安卓在ListFragment中實現搜索

Question

我想在我的ListFragment中添加一個搜索功能。我在一個標準的Activity中完成了它，但是試圖將它移植到碎片上。 什麼我目前做的是這樣的：

1. 我有承載片段一個Main.java。

2. 我有一個主機與R.id.frag_list列表陣列List.TERM一個ListFrag.java

我Main.java實現addTextChangedListener這樣的：

et.addTextChangedListener(new TextWatcher() 
    { 
    public void afterTextChanged(Editable s) 
    { 
                    // Abstract Method of TextWatcher Interface. 
    } 
    public void beforeTextChanged(CharSequence s, 
    int start, int count, int after) 
    { 
    // Abstract Method of TextWatcher Interface. 
    } 
    public void onTextChanged(CharSequence s, 
    int start, int before, int count) 
    { 
    textlength = et.getText().length(); 
    array_sort.clear(); 
    for (int i = 0; i < List.TERM.length; i++) 
    { 
    if (textlength <= List.TERM[i].length()) 
    { 
    if(et.getText().toString().equalsIgnoreCase(
    (String) 
    List.TERM[i].subSequence(0, 
    textlength))) 
    {array_sort.add(List.TERM[i]); 
    } 
    } 
    } 
    lv.setAdapter(new ArrayAdapter<String> 
    (Main.this, 
      R.layout.main,R.id.frag_list, array_sort)); 
    } 
    }); 

和我main.xml中是這樣的：

<LinearLayout 
    android:layout_width="fill_parent" 
    android:background="@drawable/searchbar" 
    android:layout_height="60dp" 
    android:layout_marginLeft="15dp" 
    android:layout_marginRight="15dp" 
    > 
    <EditText android:id="@+id/EditText01" 
    android:layout_height="wrap_content" 
    android:layout_width="fill_parent" 
    android:hint="@string/prompt"> 
    </EditText> 
    </LinearLayout> 

<fragment 
    android:id="@+id/frag_list" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
android:layout_marginLeft="50dp" 
android:layout_marginTop="90dp" 
android:layout_marginBottom="40dp" 
    class="com.bernard.ListFrag" /> 

當我運行該應用程序時，我單擊editText。

08-11 12:59:57.090: E/AndroidRuntime(20220): FATAL EXCEPTION: main 
08-11 12:59:57.090: E/AndroidRuntime(20220): java.lang.NullPointerException 
08-11 12:59:57.090: E/AndroidRuntime(20220): at com.bernard.Main$1.onTextChanged(Main.java:54) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at android.widget.TextView.sendOnTextChanged(TextView.java:8105) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at android.widget.TextView.handleTextChanged(TextView.java:8152) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at android.widget.TextView$ChangeWatcher.onTextChanged(TextView.java:8532) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at android.text.SpannableStringBuilder.sendTextChange(SpannableStringBuilder.java:892) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at android.text.SpannableStringBuilder.change(SpannableStringBuilder.java:352) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at android.text.SpannableStringBuilder.change(SpannableStringBuilder.java:266) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at android.text.SpannableStringBuilder.replace(SpannableStringBuilder.java:443) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at android.text.SpannableStringBuilder.replace(SpannableStringBuilder.java:420) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at android.text.SpannableStringBuilder.replace(SpannableStringBuilder.java:29) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at android.view.inputmethod.BaseInputConnection.replaceText(BaseInputConnection.java:669) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at android.view.inputmethod.BaseInputConnection.setComposingText(BaseInputConnection.java:431) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at com.android.internal.view.IInputConnectionWrapper.executeMessage(IInputConnectionWrapper.java:369) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at com.android.internal.view.IInputConnectionWrapper$MyHandler.handleMessage(IInputConnectionWrapper.java:85) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at android.os.Handler.dispatchMessage(Handler.java:99) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at android.os.Looper.loop(Looper.java:156) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at android.app.ActivityThread.main(ActivityThread.java:5025) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at java.lang.reflect.Method.invokeNative(Native Method) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at java.lang.reflect.Method.invoke(Method.java:511) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551) 
08-11 12:59:57.090: E/AndroidRuntime(20220): at dalvik.system.NativeStart.main(Native Method) 

我對這樣的錯誤的猜測是：

1. 我應該片段下實現EDITTEXT和文字聽衆和我試着鍵入一個字母的瞬間，應用程序錯誤日誌崩潰不是Main.java。
2. 我不是從Main.java調用新的列表，因此是一個NullPointerException。

任何人有建議來解決這個問題？謝謝:)

Answer 1

發現瞭如何做我自己！感謝尼克的幫助：D

這有點粗糙，但它的工作原理。如果您認爲自己有更好的解決方案，請分享！

所以我所做的就是創建一個列表片段http://developer.android.com/guide/components/fragments.html#CommunicatingWithActivity

查看片段視圖根據該示例訣竅是，在ListFrag.java，我簡單地實現我的onCreateView下原來的活動應有盡有。 重要的部分是如下：

@Override 
public View onCreateView(LayoutInflater inflater, ViewGroup container, 
     Bundle savedInstanceState) { 
    // Inflate the layout for this fragment 
    final View V = inflater.inflate(R.layout.list_fragment, container, false); 

    lv = (ListView) V.findViewById(R.id.ListView01); 
    final ArrayList <String>ar = new ArrayList<String>(); 
    et = (EditText) V.findViewById(R.id.EditText01); 
    final String[] words = list.TERM; 
    // Populate list with our static array of titles. 
    lv.setAdapter(new ArrayAdapter<String>(getActivity(), 
      android.R.layout.simple_list_item_activated_1, list.TERM)); 
    lv.setTextFilterEnabled(true); 

    et.addTextChangedListener(new TextWatcher() 
    { 
    public void afterTextChanged(Editable s) 
    { 
                    // Abstract Method of TextWatcher Interface. 
    } 
    public void beforeTextChanged(CharSequence s, 
    int start, int count, int after) 
    { 
    // Abstract Method of TextWatcher Interface. 
    } 
    public void onTextChanged(CharSequence s, 
    int start, int before, int count) 
    { 
    textlength = et.getText().length(); 
    array_sort.clear(); 
    for (int i = 0; i < words.length; i++) 
    { 
    if (textlength <= words[i].length()) 
    { 
    if(et.getText().toString().equalsIgnoreCase(
    (String) 
    words[i].subSequence(0, 
    textlength))) 
    {array_sort.add(words[i]); 
    } 
    } 
    } 
    lv.setAdapter(new ArrayAdapter<String> 
    (getActivity(), 
      android.R.layout.simple_list_item_activated_1, array_sort)); 
    } 
    }); 

    //Intent after selection is made 
    lv.setOnItemClickListener(new OnItemClickListener() { 
     @Override 
     public void onItemClick(AdapterView<?> parent, View view, 
       int position, long id) { 
      String name = lv.getItemAtPosition(position).toString(); 
      for (int index = 0; index < words.length; index++) 
      { 
       if (name.equals(words[index])) 
       { 
        position = index; 
        break; 
       } 
      } 
      String d1 = words[position]; 
      ar.add(d1.toString()); 

      showDetails(position); 

     } 
    }); 



    return V; 
} 

有你有它，在裏面的片段列表視圖全搜索。

Answer 2

嘗試更換：

for (int i = 0; i < List.TERM.length; i++) 
    { 
    if (textlength <= List.TERM[i].length()) 
    { 
    if(et.getText().toString().equalsIgnoreCase(
    (String) 
    List.TERM[i].subSequence(0, 
    textlength))) 
    {array_sort.add(List.TERM[i]); 
    } 
    } 
    } 
    lv.setAdapter(new ArrayAdapter<String> 
    (Main.this, 
      R.layout.main,R.id.frag_list, array_sort)); 
    } 
    }); 

有：

  // reuse the existing adapter instead of creating a new one: 
      ArrayAdapter<String> ad = (ArrayAdapter<String>) getListView().getAdapter(); 
      ad.clear(); 
      for (int i = 0; i < List.TERM.length; i++) { 
       if (textlength <= List.TERM[i].length()) { 
       if (et.getText().toString().equalsIgnoreCase(
         (String) 
          List.TERM[i].subSequence(0, 
            textlength))) { 
        ad.add(List.TERM[i]); 
       } 
       } 
      } 
      ad.notifyDataSetChanged(); // tell the ListView to update