android - java.lang.ClassCastException : android. view.ViewGroup$LayoutParams 没有使用 LayoutParams

Question

我使用一个具有RelativeLayout -> ScrollView -> LinearLayout 的 View 。我得到了异常(exception):

11-22 11:17:24.605: ERROR/AndroidRuntime(5161): FATAL EXCEPTION: main
11-22 11:17:24.605: ERROR/AndroidRuntime(5161): java.lang.ClassCastException: android.view.ViewGroup$LayoutParams
11-22 11:17:24.605: ERROR/AndroidRuntime(5161):     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3131)
11-22 11:17:24.605: ERROR/AndroidRuntime(5161):     at android.widget.FrameLayout.onMeasure(FrameLayout.java:245)
11-22 11:17:24.605: ERROR/AndroidRuntime(5161):     at android.view.View.measure(View.java:8172)
11-22 11:17:24.605: ERROR/AndroidRuntime(5161):     at android.view.ViewRoot.performTraversals(ViewRoot.java:805)
11-22 11:17:24.605: ERROR/AndroidRuntime(5161):     at android.view.ViewRoot.handleMessage(ViewRoot.java:1744)
11-22 11:17:24.605: ERROR/AndroidRuntime(5161):     at android.os.Handler.dispatchMessage(Handler.java:99)
11-22 11:17:24.605: ERROR/AndroidRuntime(5161):     at android.os.Looper.loop(Looper.java:144)
11-22 11:17:24.605: ERROR/AndroidRuntime(5161):     at android.app.ActivityThread.main(ActivityThread.java:4937)
11-22 11:17:24.605: ERROR/AndroidRuntime(5161):     at java.lang.reflect.Method.invokeNative(Native Method)
11-22 11:17:24.605: ERROR/AndroidRuntime(5161):     at java.lang.reflect.Method.invoke(Method.java:521)
11-22 11:17:24.605: ERROR/AndroidRuntime(5161):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
11-22 11:17:24.605: ERROR/AndroidRuntime(5161):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
11-22 11:17:24.605: ERROR/AndroidRuntime(5161):     at dalvik.system.NativeStart.main(Native Method)

为什么它只是偶尔发生？为什么没有代码失败的细节？

更新:我怀疑它应该围绕此代码失败:

EditText input = new EditText(context);
input.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));

LayoutParams 是 RelativeLayout.LayoutParams

Answer 1

使用 new LinearLayout.LayoutParams(...) 而不是 new LayoutParams(...)

LayoutParams 总是需要使用父布局的类。例如。如果 EditText 在 FrameLayout 内，则必须使用 FrameLayout.LayoutParams。