我正在加載列表視圖,列出了手機上已安裝的所有應用程序。我希望應用程序在加載列表視圖時顯示不確定的進度條(旋轉的圓形)。ListView加載時無法顯示不確定的ProgressBar
final PackageManager pm = this.getPackageManager();
Intent intent = new Intent(Intent.ACTION_MAIN, null);
intent.addCategory(Intent.CATEGORY_LAUNCHER);
final ArrayList<ResolveInfo> list =
(ArrayList<ResolveInfo>) pm.queryIntentActivities(intent,
PackageManager.PERMISSION_GRANTED);
for (ResolveInfo rInfo : list)
{
Log.i(TAG, ": Installed Applications " + rInfo.activityInfo.
applicationInfo.loadLabel(pm).toString());
}
final ArrayAdapter<ResolveInfo> adapter =
new ArrayAdapter<ResolveInfo>(this, R.layout.list_item, list)
{
@Override
public View getView(int position, View convertView, ViewGroup parent)
{
if (convertView == null)
convertView = LayoutInflater.from(parent.getContext()).
inflate(R.layout.list_item, parent, false);
final String text = list.get(position).activityInfo.
applicationInfo.loadLabel(pm).toString();
((TextView)convertView.findViewById(R.id.text)).setText(text);
final Drawable drawable = list.get(position).activityInfo.applicationInfo.loadIcon(pm);
((ImageView)convertView.findViewById(R.id.image)).setImageDrawable(drawable);
return convertView;
}
};
setListAdapter(adapter);
ListView lv = getListView();
lv.setEmptyView(findViewById(R.id.empty));
lv.setTextFilterEnabled(true);
繼承人的XML:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal" android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ImageView android:id="@+id/image"
android:layout_width="50dp" android:layout_height="50dp" />
<TextView android:id="@+id/text"
android:layout_width="fill_parent" android:layout_height="wrap_content"
android:padding="10dp" android:textSize="16sp" />
<ScrollView
android:id="@+id/empty" android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ProgressBar android:id="@+id/progressBar1" android:layout_width="wrap_content"
android:layout_height="wrap_content"></ProgressBar>
</ScrollView>
</LinearLayout>
不顯示任何內容,而ListView控件加載....我究竟做錯了???
如何加載數據?如何看起來空視圖? – pawelzieba 2011-05-16 21:10:01
你調用lv的列表視圖,但它是XML中的滾動視圖?需要更多解釋 – Blundell 2011-05-16 21:12:11
ListView不是ScrollView。所以,我對你的代碼有點困惑。 – 2011-05-16 21:16:05