java.lang.ClassCastException：在自定义复合组件

Question

我有一个活动，通过调用下面的xml来设置xml。这个xml布局inturn调用一个自定义复合组件，它设置了两个按钮和一个edittext。然后，我的主要活动将从自定义复合组件定义的编辑文本中获取值。我有下面的logcat报告，但看不到它是什么，我不正确。

XML布局文件

 <com.android.control.MinutePicker 
      android:id="@+id/MinPick" 
      android:orientation="vertical" 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content"> 
     </com.android.control.MinutePicker> 

com.android.control.MinutePicker

but1 = new Button(context); 
but1.setTextSize(TEXT_SIZE); 
but1.setText("-"); 
but2 = new Button(context); 
but2.setTextSize(TEXT_SIZE); 
but2.setText("-"); 
valueText = new EditText(context); 
valueText.setTextSize(TEXT_SIZE); 
valueText.setGravity(Gravity.CENTER_VERTICAL | Gravity.CENTER_HORIZONTAL); 
valueText.setText(0); 
this.setLayoutParams(new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT)); 
LayoutParams elementParams = new LinearLayout.LayoutParams(ELEMENT_WIDTH, ELEMENT_HEIGHT); 

    addView(but1, elementParams); 
    addView(valueText, elementParams); 
    addView(but2, elementParams); 

主要的活动，然后改掉得到编辑文本的价值。

   EditText Identifier = (EditText)findViewById(R.id.MinPick); 
      String value = Identifier.getText().toString(); 
      Toast toast = Toast.makeText(PerfectSleepActivity.this, value, Toast.LENGTH_SHORT); 
      toast.setGravity(Gravity.CENTER, 0, 0); 
      toast.show(); 

logcat的报告

05-08 19:03:56.141: E/AndroidRuntime(200): Uncaught handler: thread main exiting due to uncaught exception 
05-08 19:03:57.730: E/AndroidRuntime(200): java.lang.ClassCastException: com.android.control.MinutePicker 
05-08 19:03:57.730: E/AndroidRuntime(200): at com.ap.df.DFActivity$2.onClick(PerfectSleepActivity.java:37) 
05-08 19:03:57.730: E/AndroidRuntime(200): at android.view.View.performClick(View.java:2344) 
05-08 19:03:57.730: E/AndroidRuntime(200): at android.view.View.onTouchEvent(View.java:4133) 
05-08 19:03:57.730: E/AndroidRuntime(200): at android.widget.TextView.onTouchEvent(TextView.java:6510) 
05-08 19:03:57.730: E/AndroidRuntime(200): at android.view.View.dispatchTouchEvent(View.java:3672) 
05-08 19:03:57.730: E/AndroidRuntime(200): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:882) 
05-08 19:03:57.730: E/AndroidRuntime(200): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:882) 
05-08 19:03:57.730: E/AndroidRuntime(200): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:882) 
05-08 19:03:57.730: E/AndroidRuntime(200): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:882) 
05-08 19:03:57.730: E/AndroidRuntime(200): at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:1712) 
05-08 19:03:57.730: E/AndroidRuntime(200): at com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1202) 
05-08 19:03:57.730: E/AndroidRuntime(200): at android.app.Activity.dispatchTouchEvent(Activity.java:1987) 
05-08 19:03:57.730: E/AndroidRuntime(200): at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:1696) 
05-08 19:03:57.730: E/AndroidRuntime(200): at android.view.ViewRoot.handleMessage(ViewRoot.java:1658) 
05-08 19:03:57.730: E/AndroidRuntime(200): at android.os.Handler.dispatchMessage(Handler.java:99) 
05-08 19:03:57.730: E/AndroidRuntime(200): at android.os.Looper.loop(Looper.java:123) 
05-08 19:03:57.730: E/AndroidRuntime(200): at android.app.ActivityThread.main(ActivityThread.java:4203) 
05-08 19:03:57.730: E/AndroidRuntime(200): at java.lang.reflect.Method.invokeNative(Native Method) 
05-08 19:03:57.730: E/AndroidRuntime(200): at java.lang.reflect.Method.invoke(Method.java:521) 
05-08 19:03:57.730: E/AndroidRuntime(200): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791) 
05-08 19:03:57.730: E/AndroidRuntime(200): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549) 
05-08 19:03:57.730: E/AndroidRuntime(200): at dalvik.system.NativeStart.main(Native Method) 

Answer 1

它看起来像你想投类类型MinutePicker（com.android.control.MinutePicker）来EditText上的这行代码：

EditText Identifier = (EditText)findViewById(R.id.MinPick); 

R.id.MinPick属于MinutePicker类型，不是EditText。

这不起作用。 MinutePicker是否从EditText继承？请发布类标识符（不仅包含在其中的代码）。

也许你的意思是做到以下几点：

MinutePicker mp = (MinutePicker)findViewById(R.id.MinPick);