我有一个进行异步调用的片段，分配给一个对象变量（这花了我一段时间才弄明白），然后点击一个按钮，它通过适配器将cardviews加载到屏幕上。
我使用的代码是：
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, final Bundle savedInstanceState) {
super.onCreateView(inflater, container, savedInstanceState);
View view = inflater.inflate(R.layout.fragments_stops_list, container, false);
ButterKnife.bind(this, view); // since this is a fragment the butterknife bind method should goafter the view declaration
// saved state would indicate that we are now not capable of making multiple requests. This point has been
// properly taken care of and now I can purposely move on to other things of more importance
loadButton = (Button) view.findViewById(R.id.LOAD);
if(savedInstanceState == null) {
loadButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Log.d(">==========<", extractCreate.getCreateR().getPhone());
Parcelable[] parcelable = extractCreate.getStopsR();
commodities = Arrays.copyOf(parcelable, parcelable.length, Stops[].class);
//Log.d("Commodities size check", String.valueOf(commodities.length));
StopsAdapter adapter = new StopsAdapter(commodities);
mRecyclerView.setAdapter(adapter);
RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(getActivity()); // sketchy on this part
mRecyclerView.setLayoutManager(layoutManager);
mRecyclerView.setHasFixedSize(true);
Log.d(TAG, "This is being called from the onCreate method");
}
});
}
return view;
}
问题是，如果我尝试旋转屏幕然后内容消失并再次出现，则必须单击按钮（id.LOAD），我添加了一个语句来检查saveInstance状态是否为null，当我转动屏幕时，我通过适配器加载的cardviews消失并且无法再次加载它时，该解决方案不能正常工作。
onViewStateRestored方法的内容，但这个想法看起来并不乐观，因为内容需要在点击监听器内处理。
任何建议都将不胜感激。
根据要求，这是。
的代码public class Stops implements Parcelable{
private String stop_id;
private String type;
private String location;
private String address;
private String city;
private String state;
private String zip;
private String from;
private String to;
private String getitem;
private Commodities[] commodities;
public Stops() {}
public String getStop_id() {
return stop_id;
}
public void setStop_id(String stop_id) {
this.stop_id = stop_id;
}
public String getType() {
return type;
}
public void setType(String type) {
this.type = type;
}
public String getLocation() {
return location;
}
public void setLocation(String location) {
this.location = location;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
public String getState() {
return state;
}
public void setState(String state) {
this.state = state;
}
public String getZip() {
return zip;
}
public void setZip(String zip) {
this.zip = zip;
}
public String getFrom() {
return from;
}
public void setFrom(String from) {
this.from = from;
}
public String getTo() {
return to;
}
public void setTo(String to) {
this.to = to;
}
public Commodities[] getCommodities() {
return commodities;
}
public void setCommodities(Commodities[] commodities) {
this.commodities = commodities;
}
/**
* The content for the actual parcelables start in here
*
* */
@Override
public int describeContents() {
return 0;
}
@Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeString(this.stop_id);
dest.writeString(this.type);
dest.writeString(this.location);
dest.writeString(this.address);
dest.writeString(this.city);
dest.writeString(this.state);
dest.writeString(this.zip);
dest.writeString(this.from);
dest.writeString(this.to);
dest.writeString(this.getitem);
dest.writeTypedArray(this.commodities, flags);
}
protected Stops(Parcel in) {
this.stop_id = in.readString();
this.type = in.readString();
this.location = in.readString();
this.address = in.readString();
this.city = in.readString();
this.state = in.readString();
this.zip = in.readString();
this.from = in.readString();
this.to = in.readString();
this.getitem = in.readString();
this.commodities = in.createTypedArray(Commodities.CREATOR);
}
public static final Parcelable.Creator<Stops> CREATOR = new Parcelable.Creator<Stops>() {
@Override
public Stops createFromParcel(Parcel source) {
return new Stops(source);
}
@Override
public Stops[] newArray(int size) {
return new Stops[size];
}
};
}
答案 0 :(得分：3)
由于您的片段在更改方向时被销毁并再次创建，因此您必须实现一些逻辑，以便保存在方向更改事件之前收集的数据。
这是通过覆盖 onSavedInstanceState（Bundle bundle）方法完成的。您需要保存的所有内容都包含在此处。您将数据放入 Bundle 对象并为其分配密钥，以便最近能够检索它。
当操作系统再次重新创建片段时，它将再次通过 onCreateView（）方法。您必须在此处检查 savedInstanceState 对象是否为NULL。如果不是，那么它很可能包含一些在方向更改事件发生之前保存的数据。
查看以下要点。
public class SomeClass extends Activity {
private static final String KEY = "some_key";
commodities;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, final Bundle savedInstanceState) {
super.onCreateView(inflater, container, savedInstanceState);
View view = inflater.inflate(R.layout.fragments_stops_list, container, false);
ButterKnife.bind(this, view); // since this is a fragment the butterknife bind method should goafter the view declaration
// saved state would indicate that we are now not capable of making multiple requests. This point has been
// properly taken care of and now I can purposely move on to other things of more importance
loadButton = (Button) view.findViewById(R.id.LOAD);
if(savedInstanceState == null) {
loadButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Log.d(">==========<", extractCreate.getCreateR().getPhone());
Parcelable[] parcelable = extractCreate.getStopsR();
commodities = Arrays.copyOf(parcelable, parcelable.length, Stops[].class);
//Log.d("Commodities size check", String.valueOf(commodities.length));
StopsAdapter adapter = new StopsAdapter(commodities);
mRecyclerView.setAdapter(adapter);
RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(getActivity()); // sketchy on this part
mRecyclerView.setLayoutManager(layoutManager);
mRecyclerView.setHasFixedSize(true);
Log.d(TAG, "This is being called from the onCreate method");
}
});
} else {
if(savedInstanceState.containsKey(KEY)) {
commodities = savedInstanceState.getParcelable(KEY);
// here you will pretty much repete the code from above
// for creating an Adapter for the RecyclerView
StopsAdapter adapter = new StopsAdapter(commodities);
mRecyclerView.setAdapter(adapter);
RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(getActivity()); // sketchy on this part
mRecyclerView.setLayoutManager(layoutManager);
mRecyclerView.setHasFixedSize(true);
}
}
return view;
}
@Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putParcelable(KEY, commodities);
}
}
为了正确保存您的数据，您的商品类需要实现Parcelable。请查看此链接以获取更多信息。 Parcelable
P.S。 由于我不知道你的商品对象的实际类型，你将不得不修改一下代码。只是一个简单的副本 - ＆gt;粘贴不起作用！
答案 1 :(得分：0)
将它放在Manifest的Activity标签
中 android:configChanges="orientation|keyboardHidden|screenSize"
希望这会有所帮助。