我一直试图在我的主要 fragmentActivity 上显示一个包含 ListView 的 tabHost。但是我的 listView 根本没有出现。元素正在上传，但视图没有显示它们。
显示 tabHost 的片段
public class GestionListeNote extends Fragment implements OnTabChangeListener {
private static final String TAG = "FragmentTabs";
public static final String TAB_ALL = "All";
public static final String TAB_TOPAY = "To Pay";
public static final String TAB_PAID = "Paid";
public static final String TAB_SEND = "Send";
private View mRoot;
private TabHost mTabHost;
private int mCurrentTab;
@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
mRoot = inflater.inflate(R.layout.tabs_fragment, null);
mTabHost = (TabHost) mRoot.findViewById(android.R.id.tabhost);
setupTabs();
return mRoot;
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
setRetainInstance(true);
mTabHost.setOnTabChangedListener(this);
mTabHost.setCurrentTab(mCurrentTab);
// manually start loading stuff in the first tab
updateTab(TAB_ALL, R.id.tab_1);
}
private void setupTabs() {
mTabHost.setup(); // important!
mTabHost.addTab(newTab(TAB_ALL, R.string.allNotes, R.id.tab_1));
mTabHost.addTab(newTab(TAB_TOPAY, R.string.notesToPay, R.id.tab_2));
mTabHost.addTab(newTab(TAB_PAID, R.string.notesPaid, R.id.tab_3));
mTabHost.addTab(newTab(TAB_SEND, R.string.notesSend, R.id.tab_4));
}
private TabSpec newTab(String tag, int labelId, int tabContentId) {
Log.d(TAG, "buildTab(): tag=" + tag);
View indicator = LayoutInflater.from(getActivity()).inflate(
R.layout.tab,
(ViewGroup) mRoot.findViewById(android.R.id.tabs), false);
((TextView) indicator.findViewById(R.id.text)).setText(labelId);
TabSpec tabSpec = mTabHost.newTabSpec(tag);
tabSpec.setIndicator(indicator);
tabSpec.setContent(tabContentId);
return tabSpec;
}
@Override
public void onTabChanged(String tabId) {
Log.d(TAG, "onTabChanged(): tabId=" + tabId);
if (TAB_ALL.equals(tabId)) {
updateTab(tabId, R.id.tab_1);
mCurrentTab = 0;
Log.d(TAG, "current tab=" + mCurrentTab);
return;
}
if (TAB_TOPAY.equals(tabId)) {
updateTab(tabId, R.id.tab_2);
mCurrentTab = 1;
Log.d(TAG, "current tab=" + mCurrentTab);
return;
}
if (TAB_PAID.equals(tabId)) {
updateTab(tabId, R.id.tab_3);
mCurrentTab = 2;
Log.d(TAG, "current tab=" + mCurrentTab);
return;
}
if (TAB_SEND.equals(tabId)) {
updateTab(tabId, R.id.tab_4);
mCurrentTab = 3;
Log.d(TAG, "current tab=" + mCurrentTab);
return;
}
}
private void updateTab(String tabId, int placeholder) {
FragmentManager fm = getFragmentManager();
if (fm.findFragmentByTag(tabId) == null) {
fm.beginTransaction()
.replace(placeholder, new ListeNotesFragment(tabId), tabId)
.commit();
}
}
那是我的 ListFragment 展示我的元素
public class ListeNotesFragment extends ListFragment implements
LoaderCallbacks<Void> {
private static final String TAG = "FragmentTabs";
private String mTag;
private MyAdapter mAdapter;
private ArrayList<String> mItems;
private LayoutInflater mInflater;
private int mTotal;
private int mPosition;
private static final String[] All = { "Lorem", "ipsum", "dolor", "sit",
"amet", "consectetur", "adipiscing", "elit", "Fusce", "pharetra",
"luctus", "sodales" };
private static final String[] ToPay = { "I", "II", "III", "IV", "V",
"VI", "VII", "VIII", "IX", "X", "XI", "XII", "XIII", "XIV", "XV" };
private static final String[] Paid = { "Test" };
private static final String[] Send = { "Test" };
private static final int SLEEP = 1000;
private final int allBarColor = R.color.all_bar;
private final int topayBarColor = R.color.topay_bar;
private final int paidBarColor = R.color.paid_bar;
private final int sendBarColor = R.color.send_bar;
public ListeNotesFragment() {
}
public ListeNotesFragment(String tag) {
mTag = tag;
mTotal = GestionListeNote.TAB_ALL.equals(mTag) ? All.length
: (GestionListeNote.TAB_TOPAY.equals(mTag) ? ToPay.length
: (GestionListeNote.TAB_PAID.equals(mTag) ? Paid.length
: Send.length ) );
Log.d(TAG, "mTotal =" + mTotal);
Log.d(TAG, "Constructor: tag=" + tag);
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
// this is really important in order to save the state across screen
// configuration changes for example
setRetainInstance(true);
mInflater = LayoutInflater.from(getActivity());
// you only need to instantiate these the first time your fragment is
// created; then, the method above will do the rest
if (mAdapter == null) {
mItems = new ArrayList<String>();
mAdapter = new MyAdapter(getActivity(), mItems);
}
getListView().setAdapter(mAdapter);
// initiate the loader to do the background work
getLoaderManager().initLoader(0, null, this);
}
@Override
public Loader<Void> onCreateLoader(int id, Bundle args) {
AsyncTaskLoader<Void> loader = new AsyncTaskLoader<Void>(getActivity()) {
@Override
public Void loadInBackground() {
try {
// simulate some time consuming operation going on in the
// background
Thread.sleep(SLEEP);
} catch (InterruptedException e) {
}
return null;
}
};
// somehow the AsyncTaskLoader doesn't want to start its job without
// calling this method
loader.forceLoad();
Log.d(TAG, "Stop sleep");
return loader;
}
@Override
public void onLoadFinished(Loader<Void> loader, Void result) {
// add the new item and let the adapter know in order to refresh the
// views
mItems.add(GestionListeNote.TAB_ALL.equals(mTag) ? All[mPosition]
: (GestionListeNote.TAB_TOPAY.equals(mTag) ? ToPay[mPosition]
: (GestionListeNote.TAB_PAID.equals(mTag) ? Paid[mPosition]
: Send[mPosition]) ) );
mAdapter.notifyDataSetChanged();
Log.d(TAG, "item =" + mItems.get(mPosition));
// advance in your list with one step
mPosition++;
if (mPosition < mTotal - 1) {
getLoaderManager().restartLoader(0, null, this);
Log.d(TAG, "onLoadFinished(): loading next...");
} else {
Log.d(TAG, "onLoadFinished(): done loading!");
}
}
@Override
public void onLoaderReset(Loader<Void> loader) {
}
private class MyAdapter extends ArrayAdapter<String> {
public MyAdapter(Context context, List<String> objects) {
super(context, R.layout.list_item, R.id.text, objects);
Log.d(TAG, "affiche contenu");
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View view = convertView;
Wrapper wrapper;
Log.d(TAG, "affiche vue");
if (view == null) {
view = mInflater.inflate(R.layout.list_item, null);
wrapper = new Wrapper(view);
view.setTag(wrapper);
} else {
wrapper = (Wrapper) view.getTag();
}
wrapper.getTextView().setText(getItem(position));
wrapper.getBar().setBackgroundColor(
GestionListeNote.TAB_ALL.equals(mTag) ? getResources().getColor(allBarColor)
: (GestionListeNote.TAB_TOPAY.equals(mTag) ? getResources().getColor(topayBarColor)
: (GestionListeNote.TAB_PAID.equals(mTag) ? getResources().getColor(paidBarColor)
:getResources().getColor(sendBarColor)) ) );
return view;
}
}
// use an wrapper (or view holder) object to limit calling the
// findViewById() method, which parses the entire structure of your
// XML in search for the ID of your view
private class Wrapper {
private final View mRoot;
private TextView mText;
private View mBar;
public Wrapper(View root) {
mRoot = root;
Log.d(TAG, "initialise view");
}
public TextView getTextView() {
if (mText == null) {
mText = (TextView) mRoot.findViewById(R.id.text);
Log.d(TAG, "initialise TextView");
}
Log.d(TAG, "initialise view");
return mText;
}
public View getBar() {
if (mBar == null) {
mBar = mRoot.findViewById(R.id.bar);
Log.d(TAG, "initialise view");
}
Log.d(TAG, "initialise view");
return mBar;
}
}
在xml下面
主要的
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<fragment
android:layout_width="match_parent"
android:layout_height="wrap_content"
class="org.newnote.android.AddNoteButton" />
<fragment
android:id="@+id/tabs_fragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
class="org.newnote.android.GestionListeNote" />
liste_item
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="@dimen/list_item_height"
android:gravity="left|center_vertical">
<View
android:id="@+id/bar"
android:layout_width="10dp"
android:layout_height="fill_parent" />
<TextView
android:id="@+id/text"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingLeft="10dp"
android:gravity="center" />
tabs_fragment
<TabHost xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@android:id/tabhost"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#EFEFEF" >
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TabWidget
android:id="@android:id/tabs"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<FrameLayout
android:id="@android:id/tabcontent"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<FrameLayout
android:id="@+id/tab_1"
android:layout_width="fill_parent"
android:layout_height="fill_parent" />
<FrameLayout
android:id="@+id/tab_2"
android:layout_width="fill_parent"
android:layout_height="fill_parent" />
<FrameLayout
android:id="@+id/tab_3"
android:layout_width="fill_parent"
android:layout_height="fill_parent" />
<FrameLayout
android:id="@+id/tab_4"
android:layout_width="fill_parent"
android:layout_height="fill_parent" />
</FrameLayout>
</LinearLayout>
标签
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="80dp"
android:layout_height="@dimen/tab_height"
android:gravity="center"
android:padding="@dimen/tab_padding"
android:background="@drawable/tab_selector">
<TextView
android:id="@+id/text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center"
android:textSize="@dimen/text_small"
android:textStyle="bold"
android:textColor="@drawable/tab_text_selector" />
我不明白为什么我的片段不显示元素
希望你能帮助我。