android - 膨胀内部类 View 时出错

Question

我正在尝试膨胀内部类 View 并遇到“错误膨胀类”问题。我引用了 this post这很有帮助，但我仍然不知道为什么我不能让它工作。

这是代码摘录、我的 XML 和 logcat。

编辑:我还注意到，当我清楚地知道“CupcakeMessageView(Context, AttributeSet)”时​​，logcat 声明“没有这样的方法异常”。

谢谢大家!

public class CupcakeMessage extends Activity {

    class CupcakeMessageView extends View {
        private static final int TEXT_SIZE = 12;
        private static final int X_OFFSET = 15;

        private Paint mPaint;   

        public CupcakeMessageView(Context context) {
            super(context);
        }

        public CupcakeMessageView(Context context, AttributeSet attrs) {
            super(context, attrs);
            mContext = context;
            ...
        }

        more class stuff... 
    }

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);        
        setContentView(R.layout.cupcake_message); 

        ...      
    }
}

这是 XML

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" >

    <view class="com.cmllc.zcc.CupcakeMessage$CupcakeMessageView"
        android:id="@+id/cupcake_message_view"
        android:screenOrientation="portrait"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />
    more views...

日志:

12-19 09:31:24.249: ERROR/AndroidRuntime(5435): FATAL EXCEPTION: main
12-19 09:31:24.249: ERROR/AndroidRuntime(5435): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.cmllc.zcc/com.cmllc.zcc.CupcakeMessage}: android.view.InflateException: Binary XML file line #7: Error inflating class com.cmllc.zcc.CupcakeMessage$CupcakeMessageView
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at android.app.ActivityThread.access$2300(ActivityThread.java:125)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at android.os.Handler.dispatchMessage(Handler.java:99)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at android.os.Looper.loop(Looper.java:123)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at android.app.ActivityThread.main(ActivityThread.java:4627)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at java.lang.reflect.Method.invokeNative(Native Method)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at java.lang.reflect.Method.invoke(Method.java:521)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at dalvik.system.NativeStart.main(Native Method)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435): Caused by: android.view.InflateException: Binary XML file line #7: Error inflating class com.cmllc.zcc.CupcakeMessage$CupcakeMessageView
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at android.view.LayoutInflater.createView(LayoutInflater.java:503)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:565)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at android.view.LayoutInflater.rInflate(LayoutInflater.java:618)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at android.view.LayoutInflater.inflate(LayoutInflater.java:407)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at android.view.LayoutInflater.inflate(LayoutInflater.java:320)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at android.view.LayoutInflater.inflate(LayoutInflater.java:276)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:198)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at android.app.Activity.setContentView(Activity.java:1647)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at com.cmllc.zcc.CupcakeMessage.onCreate(CupcakeMessage.java:119)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     ... 11 more
12-19 09:31:24.249: ERROR/AndroidRuntime(5435): Caused by: java.lang.NoSuchMethodException: CupcakeMessageView(Context,AttributeSet)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at java.lang.Class.getMatchingConstructor(Class.java:660)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at java.lang.Class.getConstructor(Class.java:477)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     at android.view.LayoutInflater.createView(LayoutInflater.java:475)
12-19 09:31:24.249: ERROR/AndroidRuntime(5435):     ... 21 more

Answer 1

你需要在内部类中添加public static。

• public 因为它需要从外部可见。
• static 因为如果不是，您将需要 CupcakeMessage 来实例化它。

我还是建议在单独的类中执行 View。