我想在我的fragments中显示3 Activity，并在任何json中加载来自 fragments 的数据！我希望将每个json数据显示为一个片段，但在我的应用程序中首先加载3 fragments json 数据，然后输入应用程序。
例如：首次进入应用程序时加载所有fragments数据，但我想在显示此片段时加载数据（在fragment上轻扫 ）。
片段1代码：
public class free_fragment extends Fragment {
private RecyclerView mRecyclerView;
private free_recycler_adapter mAdapter;
private RecyclerView.LayoutManager mLayoutManager;
private List<DataModel> dataModels = new ArrayList<DataModel>();
private Context context;
@Override
public View onCreateView(LayoutInflater inflater,
ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_free_layout, container, false);
context = getContext();
LoadData();
///----- RecyclerView -----
mRecyclerView = (RecyclerView) view.findViewById(R.id.pdf_RecyclerView);
mRecyclerView.setHasFixedSize(true);
mRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
mAdapter = new free_recycler_adapter(context, dataModels);
mRecyclerView.setAdapter(mAdapter);
return view;
}
@Subscribe
public void onEvent(MyEvent event) {
List<DataModel> dataModels = event.getInfoModels();
if (event.fragmentTag.equals("forfragment1")) {
mAdapter.add(dataModels);
mAdapter.notifyDataSetChanged();
}
}
private void LoadData() {
freeDataInfo dataInfo = new freeDataInfo();
// here getMainDataInfo() should return the server response
dataInfo.getFreeDataInfo(context);
}
@Override
public void onResume() {
super.onResume();
EventBus.getDefault().register(this);
}
@Override
public void onPause() {
EventBus.getDefault().unregister(this);
super.onPause();
}
}
片段1 AsyncTask代码：
public class freeDataInfo {
private Context mContext;
private String ServerAddress = freeServer_IP.getFreeIP();
public void getFreeDataInfo(Context context) {
mContext = context;
new getInfo().execute(ServerAddress + "limit=10");
}
private class getInfo extends AsyncTask<String, Void, String> {
EventBus bus = EventBus.getDefault();
private String ou_response;
private List<DataModel> infoModels = new ArrayList<>();
private ProgressDialog dialog;
@Override
protected void onPreExecute() {
//CustomProcessDialog.createAndShow(mContext);
dialog = new ProgressDialog(mContext);
this.dialog.setMessage("شکیبا باشید...");
this.dialog.show();
}
@Override
protected String doInBackground(String... params) {
OkHttpClient client = new OkHttpClient();
//String url = (String) params[0];
Request request = new Request.Builder()
.url(ServerAddress + "limit=10")
.cacheControl(CacheControl.FORCE_NETWORK)
.build();
Response response;
try {
response = client.newCall(request).execute();
ou_response = response.body().string();
response.body().close();
if (ou_response != null) {
try {
JSONObject postObj = new JSONObject(ou_response);
JSONArray postsArray = postObj.optJSONArray("result");
for (int i = 0; i <= postsArray.length(); i++) {
JSONObject postObject = (JSONObject) postsArray.get(i);
int id = postObject.getInt("id");
Log.d("id", String.valueOf(id));
String title = postObject.getString("title");
String description = postObject.getString("description");
String image = postObject.getString("image");
String category = postObject.getString("categoryName");
String date = postObject.getString("publishDate");
Log.d("Data", "Post ID: " + id);
Log.d("Data", "Post title: " + title);
Log.d("Data", "Post image: " + image);
Log.d("Data", "---------------------------------");
//Use the title and id as per your requirement
infoModels.add(new DataModel(id, title, description, category, date, image));
}
} catch (JSONException e) {
e.printStackTrace();
Log.e("error", String.valueOf(e));
}
}
} catch (IOException e) {
e.printStackTrace();
Log.e("error2", String.valueOf(e));
}
return ou_response;
}
@Override
protected void onPostExecute(String result) {
//CustomProcessDialog.dissmis();
//Stop Progress
if (dialog.isShowing()) {
dialog.dismiss();
}
if (result != null) {
bus.post(new MyEvent("forfragment1", infoModels));
} else {
Toast.makeText(mContext, "Empty", Toast.LENGTH_SHORT).show();
}
}
}
}
片段2代码：
public class paid_fragment extends Fragment {
private RecyclerView mRecyclerView;
private paid_recycler_adapter mAdapter;
private RecyclerView.LayoutManager mLayoutManager;
private List<DataModel> dataModels = new ArrayList<DataModel>();
private Context context;
@Override
public View onCreateView(LayoutInflater inflater,
ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_paid_layout, container, false);
context = getContext();
/* if (!EventBus.getDefault().isRegistered(this)) {
EventBus.getDefault().register(this);
}*/
LoadData();
///----- RecyclerView -----
mRecyclerView = (RecyclerView) view.findViewById(R.id.voice_RecyclerView);
mRecyclerView.setHasFixedSize(true);
mRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
mAdapter = new paid_recycler_adapter(context, dataModels);
mRecyclerView.setAdapter(mAdapter);
return view;
}
@Subscribe
public void onEvent(MyEvent event) {
List<DataModel> dataModels = event.getInfoModels();
/* if (dataModels.size() > 0) {
dataModels.remove(dataModels.size() - 1);
mAdapter.notifyItemRemoved(dataModels.size());
//mAdapter.setLoaded();
}*/
if (event.fragmentTag.equals("forfragment2")) {
mAdapter.add(dataModels);
mAdapter.notifyDataSetChanged();
}
}
private void LoadData() {
paidDataInfo dataInfo = new paidDataInfo();
// here getMainDataInfo() should return the server response
dataInfo.getPaidDataInfo(context);
}
@Override
public void onResume() {
super.onResume();
EventBus.getDefault().register(this);
}
@Override
public void onPause() {
EventBus.getDefault().unregister(this);
super.onPause();
}
}
片段2 AsyncTask代码：
public class paidDataInfo {
private Context mContext;
private String ServerAddress = paidServer_IP.getPaidIP();
public void getPaidDataInfo(Context context) {
mContext = context;
new getInfo().execute(ServerAddress + "limit=10");
}
private class getInfo extends AsyncTask<String, Void, String> {
EventBus bus = EventBus.getDefault();
private String ou_response;
private List<DataModel> infoModels = new ArrayList<>();
private ProgressDialog dialog;
@Override
protected void onPreExecute() {
//CustomProcessDialog.createAndShow(mContext);
//infoModels = new ArrayList<>();
// Initiate Progress
dialog = new ProgressDialog(mContext);
this.dialog.setMessage("شکیبا باشید...");
this.dialog.show();
infoModels.clear();
}
@Override
protected String doInBackground(String... params) {
OkHttpClient client = new OkHttpClient();
//String url = (String) params[0];
Request request = new Request.Builder()
.url(ServerAddress + "limit=10")
.cacheControl(CacheControl.FORCE_NETWORK)
.build();
Response response;
try {
response = client.newCall(request).execute();
ou_response = response.body().string();
response.body().close();
if (ou_response != null) {
try {
JSONObject postObj = new JSONObject(ou_response);
JSONArray postsArray = postObj.optJSONArray("result");
infoModels = new ArrayList<>();
for (int i = 0; i <= postsArray.length(); i++) {
JSONObject postObject = (JSONObject) postsArray.get(i);
int id = postObject.getInt("id");
Log.d("id", String.valueOf(id));
String title = postObject.getString("title");
String description = postObject.getString("full_description");
String image = postObject.getString("image");
String category = postObject.getString("categoryName");
String date = postObject.getString("publishDate");
Log.d("Data", "Post ID: " + id);
Log.d("Data", "Post title: " + title);
Log.d("Data", "Post Desc: " + description);
Log.d("Data", "Post image: " + image);
Log.d("Data", "---------------------------------");
//Use the title and id as per your requirement
infoModels.add(new DataModel(id, title, description, category, date, image));
}
} catch (JSONException e) {
e.printStackTrace();
Log.e("error", String.valueOf(e));
}
}
} catch (IOException e) {
e.printStackTrace();
Log.e("error2", String.valueOf(e));
}
return ou_response;
}
@Override
protected void onPostExecute(String result) {
//Stop Progress
if (dialog.isShowing()) {
dialog.dismiss();
}
//CustomProcessDialog.dissmis();
if (result != null) {
bus.post(new MyEvent("forfragment2", infoModels));
} else {
Toast.makeText(mContext, "Empty", Toast.LENGTH_SHORT).show();
}
}
}
}
主要活动代码：
public class Main_Page extends AppCompatActivity {
private CollapsingToolbarLayout mCollapsingToolbarLayout;
private Toolbar toolbar;
private TabLayout tabLayout;
private ViewPager viewPager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main__page);
mCollapsingToolbarLayout = (CollapsingToolbarLayout) findViewById(R.id.collapsing_toolbar_layout);
//mCollapsingToolbarLayout.setTitle(getResources().getString(R.string.app_name));
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
//getSupportActionBar().setDisplayHomeAsUpEnabled(true);
viewPager = (ViewPager) findViewById(R.id.viewpager);
setupViewPager(viewPager);
tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(viewPager);
setupTabIcons();
}
/**
* Adding custom view to tab
*/
private void setupTabIcons() {
TextView tabOne = (TextView) LayoutInflater.from(this).inflate(R.layout.custom_tab, null);
tabOne.setText(R.string.free_fragment_title);
tabOne.setCompoundDrawablesWithIntrinsicBounds(0, R.drawable.ic_download_image, 0, 0);
tabLayout.getTabAt(0).setCustomView(tabOne);
TextView tabTwo = (TextView) LayoutInflater.from(this).inflate(R.layout.custom_tab, null);
tabTwo.setText(R.string.paid_fragment_title);
tabTwo.setCompoundDrawablesWithIntrinsicBounds(0, R.drawable.ic_paid_download_image, 0, 0);
tabLayout.getTabAt(1).setCustomView(tabTwo);
TextView tabThree = (TextView) LayoutInflater.from(this).inflate(R.layout.custom_tab, null);
tabThree.setText(R.string.pdf_fragment_title);
tabThree.setCompoundDrawablesWithIntrinsicBounds(0, R.drawable.ic_pdf_icon, 0, 0);
tabLayout.getTabAt(2).setCustomView(tabThree);
}
/**
* Adding fragments to ViewPager
* @param viewPager
*/
private void setupViewPager(ViewPager viewPager) {
ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager());
adapter.addFrag(new free_fragment(), "رایگان ها");
adapter.addFrag(new paid_fragment(), "پرداختی ها");
adapter.addFrag(new pdf_fragment(), "مقالات");
viewPager.setAdapter(adapter);
}
class ViewPagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public ViewPagerAdapter(FragmentManager manager) {
super(manager);
}
@Override
public Fragment getItem(int position) {
return mFragmentList.get(position);
}
@Override
public int getCount() {
return mFragmentList.size();
}
public void addFrag(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
@Override
public CharSequence getPageTitle(int position) {
return mFragmentTitleList.get(position);
}
}
我如何解决这个问题？加载片段数据只显示片段？谢谢所有＆lt; 3
答案 0 :(得分：1)
当片段对用户可见时，会调用一个回调方法。您可以在此方法中触发loadData（）。有一个布尔值，告诉你数据是否已被提取。请参考以下代码行：
在您的片段代码中添加以下方法。
@Override
public void setUserVisibleHint(boolean isVisibleToUser) {
mIsVisibleToUser = isVisibleToUser;
if (isVisibleToUser && !isDataFetched && getContext() != null) {
context = getContext();
LoadData(); //Remove this call from onCreateView
}
}
在onEvent方法中进行以下更改。
@Subscribe
public void onEvent(MyEvent event) {
List<DataModel> dataModels = event.getInfoModels();
if (event.fragmentTag.equals("forfragment1")) {
mAdapter.add(dataModels);
isDataFetched = true;
mAdapter.notifyDataSetChanged();
}
}
在片段代码中添加实例变量。
private boolean isDataFetched;
private boolean mIsVisibleToUser;
最后修改OnCreateView（）
if(mIsVisibleToUser)
LoadData();
确保对这两个片段进行这些更改。