添加ListView項目與用戶輸入AlertDialog

Question

即時通訊嘗試填充一個ListView與AlertDialog的輸入，它打開一個EditText。我的問題是每次我在AlertDialog中用EditText給出一些東西，並從AlertDialog中單擊我的添加按鈕，它會用相同的String填充我的Array的所有20套。但是我希望他從EditText中填充字符串只有1時間，我可以用這個1項進一步工作。

這裏是我的代碼

MainActivity.java

public class MainActivity extends Activity { 

    private static final int DIALOG_ALERT = 10; 

    ListView list; 
    Button addBtn; 
    EditText input; 

    String[] items; 
    ArrayAdapter<String> adapter; 

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

     list = (ListView) findViewById(R.id.list); 
     addBtn = (Button) findViewById(R.id.addPlanBtn); 

     input = new EditText(this); 

     items = new String[20]; 

     adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, items); 
     list.setAdapter(adapter); 



     addBtn.setOnClickListener(new OnClickListener() { 

      @Override 
      public void onClick(View v) { 

       AlertDialog alert = new AlertDialog.Builder(MainActivity.this).create(); 
       alert.setTitle("Train plan name"); 
       alert.setMessage("enter a name:"); 
       alert.setView(input); 




       alert.setButton("add", new DialogInterface.OnClickListener() { 
        public void onClick(DialogInterface dialog, int which) { 
          String value = input.getText().toString(); 

          for(int i=0; i < items.length; i++){  
           items[i] = value; 

          } 

        } 
        }); 

        alert.show(); 
      } 


     }); 

    } 


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

} 

activity_main.xml中

<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" 
    tools:context=".MainActivity" > 

    <ListView 
     android:id="@+id/list" 
     android:layout_width="fill_parent" 
     android:layout_height="fill_parent" 
     android:layout_above="@+id/addPlanBtn" 
     > 

    </ListView> 

    <Button 
     android:id="@+id/addPlanBtn" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_alignParentBottom="true" 
     android:layout_alignParentLeft="true" 
     android:layout_alignParentRight="true" 
     android:text="add a new Plan" /> 

</RelativeLayout> 

感謝您的任何幫助。

Answer 1

for循環在你的點擊監聽器設置，underlies您的列表中的所有的數組成員的字符串：

for(int i=0; i < items.length; i++){  
    items[i] = value; 
} 

要改變只是在討論的這個字符串你要索引陣列的特定成員，例如：

items[0] = value; 

這將只更改第一項。在你的情況下，你拉起來的對話框並不是綁定到一個特定的列表項目，所以你必須想出一種跟蹤正在編輯哪個列表項目的方法。

Answer 2

瞭解它，

這裏是工作代碼。

MainActivity.java

public class MainActivity extends Activity { 

    private static final int DIALOG_ALERT = 10; 

    ListView list; 
    Button addBtn; 
    EditText input; 

    String[] items; 
    MyListAdapter adapter; 
    AlertDialog alert; 

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

     list = (ListView) findViewById(R.id.list); 
     addBtn = (Button) findViewById(R.id.addPlanBtn); 

     input = new EditText(this); 

     items = new String[1]; 





     alert = new AlertDialog.Builder(MainActivity.this).create(); 
     alert.setTitle("Train plan name"); 
     alert.setMessage("enter a name:"); 
     alert.setView(input); 


     alert.setButton("add", new DialogInterface.OnClickListener() { 

      public void onClick(DialogInterface dialog, int which) { 
        String value = input.getText().toString(); 

        items[items.length - 1] = value; 

        adapter = new MyListAdapter(MainActivity.this, items); 
        list.setAdapter(adapter); 

        String[] temp = new String[items.length +1]; 

        for(int i = 0; i< items.length; i++) 
         temp[i] = items[i]; 

        items = temp; 

        alert.dismiss(); 
        adapter.notifyDataSetChanged(); 
      } 

      }); 




     addBtn.setOnClickListener(new OnClickListener() { 

      @Override 
      public void onClick(View v) { 

        alert.show(); 
      } 


     }); 

    } 


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

} 

MyListAdapter

public class MyListAdapter extends ArrayAdapter<String> { 

    private final Context context; 
    private final String[] values; 

    static class ViewHolder { 
     public TextView text; 
    } 

    public MyListAdapter(Context context, String[] values) { 
     super(context, R.layout.row_item, values); 
     this.context = context; 
     this.values = values; 
    } 

    @Override 
     public View getView(int position, View convertView, ViewGroup parent) { 
     LayoutInflater inflater = (LayoutInflater) context 
      .getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
     View rowView = inflater.inflate(R.layout.row_item, parent, false); 
     TextView textView = (TextView) rowView.findViewById(R.id.tvItem); 
     textView.setText(values[position]); 

     return rowView; 
     } 


} 

row_item.xml

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

    <TextView 
     android:id="@+id/tvItem" 
     android:layout_width="fill_parent" 
     android:layout_height="50px" 
     android:textSize="40px" > 

    </TextView> 


</RelativeLayout> 

activity_main.xml中

<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" 
    tools:context=".MainActivity" > 

    <ListView 
     android:id="@+id/list" 
     android:layout_width="fill_parent" 
     android:layout_height="fill_parent" 
     android:layout_above="@+id/addPlanBtn" 
     > 

    </ListView> 

    <Button 
     android:id="@+id/addPlanBtn" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_alignParentBottom="true" 
     android:layout_alignParentLeft="true" 
     android:layout_alignParentRight="true" 
     android:text="add a new Plan" /> 

</RelativeLayout> 

謝謝大家，誰的時間來幫助我。