我卡住试图重新加载ListView
内ListFragment
。刷新是通过我在FragmentDialog
中创建的侦听器调用的。 reloadItems方法已正确调用,并且我已验证项目列表在变量中已正确更新。重新加载列表视图从内联类
这似乎是一个简单的事情要做,但我卡住了。 ListView从来没有实际更新,但我相信它与使用的Context
有关。
onClick
通过使用属性设置的ListView
行的按钮调用。
解决方案 的问题是,我的选项卡适配器getItem(...)
被unexpectantly再次呼吁创建时AlertDialog
被而且由于我可怜的代码,它重新实例化的标签,并刷新从未发生过的可见片段。 (请参见最后的原始代码)
一旦发现此问题(请参阅接受的答案),我可以通过重新修改代码选项卡适配器来修复它以维护引用。这是我的工作选项卡适配器,适用于ViewPager
以防万一对任何人有帮助。
public class TabsAdapter extends FragmentPagerAdapter implements ActionBar.TabListener, ViewPager.OnPageChangeListener {
private final Context mContext;
private final ActionBar mActionBar;
private final ViewPager mViewPager;
private final ArrayList<TabInfo> mTabs = new ArrayList<TabInfo>();
private ArrayList<Fragment> mFragments = new ArrayList<Fragment>();
static final class TabInfo {
private final Class<?> mClass;
private final Bundle mArgs;
TabInfo(Class<?> _class, Bundle _args) {
mClass = _class;
mArgs = _args;
}
public String getClassName() {
return mClass.getName();
}
public Bundle getArgs() {
return mArgs;
}
}
public TabsAdapter(Activity activity, ViewPager pager) {
super(activity.getFragmentManager());
mContext = activity;
mActionBar = activity.getActionBar();
mViewPager = pager;
mViewPager.setAdapter(this);
mViewPager.setOnPageChangeListener(this);
}
public void addTab(ActionBar.Tab tab, Class<?> clss, Bundle args) {
TabInfo info = new TabInfo(clss, args);
tab.setTag(info);
tab.setTabListener(this);
mTabs.add(info);
mActionBar.addTab(tab);
Fragment fragment = Fragment.instantiate(mContext, info.getClassName(), info.getArgs());
mFragments.add(fragment);
notifyDataSetChanged();
}
@Override
public int getCount() {
return mTabs.size();
}
@Override
public Fragment getItem(int position) {
return mFragments.get(position);
}
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
public void onPageSelected(int position) {
mActionBar.setSelectedNavigationItem(position);
}
public void onPageScrollStateChanged(int state) {
}
public void onTabSelected(Tab tab, FragmentTransaction ft) {
Object tag = tab.getTag();
for (int i = 0; i < mTabs.size(); i++) {
if (mTabs.get(i) == tag) {
mViewPager.setCurrentItem(i);
}
}
}
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
}
public void onTabReselected(Tab tab, FragmentTransaction ft) {
}
}
的解决方案最终
活动
public class MyActivity extends Activity {
// unrelated code removed
public void onClick(View v) {
// onClick is called via a button on a list item
MyFragment sf = (MyFragment)mTabsAdapter.getItem(0);
sf.myClick(v, getFragmentManager());
}
}
MyFragment
public class MyFragment extends ListFragment {
static final String TAG = "StatusFragment";
private ArrayList<MyObject> mItems = null;
AlarmDataSource datasource;
StatusAdapter mAdapter;
public void reloadItems(Context context) {
Log.d(TAG, "reloadItems");
datasource = new MyObjectDataSource(context);
datasource.open();
mItems = new ArrayList<MyObject>();
ArrayList<MyObject> active = (ArrayList<MyObject>)datasource.getAllEnabled();
for (int i = 0; i < active.size(); i++) {
MyObject next = active.get(i);
mItems.add(next);
}
mAdapter = new StatusAdapter(
context,
R.layout.status_list_item,
mItems);
// set a breakpoint and this is called when called from
// statusOptionDialogClose below. Here mAdapter DOES HAVE updated items
// inside. However getView within the adaper is NOT called
setListAdapter(mAdapter);
datasource.close();
}
public void myClick(View v, FragmentManager manager) {
StatusOptionDialog sod = StatusOptionDialog.newInstance(v.getContext());
sod.setStatusOptionDialogListener(new StatusOptionDialogListener() {
public void statusOptionDialogClose(Context context) {
// this is correctly called when dialog closed
// context is the same as sent in with newInstance above.
reloadItems(context);
}
});
sod.show(manager, "StatusOptionDialog");
}
}
任何人看到什么歪?我尝试了很多不同的方式,但没有任何工作。
注意我也试过mAdapter.notifyDataSetChanged()
更新时,也不起作用。今天晚些时候我会尝试逐步浏览Android SDK代码,看看是否可以在那里精确定位数据,以防数据没有进入适配器或有些奇怪。
更新我追查了更多的问题。看起来在setListItem(mAdapter)
与mAdapter成功更新了项目后,不会调用适配器getView(...)
。
更新#2我已经发布reloadItems(...)
函数,我已经蒸馏成最简单的代码有问题。 setListAdapter(...)
使用已更新项目的更新适配器调用。但是getView(...)
永远不会调用reloadItems(...)
通过statusOptionDialogClose(...)
调用如果我杀死应用程序并重新启动它,ListView显示更新的数据。只是在再次调用reloadItem时不刷新。
适配器
public class StatusAdapter extends ArrayAdapter<MyObject> {
private Context mContext;
private int mRes;
private ArrayList<MyObject> mItems;
public StatusAdapter(Context context, int textViewResourceId, ArrayList<MyObject> items) {
super(context, textViewResourceId, items);
this.mItems = items;
this.mRes = textViewResourceId;
this.mContext = context;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View v = convertView;
if (v == null) {
LayoutInflater vi = (LayoutInflater)mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
v = vi.inflate(mRes, null);
}
Alarm a = mItems.get(position);
if (a != null) {
// fills out list item
}
return v;
}
@Override
public int getCount() {
return mItems.size();
}
public void setNewList(ArrayList<Alarm> items) {
this.mItems = items;
}
}
选项卡适配器这是用来使ViewPager
和选项卡。
public class TabsAdapter extends FragmentPagerAdapter implements
ActionBar.TabListener, ViewPager.OnPageChangeListener {
private final Context mContext;
private final ActionBar mActionBar;
private final ViewPager mViewPager;
private final ArrayList<TabInfo> mTabs = new ArrayList<TabInfo>();
static final class TabInfo {
private final Class<?> clss;
private final Bundle args;
TabInfo(Class<?> _class, Bundle _args) {
clss = _class;
args = _args;
}
}
public TabsAdapter(Activity activity, ViewPager pager) {
super(activity.getFragmentManager());
mContext = activity;
mActionBar = activity.getActionBar();
mViewPager = pager;
mViewPager.setAdapter(this);
mViewPager.setOnPageChangeListener(this);
}
public void addTab(ActionBar.Tab tab, Class<?> clss, Bundle args) {
TabInfo info = new TabInfo(clss, args);
tab.setTag(info);
tab.setTabListener(this);
mTabs.add(info);
mActionBar.addTab(tab);
notifyDataSetChanged();
}
@Override
public int getCount() {
return mTabs.size();
}
@Override
public Fragment getItem(int position) {
TabInfo info = mTabs.get(position);
return Fragment.instantiate(mContext, info.clss.getName(), info.args);
}
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
public void onPageSelected(int position) {
mActionBar.setSelectedNavigationItem(position);
}
public void onPageScrollStateChanged(int state) {
}
public void onTabSelected(Tab tab, FragmentTransaction ft) {
Object tag = tab.getTag();
for (int i = 0; i < mTabs.size(); i++) {
if (mTabs.get(i) == tag) {
mViewPager.setCurrentItem(i);
}
}
}
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
}
public void onTabReselected(Tab tab, FragmentTransaction ft) {
}
}
谢谢你的回复。我发布了我使用的选项卡适配器,以防使用它。我不确定getItem(...)是否正确实现。我在那里放置了一个断点,它被称为超过预期。 – Kirk 2012-08-13 15:44:41
你说得对。该选项卡适配器正在重新创建片段。我重写了它,并修复了它。哇,花了很多时间来解决这个问题。总是有些愚蠢的东西阻止我。 – Kirk 2012-08-13 16:30:07
很高兴帮助!对于它的价值,我可以告诉你,我有这种怀疑,因为我在不同时间犯了同样的错误:) – Joe 2012-08-13 16:52:51