Listview中的交替颜色

Question

在我的列表视图getView 我有这样的代码

if (position % 2 == 0) { v.setBackgroundColor(Color.BLUE); }

这就是它的输出

但是如果数据看起来像这样呢

我尝试了上面的代码，但它看起来像这样

但我需要是这样的。

我不知道出了什么问题，但颜色图案每组都交换。如何根据最后一种格式修复它。总是以蓝色开头

更新

ItemModel.java

public class ItemModel implements Comparable<ItemModel> {
    private boolean isSectionHeader;
    private String cusname;
    private String date;
}

public String getCusname() {
    return cusname;
}

public void setCusname(String cusname) {
    this.cusname = cusname;
}

public boolean isSectionHeader() {
    return isSectionHeader;
}

@Override
public int compareTo(ItemModel itemModel) {
    return this.date.compareTo(itemModel.date);
}

public void setToSectionHeader() {
    isSectionHeader = true;
}

public String getDate() {
    return date;
}

public void setDate(String date) {
    this.date = date;
}

public String getRemarks() {
    return remarks;
}


public ItemModel(String cusname, String remarks, String date) {
        this.isSectionHeader = isSectionHeader;
        this.cusname = cusname;
        this.remarks = remarks;
        this.date = date;
}

这是我将数据从 sqllite 传输到数组的地方

private ArrayList<ItemModel> getItems() {
    Cursor data = myDb.get_plan(pattern_email);
    ArrayList<ItemModel> items = new ArrayList<>();
    while (data.moveToNext()) {
        String cusname = data.getString(0);
        String remarks = data.getString(2);
        String date = data.getString(3);
        items.add(new ItemModel(cusname, remarks, date));
    }
    return items;
}

这是排序器并在列表视图中显示

private ArrayList sortAndAddSections(ArrayList<ItemModel> itemList) {

    ArrayList<ItemModel> tempList = new ArrayList<>();
    ArrayList<Integer> tmpHeaderPositions = new ArrayList<>();
    Collections.sort(itemList);
    ItemModel sectionCell;

    String header = "";
    int addedRow = 0;
    for (int i = 0; i < itemList.size(); i++) {
        if (!(header.equals(itemList.get(i).getDate()))) {
            String cusname = itemList.get(i).getCusname();
            String remarks = itemList.get(i).getRemarks();
            sectionCell = new ItemModel(cusname, remarks, date);
            sectionCell.setToSectionHeader();
            tmpHeaderPositions.add(i + addedRow);
            addedRow++;
            tempList.add(sectionCell);
            header = itemList.get(i).getDate();
        }
        tempList.add(itemList.get(i));
    }

    tmpHeaderPositions.add(tempList.size());
    for (int i = 0; i < tmpHeaderPositions.size() - 1; i++) {
        sectionCell = tempList.get(tmpHeaderPositions.get(i));
        sectionCell.setDate(sectionCell.getDate() + " (" +
                (tmpHeaderPositions.get(i + 1) - tmpHeaderPositions.get(i) - 1) + ")");
    }
    return tempList;
}

这是我的看法

public View getView(int position, View convertView, ViewGroup parent) {
  /* Alternating Colors*/
    LinearLayout line_others = v.findViewById(R.id.line_others);

    if (position % 2 == 0) {
        line_others.setBackgroundResource(R.color.red);
    } else {                         
        line_others.setBackgroundResource(R.color.alt_gray);
    }
}

Answer 1

以下是基于这里的答案：Alternating colors in listview but needs to have a starting color

1. 在 ItemModel 中添加一个新的 int 字段 bgColor 并创建 getter 和 setter 方法。

2. 变化：

   private ArrayList sortAndAddSections(ArrayList<ItemModel> itemList) {
   
       ArrayList<ItemModel> tempList = new ArrayList<>();
       ArrayList<Integer> tmpHeaderPositions = new ArrayList<>();
       Collections.sort(itemList);
       ItemModel sectionCell;
   
       String header = "";
       int addedRow = 0;
       int bgColor = R.color.red; //Added
       for (int i = 0; i < itemList.size(); i++) {
           if (!(header.equals(itemList.get(i).getDate()))) {
               String cusname = itemList.get(i).getCusname();
               String remarks = itemList.get(i).getRemarks();
               sectionCell = new ItemModel(cusname, remarks, date);
               sectionCell.setToSectionHeader();
               tmpHeaderPositions.add(i + addedRow);
               addedRow++;
               tempList.add(sectionCell);
               header = itemList.get(i).getDate();
               bgColor = R.color.red; //Added
           }
           sectionCell = itemList.get(i); //Added
           sectionCell.setBgColor(bgColor); //Added
           tempList.add(sectionCell); //Changed
           if (bgColor == R.color.red) bgColor = R.color.alt_gray; //Added
           else bgColor = R.color.red; //Added
       }
   
       tmpHeaderPositions.add(tempList.size());
       for (int i = 0; i < tmpHeaderPositions.size() - 1; i++) {
       sectionCell = tempList.get(tmpHeaderPositions.get(i));
       sectionCell.setDate(sectionCell.getDate() + " (" +
           (tmpHeaderPositions.get(i + 1) - tmpHeaderPositions.get(i) - 1) + ")");
       }
       return tempList;
   }
   

3. 更改适配器 getView()。不再计算背景颜色，只需使用数据项中的 bgColor 设置即可。

希望有帮助！

Answer 2

有一个名为 counter 的 int 变量，并在代码开头以及有新标头时将其设置为 0。

然后对于每一行将计数器加一，如果计数器是偶数，则将背景设为蓝色。

即。

counter = 0;

for each item in the list view {


if (isHeader) {

    counter  = 0;

} else {

    if (counter % 2 = 0) {

        background = blue;

    } 
    else {

        background = white;

    }
    counter++;
}

}