我有一堂这样的课:
public class CountryVO {
private String countryCode;
private String countryName;
private Drawable countryFlag;
public String getCountryCode() {
return countryCode;
}
public void setCountryCode(String countryCode) {
this.countryCode = countryCode;
}
public String getCountryName() {
return countryName;
}
public void setCountryName(String countryName) {
this.countryName = countryName;
}
public Drawable getCountryFlag() {
return countryFlag;
}
public void setCountryFlag(Drawable countryFlag) {
this.countryFlag = countryFlag;
}
}
我想将此类的对象存储在Android的
TypeArray
XML中,如下所示:
<resources>
<array name="custom_arr">
<item>
<countryName>Albania</countryName>
<countryCode>al</countryCode>
<countryFlag>@drawable/al</countryFlag>
</item>
<item>
<countryName>Algeria</countryName>
<countryCode>dz</countryCode>
<countryFlag>@drawable/dz</countryFlag>
</item>
<item>
<countryName>American Samoa</countryName>
<countryCode>as</countryCode>
<countryFlag>@drawable/as</countryFlag>
</item>
<item>
<countryName>India</countryName>
<countryCode>in</countryCode>
<countryFlag>@drawable/in</countryFlag>
</item>
<item>
<countryName>South Africa</countryName>
<countryCode>sa</countryCode>
<countryFlag>@drawable/sa</countryFlag>
</item>
</array>
</resources>
这就是我想在我的
Activty
类中访问此数组的方式:
TypedArray customArr = getResources().obtainTypedArray(R.array.country_arr);
CountryVO vo = new CountryVO();
vo.setCountryName(**value from array come here for first element's countryName attribute**);
vo.setCountryCode(**value from array come here for first element's countryCode attribute**);
vo.setCountryFlag(**value from array come here for first element's countryFlag attribute**);
但我不知道如何实现这一目标。
我尝试了
customArr.getString(0);
,但它给了我一切作为字符串,如“Albania al @drawable/al”
请帮我解决这个问题。
这是示例。阅读它并查看 TypedArray 的方法,例如
get...()
,例如 getDrawable(int index)
。我建议将相同类型的项目保留在单独的数组中。
<array name="country">
<item>Albania</item>
<item>Algeria</item>
<item>American Samoa</item>
</array>
<array name="code">
<item>al</item>
<item>dz</item>
<item>as</item>
</array>
<array name="flag">
<item>@drawable/dz</item>
<item>@drawable/al</item>
<item>@drawable/as</item>
</array>
编辑:
public CountryVO getCountryVO(int index){
Resources resources = getResources();
TypedArray country = resources.obtainTypedArray(R.array.country);
TypedArray code = resources.obtainTypedArray(R.array.code);
TypedArray flag = resources.obtainTypedArray(R.array.flag);
CountryVO vo = new CountryVO(country.getString(index), code.getString(index), flag.getDrawable(index));
country.recycle();
code.recycle();
flag.recycle();
return vo;
}
当我需要可以在代码外部编辑的自定义对象时,我通常使用 json,它对于人类和(可能)机器来说都更容易阅读;)
您还可以拥有比简单数组更复杂的对象。
在
/res/raw
文件夹中创建一个json文件(例如country.json),如下所示:
{ "countries" : [
{"country" : "Albania", "countryCode" : "al" },
{"country" : "Algeria", "countryCode" : "dz"},
{"country" : "American Samoa", "countryCode" : "as"},
{"country" : "India", "countryCode" : "in"},
{"country" : "South Africa", "countryCode" : "sa"}
]}
您可以像这样加载数据:
InputStream jsonStream = context.getResources().openRawResource(R.raw.countries);
JSONObject jsonObject = new JSONObject(Strings.convertStreamToString(jsonStream));
JSONArray jsonContries = jsonObject.getJSONArray("countries");
List<CountryVO> countries = new ArrayList<CountryVO>();
for (int i = 0, m = countries.length(); i < m; i++) {
JSONObject jsonCountry = countries.getJSONObject(i);
CountryVO country = new CountryVO();
country.setCountryName(jsonCountry.getString("country"));
String co = jsonCountry.getString("countryCode");
country.setCountryCode(co);
try {
Class<?> drawableClass = com.example.R.drawable.class; // replace package
Field drawableField = drawableClass.getField(co);
int drawableId = (Integer)drawableField.get(null);
Drawable drawable = getResources().getDrawable(drawableId);
country.setCountryFlag(drawable);
} catch (Exception e) {
// report exception
}
countries.add(country);
}
如果您不想手动进行解析,您还可以使用 gson 它可以帮助您传递对象,然后以惰性方式加载可绘制对象...;)
编辑:添加实用程序类
public String convertStreamToString(InputStream is) {
Scanner s = new Scanner(is).useDelimiter("\\A");
return s.hasNext() ? s.next() : "";
}
希望有帮助
您需要先解析 xml,然后再尝试将其存储到您的类中。我建议您使用 SAX API,您可以在这里找到有关它的教程。希望这会有所帮助!