Question

在我的项目中。有三个文件。

passParaActivity.java 
//main Activity, show a edittext and a button to reslut.java
result.java 
//display the number which typed in passParaAcitivity.java
mainFunc.java 
//function to get the number from passParaActivity.java

这是与passParaActivity.java相关的main.xml。

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >
   <TextView android:layout_width="fill_parent"
             android:layout_height="wrap_content"
             android:text="Type a number:"
             android:textSize="20dp"/>
   <EditText android:layout_width="fill_parent"
             android:layout_height="wrap_content"
             android:hint="Type a number"
             android:id="@+id/number"/>
   <Button android:layout_width="fill_parent"
           android:layout_height="wrap_content"
           android:text="PASS"
           android:id="@+id/btn"/>
</LinearLayout>

这是result.xml的代码。

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <TextView android:layout_width="fill_parent"
              android:layout_height="wrap_content"
              android:text="The number is:"
              android:textSize="20dp"/>
    <TextView android:layout_width="fill_parent"
              android:layout_height="wrap_content"
              android:textSize="30dp"
              android:textColor="#0000ff"
              android:id="@+id/mytext"/>
    <Button android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:text="Back"
            android:id="@+id/back"/>

</LinearLayout>

passParaActivity.java：

 public Button btn;
    public EditText number;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        btn = (Button) findViewById(R.id.btn);
        number = (EditText) findViewById(R.id.number);

        btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                Intent intent = new Intent(PassParaActivity.this, result.class);
                startActivity(intent);
            }
        });
    }

result.java：

public TextView mytext;
    public Button back;
    mainFunc main;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.result);
        mytext = (TextView) findViewById(R.id.mytext);
        back = (Button) findViewById(R.id.back);

        main = new mainFunc(result.this);
        mytext.setText(main.getNum());

        back.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                Intent intent = new Intent(result.this, PassParaActivity.class);
                startActivity(intent);
            }
        });
    }

mainFunc.java

public class mainFunc {
    private PassParaActivity mycontext;
    int num = 0;
    public mainFunc(Context context){
        mycontext = (PassParaActivity) context;
    }

    public int getNum(){
        num = Integer.parseInt(mycontext.number.getText().toString());
        return num;
    }
}

我怎样才能使这个工作？谢谢你的病人。

Answer 1

如果您询问如何将数据从一个活动传递到另一个活动，您可以使用Intent extras：

intent.putExtra("Number", "Value");

请参阅：How to start an Intent by passing some parameters to it?

Answer 2

您也可以尝试使用“共享首选项”来存储值。

  SharedPreferences prefs = PreferenceManager
 .getDefaultSharedPreferences(this.getApplicationContext());
  Editor prefsEditor = prefs.edit();
  prefsEditor.putString("key","value");
  prefsEditor.commit();

并重新审视

  SharedPreferences prefs = PreferenceManager
 .getDefaultSharedPreferences(this.getApplicationContext());
 String value = prefs.getString("key","defaultValue");

Android问题：如何从edittext获取内容

2 个答案: