ClickListenerでviewById（）を見つける

Question

私は、水平に置かれた上部に4つのボタンを持ち、水平にスクロール可能なアンドロイドプログラムを書いています。これらのボタンの下にリストビューがあります。上記のいずれかのボタンをクリックすると、データが下のリストビューに表示されます。

public class ListActivity extends Activity { 
    /** Called when the activity is first created. */ 
    Context context=this; 
    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.main); 

     Button button1=(Button) findViewById(R.id.login); 
     Button button2=(Button) findViewById(R.id.login1); 
     Button button3=(Button) findViewById(R.id.login2); 
     Button button4=(Button) findViewById(R.id.login3); 
     button1.setOnClickListener(new OnClickListener(){ 
      @Override 
      public void onClick(View v) 
      { 
       try{ListView listView = (ListView) findViewById(R.id.mylist); 
       listView.setTextFilterEnabled(true); 

       String[] values = new String[] { "Android", "iPhone", "WindowsMobile", 
        "Blackberry", "WebOS", "Ubuntu", "Windows7", "Max OS X", 
        "Linux", "OS/2" ,"asdsad","asdsdsa","asdasdsa"}; 
       ArrayAdapter<String> adapter = new ArrayAdapter<String>(context, 
         R.layout.list_item,values); 

        // Assign adapter to ListView 
        listView.setAdapter(adapter);} 
       catch(Exception e){} 
      } 

     }); 



    } 
} 

がここにmain.xmlのための私のxmlファイルです：
はここに私の活動です。

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent" 
    android:orientation="vertical" > 

    <HorizontalScrollView xmlns:android="http://schemas.android.com/apk/res/android" 
     android:layout_width="wrap_content" android:layout_height="fill_parent"> 
    <LinearLayout 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:orientation="horizontal" 
     > 

     <Button 
     android:id="@+id/login" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:text="thisisbutton1" /> 

     <Button 
      android:id="@+id/login1" 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:text="thisisbutton2"/> 
       <Button 
      android:id="@+id/login2" 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:text="thisisbutton3"/> 

         <Button 
      android:id="@+id/login3" 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:text="thisisbutton4"/> 
    </LinearLayout>   
     </HorizontalScrollView> 



    <TextView 
     android:layout_width="fill_parent" 
     android:layout_height="wrap_content" 
     android:text="@string/hello" /> 
    <ListView 
     android:id="@+id/mylist" 
     android:layout_width="fill_parent" 
     android:layout_height="wrap_content" > 
    </ListView> 


</LinearLayout> 

はエラー（onClickListenerイベントの外に置かれたときにリストビューがうまく働いていた）はありません。しかし、実行時に次のエラーが表示されます。

03-03 20:42:01.604: D/AndroidRuntime(401): >>>>>>>>>>>>>> AndroidRuntime START <<<<<<<<<<<<<< 
03-03 20:42:01.604: D/AndroidRuntime(401): CheckJNI is ON 
03-03 20:42:01.974: D/AndroidRuntime(401): --- registering native functions --- 
03-03 20:42:02.744: D/ddm-heap(401): Got feature list request 
03-03 20:42:03.494: D/PackageParser(60): Scanning package: /data/app/vmdl57341.tmp 
03-03 20:42:03.844: D/dalvikvm(60): GC freed 6304 objects/322096 bytes in 289ms 
03-03 20:42:03.844: I/dalvikvm-heap(60): Grow heap (frag case) to 5.694MB for 16400-byte allocation 
03-03 20:42:04.064: D/dalvikvm(60): GC freed 120 objects/3784 bytes in 223ms 
03-03 20:42:04.225: I/PackageManager(60): Removing non-system package:com.list 
03-03 20:42:04.225: D/PackageManager(60): Removing package com.list 
03-03 20:42:04.225: D/PackageManager(60): Activities: com.list.ListActivity 
03-03 20:42:04.384: D/PackageManager(60): Scanning package com.list 
03-03 20:42:04.394: I/PackageManager(60): /data/app/vmdl57341.tmp changed; unpacking 
03-03 20:42:04.414: D/installd(32): DexInv: --- BEGIN '/data/app/vmdl57341.tmp' --- 
03-03 20:42:04.874: D/dalvikvm(407): DexOpt: load 67ms, verify 196ms, opt 4ms 
03-03 20:42:04.894: D/installd(32): DexInv: --- END '/data/app/vmdl57341.tmp' (success) --- 
03-03 20:42:04.894: D/PackageManager(60): Activities: com.list.ListActivity 
03-03 20:42:04.914: D/ActivityManager(60): Uninstalling process com.list 
03-03 20:42:04.914: D/ActivityManager(60): Force removing process ProcessRecord{44e56498 370:com.list/10031} (com.list/10031) 
03-03 20:42:04.914: I/Process(60): Sending signal. PID: 370 SIG: 9 
03-03 20:42:04.985: D/ActivityManager(60): Received spurious death notification for thread android.os.BinderProxy@44e14da8 
03-03 20:42:05.144: I/installd(32): move /data/dalvik-cache/data@app@vmdl57341.tmp@classes.dex -> /data/dalvik-cache/data@app@com.list.apk@classes.dex 
03-03 20:42:05.155: D/PackageManager(60): New package installed in /data/app/com.list.apk 
03-03 20:42:05.604: D/AndroidRuntime(401): Shutting down VM 
03-03 20:42:05.624: D/dalvikvm(401): DestroyJavaVM waiting for non-daemon threads to exit 
03-03 20:42:05.634: D/dalvikvm(401): DestroyJavaVM shutting VM down 
03-03 20:42:05.644: D/dalvikvm(401): HeapWorker thread shutting down 
03-03 20:42:05.644: D/dalvikvm(401): HeapWorker thread has shut down 
03-03 20:42:05.644: D/jdwp(401): JDWP shutting down net... 
03-03 20:42:05.644: I/dalvikvm(401): Debugger has detached; object registry had 1 entries 
03-03 20:42:05.655: D/dalvikvm(401): VM cleaning up 
03-03 20:42:05.674: D/dalvikvm(60): GC freed 3156 objects/236576 bytes in 358ms 
03-03 20:42:05.674: D/ActivityManager(60): Uninstalling process com.list 
03-03 20:42:05.704: E/AndroidRuntime(401): ERROR: thread attach failed 
03-03 20:42:05.734: D/dalvikvm(401): LinearAlloc 0x0 used 623916 of 5242880 (11%) 
03-03 20:42:06.605: D/dalvikvm(60): GC freed 1211 objects/76088 bytes in 453ms 
03-03 20:42:06.714: W/ResourceType(60): Resources don't contain package for resource number 0x7f0700e5 
03-03 20:42:06.725: W/ResourceType(60): Resources don't contain package for resource number 0x7f020031 
03-03 20:42:06.725: W/ResourceType(60): Resources don't contain package for resource number 0x7f020030 
03-03 20:42:06.725: W/ResourceType(60): Resources don't contain package for resource number 0x7f050000 
03-03 20:42:06.914: W/ResourceType(60): Resources don't contain package for resource number 0x7f060000 
03-03 20:42:06.964: W/ResourceType(60): Resources don't contain package for resource number 0x7f060001 
03-03 20:42:07.255: D/dalvikvm(106): GC freed 96 objects/3776 bytes in 586ms 
03-03 20:42:07.604: W/ResourceType(60): Resources don't contain package for resource number 0x7f0700e5 
03-03 20:42:07.614: W/ResourceType(60): Resources don't contain package for resource number 0x7f020031 
03-03 20:42:07.614: W/ResourceType(60): Resources don't contain package for resource number 0x7f020030 
03-03 20:42:07.614: W/ResourceType(60): Resources don't contain package for resource number 0x7f050000 
03-03 20:42:07.654: W/ResourceType(60): Resources don't contain package for resource number 0x7f060000 
03-03 20:42:07.664: W/ResourceType(60): Resources don't contain package for resource number 0x7f060001 
03-03 20:42:08.165: D/AndroidRuntime(412): CheckJNI is ON 
03-03 20:42:08.974: D/AndroidRuntime(412): --- registering native functions --- 
03-03 20:42:09.764: D/ddm-heap(412): Got feature list request 
03-03 20:42:10.425: I/ActivityManager(60): Starting activity: Intent { act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] flg=0x10000000 cmp=com.list/.ListActivity } 
03-03 20:42:10.545: I/ActivityManager(60): Start proc com.list for activity com.list/.ListActivity: pid=418 uid=10031 gids={} 
03-03 20:42:10.555: D/AndroidRuntime(412): Shutting down VM 
03-03 20:42:10.555: D/dalvikvm(412): DestroyJavaVM waiting for non-daemon threads to exit 
03-03 20:42:10.564: D/dalvikvm(412): DestroyJavaVM shutting VM down 
03-03 20:42:10.577: D/dalvikvm(412): HeapWorker thread shutting down 
03-03 20:42:10.577: D/dalvikvm(412): HeapWorker thread has shut down 
03-03 20:42:10.577: D/jdwp(412): JDWP shutting down net... 
03-03 20:42:10.577: I/dalvikvm(412): Debugger has detached; object registry had 1 entries 
03-03 20:42:10.577: D/dalvikvm(412): VM cleaning up 
03-03 20:42:10.625: E/AndroidRuntime(412): ERROR: thread attach failed 
03-03 20:42:10.684: D/dalvikvm(412): LinearAlloc 0x0 used 639500 of 5242880 (12%) 
03-03 20:42:10.964: D/ddm-heap(418): Got feature list request 
03-03 20:42:12.085: I/ActivityManager(60): Displayed activity com.list/.ListActivity: 1555 ms (total 1555 ms) 
03-03 20:42:17.344: D/dalvikvm(230): GC freed 76 objects/3256 bytes in 183ms 
03-03 20:42:22.534: D/dalvikvm(106): GC freed 2394 objects/139216 bytes in 289ms 
03-03 20:43:32.094: D/dalvikvm(103): GC freed 11873 objects/524240 bytes in 153ms 

何が問題なのですか。それを修正する方法はありますか？

Answer 1

私は自分の質問に答えます。実際には答えはロジックやコードではなく、main.xmlファイル（レイアウト）にあります。上記のmain.xmlファイルの水平スクロールビューでこれを変更してください。

android:layout_height="wrap_content" 

から

android:layout_height="fill_parent" 

それは正常に動作します。リストビューは、最初のボタンをクリックすると表示されます。