当我更改屏幕方向时，应用程序崩溃。错误在map.java第23行。事实上，如果我删除这一行，当我更改屏幕的方向时，应用程序不会崩溃，但如果我转到Tab3然后返回到Map（Tab），则不会崩溃）。
有谁知道这个问题的解决方案？
MainActivity.java
package com.example.map;
import com.example.map.TabsPagerAdapter;
import android.support.v4.app.FragmentActivity;
import android.support.v4.view.ViewPager;
import android.app.ActionBar;
import android.app.FragmentTransaction;
import android.app.ActionBar.Tab;
import android.os.Bundle;
public class MainActivity extends FragmentActivity implements
ActionBar.TabListener {
private ViewPager viewPager;
private TabsPagerAdapter mAdapter;
private ActionBar actionBar;
// Tab titles
private String[] tabs = { "Map", "Tab2", "Tasb3" };
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Initilization
viewPager = (ViewPager) findViewById(R.id.pager);
actionBar = getActionBar();
mAdapter = new TabsPagerAdapter(getSupportFragmentManager());
viewPager.setAdapter(mAdapter);
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
actionBar.setDisplayOptions(ActionBar.DISPLAY_SHOW_CUSTOM);
actionBar.setDisplayShowHomeEnabled(true);
actionBar.setDisplayShowTitleEnabled(true);
// Adding Tabs
for (String tab_name : tabs) {
actionBar.addTab(actionBar.newTab().setText(tab_name).setTabListener(this));
}
viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageSelected(int position) {
// on changing the page
// make respected tab selected
actionBar.setSelectedNavigationItem(position);
}
@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
}
@Override
public void onPageScrollStateChanged(int arg0) {
}
});
}
@Override
public void onTabReselected(Tab arg0, FragmentTransaction arg1) {
// TODO Auto-generated method stub
}
@Override
public void onTabSelected(Tab tab, FragmentTransaction arg1) {
// TODO Auto-generated method stub
viewPager.setCurrentItem(tab.getPosition());
}
@Override
public void onTabUnselected(Tab arg0, FragmentTransaction arg1) {
// TODO Auto-generated method stub
}
}
TabsPagerAdapter.java
package com.example.map;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
public class TabsPagerAdapter extends FragmentPagerAdapter {
public TabsPagerAdapter(FragmentManager fm) {
super(fm);
}
@Override
public Fragment getItem(int index) {
switch (index) {
case 0:
return new map();
case 1:
return new tab2();
case 2:
return new tab3();
}
return null;
}
@Override
public int getCount() {
return 3;
}
}
map.java
package com.example.map;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
public class map extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.map, container, false);
}
@Override
public void onDestroyView() {
super.onDestroyView();
//This is the line that makes the application crash when changing the screen orientation
getFragmentManager().beginTransaction().remove(getFragmentManager().findFragmentById(R.id.location_map)).commit();
}
}
activity_main.xml中
<android.support.v4.view.ViewPager xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/pager"
android:layout_width="match_parent"
android:layout_height="match_parent">
</android.support.v4.view.ViewPager>
map.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<fragment
android:id="@+id/location_map"
android:layout_width="match_parent"
android:layout_height="match_parent"
class="com.google.android.gms.maps.SupportMapFragment" />
</RelativeLayout>
logcat的
08-11 19:39:26.639: D/AndroidRuntime(24966): Shutting down VM
08-11 19:39:26.639: W/dalvikvm(24966): threadid=1: thread exiting with uncaught exception (group=0x41616d88)
08-11 19:39:26.669: E/AndroidRuntime(24966): FATAL EXCEPTION: main
08-11 19:39:26.669: E/AndroidRuntime(24966): Process: com.example.map, PID: 24966
08-11 19:39:26.669: E/AndroidRuntime(24966): java.lang.RuntimeException: Unable to destroy activity {com.example.map/com.example.map.MainActivity}: java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.app.ActivityThread.performDestroyActivity(ActivityThread.java:3601)
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.app.ActivityThread.handleDestroyActivity(ActivityThread.java:3619)
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:3819)
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.app.ActivityThread.access$900(ActivityThread.java:144)
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1252)
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.os.Handler.dispatchMessage(Handler.java:102)
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.os.Looper.loop(Looper.java:212)
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.app.ActivityThread.main(ActivityThread.java:5151)
08-11 19:39:26.669: E/AndroidRuntime(24966): at java.lang.reflect.Method.invokeNative(Native Method)
08-11 19:39:26.669: E/AndroidRuntime(24966): at java.lang.reflect.Method.invoke(Method.java:515)
08-11 19:39:26.669: E/AndroidRuntime(24966): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
08-11 19:39:26.669: E/AndroidRuntime(24966): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:684)
08-11 19:39:26.669: E/AndroidRuntime(24966): at dalvik.system.NativeStart.main(Native Method)
08-11 19:39:26.669: E/AndroidRuntime(24966): Caused by: java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.support.v4.app.FragmentManagerImpl.checkStateLoss(FragmentManager.java:1360)
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.support.v4.app.FragmentManagerImpl.enqueueAction(FragmentManager.java:1378)
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.support.v4.app.BackStackRecord.commitInternal(BackStackRecord.java:595)
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.support.v4.app.BackStackRecord.commit(BackStackRecord.java:574)
08-11 19:39:26.669: E/AndroidRuntime(24966): at com.example.map.map.onDestroyView(map.java:23)
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.support.v4.app.Fragment.performDestroyView(Fragment.java:1709)
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1011)
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1121)
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1103)
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.support.v4.app.FragmentManagerImpl.dispatchDestroy(FragmentManager.java:1938)
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.support.v4.app.FragmentActivity.onDestroy(FragmentActivity.java:336)
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.app.Activity.performDestroy(Activity.java:5403)
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.app.Instrumentation.callActivityOnDestroy(Instrumentation.java:1117)
08-11 19:39:26.669: E/AndroidRuntime(24966): at android.app.ActivityThread.performDestroyActivity(ActivityThread.java:3588)
08-11 19:39:26.669: E/AndroidRuntime(24966): ... 12 more
08-11 19:39:35.659: I/Process(24966): Sending signal. PID: 24966 SIG: 9
好的，我按如下方式更改了代码，但问题仍未解决（onSaveInstanceState后无法执行此操作）
MainActivity.java
import android.app.ActionBar;
import android.app.ActionBar.Tab;
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.view.ViewPager;
public class MainActivity extends FragmentActivity implements
ActionBar.TabListener {
public static FragmentManager fragManager;
private ViewPager viewPager;
private TabsPagerAdapter mAdapter;
private ActionBar actionBar;
// Tab titles
private String[] tabs = { "Map", "Tab2", "Tab3" };
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
fragManager = getSupportFragmentManager();
// Initilization
viewPager = (ViewPager) findViewById(R.id.pager);
actionBar = getActionBar();
mAdapter = new TabsPagerAdapter(fragManager);
viewPager.setAdapter(mAdapter);
actionBar.setHomeButtonEnabled(false);
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
actionBar.setDisplayOptions(ActionBar.DISPLAY_SHOW_CUSTOM);
actionBar.setDisplayShowHomeEnabled(true);
actionBar.setDisplayShowTitleEnabled(true);
// Adding Tabs
for (String tab_name : tabs) {
actionBar.addTab(actionBar.newTab().setText(tab_name).setTabListener(this));
}
viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageSelected(int position) {
// on changing the page
// make respected tab selected
actionBar.setSelectedNavigationItem(position);
}
@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
}
@Override
public void onPageScrollStateChanged(int arg0) {
}
});
}
@Override
public void onTabReselected(Tab arg0, FragmentTransaction arg1) {
// TODO Auto-generated method stub
}
@Override
public void onTabSelected(Tab tab, FragmentTransaction arg1) {
// TODO Auto-generated method stub
viewPager.setCurrentItem(tab.getPosition());
}
@Override
public void onTabUnselected(Tab arg0, FragmentTransaction arg1) {
// TODO Auto-generated method stub
}
}
map.java
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import com.google.android.gms.maps.SupportMapFragment;
public class discover extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.discover, container, false);
Log.i("prova", "onCreateView");
return v;
}
@Override
public void onDestroyView() {
super.onDestroyView();
SupportMapFragment f = (SupportMapFragment) MainActivity.fragManager.findFragmentById(R.id.location_map);
if(f != null)
{
Log.i("prova", "onDestroyView");
MainActivity.fragManager.beginTransaction().remove(MainActivity.fragManager.findFragmentById(R.id.location_map)).commit();
}
}
}
logcat的
08-14 13:46:39.653: I/prova(19209): onDestroyView
08-14 13:46:39.653: D/AndroidRuntime(19209): Shutting down VM
08-14 13:46:39.653: W/dalvikvm(19209): threadid=1: thread exiting with uncaught exception (group=0x41616d88)
08-14 13:46:39.703: D/dalvikvm(19209): GC_FOR_ALLOC freed 638K, 12% free 49716K/56272K, paused 26ms, total 26ms
08-14 13:46:39.703: E/AndroidRuntime(19209): FATAL EXCEPTION: main
08-14 13:46:39.703: E/AndroidRuntime(19209): Process: com.example.map, PID: 19209
08-14 13:46:39.703: E/AndroidRuntime(19209): java.lang.RuntimeException: Unable to destroy activity {com.example.map/com.example.map.MainActivity}: java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.app.ActivityThread.performDestroyActivity(ActivityThread.java:3601)
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.app.ActivityThread.handleDestroyActivity(ActivityThread.java:3619)
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:3819)
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.app.ActivityThread.access$900(ActivityThread.java:144)
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1252)
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.os.Handler.dispatchMessage(Handler.java:102)
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.os.Looper.loop(Looper.java:212)
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.app.ActivityThread.main(ActivityThread.java:5151)
08-14 13:46:39.703: E/AndroidRuntime(19209): at java.lang.reflect.Method.invokeNative(Native Method)
08-14 13:46:39.703: E/AndroidRuntime(19209): at java.lang.reflect.Method.invoke(Method.java:515)
08-14 13:46:39.703: E/AndroidRuntime(19209): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
08-14 13:46:39.703: E/AndroidRuntime(19209): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:684)
08-14 13:46:39.703: E/AndroidRuntime(19209): at dalvik.system.NativeStart.main(Native Method)
08-14 13:46:39.703: E/AndroidRuntime(19209): Caused by: java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.support.v4.app.FragmentManagerImpl.checkStateLoss(FragmentManager.java:1360)
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.support.v4.app.FragmentManagerImpl.enqueueAction(FragmentManager.java:1378)
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.support.v4.app.BackStackRecord.commitInternal(BackStackRecord.java:595)
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.support.v4.app.BackStackRecord.commit(BackStackRecord.java:574)
08-14 13:46:39.703: E/AndroidRuntime(19209): at com.example.map.discover.onDestroyView(discover.java:31)
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.support.v4.app.Fragment.performDestroyView(Fragment.java:1709)
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1011)
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1121)
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1103)
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.support.v4.app.FragmentManagerImpl.dispatchDestroy(FragmentManager.java:1938)
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.support.v4.app.FragmentActivity.onDestroy(FragmentActivity.java:336)
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.app.Activity.performDestroy(Activity.java:5403)
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.app.Instrumentation.callActivityOnDestroy(Instrumentation.java:1117)
08-14 13:46:39.703: E/AndroidRuntime(19209): at android.app.ActivityThread.performDestroyActivity(ActivityThread.java:3588)
08-14 13:46:39.703: E/AndroidRuntime(19209): ... 12 more
08-14 13:46:43.183: I/Process(19209): Sending signal. PID: 19209 SIG: 9
答案 0 :(得分：0)
我正在这样做。这是为了在你的情况下将一个标签移动到另一个标签，并在此网站上进行轮换搜索和saveinstantsate。当你保存当前状态时，不要调用ondestroyview方法
package com.sunil.assignment;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.GoogleMap.OnMarkerClickListener;
import com.google.android.gms.maps.MapFragment;
import com.google.android.gms.maps.UiSettings;
import com.google.android.gms.maps.model.BitmapDescriptor;
import com.google.android.gms.maps.model.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;
import com.sunil.assignment.R.drawable;
import android.app.Fragment;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.BitmapFactory.Options;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.Toast;
public class First extends Fragment{
FragmentManager man;
private GoogleMap googleMap;
MapFragment mMapFragment;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
View v=inflater.inflate(R.layout.firstscreen, container, false);
try {
// Loading map
initilizeMap();
} catch (Exception e)
{
e.printStackTrace();
}
LatLng mumbai=new LatLng(18.9300, 72.8200);
googleMap.getUiSettings().setZoomControlsEnabled(true);
googleMap.moveCamera(CameraUpdateFactory.newLatLngZoom(mumbai, 13));
// googleMap.addMarker(new MarkerOptions().title("Mumbai").snippet("Dream City").position(mumbai));
// latitude and longitude
double latitude = 18.9300;
double longitude = 72.8200;
// create marker
final MarkerOptions marker = new MarkerOptions().position(new LatLng(latitude, longitude)).title("Hello");
// adding marker
googleMap.addMarker(marker);
googleMap.setOnMarkerClickListener(new GoogleMap.OnMarkerClickListener() {
@Override
public boolean onMarkerClick(Marker arg0) {
// TODO Auto-generated method stub
Toast.makeText(getActivity(), "Churchgate", Toast.LENGTH_SHORT).show();
googleMap.addMarker( marker.
icon(BitmapDescriptorFactory.fromResource(R.drawable.images)).title("Mumbai").snippet("Dream City").
position(new LatLng(18.9300,72.8200)));
return true;
}
});
return v;
}
/**
* function to load map. If map is not created it will create it for you
* */
private void initilizeMap() {
/*
mMapFragment = (MapFragment) getFragmentManager().findFragmentById(R.id.map);
if (mMapFragment == null) {
FragmentManager fragmentManager = getFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
mMapFragment = MapFragment.newInstance();
fragmentTransaction.replace(R.id.map, mMapFragment).commit();
Toast.makeText(getActivity(), "null", Toast.LENGTH_SHORT).show();
}
if (mMapFragment != null)
{
googleMap = mMapFragment.getMap();
Toast.makeText(getActivity(), "hi", Toast.LENGTH_SHORT).show();
if (googleMap != null)
googleMap.setOnMapClickListener(new GoogleMap. OnMapClickListener()
{
@Override
public void onMapClick(LatLng point)
{
//TODO: your onclick stuffs
Toast.makeText(getActivity(), "hi", Toast.LENGTH_SHORT).show();
}
});
} */
if (googleMap == null) {
googleMap = ((MapFragment) getFragmentManager().findFragmentById(
R.id.map)).getMap();
// check if map is created successfully or not
if (googleMap == null) {
Toast.makeText(getActivity(),
"Sorry! unable to create maps", Toast.LENGTH_SHORT)
.show();
}
}
}
@Override
public void onDestroyView() {
super.onDestroyView();
MapFragment f = (MapFragment) getFragmentManager()
.findFragmentById(R.id.map);
if (f != null)
getFragmentManager().beginTransaction().remove(f).commit();
}
}
答案 1 :(得分：0)
我通过添加try catch解决了这个问题，现在应用程序没有崩溃，但它不是一个优雅的解决方案，任何人都知道其他解决方案？
<强> map.java
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
public class discover extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.discover, container, false);
return v;
}
@Override
public void onDestroyView() {
super.onDestroyView();
try
{
MainActivity.fragManager.beginTransaction().remove(MainActivity.fragManager.findFragmentById(R.id.location_map)).commit();
}
catch(Exception e)
{
}
}
}