android - 更改 ArrayAdapter 的值

Question

如果选择了第一个元素，我想更新我的 ArrayAdapter 的值:

public ArrayAdapter<String> adapter;
String[] categoriesArray;    
...

adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, categoriesArray);
list.setAdapter(adapter);

list.setOnItemClickListener(new OnItemClickListener(){
    @Override
    public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
        if(arg2== Consts.GAME_CATEGORY_POSITION){

            adapter.clear();

            //Add new values to array
            categoriesArray = new String[subCategories.size()];
            for (int i=0; i<subCategories.size(); i++) {
                categoriesArray[i] = subCategories.get(i).getSub_name();                    
            }           
            adapter.notifyDataSetChanged();             
        }           
    }           
});

但是clear方法(适配器)触发了异常

12-27 09:37:57.376: E/AndroidRuntime(1423): java.lang.UnsupportedOperationException
12-27 09:37:57.376: E/AndroidRuntime(1423):     at java.util.AbstractList.remove(AbstractList.java:638)
12-27 09:37:57.376: E/AndroidRuntime(1423):     at java.util.AbstractList$SimpleListIterator.remove(AbstractList.java:75)
12-27 09:37:57.376: E/AndroidRuntime(1423):     at java.util.AbstractList.removeRange(AbstractList.java:658)
12-27 09:37:57.376: E/AndroidRuntime(1423):     at java.util.AbstractList.clear(AbstractList.java:466)
12-27 09:37:57.376: E/AndroidRuntime(1423):     at android.widget.ArrayAdapter.clear(ArrayAdapter.java:258)

有什么想法吗？

感谢阅读。

Answer 1

将您自己的列表而不是数组传递给适配器。适配器使用 Arrays.asList 方法将数组转换为列表，此方法返回的列表不支持删除。您可以从数组中创建 ArrayList 的实例并将其传递给适配器:

List<String> values = new ArrayList<String>(Arrays.asList(categoriesArray));
adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, values);

但最好检查@PrafulBhatnagar 提到的非常相似的问题:Unable to modify ArrayAdapter in ListView: UnsupportedOperationException