如何使用保存的istance状态和Android的恢复与纺纱实例的状态？ [英] How to use saved istance state and restore instance state with spinners in in Android?
问题描述
我在我的活性，使其具有一个选项列表，
I have a spinner in my activity with a list of options,
当用户选择一个选项，我用OnItemSelected适配器获得所选选项的位置值和内我增加了一些如else语句。如果语句，竟产生从TextView中的predefined数据库并显示一个随机字符串。
When the user selects an option, I have used OnItemSelected adapter to get the position value of the selected option and within that i have added some If Else Statements. The If statement, actually generates a random string from the predefined database and displays on TextView.
现在我将切换回另一个活动，并再次回到这个活动。现在的问题是默认微调的第一个选项是唯一入选的，我需要的用户最后选择的选项，当活动再次启动该选项的功能，必须运行更新。
Now i will be switching back to another activity and again come back to this activity. Now the problem is by default the first option of the spinner is only selected, I need to update with the last selected option of the user and when the activity starts again that option's functions must be run.
我做了一些搜索过，发现这可以通过使用的onSaveInstanceState 和 onRestoreInstanceState 现在已经完成了：
I did some searches too and found that this can be done by using onSaveInstanceState and onRestoreInstanceState now :
- 如何使用这两个，我应该在这里把他们的onItemSelected（适配器）或外部？ 里面
- 如何更新（或存储）由用户选择的随机生成的code？ 新的位置值
- How do I use these two and where should i put them, inside the onItemSelected(adapter) or Outside?
- How do I update(or store) the new position value selected by the user to the random generated code?
为了清楚起见，请查看我的code：
For clarity please check my code:
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layout_scheduledactivity);
/**displayed when the activity is launched (this should be
updated with the user selected option)**/
Resources res = getResources();
myString = res.getStringArray(R.array.normal);
String q = myString[rgenerator.nextInt(myString.length)];
TextView tv = (TextView) findViewById(R.id.text1);
tv.setText(q);
//initiating the spinner
Spinner s = (Spinner) findViewById( R.id.spinner);
s.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener(){
@Override
public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) {
if (pos == 1){
//displayed on the time when user selects the option
Resources res = getResources();
myString = res.getStringArray(R.array.hardships);
String q = myString[rgenerator.nextInt(myString.length)];
TextView tv = (TextView) findViewById(R.id.text1);
tv.setText(q);
}
else {
//do nothing
}
EDITED问题：
我已经编辑更加清晰的问题。基本上我所要做的是，我要救他们由用户选择的位置，以微调。当用户点击三江源按钮活动将完成，并通过不同的类广播接收器叫做几分钟后就会开始。当活动再次开始用户的最后一个所选选项（previous活动）必须为默认在此活动
I have edited the question for more clarity. Basically what I am trying to do is, I want to save the position selected by they user, with the spinner. When the user clicks "Thankyou" Button the activity will finish and will start after few minutes called by a Broadcast receiver from a different class. When the activity starts again the last selected option (previous activity) of the user must be as default in this activity.
我想，如果你看一下code中的问题在保存和恢复实例状态。请您能有所帮助。先谢谢了。
I think if you look at the code the problem is in save and restore instance state. Please can you help. Thanks in advance.
请看看我的code：
import java.util.Random;
import android.app.Activity;
import android.content.res.Resources;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;
public class MyScheduledActivity extends Activity {
private String[] myString;
private static final Random rgenerator = new Random();
protected int mPos;
protected String mSelection;
String situation[] = {"Normal","Hardship","Sadness","Exam"};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layout_scheduledactivity);
if (mPos == 0) {
Resources res = getResources();
myString = res.getStringArray(R.array.normal);
String q = myString[rgenerator.nextInt(myString.length)];
TextView tv = (TextView) findViewById(R.id.text1);
tv.setText(q);
}
//selection of the spinner
Spinner s = (Spinner) findViewById( R.id.spinner);
// Application of the Array to the Spinner
ArrayAdapter<String> spinnerArrayAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, situation);
spinnerArrayAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
s.setAdapter(spinnerArrayAdapter);
s.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener(){
@Override
public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) {
MyScheduledActivity.this.mPos = pos;
MyScheduledActivity.this.mSelection = parent.getItemAtPosition(pos).toString();
//display toast
Toast.makeText(parent.getContext(), "The Situation is " +
parent.getItemAtPosition(pos).toString(), Toast.LENGTH_LONG).show();
if (mPos == 0){
Resources res = getResources();
myString = res.getStringArray(R.array.hardships);
String q = myString[rgenerator.nextInt(myString.length)];
TextView tv = (TextView) findViewById(R.id.text1);
tv.setText(q);
}
if (mPos == 1){
Resources res = getResources();
myString = res.getStringArray(R.array.hardships);
String q = myString[rgenerator.nextInt(myString.length)];
TextView tv = (TextView) findViewById(R.id.text1);
tv.setText(q);
}
else {
//do nothing
}
}
@Override
public void onNothingSelected(AdapterView<?> parentView) {
//do something else
return;
}
});
//dismiss button - Thank You
Button buttonDismiss = (Button)findViewById(R.id.dismiss);
buttonDismiss.setOnClickListener(new Button.OnClickListener(){
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
finish();
}});
}
@Override
protected void onSaveInstanceState(Bundle outState) {
outState.putStringArray(mSelection, situation);
super.onSaveInstanceState(outState);
}
@Override
protected void onRestoreInstanceState(Bundle savedInstanceState) {
situation = savedInstanceState.getStringArray("mSelection");
super.onRestoreInstanceState(savedInstanceState);
}
}
推荐答案
在您的present活动覆盖了一个名为方法的onSaveInstanceState（），把你的数据包
In your present Activity override a method called onSaveInstanceState() and put your data in bundle.
和覆盖另一种方法 onRestoreInstanceState（），并从包获取这些值....
and override another method onRestoreInstanceState() and get those values from the bundle....
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