我曾尝试在发布之前搜索SO,但我无法理解如何刷新托管在片段内的ViewPager的内容。 你能帮帮我吗?
感谢您的时间
这是我的代码。 我在其中托管ViewPager的片段活动。它显示不同的小部件和ViewPager显示不同的图像,我从代码中的db“carosello”调用返回的图像列表。当我执行搜索时,我将refresh()方法称为来自托管此片段的主活动的回调,并再次设置所有视图。适用于片段中的所有信息,但不适用于ViewPager:始终显示最早(首次创建)的图像。
public class Page2FamigliaFragment extends Fragment {
//... variable declaration
@Override
public View onCreateView(LayoutInflater inflater,ViewGroup container,Bundle savedInstanceState) {
// fragment not when container null
if (container == null) {
return null;
}
// inflate view from layout
View view = (LinearLayout)inflater.inflate(R.layout.famiglia_page2,container,false);
//retrieve my object from the main view that host this fragment
info = ((MainFamiglia)this.getActivity()).getMyObject();
//run the setup of the view.
setUpMyPage2View(view);
return view;
}
public void setUpMyPage2View(View view)
{
//... inizialization of some other objects and view - i do not show only because is out of topic for this matter
//retrive the image used in the page viewer
carosello = info.getCarosello();
parts = carosello.split(",");
//how many page ??
int i = parts.length / 3;
int resto = parts.length % 3;
int pages = 0;
if (resto!=0) {
pages = i + 1;
} else {
pages = i;
}
List<Fragment> fragments = new ArrayList<Fragment>();
String[] tempArray;
int startIndex = 0;
int endIndex = 3;
if (parts.length <= 3) {
fragments.add(myCarosello.newInstance(parts));
} else {
tempArray = Arrays.copyOfRange(parts, startIndex, endIndex);
for (int p=0; p < pages; p++) {
fragments.add(myCarosello.newInstance(tempArray));
startIndex = endIndex;
endIndex = ((endIndex+3) > parts.length) ? parts.length : (endIndex+3);
tempArray = Arrays.copyOfRange(parts, startIndex, endIndex);
}
}
pageAdapter = new MyPageAdapter(getChildFragmentManager(), fragments);
pager = (ViewPager) view.findViewById(R.id.viewpager);
pager.setAdapter(pageAdapter);
pager.setOnTouchListener(new OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
if(
event.getAction() == MotionEvent.ACTION_DOWN &&
v instanceof ViewGroup
) {
((ViewGroup) v).requestDisallowInterceptTouchEvent(true);
}
return false;
}
});
}
//i call this method from a callback from the main view for refresh this fragment
public void refresh(){
//recupero oggetto dalla activity principale
info = ((MainFamiglia)this.getActivity()).getMyObject();
pager.getAdapter().notifyDataSetChanged();
pager.removeAllViews();
setUpMyPage2View(this.getView());
}
}
这是pageAdapter的类
public class MyPageAdapter extends FragmentPagerAdapter {
// fragments to instantiate in the viewpager
private List<Fragment> fragments;
// constructor
public MyPageAdapter(FragmentManager fm,List<Fragment> fragments) {
super(fm);
this.fragments = fragments;
}
// return access to fragment from position, required override
@Override
public Fragment getItem(int position) {
return this.fragments.get(position);
}
// number of fragments in list, required override
@Override
public int getCount() {
return this.fragments.size();
}
public int getItemPosition(Object object) {
return POSITION_NONE;
}
}
这是pageviewer中imageview的类
public class myCarosello extends Fragment {
public static final String EXTRA_MESSAGE = "EXTRA_MESSAGE";
private int numeroImmagini = 0;
public static final myCarosello newInstance(String[] pictures)
{
myCarosello f = new myCarosello();
Bundle bdl = new Bundle(1);
bdl.putStringArray(EXTRA_MESSAGE, pictures);
f.setArguments(bdl);
return f;
}
@Override
public View onCreateView(LayoutInflater inflater,ViewGroup container,Bundle savedInstanceState) {
String[] pictures = getArguments().getStringArray(EXTRA_MESSAGE);
numeroImmagini = pictures.length;
View view = (LinearLayout)inflater.inflate(R.layout.carosello,container,false);
ImageView imageView1 = (ImageView) view.findViewById(R.id.carosello1);
ImageView imageView2 = (ImageView) view.findViewById(R.id.carosello2);
ImageView imageView3 = (ImageView) view.findViewById(R.id.carosello3);
switch (numeroImmagini) {
case 1:
imageView1.setImageResource(returnImageResource(pictures[0]));
imageView2.setVisibility(View.GONE);
imageView3.setVisibility(View.GONE);
break;
case 2:
imageView1.setImageResource(returnImageResource(pictures[0]));
imageView2.setImageResource(returnImageResource(pictures[1]));
imageView3.setVisibility(View.GONE);
break;
case 3:
imageView1.setImageResource(returnImageResource(pictures[0]));
imageView2.setImageResource(returnImageResource(pictures[1]));
imageView3.setImageResource(returnImageResource(pictures[2]));
break;
}
return view;
}
//return the correct resource name
private int returnImageResource(String image)
{
image = image.replace(" ", "_");
String filenameArray[] = image.split("\\.");
image = "img_" + filenameArray[0].toLowerCase();
int drawableImageId = getActivity().getResources().getIdentifier(image, "drawable", getActivity().getPackageName());
return drawableImageId;
}
}
答案 0 :(得分:32)
感谢this帖子,我已经解决了
将MyPageAdapter extends FragmentPagerAdapter
更改为MyPageAdapter extends FragmentStatePagerAdapter
。
答案 1 :(得分:0)
片段方法中的第一个覆盖
@覆盖
public void setUserVisibleHint(boolean isVisibleToUser) {
super.setUserVisibleHint(isVisibleToUser);
if(isVisibleToUser){
actionView();
}
else{
//no
}
}