我想在视图寻呼机的特定页面中更改图像资源。这就是我所做的。
这是在创建活动...
((PlaceholderFragment)mSectionsPagerAdapter.getItem(0)).updateImage(R.drawable.help1);
((PlaceholderFragment)mSectionsPagerAdapter.getItem(1)).updateImage(R.drawable.help2);
((PlaceholderFragment)mSectionsPagerAdapter.getItem(2)).updateImage(R.drawable.help3);
((PlaceholderFragment)mSectionsPagerAdapter.getItem(3)).updateImage(R.drawable.help4);
这是片段类...
public static class PlaceholderFragment extends Fragment {
/**
* The fragment argument representing the section number for this
* fragment.
*/
private static final String ARG_SECTION_NUMBER = "section_number";
/**
* Returns a new instance of this fragment for the given section
* number.
*/
public static PlaceholderFragment newInstance(int sectionNumber) {
PlaceholderFragment fragment = new PlaceholderFragment();
Bundle args = new Bundle();
args.putInt(ARG_SECTION_NUMBER, sectionNumber);
fragment.setArguments(args);
return fragment;
}
public PlaceholderFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_help, container, false);
ImageView imageView = (ImageView) rootView.findViewById(R.id.imageHelp);
imageView.setImageResource(R.drawable.help4);
return rootView;
}
public void updateImage(int image){
ImageView imageView = (ImageView) getView().findViewById(R.id.imageHelp);
imageView.setImageResource(image);
}
}
但不知何故,它仍然给了我错误空指针异常。我怎么想念?谢谢之前,请帮我:)我在这里呆了大约 2 个小时。
// declare rootView as global variable
public void updateImage(int image){
ImageView imageView = (ImageView) rootView.findViewById(R.id.imageHelp);
imageView.setImageResource(rootView);
}