Question

您好我是android，java的新手，我想使用来自另一个类的方法的字符串。具体来说，我想使用String来从类Test到类MainActivity。我试着称之为

Test.AnswerQ1

但它表示无法解析符号＆＃34; AnswerQ1＆＃34;
这是我的测试类

public class Test extends Activity {




 private RadioGroup radioGroupQuestion1;
 private RadioButton radioButtonQuestion1;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

   radioGroupQuestion1 = (RadioGroup) findViewById(R.id.radioGroupQ1);


   Button NextButton = (Button) findViewById(R.id.Q1NextButton);
    NextButton.setOnClickListener(new View.OnClickListener() {
        public void onClick(View view) {

           int selectedId =  radioGroupQuestion1.getCheckedRadioButtonId();
            radioButtonQuestion1 = (RadioButton) findViewById(selectedId);
            String AnswerQ1 = radioButtonQuestion1.getText().toString();
            String Question1 = getString(R.string.Q1);
            System.out.println(Question1);

           System.out.println(AnswerQ1);

           Intent myIntent = new Intent(view.getContext(),  Question2.class);
            startActivityForResult(myIntent, 0);
        }
    });
}

这是我的MainActivity类

public class MainActivity extends Activity{

String myData = Test.s;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

   System.out.println(myData);   

   } 
}

Answer 1

Try with initializing string on the top of an onCreate method. 

public class Test extends Activity {

public static String s = "hello world";

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

   }
}

Answer 2

不要在实例方法中声明静态成员。

您必须将静态成员声明为类成员而非本地成员。

示例：

// This function will run inside of a web-page, not in the CasperJS script
function putInObject() {
     var obj = {}; // UPDATED: here we also need to init this object
     obj.title = document.querySelector('[itemprop="title"]').innerText;
     obj.description = document.querySelector('[itemprop="description"]').innerText;

     // return data from a web page context to CasperJS context
     return obj;
}

...

     // receive data in CasperJS context
     obj = casper.evaluate(putInObject);

     // If you want to view object's contents
     console.log(JSON.stringify(obj));

Answer 3

你可以制作s public static但是还有很多其他解决方案。根据您的需要，您可以使用Shared Preference，Broadcast Listener，Interface等。

如何从另一个Android类的方法调用字符串

3 个答案: