如果我使用不同的ViewItemTypes，我應該使用viewHolders嗎？

Question

我最初的問題是張貼在這裏：

ListView for messaging app shows wrong listItem layout after scrolling

但我有點糊塗了，因爲有被upvoted這兩個答案，我想使用這兩者。首先，我認爲這是一個安全的假設，我應該使用getItemViewType方法來幫助我提高性能。但在此之後，我是否仍然使用Making ListView Scrolling Smooth上的Google文檔中描述的viewHolder模式？

如果我使用ViewHolder代碼，是否將它合併到getView中？

static class ViewHolder { 
    TextView text; 
    TextView timestamp; 
    ImageView icon; 
    ProgressBar progress; 
    int position; 
} 

static public enum LAYOUT_TYPE { 
    INBOUND, 
    OUTBOUND 
} 

@Override 
public int getViewTypeCount() { 
    return LAYOUT_TYPE.values().length; 
} 

@Override 
public int getItemViewType (int position) { 
    if (messages.get(position).isOutbound()) 
     return LAYOUT_TYPE.OUTBOUND.ordinal(); 
    else 
     return LAYOUT_TYPE.INBOUND.ordinal(); 
} 

@Override 
public View getView (int position, View convertView, ViewGroup parent) { 
    LAYOUT_TYPE itemType = LAYOUT_TYPE.values()[getItemViewType(position)]; 
    ... (code until inflater) 
    switch (itemType){ 
    case INBOUND: 
      convertview = /inflate & configure inbound layout 
    ViewHolder holder = new ViewHolder(); 
    holder.icon = (ImageView) convertView.findViewById(R.id.listitem_image); 
    holder.text = (TextView) convertView.findViewById(R.id.listitem_text); 
    holder.timestamp = (TextView) convertView.findViewById(R.id.listitem_timestamp); 
    holder.progress = (ProgressBar) convertView.findViewById(R.id.progress_spinner); 
    convertView.setTag(holder); 
      break; 
    case OUTBOUND: 
      convertview = /inflate & configure outbound layout 
    ViewHolder holder = new ViewHolder(); 
    holder.icon = (ImageView) convertView.findViewById(R.id.listitem_image); 
    holder.text = (TextView) convertView.findViewById(R.id.listitem_text); 
    holder.timestamp = (TextView) convertView.findViewById(R.id.listitem_timestamp); 
    holder.progress = (ProgressBar) convertView.findViewById(R.id.progress_spinner); 
    convertView.setTag(holder); 
      break; 
    } 

Answer 1

//典型getView

public View getView(int position, View containerRow, ViewGroup parent) { 

if (containerRow == null) { 

    //One time inflate 
    containerRow = inflater.inflate(R.layout.yourLayout, parent, false); 

    //instantiate all view from layout in levent relevent object. 

    //One time instantiation of viewholder 
    viewHolder = new ViewHolder(); 

    viewHolder.someview = viewFromLayou; 

    //finally 
    containerRow.setTag(viewHolder); 
} 
else{ 
    viewHolder = (ViewHolder) containerRow.getTag(); 
} 
} 

//你的情況應該是

public View getView(int position, View containerRow, ViewGroup parent) { 

if (containerRow == null) { 

    //One time inflate 
    containerRow = inflater.inflate(R.layout.yourLayout, parent, false); 

    //instantiate all view from layout in levent relevent object. 

    //One time instantiation of viewholder 
    if(inbound) 
     inBoundViewHolder = new ViewHolder(); 
    else    
     outBoundViewHolder = new ViewHolder(); 

    viewHolder.someview = viewFromLayou; 

    //finally 
    containerRow.setTag(viewHolder); 
} 
else{ 
    viewHolder = (ViewHolder) containerRow.getTag(); 
} 
}