父activity布局
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".LockerCodeActivity" >
<LinearLayout
android:id="@+id/fragment_container"
android:layout_width="match_parent"
android:layout_height="match_parent">
</LinearLayout>
<ProgressBar
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:id="@+id/ctrlActivityIndicator"
android:indeterminateOnly="true"
android:keepScreenOn="false"
/>
<TextView
android:id="@+id/tv_results"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:text="" />
</RelativeLayout>
在父activity的onCreate方法中的fragment
FragmentManager fragmentManager = getFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
Fragment scannerFragment = new ScanFragment();
fragmentTransaction.add(R.id.fragment_container, scannerFragment);
fragmentTransaction.commit();
大概差不多就這樣。現在我怎麼樣才能隱藏掉進度條?我現在是這樣做的。
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_scan, container, false);
ProgressBar progressBar = (ProgressBar) view.findViewById(R.id.ctrlActivityIndicator);
progressBar.setVisibility(View.INVISIBLE);
return view;
}
但是我得到了一個空指針異常
這樣:
fragment裡面:
onAttach(Activity activity) {
ProgressBar progressBar = (ProgressBar) activity.findViewById(R.id.ctrlActivityIndicator);
progressBar.setVisibility(View.INVISIBLE);
}