基於內容/變量更改listitem背景

Question

我有一個自定義適配器的列表，並希望根據列表項或變量的內容設置背景顏色。 該列表由包含日期和一些信息的文本視圖組成。

我需要的背景顏色時，將顯示一個新的日期來改變..

物品1：2，2016年3月 - >藍

ITEM2：2. 2016年3月 - >藍

項目3 ：3，2016年3月 - >灰色

ITEM4：4，2016年3月 - >藍

...

我可以設置一個可以在listAdapter中使用的變量（isNewDate）嗎？

我的目錄適配器：

public class HistoryListViewAdapter extends ArrayAdapter<HistoryListItem> { 

     public HistoryListViewAdapter(Context context, List<HistoryListItem> items) { 
      super(context, R.layout.history_list_item, items); 
     } 

     @Override 
     public View getView(int position, View convertView, ViewGroup parent) { 
      ViewHolder viewHolder; 

      if(convertView == null) { 
       // inflate the ListView item layout 
       LayoutInflater inflater = LayoutInflater.from(getContext()); 
       convertView = inflater.inflate(R.layout.history_list_item, parent, false); 
       //different color if new date 

       if (newdate == 0) //How to find if it is a "new date" 
        //togle color 

       convertView.setBackgroundColor(ContextCompat.getColor(getContext(), R.color.colorPrimaryDark)); 

       // initialize the view holder 
       viewHolder = new ViewHolder(); 
       viewHolder.ivIcon = (ImageView) convertView.findViewById(R.id.ivIcon); 
       viewHolder.tvTextfield = (TextView) convertView.findViewById(R.id.tvTextfield); 
       viewHolder.tvNote = (ImageView) convertView.findViewById(R.id.tvNote); 
       convertView.setTag(viewHolder); 
      } else { 
       // recycle the already inflated view 
       viewHolder = (ViewHolder) convertView.getTag(); 
      } 

      // update the item view 
      HistoryListItem item = getItem(position); 
      viewHolder.ivIcon.setImageDrawable(item.icon); 
      viewHolder.tvTextfield.setText(item.textfield); 
      viewHolder.tvNote.setImageDrawable(item.note); 

      return convertView; 
     } 

     private static class ViewHolder { 
      ImageView ivIcon; 
      TextView tvTextfield; 
      ImageView tvNote; 
     } 
    } 

Answer 1

您需要添加varible存儲日期在HistoryListItem模型類。 然後你的適配器類將如下所示。

public class HistoryListViewAdapter extends ArrayAdapter<HistoryListItem> { 

//Varible to STORE current Date value 
String previousDate = null ; 

     public HistoryListViewAdapter(Context context, List<HistoryListItem> items) { 
      super(context, R.layout.history_list_item, items); 
     } 

     @Override 
     public View getView(int position, View convertView, ViewGroup parent) { 
      ViewHolder viewHolder; 

      if(convertView == null) { 
       // inflate the ListView item layout 
       LayoutInflater inflater = LayoutInflater.from(getContext()); 
       convertView = inflater.inflate(R.layout.history_list_item, parent, false); 
       //different color if new date 

       //This is how you How to find if it is a "new date" 
       if(null== previousDate || !item.dateField.equalIgnorecase(previousDate)) 
{ 
//Store current date as previous date 
previousDate = item.dateField ; 

//TODO add togle color logic here 
} 


       convertView.setBackgroundColor(ContextCompat.getColor(getContext(), R.color.colorPrimaryDark)); 

       // initialize the view holder 
       viewHolder = new ViewHolder(); 
       viewHolder.ivIcon = (ImageView) convertView.findViewById(R.id.ivIcon); 
       viewHolder.tvTextfield = (TextView) convertView.findViewById(R.id.tvTextfield); 
       viewHolder.tvNote = (ImageView) convertView.findViewById(R.id.tvNote); 
       convertView.setTag(viewHolder); 
      } else { 
       // recycle the already inflated view 
       viewHolder = (ViewHolder) convertView.getTag(); 
      } 

      // update the item view 
      HistoryListItem item = getItem(position); 
      viewHolder.ivIcon.setImageDrawable(item.icon); 
      viewHolder.tvTextfield.setText(item.textfield); 
      viewHolder.tvNote.setImageDrawable(item.note); 

      return convertView; 
     } 

     private static class ViewHolder { 
      ImageView ivIcon; 
      TextView tvTextfield; 
      ImageView tvNote; 
     } 
    }