ArrayAdapter 尝试通过调用Object.toString()-method 将您的Location 对象显示为字符串（这会导致十六进制值）。它的默认实现返回：
[...] 由类的名称组成的字符串，其中对象
是一个实例，at-sign 字符 `@'，以及无符号
对象哈希码的十六进制表示。
要使ArrayAdadpter 在项目列表中显示一些实际有用的内容，您可以覆盖toString()-方法以返回有意义的内容：
@Override
public String toString(){
return "Something meaningful here...";
}
另一种方法是，扩展BaseAdapter 并实现SpinnerAdapter以创建您自己的适配器，它知道您的ArrayList中的元素是对象以及如何使用这些对象的属性。
[修改]实现示例
我玩了一会儿，我设法得到了一些工作：
public class Main extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Create and display a Spinner:
Spinner s = new Spinner(this);
AbsListView.LayoutParams params = new AbsListView.LayoutParams(
ViewGroup.LayoutParams.FILL_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT
);
this.setContentView(s, params);
// fill the ArrayList:
List<Guy> guys = new ArrayList<Guy>();
guys.add(new Guy("Lukas", 18));
guys.add(new Guy("Steve", 20));
guys.add(new Guy("Forest", 50));
MyAdapter adapter = new MyAdapter(guys);
// apply the Adapter:
s.setAdapter(adapter);
// onClickListener:
s.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
/**
* Called when a new item was selected (in the Spinner)
*/
public void onItemSelected(AdapterView<?> parent,
View view, int pos, long id) {
Guy g = (Guy) parent.getItemAtPosition(pos);
Toast.makeText(
getApplicationContext(),
g.getName()+" is "+g.getAge()+" years old.",
Toast.LENGTH_LONG
).show();
}
public void onNothingSelected(AdapterView parent) {
// Do nothing.
}
});
}
/**
* This is your own Adapter implementation which displays
* the ArrayList of "Guy"-Objects.
*/
private class MyAdapter extends BaseAdapter implements SpinnerAdapter {
/**
* The internal data (the ArrayList with the Objects).
*/
private final List<Guy> data;
public MyAdapter(List<Guy> data){
this.data = data;
}
/**
* Returns the Size of the ArrayList
*/
@Override
public int getCount() {
return data.size();
}
/**
* Returns one Element of the ArrayList
* at the specified position.
*/
@Override
public Object getItem(int position) {
return data.get(position);
}
@Override
public long getItemId(int i) {
return i;
}
/**
* Returns the View that is shown when a element was
* selected.
*/
@Override
public View getView(int position, View recycle, ViewGroup parent) {
TextView text;
if (recycle != null){
// Re-use the recycled view here!
text = (TextView) recycle;
} else {
// No recycled view, inflate the "original" from the platform:
text = (TextView) getLayoutInflater().inflate(
android.R.layout.simple_dropdown_item_1line, parent, false
);
}
text.setTextColor(Color.BLACK);
text.setText(data.get(position).name);
return text;
}
}
/**
* A simple class which holds some information-fields
* about some Guys.
*/
private class Guy{
private final String name;
private final int age;
public Guy(String name, int age){
this.name = name;
this.age = age;
}
public String getName() {
return name;
}
public int getAge() {
return age;
}
}
}
我对代码进行了完整的注释，如果您有任何问题，请不要犹豫。