Android：如何從外部bindView（）方法訪問viewHolder？

Question

下面是我想要實現的示例代碼。

public class ToDoCursorAdapter extends CursorAdapter { 
    ...... 

    public ToDoCursorAdapter(Context context, Cursor cursor) { 
     super(context, cursor, 0); 
    } 

    @Override 
    public View newView(Context context, Cursor cursor, ViewGroup parent) { 

     ViewHolderItem viewHolder = new ViewHolderItem(); 
     View rowView = LayoutInflater.from(context).inflate(R.layout.listview, parent, false); 

     viewHolder.refTextV = (TextView) rowView.findViewById(R.id.refText); 
     viewHolder.buttonIRV = (Button) rowView.findViewById(R.id.buttonIR); //For Ref Text 
     ..... 

     rowView.setTag(viewHolder); 
     return rowView; 
    } 

    @Override 
    public void bindView(final View view, final Context context, final Cursor cursor) { 
     final ViewHolderItem viewHolder = (ViewHolderItem) view.getTag(); 

     ...... 

     viewHolder.refTextV.setText(ref); 

     ...... 
    } 

    public void hideShowAll(Button but) { 

     //I want to be able to acess BUTTONS/TEXTVIWEs from this function. 
     // Like viewHolder.refTextV.setText(ref) in binView 

     Toast.makeText(mContext, "Hello" , Toast.LENGTH_SHORT).show(); 
    } 
} 

我試圖在適配器內從另一個函數訪問的視圖元素，如Button，TextView在bindView。

另外，如果可以的話，請添加一點解釋，以便我能夠理解它的工作原理，並可能爲未來學習某些內容。

謝謝

更新

我終於在我的hideShowAll()使用notifyDataSetChanged();而不是在那裏訪問ViewHolder。我將更改存儲在數組中，然後調用notifyDataSetChanged()。它刷新了我的觀點，並根據陣列反映了我想要做出的更改。

此外，我有問題得到它爲我工作，因爲這裏提到的一些意見宣稱ViewHoldernewView之後Constructor。這不是一個好主意。你會得到錯誤的ViewHolder，而不是屬於某一行的。

Answer 1

試圖聲明「ViewHolderItem viewHolder」下面的構造函數和所有覆蓋方法之外，並初始化成bindView方法

Answer 2

首先，初始化ViewHolderItem全球範圍內，那麼你可以訪問諸如Button，TextView等你的看法在另一個method這樣。

public class ToDoCursorAdapter extends CursorAdapter { 
    ...... 
// initialize ViewHolderItem here 
ViewHolderItem viewHolder = new ViewHolderItem(); 
@Override 
    public View newView(Context context, Cursor cursor, ViewGroup parent) { 
     //remove this line here 
     // ViewHolderItem viewHolder = new ViewHolderItem(); 
     View rowView = LayoutInflater.from(context).inflate(R.layout.listview, parent, false); 

     viewHolder.refTextV = (TextView) rowView.findViewById(R.id.refText); 
     viewHolder.buttonIRV = (Button) rowView.findViewById(R.id.buttonIR); //For Ref Text 
     ..... 

     rowView.setTag(viewHolder); 
     return rowView; 
    } 

public void hideShowAll(Button but) { 

     //call it like this and do what you want 
     viewHolder.buttonIRV.setEnabled(false); 
     Toast.makeText(mContext, "Hello" , Toast.LENGTH_SHORT).show(); 
    } 

希望它能幫助你。

Answer 3

試試這個：

public class ToDoCursorAdapter extends CursorAdapter { 
...... 

public ToDoCursorAdapter(Context context, Cursor cursor) { 
    super(context, cursor, 0); 
} 

@Override 
public View newView(Context context, Cursor cursor, ViewGroup parent) { 

    ViewHolderItem viewHolder = new ViewHolderItem(); 
    View rowView = LayoutInflater.from(context).inflate(R.layout.listview, parent, false); 

    viewHolder.refTextV = (TextView) rowView.findViewById(R.id.refText); 
    viewHolder.buttonIRV = (Button) rowView.findViewById(R.id.buttonIR); //For Ref Text 
    ..... 

    rowView.setTag(viewHolder); 
    return rowView; 
} 

@Override 
public void bindView(final View view, final Context context, final Cursor cursor) { 
    final ViewHolderItem viewHolder = (ViewHolderItem) view.getTag(); 

    ...... 

    viewHolder.refTextV.setText(ref); 

    ...... 
} 

public void hideShowAll(Button but, ViewHolderItem viewHolder) { 

    //I want to be able to acess BUTTONS/TEXTVIWEs from this function. 
    viewHolder.refTextV.setText("hello"); 

    Toast.makeText(mContext, "Hello" , Toast.LENGTH_SHORT).show(); 
} 
}