onCreateLoader不叫时,方向更改 [英] onCreateLoader not called when orientation changes
问题描述
我的问题是基本相同的这一个:<一href="http://stackoverflow.com/questions/7810019/sometimes-dont-get-oncreateloader-callback-after-calling-initloader">Sometimes不要onCreateLoader调用回调后initLoader
我有2 ListFragments
包含在一个 ViewPager
。他们首先被装入好的,但是当我改变方向, initLoader
方法不叫 onCreateLoader
。
不过,如果我恢复到初始取向,一切又是罚款。
下面是我的code为 FragmentActivity
:
进口java.util.Locale中;
进口com.d.camera.R;
进口com.d.camera.R.id;
进口com.d.camera.R.layout;
进口com.d.camera.R.menu;
进口com.d.camera.R.string;
进口android.app.ActionBar;
进口android.app.FragmentTransaction;
进口android.os.Bundle;
进口android.support.v4.app.Fragment;
进口android.support.v4.app.FragmentActivity;
进口android.support.v4.app.FragmentManager;
进口android.support.v4.app.FragmentPagerAdapter;
进口android.support.v4.app.NavUtils;
进口android.support.v4.view.ViewPager;
进口android.view.Gravity;
进口android.view.LayoutInflater;
进口android.view.Menu;
进口android.view.MenuItem;
进口android.view.View;
进口android.view.ViewGroup;
进口android.widget.TextView;
公共类HistoryFragments扩展FragmentActivity工具
ActionBar.TabListener {
/ **
*在{@link android.support.v4.view.PagerAdapter},将提供
*对于每个部分的片段。我们使用
* {@link android.support.v4.app.FragmentPagerAdapter}衍生物,它
*将让每一个加载的片段记忆。如果这成为过记忆
*密集,它可能是最好切换到
* {@link android.support.v4.app.FragmentStatePagerAdapter}。
* /
SectionsPagerAdapter mSectionsPagerAdapter;
/ **
*在{@link ViewPager}将承载部分内容。
* /
ViewPager mViewPager;
@覆盖
保护无效的onCreate(包savedInstanceState){
super.onCreate(savedInstanceState);
的setContentView(R.layout.activity_history_fragments);
//设置操作栏。
最后的动作条动作条= getActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
actionBar.setDisplayShowTitleEnabled(假);
actionBar.setDisplayShowHomeEnabled(假);
//创建将返回一个片段为三个的适配器
//应用程序的主要部分。
mSectionsPagerAdapter =新SectionsPagerAdapter(
getSupportFragmentManager());
//设置的ViewPager与部分适配器。
mViewPager =(ViewPager)findViewById(R.id.pager);
mViewPager.setAdapter(mSectionsPagerAdapter);
//当不同部分之间的刷卡,选择相应的
//标签。我们也可以使用ActionBar.Tab#选择()要做到这一点,如果我们有
//引用的标签。
mViewPager
.setOnPageChangeListener(新ViewPager.SimpleOnPageChangeListener(){
@覆盖
公共无效onPageSelected(INT位置){
actionBar.setSelectedNavigationItem(位置);
}
});
//对于每个应用程序的章节中,添加一个标签,操作栏。
的for(int i = 0; I&LT; mSectionsPagerAdapter.getCount();我++){
//创建与对应于由所定义的页标题文本标签
//适配器。同时,指定此活动的对象,它实现
//该TabListener界面,回调(监听程序)进行时
//这个选项卡中选择。
actionBar.addTab(actionBar.newTab()
.setText(mSectionsPagerAdapter.getPageTitle(I))
.setTabListener(本));
}
}
@覆盖
公共布尔onCreateOptionsMenu(功能菜单){
//充气菜单;这增加了项目操作栏,如果它是present。
。getMenuInflater()膨胀(R.menu.history,菜单);
返回true;
}
@覆盖
公共无效onTabSelected(ActionBar.Tab选项卡,
FragmentTransaction fragmentTransaction){
//当选择给定的标签,切换到对应页面
//该ViewPager。
mViewPager.setCurrentItem(tab.getPosition());
}
@覆盖
公共无效onTabUnselected(ActionBar.Tab选项卡,
FragmentTransaction fragmentTransaction){
}
@覆盖
公共无效onTabReselected(ActionBar.Tab选项卡,
FragmentTransaction fragmentTransaction){
}
/ **
* A {@link FragmentPagerAdapter}返回对应的片段
*章节/标签/页之一。
* /
公共类SectionsPagerAdapter扩展FragmentPagerAdapter {
公共SectionsPagerAdapter(FragmentManager FM){
超(FM);
}
@覆盖
公共片段的getItem(INT位置){
//的getItem被称为实例化片段给定的页面。
//返回一个DummySectionFragment(定义为静态内部类
下图)与页面数量作为其唯一的参数//。
片段片段= NULL;
如果(位置== 0){
片段=新HistoryListFragment();
} 其他{
片段=新HistoryElemListFragment();
}
返回片段;
}
@覆盖
公众诠释getCount将(){
//显示2总页数。
返回2;
}
@覆盖
公共CharSequence的getPageTitle(INT位置){
区域设置L = Locale.getDefault();
开关(位置){
情况下0:
返回的getString(R.string.title_section1).toUpperCase(升);
情况1:
返回的getString(R.string.title_section2).toUpperCase(升);
案例2:
返回的getString(R.string.title_section3).toUpperCase(升);
}
返回null;
}
}
}
和这里是之一code中的 ListFragments
:
进口的java.io.File;
进口java.text.SimpleDateFormat的;
进口java.util.Date;
进口java.util.Locale中;
进口com.d.camera.HistoryContentProvider;
进口com.d.camera.HistoryDatabase;
进口com.d.camera.HistoryEntry;
进口com.d.camera.R;
进口android.app.LoaderManager;
进口android.content.Context;
进口android.content.CursorLoader;
进口android.content.Intent;
进口android.content.Loader;
进口android.database.Cursor;
进口android.net.Uri;
进口android.os.Bundle;
进口android.support.v4.app.ListFragment;
进口android.util.Log;
进口android.view.ContextMenu;
进口android.view.LayoutInflater;
进口android.view.Menu;
进口android.view.MenuItem;
进口android.view.View;
进口android.view.ContextMenu.ContextMenuInfo;
进口android.view.ViewGroup;
进口android.widget.FilterQueryProvider;
进口android.widget.ListView;
进口android.widget.SimpleCursorAdapter;
进口android.widget.TextView;
进口android.widget.AdapterView.AdapterContextMenuInfo;
进口android.widget.SimpleCursorAdapter.ViewBinder;
公共类HistoryListFragment扩展ListFragment实现LoaderManager.LoaderCallbacks&LT;光标&GT; {
私有静态最终诠释LOADER_ID = 0×01;
私有静态最终诠释DELETE_ID = Menu.FIRST + 1;
公共静态最后弦乐SECTION_NUMBER =section_number标;
私人SimpleCursorAdapter适配器;
私人上下文的背景下;
公共HistoryListFragment(){
}
@覆盖
公共无效onActivityCreated(包savedInstanceState){
super.onActivityCreated(savedInstanceState);
上下文= getActivity();
fillData();
registerForContextMenu(getListView());
}
@覆盖
公共查看onCreateView(LayoutInflater充气,容器的ViewGroup,
捆绑savedInstanceState){
查看rootView = inflater.inflate(R.layout.list_fragment,集装箱,假);
返回rootView;
}
私人无效fillData(){
。getActivity()getLoaderManager()initLoader(LOADER_ID,空,这一点)。
的String []从=新的String [] {
HistoryDatabase.MOBILE_RESULT,
HistoryDatabase.FP_TIMESTAMP,
HistoryDatabase.PRODUCT_IMAGE,};
INT []到=新INT [] {
R.id.resultImage,
R.id.time,
R.id.productImage,};
适配器=新SimpleCursorAdapter(背景下,R.layout.history_element,空,从到,0);
//我们要监视列表的设置和时间变化毫秒到可读的格式。*******
adapter.setViewBinder(新ViewBinder(){
公共布尔setViewValue(视图V,光标C中,int参数:columnIndex){
如果(参数:columnIndex == c.getColumnIndex(HistoryDatabase.FP_TIMESTAMP))
{
龙timeInMilli = c.getLong(c.getColumnIndex(HistoryDatabase.FP_TIMESTAMP));
SimpleDateFormat的SDF =新的SimpleDateFormat(EEE MMM DD HH:MM:SSžYYYY,Locale.ENGLISH);
字符串formatedTime = sdf.format(新日期(timeInMilli));
TextView的电视=(TextView中)V;
tv.setText(formatedTime);
返回true;
}
返回false;
}
});
// ********** *********************************************
setListAdapter(适配器);
}
@覆盖
公共无效onCreateContextMenu(文本菜单菜单,视图V,
ContextMenuInfo menuInfo){
super.onCreateContextMenu(菜单,V,menuInfo);
menu.add(0,DELETE_ID,0,R.string.menu_delete);
}
@覆盖
公共布尔onContextItemSelected(菜单项项){
// ...
返回super.onContextItemSelected(项目);
}
//反应到菜单选择
@覆盖
公共布尔onOptionsItemSelected(菜单项项){
// ...
返回super.onOptionsItemSelected(项目);
}
@覆盖
公共装载机&LT;光标&GT; onCreateLoader(INT ID,捆绑参数){
的String []投影=新的String [] {HistoryDatabase.ID,HistoryDatabase.MOBILE_RESULT,HistoryDatabase.MOBILE_SCORE,HistoryDatabase.FP_TIMESTAMP,HistoryDatabase.PRODUCT_IMAGE,HistoryDatabase.QR_MESSAGE};
返回新CursorLoader(背景下,HistoryContentProvider.CONTENT_URI,投影,NULL,NULL,HistoryDatabase.ID +降序);
}
@覆盖
公共无效onLoadFinished(装载机&LT;光标&GT; cursorLoader,光标光标){
adapter.swapCursor(光标);
}
@覆盖
公共无效onLoaderReset(装载机&LT;光标&GT; cursorLoader){
adapter.swapCursor(空);
}
公共无效onListItemClick(ListView的L,视图V,INT位置,长的id){
//做一点事
}
}
我已经试过这些方法 destroyLoader
, restartLoader
不同的组合,但没有任何成功...是否任何人都知道这是怎么回事?
修改
使用 LoaderManager.enableDebugLogging(真)
我得到以下日志:
第一负载给出了这样的
initLoader在LoaderManager {在HistoryFragments {424a7950 42507c68}}参数:args = NULL
首发:{的LoaderInfo#424a7da0 1:CursorLoader {42faae18}}
创建新的装载机的LoaderInfo {424a7da0#1:CursorLoader {42faae18}}
initLoader在LoaderManager {在HistoryFragments {424a7950 42507c68}}参数:args = NULL
首发:{的LoaderInfo#42e5a280 2:CursorLoader {42e5a2f8}}
创建新的装载机的LoaderInfo {42e5a280#2:CursorLoader {42e5a2f8}}
的onLoadComplete:{的LoaderInfo#424a7da0 1:CursorLoader {42faae18}}
onLoadFinished在CursorLoader {42faae18 ID = 1}:CursorWrapperInner {42506d58}
的onLoadComplete:{的LoaderInfo#42e5a280 2:CursorLoader {42e5a2f8}}
onLoadFinished在CursorLoader {42e5a2f8 ID = 2}:{CursorWrapperInner 42fab1f0}
然后当我改变方向,它给这个
护在LoaderManager {424a7950在HistoryFragments {42507c68}}
护:{的LoaderInfo#42e5a280 2:CursorLoader {42e5a2f8}}
护:{的LoaderInfo#424a7da0 1:CursorLoader {42faae18}}
销毁不活动的LoaderManager {在HistoryFragments 424a7950 {42507c68}}
initLoader在LoaderManager {在HistoryFragments {424a7950 426d0af0}}参数:args = NULL
重新使用现有的装载机的LoaderInfo {424a7da0#1:CursorLoader {42faae18}}
initLoader在LoaderManager {在HistoryFragments {424a7950 426d0af0}}参数:args = NULL
重新使用现有的装载机的LoaderInfo {42e5a280#2:CursorLoader {42e5a2f8}}
在LoaderManager成品护{424a7950在HistoryFragments {426d0af0}}
成品护:{的LoaderInfo#42e5a280 2:CursorLoader {42e5a2f8}}
停止:{的LoaderInfo#42e5a280 2:CursorLoader {42e5a2f8}}
成品护:{的LoaderInfo#424a7da0 1:CursorLoader {42faae18}}
停止:{的LoaderInfo#424a7da0 1:CursorLoader {42faae18}}
然后,当我再回到最初的方向,我得到一个错误,但随后一切都被再次加载:
保留在LoaderManager {在HistoryFragments {424a7950 426d0af0}}
调用doRetain时,不启动:LoaderManager {424a7950在HistoryFragments {426d0af0}}
java.lang.RuntimeException的:在这里
在android.app.LoaderManagerImpl.doRetain(LoaderManager.java:795)
在android.app.Activity.performStop(Activity.java:5497)
在android.app.ActivityThread.performDestroyActivity(ActivityThread.java:3591)
在android.app.ActivityThread.handleDestroyActivity(ActivityThread.java:3654)
在android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:3854)
在android.app.ActivityThread.access $ 800(ActivityThread.java:159)
在android.app.ActivityThread $ H.handleMessage(ActivityThread.java:1322)
在android.os.Handler.dispatchMessage(Handler.java:99)
在android.os.Looper.loop(Looper.java:176)
在android.app.ActivityThread.main(ActivityThread.java:5419)
在java.lang.reflect.Method.invokeNative(本机方法)
在java.lang.reflect.Method.invoke(Method.java:525)
在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:1046)
在com.android.internal.os.ZygoteInit.main(ZygoteInit.java:862)
在dalvik.system.NativeStart.main(本机方法)
销毁活动在LoaderManager {在HistoryFragments 424a7950 {426d0af0}}
销毁:{的LoaderInfo#42e5a280 2:CursorLoader {42e5a2f8}}
CH375复位:{的LoaderInfo#42e5a280 2:CursorLoader {42e5a2f8}}
销毁:{的LoaderInfo#424a7da0 1:CursorLoader {42faae18}}
CH375复位:{的LoaderInfo#424a7da0 1:CursorLoader {42faae18}}
销毁不活动的LoaderManager {在HistoryFragments 424a7950 {426d0af0}}
销毁活动在LoaderManager {在HistoryFragments 424a7950 {426d0af0}}
销毁不活动的LoaderManager {在HistoryFragments 424a7950 {426d0af0}}
initLoader在LoaderManager {在HistoryFragments {4271b070 42702c68}}参数:args = NULL
首发:{的LoaderInfo#4271b690 1:CursorLoader {4271b708}}
创建新的装载机的LoaderInfo {4271b690#1:CursorLoader {4271b708}}
initLoader在LoaderManager {在HistoryFragments {4271b070 42702c68}}参数:args = NULL
首发:{的LoaderInfo#42720ab8 2:CursorLoader {42720b30}}
创建新的装载机的LoaderInfo {42720ab8#2:CursorLoader {42720b30}}
的onLoadComplete:{的LoaderInfo#4271b690 1:CursorLoader {4271b708}}
onLoadFinished在CursorLoader {4271b708 ID = 1}:CursorWrapperInner {4271f518}
的onLoadComplete:{的LoaderInfo#42720ab8 2:CursorLoader {42720b30}}
onLoadFinished在CursorLoader {42720b30 ID = 2}:{CursorWrapperInner 427222c0}
日志然后重复自己进一步的方向改变。为什么在 CursorLoaders
被停止,并没有重新启动?我该如何重新启动呢?
编辑2
我固定我的问题感谢Nikis街,但他提出了一个有趣的问题:
为什么是 android.app.LoaderManager
不工作?
下面是使用支持版本后,日志。 第一负载给出了同样的事情上面,但方向改变后,再使用光标不会阻止他们。
护在LoaderManager {43945c70在HistoryFragments {427cb468}}
护:{的LoaderInfo#439d8a58 2:CursorLoader {439d8ad0}}
护:{的LoaderInfo#432dea88 1:CursorLoader {4393ad48}}
销毁不活动的LoaderManager {在HistoryFragments 43945c70 {427cb468}}
initLoader在LoaderManager {在HistoryFragments {43945c70 438f0a38}}参数:args = NULL
重新使用现有的装载机的LoaderInfo {432dea88#1:CursorLoader {4393ad48}}
initLoader在LoaderManager {在HistoryFragments {43945c70 438f0a38}}参数:args = NULL
重新使用现有的装载机的LoaderInfo {439d8a58#2:CursorLoader {439d8ad0}}
开始在LoaderManager {在HistoryFragments 43945c70 {438f0a38}}
在LoaderManager成品护{43945c70在HistoryFragments {438f0a38}}
成品护:{的LoaderInfo#439d8a58 2:CursorLoader {439d8ad0}}
onLoadFinished在CursorLoader {439d8ad0 ID = 2}:{CursorWrapperInner 43952be0}
成品护:{的LoaderInfo#432dea88 1:CursorLoader {4393ad48}}
onLoadFinished在CursorLoader {4393ad48 ID = 1}:CursorWrapperInner {43952fa8}
当我再回到最初的方向,这是结果:
护在LoaderManager {43945c70在HistoryFragments {438f0a38}}
护:{的LoaderInfo#439d8a58 2:CursorLoader {439d8ad0}}
护:{的LoaderInfo#432dea88 1:CursorLoader {4393ad48}}
销毁不活动的LoaderManager {在HistoryFragments 43945c70 {438f0a38}}
initLoader在LoaderManager {在HistoryFragments {43945c70 432cab50}}参数:args = NULL
重新使用现有的装载机的LoaderInfo {432dea88#1:CursorLoader {4393ad48}}
initLoader在LoaderManager {在HistoryFragments {43945c70 432cab50}}参数:args = NULL
重新使用现有的装载机的LoaderInfo {439d8a58#2:CursorLoader {439d8ad0}}
开始在LoaderManager {在HistoryFragments 43945c70 {432cab50}}
在LoaderManager成品护{43945c70在HistoryFragments {432cab50}}
成品护:{的LoaderInfo#439d8a58 2:CursorLoader {439d8ad0}}
onLoadFinished在CursorLoader {439d8ad0 ID = 2}:{CursorWrapperInner 43952be0}
成品护:{的LoaderInfo#432dea88 1:CursorLoader {4393ad48}}
onLoadFinished在CursorLoader {4393ad48 ID = 1}:CursorWrapperInner {43952fa8}
您可以使用 LoaderManager.enableDebugLogging(真)
来调试器行为,或者你可以尝试使用 getSupportLoadermanager()
而不是 getLoaderManager()
My problem is basically the same as this one:Sometimes don't get onCreateLoader callback after calling initLoader
I have 2 ListFragments
that are contained in a ViewPager
. They get loaded ok at first, but when I change the orientation, the initLoader
method doesn't call the onCreateLoader
.
However, if I revert back to the initial orientation, all is fine again.
Here is my code for the FragmentActivity
:
import java.util.Locale;
import com.d.camera.R;
import com.d.camera.R.id;
import com.d.camera.R.layout;
import com.d.camera.R.menu;
import com.d.camera.R.string;
import android.app.ActionBar;
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.app.NavUtils;
import android.support.v4.view.ViewPager;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
public class HistoryFragments extends FragmentActivity implements
ActionBar.TabListener {
/**
* The {@link android.support.v4.view.PagerAdapter} that will provide
* fragments for each of the sections. We use a
* {@link android.support.v4.app.FragmentPagerAdapter} derivative, which
* will keep every loaded fragment in memory. If this becomes too memory
* intensive, it may be best to switch to a
* {@link android.support.v4.app.FragmentStatePagerAdapter}.
*/
SectionsPagerAdapter mSectionsPagerAdapter;
/**
* The {@link ViewPager} that will host the section contents.
*/
ViewPager mViewPager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_history_fragments);
// Set up the action bar.
final ActionBar actionBar = getActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
actionBar.setDisplayShowTitleEnabled(false);
actionBar.setDisplayShowHomeEnabled(false);
// Create the adapter that will return a fragment for each of the three
// primary sections of the app.
mSectionsPagerAdapter = new SectionsPagerAdapter(
getSupportFragmentManager());
// Set up the ViewPager with the sections adapter.
mViewPager = (ViewPager) findViewById(R.id.pager);
mViewPager.setAdapter(mSectionsPagerAdapter);
// When swiping between different sections, select the corresponding
// tab. We can also use ActionBar.Tab#select() to do this if we have
// a reference to the Tab.
mViewPager
.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
@Override
public void onPageSelected(int position) {
actionBar.setSelectedNavigationItem(position);
}
});
// For each of the sections in the app, add a tab to the action bar.
for (int i = 0; i < mSectionsPagerAdapter.getCount(); i++) {
// Create a tab with text corresponding to the page title defined by
// the adapter. Also specify this Activity object, which implements
// the TabListener interface, as the callback (listener) for when
// this tab is selected.
actionBar.addTab(actionBar.newTab()
.setText(mSectionsPagerAdapter.getPageTitle(i))
.setTabListener(this));
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.history, menu);
return true;
}
@Override
public void onTabSelected(ActionBar.Tab tab,
FragmentTransaction fragmentTransaction) {
// When the given tab is selected, switch to the corresponding page in
// the ViewPager.
mViewPager.setCurrentItem(tab.getPosition());
}
@Override
public void onTabUnselected(ActionBar.Tab tab,
FragmentTransaction fragmentTransaction) {
}
@Override
public void onTabReselected(ActionBar.Tab tab,
FragmentTransaction fragmentTransaction) {
}
/**
* A {@link FragmentPagerAdapter} that returns a fragment corresponding to
* one of the sections/tabs/pages.
*/
public class SectionsPagerAdapter extends FragmentPagerAdapter {
public SectionsPagerAdapter(FragmentManager fm) {
super(fm);
}
@Override
public Fragment getItem(int position) {
// getItem is called to instantiate the fragment for the given page.
// Return a DummySectionFragment (defined as a static inner class
// below) with the page number as its lone argument.
Fragment fragment = null;
if (position == 0) {
fragment = new HistoryListFragment();
} else{
fragment = new HistoryElemListFragment();
}
return fragment;
}
@Override
public int getCount() {
// Show 2 total pages.
return 2;
}
@Override
public CharSequence getPageTitle(int position) {
Locale l = Locale.getDefault();
switch (position) {
case 0:
return getString(R.string.title_section1).toUpperCase(l);
case 1:
return getString(R.string.title_section2).toUpperCase(l);
case 2:
return getString(R.string.title_section3).toUpperCase(l);
}
return null;
}
}
}
and here is the code of one of the ListFragments
:
import java.io.File;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
import com.d.camera.HistoryContentProvider;
import com.d.camera.HistoryDatabase;
import com.d.camera.HistoryEntry;
import com.d.camera.R;
import android.app.LoaderManager;
import android.content.Context;
import android.content.CursorLoader;
import android.content.Intent;
import android.content.Loader;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.ListFragment;
import android.util.Log;
import android.view.ContextMenu;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ContextMenu.ContextMenuInfo;
import android.view.ViewGroup;
import android.widget.FilterQueryProvider;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
import android.widget.TextView;
import android.widget.AdapterView.AdapterContextMenuInfo;
import android.widget.SimpleCursorAdapter.ViewBinder;
public class HistoryListFragment extends ListFragment implements LoaderManager.LoaderCallbacks<Cursor>{
private static final int LOADER_ID = 0x01;
private static final int DELETE_ID = Menu.FIRST + 1;
public static final String SECTION_NUMBER = "section_number";
private SimpleCursorAdapter adapter;
private Context context;
public HistoryListFragment() {
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
context = getActivity();
fillData();
registerForContextMenu(getListView());
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.list_fragment, container, false);
return rootView;
}
private void fillData() {
getActivity().getLoaderManager().initLoader(LOADER_ID, null, this);
String[] from = new String[] {
HistoryDatabase.MOBILE_RESULT,
HistoryDatabase.FP_TIMESTAMP,
HistoryDatabase.PRODUCT_IMAGE,};
int[] to = new int[] {
R.id.resultImage,
R.id.time,
R.id.productImage,};
adapter = new SimpleCursorAdapter(context, R.layout.history_element, null, from, to, 0);
// We want monitor the list setup and change the milliseconds time to a readable format.*******
adapter.setViewBinder(new ViewBinder(){
public boolean setViewValue(View v, Cursor c, int columnIndex) {
if(columnIndex == c.getColumnIndex(HistoryDatabase.FP_TIMESTAMP))
{
Long timeInMilli = c.getLong(c.getColumnIndex(HistoryDatabase.FP_TIMESTAMP));
SimpleDateFormat sdf = new SimpleDateFormat("EEE MMM dd HH:mm:ss z yyyy", Locale.ENGLISH);
String formatedTime = sdf.format(new Date(timeInMilli));
TextView tv = (TextView)v;
tv.setText(formatedTime);
return true;
}
return false;
}
});
//*********************************************************************************************
setListAdapter(adapter);
}
@Override
public void onCreateContextMenu(ContextMenu menu, View v,
ContextMenuInfo menuInfo) {
super.onCreateContextMenu(menu, v, menuInfo);
menu.add(0, DELETE_ID, 0, R.string.menu_delete);
}
@Override
public boolean onContextItemSelected(MenuItem item) {
//...
return super.onContextItemSelected(item);
}
// Reaction to the menu selection
@Override
public boolean onOptionsItemSelected(MenuItem item) {
//...
return super.onOptionsItemSelected(item);
}
@Override
public Loader<Cursor> onCreateLoader(int id, Bundle args) {
String[] projection = new String[]{HistoryDatabase.ID, HistoryDatabase.MOBILE_RESULT, HistoryDatabase.MOBILE_SCORE, HistoryDatabase.FP_TIMESTAMP, HistoryDatabase.PRODUCT_IMAGE, HistoryDatabase.QR_MESSAGE};
return new CursorLoader(context, HistoryContentProvider.CONTENT_URI, projection, null, null, HistoryDatabase.ID + " DESC");
}
@Override
public void onLoadFinished(Loader<Cursor> cursorLoader, Cursor cursor) {
adapter.swapCursor(cursor);
}
@Override
public void onLoaderReset(Loader<Cursor> cursorLoader) {
adapter.swapCursor(null);
}
public void onListItemClick(ListView l, View v, int position, long id) {
//do something
}
}
I've tried different combinations of these methods destroyLoader
,restartLoader
, but without any success... Does anyone know what's going on?
Edit
Using LoaderManager.enableDebugLogging(true)
I get the following logs:
The first load gives this
initLoader in LoaderManager{424a7950 in HistoryFragments{42507c68}}: args=null
Starting: LoaderInfo{424a7da0 #1 : CursorLoader{42faae18}}
Created new loader LoaderInfo{424a7da0 #1 : CursorLoader{42faae18}}
initLoader in LoaderManager{424a7950 in HistoryFragments{42507c68}}: args=null
Starting: LoaderInfo{42e5a280 #2 : CursorLoader{42e5a2f8}}
Created new loader LoaderInfo{42e5a280 #2 : CursorLoader{42e5a2f8}}
onLoadComplete: LoaderInfo{424a7da0 #1 : CursorLoader{42faae18}}
onLoadFinished in CursorLoader{42faae18 id=1}: CursorWrapperInner{42506d58}
onLoadComplete: LoaderInfo{42e5a280 #2 : CursorLoader{42e5a2f8}}
onLoadFinished in CursorLoader{42e5a2f8 id=2}: CursorWrapperInner{42fab1f0}
Then when I change the orientation, it gives this
Retaining in LoaderManager{424a7950 in HistoryFragments{42507c68}}
Retaining: LoaderInfo{42e5a280 #2 : CursorLoader{42e5a2f8}}
Retaining: LoaderInfo{424a7da0 #1 : CursorLoader{42faae18}}
Destroying Inactive in LoaderManager{424a7950 in HistoryFragments{42507c68}}
initLoader in LoaderManager{424a7950 in HistoryFragments{426d0af0}}: args=null
Re-using existing loader LoaderInfo{424a7da0 #1 : CursorLoader{42faae18}}
initLoader in LoaderManager{424a7950 in HistoryFragments{426d0af0}}: args=null
Re-using existing loader LoaderInfo{42e5a280 #2 : CursorLoader{42e5a2f8}}
Finished Retaining in LoaderManager{424a7950 in HistoryFragments{426d0af0}}
Finished Retaining: LoaderInfo{42e5a280 #2 : CursorLoader{42e5a2f8}}
Stopping: LoaderInfo{42e5a280 #2 : CursorLoader{42e5a2f8}}
Finished Retaining: LoaderInfo{424a7da0 #1 : CursorLoader{42faae18}}
Stopping: LoaderInfo{424a7da0 #1 : CursorLoader{42faae18}}
Then when I come back to the initial orientation, I get an error but then everything gets loaded again:
Retaining in LoaderManager{424a7950 in HistoryFragments{426d0af0}}
Called doRetain when not started: LoaderManager{424a7950 in HistoryFragments{426d0af0}}
java.lang.RuntimeException: here
at android.app.LoaderManagerImpl.doRetain(LoaderManager.java:795)
at android.app.Activity.performStop(Activity.java:5497)
at android.app.ActivityThread.performDestroyActivity(ActivityThread.java:3591)
at android.app.ActivityThread.handleDestroyActivity(ActivityThread.java:3654)
at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:3854)
at android.app.ActivityThread.access$800(ActivityThread.java:159)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1322)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:176)
at android.app.ActivityThread.main(ActivityThread.java:5419)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1046)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:862)
at dalvik.system.NativeStart.main(Native Method)
Destroying Active in LoaderManager{424a7950 in HistoryFragments{426d0af0}}
Destroying: LoaderInfo{42e5a280 #2 : CursorLoader{42e5a2f8}}
Reseting: LoaderInfo{42e5a280 #2 : CursorLoader{42e5a2f8}}
Destroying: LoaderInfo{424a7da0 #1 : CursorLoader{42faae18}}
Reseting: LoaderInfo{424a7da0 #1 : CursorLoader{42faae18}}
Destroying Inactive in LoaderManager{424a7950 in HistoryFragments{426d0af0}}
Destroying Active in LoaderManager{424a7950 in HistoryFragments{426d0af0}}
Destroying Inactive in LoaderManager{424a7950 in HistoryFragments{426d0af0}}
initLoader in LoaderManager{4271b070 in HistoryFragments{42702c68}}: args=null
Starting: LoaderInfo{4271b690 #1 : CursorLoader{4271b708}}
Created new loader LoaderInfo{4271b690 #1 : CursorLoader{4271b708}}
initLoader in LoaderManager{4271b070 in HistoryFragments{42702c68}}: args=null
Starting: LoaderInfo{42720ab8 #2 : CursorLoader{42720b30}}
Created new loader LoaderInfo{42720ab8 #2 : CursorLoader{42720b30}}
onLoadComplete: LoaderInfo{4271b690 #1 : CursorLoader{4271b708}}
onLoadFinished in CursorLoader{4271b708 id=1}: CursorWrapperInner{4271f518}
onLoadComplete: LoaderInfo{42720ab8 #2 : CursorLoader{42720b30}}
onLoadFinished in CursorLoader{42720b30 id=2}: CursorWrapperInner{427222c0}
The logs then repeat themselves for further orientation changes. Why are the CursorLoaders
being stopped and not restarted? How can I restart them?
EDIT 2
I fixed my problem thanks to nikis, but he raised an interesting question:
why was the android.app.LoaderManager
not working?
Here's the logs after using the support version. The first load gives the same thing as above, but after the orientation change, re-using the cursors doesn't stop them.
Retaining in LoaderManager{43945c70 in HistoryFragments{427cb468}}
Retaining: LoaderInfo{439d8a58 #2 : CursorLoader{439d8ad0}}
Retaining: LoaderInfo{432dea88 #1 : CursorLoader{4393ad48}}
Destroying Inactive in LoaderManager{43945c70 in HistoryFragments{427cb468}}
initLoader in LoaderManager{43945c70 in HistoryFragments{438f0a38}}: args=null
Re-using existing loader LoaderInfo{432dea88 #1 : CursorLoader{4393ad48}}
initLoader in LoaderManager{43945c70 in HistoryFragments{438f0a38}}: args=null
Re-using existing loader LoaderInfo{439d8a58 #2 : CursorLoader{439d8ad0}}
Starting in LoaderManager{43945c70 in HistoryFragments{438f0a38}}
Finished Retaining in LoaderManager{43945c70 in HistoryFragments{438f0a38}}
Finished Retaining: LoaderInfo{439d8a58 #2 : CursorLoader{439d8ad0}}
onLoadFinished in CursorLoader{439d8ad0 id=2}: CursorWrapperInner{43952be0}
Finished Retaining: LoaderInfo{432dea88 #1 : CursorLoader{4393ad48}}
onLoadFinished in CursorLoader{4393ad48 id=1}: CursorWrapperInner{43952fa8}
And when I come back to the initial orientation, this is the result:
Retaining in LoaderManager{43945c70 in HistoryFragments{438f0a38}}
Retaining: LoaderInfo{439d8a58 #2 : CursorLoader{439d8ad0}}
Retaining: LoaderInfo{432dea88 #1 : CursorLoader{4393ad48}}
Destroying Inactive in LoaderManager{43945c70 in HistoryFragments{438f0a38}}
initLoader in LoaderManager{43945c70 in HistoryFragments{432cab50}}: args=null
Re-using existing loader LoaderInfo{432dea88 #1 : CursorLoader{4393ad48}}
initLoader in LoaderManager{43945c70 in HistoryFragments{432cab50}}: args=null
Re-using existing loader LoaderInfo{439d8a58 #2 : CursorLoader{439d8ad0}}
Starting in LoaderManager{43945c70 in HistoryFragments{432cab50}}
Finished Retaining in LoaderManager{43945c70 in HistoryFragments{432cab50}}
Finished Retaining: LoaderInfo{439d8a58 #2 : CursorLoader{439d8ad0}}
onLoadFinished in CursorLoader{439d8ad0 id=2}: CursorWrapperInner{43952be0}
Finished Retaining: LoaderInfo{432dea88 #1 : CursorLoader{4393ad48}}
onLoadFinished in CursorLoader{4393ad48 id=1}: CursorWrapperInner{43952fa8}
You can use LoaderManager.enableDebugLogging(true)
to debug your loader behavior or you can try to use getSupportLoadermanager()
instead of getLoaderManager()
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