匯入資源中定義的物件陣列

在某些情況下,需要在應用程式的資源中建立和定義自定義物件。這些物件可以由 Java 簡單型別組成,例如 IntegerFloatString

以下是如何匯入應用程式資源中定義的物件的示例。物件 Category 包含 3 個屬性:

  • ID
  • 顏色
  • 名稱

這個 POJOcategories.xml 檔案中具有相同的功能,其中每個陣列都具有為每個類別定義的相同屬性。

  1. 為你的物件建立模型:
public class Category {
    private Type id;
    private @ColorRes int color;
    private @StringRes String name;

    public Category getId() {
        return id;
    }

    public void setId(Category id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getColor() {
        return color;
    }

    public void setColor(int color) {
        this.color = color;
    }

    public enum Type{
        REGISTRATION,
        TO_ACCEPT,
        TO_COMPLETE,
        TO_VERIFY,
        CLOSED
    }
}
  1. res/values 資料夾中建立檔案:

categories.xml

  1. 撰寫由資源組成的每個模型:
<array name="no_action">
    <item>0</item>
    <item>@android:color/transparent</item>
    <item>@string/statusRegistration</item>
</array>
<array name="to_accept">
    <item>1</item>
    <item>@color/light_gray</item>
    <item>@string/acceptance</item>
</array>
<array name="opened">
    <item>2</item>
    <item>@color/material_green_500</item>
    <item>@string/open</item>
</array>
<array name="to_verify">
    <item>3</item>
    <item>@color/material_gray_800</item>
    <item>@string/verification</item>
</array>
<array name="to_close">
    <item>4</item>
    <item>@android:color/black</item>
    <item>@string/closed</item>
</array>
  1. 在資原始檔中定義一個陣列:

    <array name="categories">
        <item>@array/no_action</item>
        <item>@array/to_accept</item>
        <item>@array/opened</item>
        <item>@array/to_verify</item>
        <item>@array/to_close</item>
    </array>
    
  2. 建立一個匯入它們的函式:

    @NonNull
    public List<Category> getCategories(@NonNull Context context) {
    final int DEFAULT_VALUE = 0;
    final int ID_INDEX = 0;
    final int COLOR_INDEX = 1;
    final int LABEL_INDEX = 2;
    
    if (context == null) {
        return Collections.emptyList();
    }
    // Get the array of objects from the `tasks_categories` array
    TypedArray statuses = context.getResources().obtainTypedArray(R.array.categories);
    if (statuses == null) {
        return Collections.emptyList();
    }
    List<Category> categoryList = new ArrayList<>();
    for (int i = 0; i < statuses.length(); i++) {
        int statusId = statuses.getResourceId(i, DEFAULT_VALUE);
        // Get the properties of one object
        TypedArray rawStatus = context.getResources().obtainTypedArray(statusId);
    
        Category category = new Category();
    
        int id = rawStatus.getInteger(ID_INDEX, DEFAULT_VALUE);
        Category.Type categoryId;
        //The ID's should maintain the order with `Category.Type`
        switch (id) { 
            case 0:
                categoryId = Category.Type.REGISTRATION;
                break;
            case 1:
                categoryId = Category.Type.TO_ACCEPT;
                break;
            case 2:
                categoryId = Category.Type.TO_COMPLETE;
                break;
            case 3:
                categoryId = Category.Type.TO_VERIFY;
                break;
            case 4:
                categoryId  = Category.Type.CLOSED;
                break;
            default:
                categoryId = Category.Type.REGISTRATION;
                break;
        }
        category.setId(categoryId);
    
        category.setColor(rawStatus.getResourceId(COLOR_INDEX, DEFAULT_VALUE));
    
        int labelId = rawStatus.getResourceId(LABEL_INDEX, DEFAULT_VALUE);
        category.setName(getString(context.getResources(), labelId));
    
        categoryList.add(taskCategory);
    }
    return taskCategoryList;
    }