我在TabHost的FrameLayout中有一个TabActivity和一个ListView。这个ListView在我的3个标签中共享。使用处理程序从Internet下载列表中的项目,但是当数据到来时列表不会更新。当我选择另一个选项卡时,列表会自动更新,但我希望能够在下载后看到它正在更新。我已经尝试使ListView,FrameLayout和TabHost无效,但没有任何反应。 notifyDataSetChanged()和notifyDataSetInvalidated()方法也没有帮助。如果我将ListView放在FrameLayout之外,它会按预期工作。这是代码:
<?xml version="1.0" encoding="UTF-8"?>
<TabHost android:id="@android:id/tabhost"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_alignParentTop="true">
<LinearLayout
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<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">
<ListView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/comments_list_lv"
android:layout_width="fill_parent"
android:layout_height="fill_parent" />
</FrameLayout>
</LinearLayout>
public class CommentsActivity extends TabActivity implements Handler.Callback, OnTabChangeListener {
private static final int take = 20;
private Handler handler;
private CommentsListModel model = null;
private ListView listView;
private CommentsListAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.comments_activity);
handler = new Handler(this);
setContentView(R.layout.comments_activity);
listView = (ListView) findViewById(R.id.comments_list_lv);
listView.setTextFilterEnabled(true);
getTabHost().setOnTabChangedListener(this);
buildTabs();
setListView();
requestData();
}
@Override
public boolean handleMessage(Message msg) {
AbstractResponse response = (AbstractResponse) msg.obj;
ResponseStatus status = response.getStatus();
if (status.getResponseCode() == ResponseStatus.OK) {
model = (CommentsListModel) response.getResponseObject();
adapter = new CommentsListAdapter(this, model.getComments());
listView.setAdapter(adapter);
}
return true;
}
@Override
public synchronized void onTabChanged(String tabName) {
if (model != null) {
Resources res = getResources();
CommentsFilter filter = null;
if (tabName.equals(res.getString(R.string.comments_all))) {
filter = new CommentsFilter(model.getComments(), CommentsFilter.ALL);
} else if (tabName.equals(res.getString(R.string.comments_liked))) {
filter = new CommentsFilter(model.getComments(), CommentsFilter.LIKED);
} else if (tabName.equals(res.getString(R.string.comments_disliked))) {
filter = new CommentsFilter(model.getComments(), CommentsFilter.DISLIKED);
}
adapter = new CommentsListAdapter(this, filter.filter());
listView.setAdapter(adapter);
}
}
private void buildTabs() {
Resources res = getResources();
TabHost tabHost = getTabHost();
String tabName = res.getString(R.string.comments_all);
TabHost.TabSpec spec = tabHost.newTabSpec(tabName);
spec.setIndicator(tabName, null);
spec.setContent(R.id.comments_list_lv);
tabHost.addTab(spec);
tabName = res.getString(R.string.comments_liked);
spec = tabHost.newTabSpec(tabName);
spec.setIndicator(tabName, null);
spec.setContent(R.id.comments_list_lv);
tabHost.addTab(spec);
tabName = res.getString(R.string.comments_disliked);
spec = tabHost.newTabSpec(tabName);
spec.setIndicator(tabName, null);
spec.setContent(R.id.comments_list_lv);
tabHost.addTab(spec);
}
private void requestData() {
AbstractRequest request = new CommentsRequest(barcode, 0, take);
request.addListener(handler);
Message msg = new Message();
msg.what = ApplicationActions.ProtocolActions.REQUEST;
msg.obj = request;
msg.setTarget(AsyncRequestController.getInstance().getInboxHandler());
msg.sendToTarget();
}
}
答案 0 :(得分:3)
我解决了这个问题。我只需要在设置适配器后设置listView.setVisibility(View.VISIBLE)。虽然视图未设置为不可见或在XML文件中不存在,但在这种情况下似乎需要设置可见性。