Android I/O 2014演示應用程序問題

Question

我正在嘗試編寫獲取Google L預覽版給我們提供的新共享元素動畫API的句柄。

我一直在嘗試使用代碼庫作爲一個參考點沿：https://developer.android.com/preview/material/animations.html

對我的生活中，我似乎無法讓我的應用程序工作。但是，當我從谷歌運行演示應用程序的過渡工作得很好。

MyActivity.java：

public class MyActivity extends Activity { 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_my); 

     final ImageView imageView = (ImageView)this.findViewById(R.id.img_main); 
    } 


    @Override 
    public boolean onCreateOptionsMenu(Menu menu) { 
     // Inflate the menu; this adds items to the action bar if it is present. 
     getMenuInflater().inflate(R.menu.my, menu); 
     return true; 
    } 

    @Override 
    public boolean onOptionsItemSelected(MenuItem item) { 
     // Handle action bar item clicks here. The action bar will 
     // automatically handle clicks on the Home/Up button, so long 
     // as you specify a parent activity in AndroidManifest.xml. 
     int id = item.getItemId(); 
     if (id == R.id.action_settings) { 
      return true; 
     } 
     return super.onOptionsItemSelected(item); 
    } 

    public void showPhoto(View view) { 
     Intent intent = new Intent(); 
     intent.setClass(this, MyActivity2.class); 

     ImageView hero = (ImageView) ((View) view.getParent()).findViewById(R.id.img_main); 
     ((ViewGroup) hero.getParent()).setTransitionGroup(false); 

     ActivityOptions options = 
       ActivityOptions.makeSceneTransitionAnimation(this, hero, "robot"); 
     startActivity(intent, options.toBundle()); 
    } 
} 

activity_my.xml：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:tools="http://schemas.android.com/tools" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:paddingLeft="@dimen/activity_horizontal_margin" 
    android:paddingRight="@dimen/activity_horizontal_margin" 
    android:paddingTop="@dimen/activity_vertical_margin" 
    android:paddingBottom="@dimen/activity_vertical_margin" 
    tools:context=".MyActivity"> 

    <ImageView 
     android:id="@+id/img_main" 
     android:viewName="photo1" 
     android:layout_width="64dp" 
     android:layout_height="64dp" 
     android:src="@drawable/test" 
     android:onClick="showPhoto"/> 

</RelativeLayout> 

styles.xml：

<resources> 

    <!-- Base application theme. --> 
    <style name="AppTheme" parent="android:Theme.Holo.Light.DarkActionBar"> 
     <item name="android:windowContentTransitions">true</item> 
     <item name="android:windowAllowEnterTransitionOverlap">true</item> 
     <item name="android:windowAllowExitTransitionOverlap">true</item> 
     <item name="android:windowActionBarOverlay">false</item> 
     <item name="android:windowContentOverlay">@null</item> 
    </style> 

</resources> 

的manifest.xml

<?xml version="1.0" encoding="utf-8"?> 
<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
    package="com.example.jms_m_000.transitionshit" > 

    <application 
     android:allowBackup="true" 
     android:icon="@drawable/ic_launcher" 
     android:label="@string/app_name" 
     android:theme="@style/AppTheme" > 
     <activity 
      android:name=".MyActivity" 
      android:label="@string/app_name" > 
      <intent-filter> 
       <action android:name="android.intent.action.MAIN" /> 

       <category android:name="android.intent.category.LAUNCHER" /> 
      </intent-filter> 
     </activity> 
     <activity 
      android:name=".MyActivity2" 
      android:label="@string/title_activity_my_activity2" > 
     </activity> 
    </application> 

</manifest> 

的錯誤我收到：

07-06 18:54:42.153 24145-24145/com.example.jms_m_000.transitionshit 
E/AndroidRuntime﹕FATAL EXCEPTION: main 

    Process: com.example.jms_m_000.transitionshit, PID: 24145 
    java.lang.IllegalStateException: Could not execute method of the activity 
      at android.view.View$1.onClick(View.java:3970) 
      at android.view.View.performClick(View.java:4598) 
      at android.view.View$PerformClick.run(View.java:19268) 
      at android.os.Handler.handleCallback(Handler.java:738) 
      at android.os.Handler.dispatchMessage(Handler.java:95) 
      at android.os.Looper.loop(Looper.java:135) 
      at android.app.ActivityThread.main(ActivityThread.java:5070) 
      at java.lang.reflect.Method.invoke(Native Method) 
      at java.lang.reflect.Method.invoke(Method.java:372) 
      at rnal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:836) 
      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:631) 
    Caused by: java.lang.reflect.InvocationTargetException 
      at java.lang.reflect.Method.invoke(Native Method) 
      at java.lang.reflect.Method.invoke(Method.java:372) 
      at android.view.View$1.onClick(View.java:3965) 
at android.view.View.performClick(View.java:4598) 
at android.view.View$PerformClick.run(View.java:19268) 
at android.os.Handler.handleCallback(Handler.java:738) 
at android.os.Handler.dispatchMessage(Handler.java:95) 
at android.os.Looper.loop(Looper.java:135) 
at android.app.ActivityThread.main(ActivityThread.java:5070) 
at java.lang.reflect.Method.invoke(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:372) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:836) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:631) 
    Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.os.Bundle android.app.ActivityOptions.toBundle()' on a null object reference 
      at com.example.jms_m_000.transitionshit.MyActivity.showPhoto(MyActivity.java:56) 
at java.lang.reflect.Method.invoke(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:372) 
at android.view.View$1.onClick(View.java:3965) 
at android.view.View.performClick(View.java:4598) 
at android.view.View$PerformClick.run(View.java:19268) 
at android.os.Handler.handleCallback(Handler.java:738) 
at android.os.Handler.dispatchMessage(Handler.java:95) 
at android.os.Looper.loop(Looper.java:135) 
at android.app.ActivityThread.main(ActivityThread.java:5070) 
at java.lang.reflect.Method.invoke(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:372) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:836) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:631) 

林不知道爲什麼，但選項是空調用.makeSceneTransitionAnimation()後...

有什麼想法？

Answer 1

通過在第一個Activity中調用setViewName（）到'hero'來定義一個視圖名稱，並在第二個Activity中爲您的ImageView定義一個視圖名稱（與makeSceneTransitionAnimation中定義的相同）。這是爲我工作

Answer 2

嘗試在活動的onCreate（）方法將

requestFeature(Window.FEATURE_CONTENT_TRANSITIONS); 

。

令人驚訝的是，我使選項非空。