AM在Android Fragments中不太好用。我们需要一个合适的解决方案来解决我的问题在母亲活动中我是片段A，B，C。每一个片段都在接连不断。首先显示一个片段，在一些用户输入之后，我们用片段B替换它，并且片段A被堆叠。 B完成后，我们用C片段替换它，B在A之后堆叠。我可以回到上一个片段来编辑数据，这样我们就可以保存用户输入。
但是当我回到Fragments时，我总能得到所有数据，但只能更新Fragment A UI视图。我无法更新片段B和C中的任何ui视图。
不同部分的代码隐藏
abid hasan：获取当前对象进行更新
城市currentCity = cityManager.getCurrentCity（）;
updateViews(currentCity);
检查此对象的数据并更新视图。
public static void updateViews(City currentCity){
Log.d(TAG , "updating views for city... "+currentCity.getCityName());
if (currentCity.getCityAccommodations().size() > 0 || currentCity.getCityLocations().size() > 0 || currentCity.getHotels().size() > 0) {
viewModifyLayoutHotels.setVisibility(View.VISIBLE);
deSelectAccommodationRadioButton.setChecked(false);
} else {
viewModifyLayoutHotels.setVisibility(View.GONE);
}
if (currentCity.cityFlights.size() > 0) {
viewModifyLayoutFlights.setVisibility(View.VISIBLE);
deSelectFlyRadioButton.setChecked(false);
} else {
viewModifyLayoutFlights.setVisibility(View.GONE);
}
if(currentCity.getFlightClass().equals("")){
viewModifyLayoutFlights.setVisibility(View.VISIBLE);
deSelectFlyRadioButton.setChecked(false);
}else {
viewModifyLayoutFlights.setVisibility(View.GONE);
}
if (currentCity.getActivities().size() > 0) {
viewModifyLayoutActivities.setVisibility(View.VISIBLE);
deSelectActivityRadioButton.setChecked(false);
} else {
viewModifyLayoutActivities.setVisibility(View.GONE);
}
}
来自后继片段的onDestroy（）方法的反压事件，并从经理和更新视图中获取该对象
public static void updateViews(City currentCity){
Log.d(TAG , "updating views for city... "+currentCity.getCityName());
if (currentCity.getCityAccommodations().size() > 0 || currentCity.getCityLocations().size() > 0 || currentCity.getHotels().size() > 0) {
viewModifyLayoutHotels.setVisibility(View.VISIBLE);
deSelectAccommodationRadioButton.setChecked(false);
} else {
viewModifyLayoutHotels.setVisibility(View.GONE);
}
if (currentCity.cityFlights.size() > 0) {
viewModifyLayoutFlights.setVisibility(View.VISIBLE);
deSelectFlyRadioButton.setChecked(false);
} else {
viewModifyLayoutFlights.setVisibility(View.GONE);
}
if(currentCity.getFlightClass().equals("")){
viewModifyLayoutFlights.setVisibility(View.VISIBLE);
deSelectFlyRadioButton.setChecked(false);
}else {
viewModifyLayoutFlights.setVisibility(View.GONE);
}
if (currentCity.getActivities().size() > 0) {
viewModifyLayoutActivities.setVisibility(View.VISIBLE);
deSelectActivityRadioButton.setChecked(false);
} else {
viewModifyLayoutActivities.setVisibility(View.GONE);
}
}
我将这些视图从onStart（）方法重置为初始状态
@Override
public void onStart() {
Log.d(MakeATripStepFourFragment.TAG , "calling onStart from "+TAG);
MakeATripFragmentFirstTime.destinationTextView.setText("Select experts for your trip");
resetCityPreferencesViews();
super.onStart();
}
public static void resetCityPreferencesViews() {
MakeATripStepFourFragment.deSelectFlyRadioButton.setChecked(true);
MakeATripStepFourFragment.selectFlyRadioButton.setChecked(false);
MakeATripStepFourFragment.deSelectAccommodationRadioButton.setChecked(true);
MakeATripStepFourFragment.selectAccommodationRadioButton.setChecked(false);
MakeATripStepFourFragment.deSelectActivityRadioButton.setChecked(true);
MakeATripStepFourFragment.selectActivityRadioButton.setChecked(false);
MakeATripStepFourFragment.viewModifyLayoutFlights.setVisibility(View.GONE);
MakeATripStepFourFragment.viewModifyLayoutHotels.setVisibility(View.GONE);
MakeATripStepFourFragment.viewModifyLayoutActivities.setVisibility(View.GONE);
}
那个城市的UI没有更新我使用LocalBroadcast调用来分离UI线程更新
if (!childFragment.onBackPressed()) {
// child Fragment was unable to handle the task
// It could happen when the child Fragment is last last leaf of a chain
// removing the child Fragment from stack
Log.d(MakeATripStepFourFragment.TAG , "this fragment.. "+childFragment.getClass().getSimpleName());
if(childFragment instanceof MakeATripStepFourFragment){
Log.d(MakeATripStepFourFragment.TAG ,"lets try it out");
if (cityManager.hasNextCity()) {
City currentCity = cityManager.getNextCity();
MakeATripFragmentFirstTime.destinationTextView.setText(currentCity.getCityName());
Log.d(MakeATripStepFourFragment.TAG, "updating radioButton with city.. "+currentCity.getCityName());
Intent intent = new Intent("update_radio-button");
intent.putExtra(MakeATripStepFourFragment.TAG,currentCity);
LocalBroadcastManager.getInstance(((MakeATripStepFourFragment) childFragment).getActivity()).sendBroadcast(intent);
}
}
childFragmentManager.popBackStackImmediate();
}
// either this Fragment or its child handled the task
// either way we are successful and done here
return true;
}
并在广播接收器中调用updateViews（）方法
private BroadcastReceiver updatePreferences = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
City currentCity = (City) intent.getSerializableExtra(TAG);
Log.d(TAG , "recived call with city..."+currentCity.getCityName());
ExpertSelectorFragment.resetCityPreferencesViews();
updateViews(currentCity);
}
};
我必须知道的解决方案是什么。请完美的建议
点击按钮，循环浏览城市对象并为其添加片段，如果所有城市遍历完成，则进入下一个片段
case R.id.next_fragment_destination_button:
if (!cityManager.hasNextCity()) {
Log.d("status = ", "all city explored : " + cityManager.currentCityIndex);
cityManager.currentCityIndex = 0;
/*LocalBroadcastManager.getInstance(mActivity).unregisterReceiver(messageReceiver);
LocalBroadcastManager.getInstance(mActivity).unregisterReceiver(accomodationAllPreferenceReciver);
LocalBroadcastManager.getInstance(mActivity).unregisterReceiver(activitiesForCityPreferenceReciver);
LocalBroadcastManager.getInstance(mActivity).unregisterReceiver(updatePreferences);*/
setDataToGetExperts(cityManager.getAllCities().size());
} else {
Log.d("status = ", "going to next : " + cityManager.currentCityIndex);
Log.d(TAG, "current city size " + cityManager.getCurrentCity().toString());
cityManager.getNextCity();
//we have a next city
MakeATripStepFourFragment fragment = MakeATripStepFourFragment.newInstance(0);
FragmentTransaction transaction = getChildFragmentManager().beginTransaction();
// Store the Fragment in stack
transaction.addToBackStack(null);
transaction.replace(R.id.fragment_holder, fragment ,TAG);
transaction.commit();
}
break;