我正在尝试实现多个片段。当我单击底部导航按钮时，每个片段都在一个更改或替换的活动中查看。能够将数据从 frag1 传递到 frag2，但是如果我单击 frag2 或任何其他片段按钮导航栏，即此处的流栏，它将被重置并且数据丢失。
这是我自己尝试过的：我在第二个片段中实现了 onSaveInstanceState，但是没有用。不知何故，片段正在新创建。
还尝试了这里提到的解决方案
这里只是一个想法是布局
主要活动
import android.graphics.drawable.Drawable;
import android.os.Build;
import android.support.annotation.NonNull;
import android.support.design.widget.BottomNavigationView;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.MenuItem;
import android.view.View;
import android.widget.TextView;
import com.br.tron.bottombar.RadioFragment;
import com.br.tron.bottombar.StreamFragment;
import com.br.tron.bottombar.InfoFragment;
public class MainActivity extends AppCompatActivity implements PushStreamLink{
BottomNavigationView bottomNavigationView;
private Fragment fragment;
private FragmentManager fragmentManager;
View view;
//private FragmentTransaction transaction;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
fragmentManager = getSupportFragmentManager();
fragment = new RadioFragment();
fragment.setRetainInstance(true);
FragmentTransaction transaction = fragmentManager.beginTransaction();
transaction.replace(R.id.main_container, fragment).commit();
bottomNavigationView = (BottomNavigationView) findViewById(R.id.bottomNavigationBar);
bottomNavigationView.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener(){
@Override
public boolean onNavigationItemSelected(@NonNull MenuItem item) {
String tag = "";
switch (item.getItemId()) {
case R.id.nav_button_one:
fragment = new RadioFragment();
fragment.setRetainInstance(true);
tag = "radio_fragment";
break;
case R.id.nav_button_two:
fragment = new StreamFragment();
fragment.setRetainInstance(true);
tag = "stream_fragment";
break;
case R.id.nav_button_three:
fragment = new InfoFragment();
fragment.setRetainInstance(true);
tag = "info_fragment";
break;
}
FragmentTransaction transaction = fragmentManager.beginTransaction();
transaction.replace(R.id.main_container, fragment, tag).commit();
return true;
}
});
}
@Override
public void sendStreamLink(String link) {
fragment =new StreamFragment();
fragment.setRetainInstance(true);
fragmentManager=getSupportFragmentManager();
FragmentTransaction transaction = fragmentManager.beginTransaction();
transaction.replace(R.id.main_container, fragment,"stream_fragment").addToBackStack(null).commit();
getSupportFragmentManager().executePendingTransactions();
StreamFragment sf=(StreamFragment) getSupportFragmentManager().findFragmentByTag("stream_fragment");
sf.getUrl(link);
view = bottomNavigationView.findViewById(R.id.nav_button_two);
view.performClick();
}
}
RadioFragment（我从中发送数据的片段）
import android.app.Activity;
import android.content.Context;
import android.support.v4.app.Fragment;
import android.os.Bundle;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
/**
* Created by Tron on 1/5/2017.
*/
public class RadioFragment extends Fragment implements Button.OnClickListener {
Button buttonman;
View rootView;
PushStreamLink pushStreamLink;
Activity a;
@Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof Activity) {
//a = (Activity) context;
}
if (context instanceof PushStreamLink) {
pushStreamLink = (PushStreamLink) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement OnFragmentInteractionListener");
}
}
public RadioFragment(){
};
@Override
public View onCreateView(LayoutInflater inflater,ViewGroup container, Bundle savedInstanceState) {
rootView = inflater.inflate(R.layout.fragment_player, container, false);
buttonman = (Button)rootView.findViewById(R.id.buttonman);
buttonman.setOnClickListener(this);
return rootView;
}
@Override
public void onClick(View v) {
/*Fragment fragment = new StreamFragment();
FragmentManager fragmentManager = getActivity().getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.main_container, fragment);
fragmentTransaction.addToBackStack(null);
fragmentTransaction.commit();*/
//((MainActivity)a).performStreamClick();
pushStreamLink.sendStreamLink("www.zz.com");
}
}
StreamFragment（接收到数据但未保存在视图中的片段）
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
/**
* Created by Tron on 1/5/2017.
*/
public class StreamFragment extends Fragment {
String streamUrl="NoLinkFound";
TextView textView;
public StreamFragment(){};
@Override
public View onCreateView( LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_stream, container, false);
if(savedInstanceState==null)
{
}
else
{
streamUrl=savedInstanceState.getString("CurrentStreamLink");
textView =(TextView) getActivity().findViewById(R.id.streamLinkTextView);
textView.setText(streamUrl);
}
return view;
}
@Override
public void onSaveInstanceState(Bundle outState){
outState.putString("CurrentStreamLink",streamUrl);
super.onSaveInstanceState(outState);
}
@Override
public void onActivityCreated(Bundle savedInstanceState){
if (streamUrl!=null) {
// streamUrl = savedInstanceState.getString("CurrentStreamLink");
textView = (TextView) getActivity().findViewById(R.id.streamLinkTextView);
textView.setText(streamUrl);
}
super.onActivityCreated(savedInstanceState);
}
public void getUrl(String data)
{
streamUrl=data;
if (streamUrl!=null)
{
textView=(TextView) getActivity().findViewById(R.id.streamLinkTextView);
textView.setText(streamUrl);
}
}
}