作品。

Answer 5

我面临同样的崩溃。 问题是你在代码中以编程方式设置CardView的背景颜色。

 card.setBackgroundColor(Color.parseColor("#"+color)); 

注释行。 并在xml中设置背景和其他属性。 不要以编程方式进行。

这对我有效。 🙂

最好为不同的情况/数据定义不同的xml文件，以便区分。

Answer 6

如果您先设置后台可绘制，然后再设置颜色，这是一个支持库的简单问题。 他们（谷歌）调用getDrawable（）来设置背景颜色，如果你调用颜色更改。 他们把Drawable转换成RoundRectdrawable，你可能有另外一种Drawable。 例如一个ninepatch Drawable。 只需重写setBackgroundColor（）setBackgroundDrawable（new RoundedDrawable（…））不知道构造函数和类的名称，只看Cardview的源代码。

这就是问题：

 @Override public void setBackgroundColor(CardViewDelegate cardView, int color) { ((RoundRectDrawable) (cardView.getBackground())).setColor(color); } 

改成：

 @Override public void setBackgroundColor(int color) { setBackgroundDrawable(new RoundRectDrawable(color, getRadius())); }