Java 动态设置微调器非持续状态
我正在开发一个简单的应用程序,遇到了一个动态创建的Java 动态设置微调器非持续状态,java,android,Java,Android,我正在开发一个简单的应用程序,遇到了一个动态创建的微调器的状态持久化问题。无论我为动态微调器选择什么,它总是重置为定义的第一个元素。我已经覆盖了onPause和onResume,但没有任何效果。任何帮助都会很好 public class MainActivity extends Activity { private OnItemSelectedListener optionListener = getOptionListener(); // private OnItemSelectedList
微调器
的状态持久化问题。无论我为动态微调器选择什么,它总是重置为定义的第一个元素。我已经覆盖了onPause
和onResume
,但没有任何效果。任何帮助都会很好
public class MainActivity extends Activity {
private OnItemSelectedListener optionListener = getOptionListener();
// private OnItemSelectedListener specificListener;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
((Spinner)findViewById(R.id.optionsSpinner)).setOnItemSelectedListener(optionListener);
}
@Override
public void onPause()
{
super.onPause();
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
int generalIndex = ((Spinner)findViewById(R.id.optionsSpinner)).getSelectedItemPosition();
int specificIndex = ((Spinner)findViewById(R.id.specificOptions)).getSelectedItemPosition();
prefs.edit().putInt("general", generalIndex).putInt("specific", specificIndex).commit();
}
@Override
public void onResume()
{
super.onResume();
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
int generalIndex = prefs.getInt("general", -1);
int specificIndex = prefs.getInt("specific", -1);
((Spinner)findViewById(R.id.optionsSpinner)).setSelection(generalIndex);
((Spinner)findViewById(R.id.specificOptions)).setSelection(specificIndex);
}
private OnItemSelectedListener getOptionListener()
{
return new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View v, int pos, long id) {
int resId;
String selectedOption = parent.getSelectedItem().toString();
if (selectedOption.equals(getString(R.string.color)))
resId = R.array.colorsArray;
else
resId = R.array.shapesArray;
ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(getBaseContext(), resId, android.R.layout.simple_spinner_item);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
((Spinner)findViewById(R.id.specificOptions)).setAdapter(adapter);
}
@Override
public void onNothingSelected(AdapterView<?> arg0) { }
};
}
公共类MainActivity扩展活动{
private OnItemSelectedListener optionListener=getOptionListener();
//private OnItemSelectedListener specificListener;
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
((微调器)findViewById(R.id.optionsSpinner)).setOnItemSelectedListener(optionListener);
}
@凌驾
公共无效暂停()
{
super.onPause();
SharedReferences prefs=PreferenceManager.GetDefaultSharedReferences(getApplicationContext());
int-generandex=((微调器)findViewById(R.id.optionsSpinner)).getSelectedItemPosition();
int specificIndex=((微调器)findViewById(R.id.specificOptions)).getSelectedItemPosition();
prefs.edit().putin(“常规”,generalIndex).putin(“特定”,specificIndex).commit();
}
@凌驾
恢复时公开作废()
{
super.onResume();
SharedReferences prefs=PreferenceManager.GetDefaultSharedReferences(getApplicationContext());
int-generalIndex=prefs.getInt(“general”,-1);
int specific index=prefs.getInt(“specific”,-1);
((微调器)findViewById(R.id.optionsSpinner)).setSelection(generalIndex);
((微调器)findViewById(R.id.specificOptions)).setSelection(specificIndex);
}
private OnItemSelectedListener getOptionListener()
{
返回新的MSelectedListener(){
@凌驾
已选择公共位置(AdapterView父项、视图v、内部位置、长id){
国际剩余;
String selectedOption=parent.getSelectedItem().toString();
if(selectedOption.equals(getString(R.string.color)))
resId=R.array.colorsArray;
其他的
resId=R.array.shapesArray;
ArrayAdapter=ArrayAdapter.createFromResource(getBaseContext(),resId,android.R.layout.simple\u微调器\u项);
setDropDownViewResource(android.R.layout.simple\u微调器\u下拉菜单\u项);
((微调器)findViewById(R.id.specificOptions)).setAdapter(适配器);
}
@凌驾
未选择的公共无效(AdapterView arg0){}
};
}
首先,首选项编辑器有问题。您需要提交以下首选项:
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
int generalIndex = ((Spinner)findViewById(R.id.optionsSpinner)).getSelectedItemPosition();
int specificIndex = ((Spinner)findViewById(R.id.specificOptions)).getSelectedItemPosition();
Editor editor = prefs.edit();
editor.putInt("general", generalIndex);
editor.putInt("specific", specificIndex);
editor.commit();
否则,将不会保存您的首选项
我想指出的另一件事是,您需要避免将-1
作为默认首选项值,然后将-1
与.setSelection(value);
一起使用,这将导致您出现异常。如果返回-1,请避免任何选择。了解了该怎么做:
1) .提供两个私有变量(一个用于特定索引,一个用于一般索引)
2) .设置共享首选项中的两个变量
3) 。在onItemSelectedListener中,设置特定选项微调器
public class MainActivity extends Activity {
private int specificIndex;
private int generalIndex;
private OnItemSelectedListener optionListener = getOptionListener();
// private OnItemSelectedListener specificListener;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
((Spinner)findViewById(R.id.optionsSpinner)).setOnItemSelectedListener(optionListener);
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
// Initial setup
generalIndex = prefs.getInt("general", 0);
specificIndex = prefs.getInt("specific", 0);
}
@Override
public void onPause()
{
super.onPause();
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
generalIndex = ((Spinner)findViewById(R.id.optionsSpinner)).getSelectedItemPosition();
specificIndex = ((Spinner)findViewById(R.id.specificOptions)).getSelectedItemPosition();
prefs.edit().putInt("general", generalIndex).putInt("specific", specificIndex).commit();
}
@Override
public void onResume()
{
super.onResume();
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
generalIndex = prefs.getInt("general", 0);
specificIndex = prefs.getInt("specific", 0);
}
private OnItemSelectedListener getOptionListener()
{
return new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View v, int pos, long id) {
int resId;
String selectedOption = parent.getSelectedItem().toString();
if (selectedOption.equals(getString(R.string.color)))
resId = R.array.colorsArray;
else
resId = R.array.shapesArray;
ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(getBaseContext(), resId, android.R.layout.simple_spinner_item);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
((Spinner)findViewById(R.id.specificOptions)).setAdapter(adapter);
if (specificIndex != 0)
((Spinner)findViewById(R.id.specificOptions)).setSelection(specificIndex);
}
@Override
public void onNothingSelected(AdapterView<?> arg0) { }
};
}
公共类MainActivity扩展活动{
私有索引;
私人综合指数;
private OnItemSelectedListener optionListener=getOptionListener();
//private OnItemSelectedListener specificListener;
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
((微调器)findViewById(R.id.optionsSpinner)).setOnItemSelectedListener(optionListener);
SharedReferences prefs=PreferenceManager.GetDefaultSharedReferences(getApplicationContext());
//初始设置
generalIndex=prefs.getInt(“一般”,0);
specificIndex=prefs.getInt(“specific”,0);
}
@凌驾
公共无效暂停()
{
super.onPause();
SharedReferences prefs=PreferenceManager.GetDefaultSharedReferences(getApplicationContext());
generalIndex=((微调器)findViewById(R.id.options微调器)).getSelectedItemPosition();
specificIndex=((微调器)findViewById(R.id.specificOptions)).getSelectedItemPosition();
prefs.edit().putin(“常规”,generalIndex).putin(“特定”,specificIndex).commit();
}
@凌驾
恢复时公开作废()
{
super.onResume();
SharedReferences prefs=PreferenceManager.GetDefaultSharedReferences(getApplicationContext());
generalIndex=prefs.getInt(“一般”,0);
specificIndex=prefs.getInt(“specific”,0);
}
private OnItemSelectedListener getOptionListener()
{
返回新的MSelectedListener(){
@凌驾
已选择公共位置(AdapterView父项、视图v、内部位置、长id){
国际剩余;
String selectedOption=parent.getSelectedItem().toString();
if(selectedOption.equals(getString(R.string.color)))
resId=R.array.colorsArray;
其他的
resId=R.array.shapesArray;
ArrayAdapter=ArrayAdapter.createFromResource(getBaseContext(),resId,android.R.layout.simple\u微调器\u项);
setDropDownViewResource(android.R.layout.simple\u微调器\u下拉菜单\u项);
((微调器)findViewById(R.id.specificOptions)).setAdapter(适配器);
如果(specificIndex!=0)
((微调器)findViewById(R.id.specificOptions)).setSelection(specificIndex);
}
@凌驾
未选择的公共无效(AdapterView arg0){}
};
}
}我理解-1位,但它只是为了演示。它实际上从来没有给我-1。关于共享引用的主题,如果你看一下onPause,我会提交首选项:prefs.edit().putin(“general”,generalIndex)。putin(“specific”,specificIndex)。commit();