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Android 即使退出应用程序,如何保留从微调器中选择的项目?_Android_Sharedpreferences_Android Sharedpreferences - Fatal编程技术网

Android 即使退出应用程序,如何保留从微调器中选择的项目?

Android 即使退出应用程序,如何保留从微调器中选择的项目?,android,sharedpreferences,android-sharedpreferences,Android,Sharedpreferences,Android Sharedpreferences,下面是我的代码,它在单击时从微调器获取项目 public class SpinnerActivity extends AppCompatActivity implements AdapterView.OnItemSelectedListener { private Spinner spinner1,spinner2,spinner3; private static final String[] sports = { "Hockey","Cricket","Football","

下面是我的代码,它在单击时从微调器获取项目

public class SpinnerActivity extends AppCompatActivity implements AdapterView.OnItemSelectedListener {

private Spinner spinner1,spinner2,spinner3;
private static final String[] sports = {
        "Hockey","Cricket","Football","Basketball","Badminton","Tennis"
};

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

    spinner1 = (Spinner)findViewById(R.id.drop_down);
    spinner2 = (Spinner)findViewById(R.id.drop_down2);
    spinner3 = (Spinner)findViewById(R.id.drop_down3);
    ArrayAdapter<String> adapter;
    adapter = new ArrayAdapter<String>(this,
            android.R.layout.simple_spinner_item,sports);

    adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    spinner1.setAdapter(adapter);
    spinner2.setAdapter(adapter);
    spinner3.setAdapter(adapter);
}

@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
    String item = parent.getItemAtPosition(position).toString();
}

@Override
public void onNothingSelected(AdapterView<?> parent) {
}
}
公共类SpinneActivity扩展AppCompativity实现AdapterView.OnItemSelectedListener{
专用喷丝头1、喷丝头2、喷丝头3;
私有静态最终字符串[]运动={
曲棍球、板球、足球、篮球、羽毛球、网球
};
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity\u微调器);
喷丝头1=(喷丝头)findViewById(R.id.drop\u down);
喷丝头2=(喷丝头)findViewById(R.id.drop\U down2);
喷丝头3=(喷丝头)findViewById(R.id.drop\U down3);
阵列适配器;
适配器=新阵列适配器(此,
android.R.layout.simple_spinner_项目,运动);
setDropDownViewResource(android.R.layout.simple\u微调器\u下拉菜单\u项);
喷丝头1.设置适配器(适配器);
喷丝头2.设置适配器(适配器);
喷丝头3.设置适配器(适配器);
}
@凌驾
已选择公共视图(AdapterView父视图、视图视图、整型位置、长id){
String item=parent.getItemAtPosition(position.toString();
}
@凌驾
未选择公共无效(AdapterView父级){
}
}

如何在退出应用程序后保留选定微调器的项目?

您可以使用
SharedReference
存储选定的值位置/id/string

当您获得字符串项时,只需添加此行

Editor edit = context.getSharedPreferences("Name_of_sf",Context.MODE_PRIVATE).edit();
edit.putString("selected_item", item);
edit.commit();
并且可以简单地检索值作为

context.getSharedPreferences("Name_of_sf",Context.MODE_PRIVATE).getString("selected_item", "");

有关更多信息@AnirudhSohil,您可以查看官方文档,其中有非常详细的示例,希望对您有所帮助


使用
SharedReference
。如何在其中使用SharedReference?