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Button in fragment could not be reached

I am new in android programming. Just trying to use fragment. I am using the following code :
public class SimpleFragActivity extends ActionBarActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_simple_fragment);
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment()).commit();
}
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_simple,
container, false);
Button btnClickMeBlue = (Button)rootView.findViewById(R.id.btnsimplefrag);
return rootView;
}
}
}
XML code:
<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"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.example.framentexample.SimpleFragActivity$PlaceholderFragment" >
<ImageView
android:id="#+id/imageView1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentTop="true"
android:scale="centercrop"
android:src="#drawable/royal_enfield_blue" />
<Button
android:id="#+id/btnsimplefrag"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBottom="#+id/imageView1"
android:layout_centerHorizontal="true"
android:layout_marginBottom="42dp"
android:text="Click Me Blue" />
</RelativeLayout>
but it throws an error saying
btnsimplefrag could not be resolved
Can anybody help me out? I tried many things and could not resolve the issue.

Accessing parent Fragment layout from child Fragment

Good day to all. I can't figure out how to access parent Fragment layout from child Fragment. Let's say I have main activity with tabs defined in ActionBar. Each Tab is Fragment. Now in one of those tabs I want to use tabs again (sticked to bottom this time). I'm able to create needed layout using classic TabHost. Each of these sub-tabs will be operated by same Fragment class - literally it should be plain ListView with almost same data from database, it will differ by one field only (full list, "visited" items and "not visited").
So here's my parent PlanFragment, which is placed on of tabs of main Activity. It has TabHost and populates 3 Tabs using PlanListFragment:
public class PlanFragment extends Fragment implements OnTabChangeListener {
protected static final String TAG = "PlanFragment";
public static final String TAB_FULL = "full";
public static final String TAB_VISITED = "visited";
public static final String TAB_NOT_VISITED = "not_visited";
private View mRoot;
private TabHost mTabHost;
private int mCurrentTab;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
mRoot = inflater.inflate(R.layout.fragment_plan, container, false);
mTabHost = (TabHost) mRoot.findViewById(android.R.id.tabhost);
setupTabs();
return mRoot;
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
setRetainInstance(true);
mTabHost.setOnTabChangedListener(this);
mTabHost.setCurrentTab(mCurrentTab);
updateTab(TAB_FULL, R.id.tab_plan_full);
}
private void setupTabs() {
mTabHost.setup();
mTabHost.addTab(newTab(TAB_FULL, R.string.label_tab_plan_full,
R.id.tab_plan_full));
mTabHost.addTab(newTab(TAB_VISITED,
R.string.label_tab_plan_visited, R.id.tab_plan_visited));
mTabHost.addTab(newTab(TAB_NOT_VISITED,
R.string.label_tab_plan_unvisited, R.id.tab_plan_not_visited));
}
private TabSpec newTab(String tag, int labelId, int tabContentId) {
TabSpec tabSpec = mTabHost.newTabSpec(tag);
tabSpec.setIndicator(getActivity().getString(labelId));
tabSpec.setContent(tabContentId);
return tabSpec;
}
#Override
public void onTabChanged(String tabId) {
if(TAB_FULL.equals(tabId)) {
updateTab(tabId, R.id.tab_plan_full);
mCurrentTab = 0;
return;
}
if(TAB_VISITED.equals(tabId)) {
updateTab(tabId, R.id.tab_plan_visited);
mCurrentTab = 1;
return;
}
if(TAB_NOT_VISITED.equals(tabId)) {
updateTab(tabId, R.id.tab_plan_not_visited);
mCurrentTab = 2;
return;
}
}
private void updateTab(String tabId, int placeholder) {
FragmentManager fm = getFragmentManager();
if (fm.findFragmentByTag(tabId) == null) {
PlanListFragment plan = new PlanListFragment();
Bundle params = new Bundle();
params.putString(PlanListFragment.TAG, tabId);
plan.setArguments(params);
fm.beginTransaction()
.replace(placeholder, plan, tabId)
.commit();
}
}
}
Here's layout with TabHost:
<?xml version="1.0" encoding="utf-8"?>
<TabHost xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#android:id/tabhost"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
android:padding="5dp" >
<FrameLayout
android:id="#android:id/tabcontent"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:padding="5dp" >
<FrameLayout
android:id="#+id/tab_plan_full"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<include layout="#layout/plan_list" />
</FrameLayout>
<FrameLayout
android:id="#+id/tab_plan_visited"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<include layout="#layout/plan_list" />
</FrameLayout>
<FrameLayout
android:id="#+id/tab_plan_not_visited"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<include layout="#layout/plan_list" />
</FrameLayout>
</FrameLayout>
<TabWidget
android:id="#android:id/tabs"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="-4dp"
android:layout_weight="0" />
</LinearLayout>
</TabHost>
plan_list.xml included on each tab:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/LinearLayout1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Large Text"
android:textAppearance="?android:attr/textAppearanceLarge" />
<ListView
android:id="#+id/listView1"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</ListView>
</LinearLayout>
And finally PlanListFragment in which I plan to setup CursorAdapter for database based on parameter passed from parent Fragment. How do I access ListView here?
public class PlanListFragment extends ListFragment {
protected static final String TAG = "PlanListFragment";
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
Bundle params = getArguments();
Log.d(TAG, params.getString(TAG));
return null;
}
}

Now during my further investigations I found following scheme to work. Key parameter moved to "tag" attribute of call in layout. If there are any drawbacks please advice.
PlanFragment.java
public class PlanFragment extends Fragment implements OnTabChangeListener {
protected static final String TAG = "PlanFragment";
public static final String TAB_FULL = "full";
public static final String TAB_VISITED = "visited";
public static final String TAB_NOT_VISITED = "not_visited";
private View mRoot;
private TabHost mTabHost;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
mRoot = inflater.inflate(R.layout.fragment_plan, container, false);
mTabHost = (TabHost) mRoot.findViewById(android.R.id.tabhost);
setupTabs();
return mRoot;
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
setRetainInstance(true);
mTabHost.setOnTabChangedListener(this);
mTabHost.setCurrentTab(0);
}
private void setupTabs() {
mTabHost.setup();
mTabHost.addTab(newTab(TAB_FULL, R.string.label_tab_plan_full,
R.id.tab_plan_full));
mTabHost.addTab(newTab(TAB_VISITED,
R.string.label_tab_plan_visited, R.id.tab_plan_visited));
mTabHost.addTab(newTab(TAB_NOT_VISITED,
R.string.label_tab_plan_unvisited, R.id.tab_plan_not_visited));
}
private TabSpec newTab(String tag, int labelId, int tabContentId) {
TabSpec tabSpec = mTabHost.newTabSpec(tag);
tabSpec.setIndicator(getActivity().getString(labelId));
tabSpec.setContent(tabContentId);
return tabSpec;
}
#Override
public void onTabChanged(String tabId) {
}
}
fragment_plan.xml
<?xml version="1.0" encoding="utf-8"?>
<TabHost xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#android:id/tabhost"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
android:padding="5dp" >
<FrameLayout
android:id="#android:id/tabcontent"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:padding="5dp" >
<fragment
android:id="#+id/tab_plan_full"
android:tag="plan_full"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
class="com.example.collector.PlanListFragment" />
<fragment
android:id="#+id/tab_plan_visited"
android:tag="plan_visited"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
class="com.example.collector.PlanListFragment" />
<fragment
android:id="#+id/tab_plan_not_visited"
android:tag="plan_not_visited"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
class="com.example.collector.PlanListFragment" />
</FrameLayout>
<TabWidget
android:id="#android:id/tabs"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="-4dp"
android:layout_weight="0" />
</LinearLayout>
</TabHost>
plan_list.xml
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/FrameLayout1"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Large Text"
android:textAppearance="?android:attr/textAppearanceLarge" />
<ListView
android:id="#android:id/list"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</ListView>
</FrameLayout>
PlanListFragment.java
public class PlanListFragment extends ListFragment {
protected static final String TAG = "PlanListFragment";
public PlanListFragment() {}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.plan_list, container, false);
Log.d(TAG,getTag());
return view;
}
}

In child fragment try to access the parent fragment like this:
ParentFragment frag = ((ParentFragment)this.getParentFragment());
frag.sendbutton.setVisibility(View.Visible).invalidate();
Here "sendbutton" is the Button in parent fragment. You should use invalidate() in child fragment to refresh the view if required.

Change a fragment

I have a few fragment which need to show after check RadioButton. How to realize add/replace fragment if I didn't know which fragment was previosly? And How to do default show fragment?

If I understood you correctly,
MainActivity:
public class MainActivity extends FragmentActivity {
FragmentTransaction ft;
Fragment1 frg1;
Fragment2 frg2;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
frg1 = new Fragment1();
frg2 = new Fragment2();
RadioButton btn1 = (RadioButton) findViewById(R.id.radio1);
btn1.setChecked(true);
getSupportFragmentManager().beginTransaction().add(R.id.frame, frg1).commit();
// set listener
((RadioGroup) findViewById(R.id.radio_group)).setOnCheckedChangeListener(new OnCheckedChangeListener() {
#Override
public void onCheckedChanged(RadioGroup group, int checkedId) {
ft = getSupportFragmentManager().beginTransaction();
switch (checkedId) {
case R.id.radio1:
ft.replace(R.id.frame, frg1);
break;
case R.id.radio2:
ft.replace(R.id.frame, frg2);
break;
}
ft.commit();
}
});
}
}
Fragment1:
public class Fragment1 extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
container.removeAllViews();
return inflater.inflate(R.layout.fragment1, null);
}
}
Fragment2:
public class Fragment2 extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
container.removeAllViews();
return inflater.inflate(R.layout.fragment2, null);
}
}
activity_main:
<RadioGroup
android:id="#+id/radio_group"
android:layout_width="wrap_content"
android:layout_height="wrap_content" >
<RadioButton
android:id="#+id/radio1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="fragment1" />
<RadioButton
android:id="#+id/radio2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="fragment2" />
</RadioGroup>
<FrameLayout
android:id="#+id/frame"
android:layout_width="match_parent"
android:layout_height="match_parent" >
</FrameLayout>
fragment1.xml:
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="Fragment1" >
</TextView>
fragment2.xml:
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="Fragment2" >
</TextView>

my fragment is still in the UI

this is my first fragment which open a fragment through xml layout
public class ListFrag extends SherlockFragment implements OnItemClickListener
{
Context c;
List<ReferalRow> referal_RowItems;
DoctorDaoImpl doctorDao;
DoctorServiceImpl service;
DoctorValidator doctorValidator;
View layoutView;
ListView doctoListView;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
layoutView = inflater.inflate(R.layout.activity_refer_mangmnt, null);
return layoutView;
}
and this is my activity_refer_mangmnt.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal"
android:padding="5dp" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:layout_weight="2"
android:padding="2dp">
<ListView
android:id="#+id/listView_refer_list"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:dividerHeight="1dp"
android:divider="#android:color/black"
android:choiceMode="singleChoice"
android:listSelector="#drawable/list_selector" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1"
android:background="#drawable/rightpanel_back">
<fragment
android:id="#+id/detail_fragment"
android:tag="detailfrag"
android:layout_width="match_parent"
android:layout_height="match_parent"
class="com.example.app1.DetailsFrag" />
</LinearLayout>
`</LinearLayout>
and this is my DetailFrag class
public class DetailsFrag extends SherlockFragment
{
ExpandableListView detailList;
TextView tvMessage;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
contentView = inflater.inflate(R.layout.activity_refer_view, null);
detailList = (ExpandableListView) contentView.findViewById(R.id.ep_detail_view);
tvMessage = (TextView)contentView.findViewById(R.id.tv_textView);
return contentView;
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onActivityCreated(savedInstanceState);
if(id==0)
{
detailList.setVisibility(View.GONE);
tvMessage.setText("Click on the item on the left panel to view the details");
}
else
{
detailList.setVisibility(View.VISIBLE);
tvMessage.setVisibility(View.GONE);
}
and this is my onItem click listener in LIstFrag
FragmentTransaction ft = getFragmentManager().beginTransaction();
Fragment lastFrag = getFragmentManager().findFragmentByTag("detailfrag");
if(lastFrag!=null)
ft.remove(lastFrag);
Fragment fragment = Fragment.instantiate(c, DoctorDetailsFrag.class.getName(),arguments);
ft.replace(R.id.detail_fragment, fragment);
ft.commit();
i need when first time i want to display a message in the right panel after click on the item in the list i want to disappear that message. but here the message is not remove from the fragment. its displayed in the backgrnd of new fragment. y it is?

Try:
ft.addToBackStack(null)
after you call: ft.remove(lastFrag);
Perhaps this link can help you to understand this transaction:
http://developer.android.com/guide/components/fragments.html#Transactions
Another way is to to reuse your lastFrag when it's not null. Then you need a method in your DetailFrag that is called from your clickListener.

Fragment overlaying an Activity layout

I'm having problems working with fragments. The problem is: I have a layout in my activity with a ListView. When i select an item in this ListView, instantiates a fragment replacing the activity layout. My result is both fragment and activity contents are showing on screen, overlaying each other. What can I fix that (the fragment just replacing the activity content)? Here is the codes:
activityLayout.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/activity"
android:orientation="vertical">
<FrameLayout android:id="#+id/fragment_to_replace"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="visible"
android:orientation="vertical"
android:layout_gravity="center" >
<TextView android:id="#+id/textView"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:visibility="visible"
android:text="#string/textView_select_table"
android:textSize="30dp"/>
<ListView android:layout_marginTop="20dp"
android:layout_width="fill_parent"
android:layout_height="200dp"
android:id="#+id/listView"
android:visibility="visible"
android:paddingTop="40dp" />
</FrameLayout>
</LinearLayout>
Activity.java
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity);
View view = findViewById(R.id.activity);
//Getting the ListView
ListView listView = (ListView) view.findViewById(R.id.listView);
listView.setTextFilterEnabled(true);
//Setting the adapter
listView.setAdapter(new Adapter(this));
listView.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
//Creates a fragment
addFragment();
}
});
}
public void addFragment(){
MyFragment newFragment;
FragmentTransaction newFragmentTransaction = getSupportFragmentManager().beginTransaction();
newFragment = (MyFragment) getSupportFragmentManager()
.findFragmentById(R.id.fragment);
if (newFragment == null){
newFragment = new MyFragment(this, getSupportFragmentManager());
newFragmentTransaction.replace(R.id.fragment_to_replace,
new SelectDrinkFragment(this, getSupportFragmentManager()));
newFragmentTransaction.addToBackStack(null);
newFragmentTransaction.commit();
}
}
fragmentLayout.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/fragment"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:visibility="visible"
android:text="#string/textView_two"
android:textSize="20dp"/>
<LinearLayout android:layout_marginTop="10dp"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:visibility="visible"
android:text="#string/textView" />
<TextView android:id="#+id/textView_two"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:visibility="visible"/>
</LinearLayout>
<TextView
android:id="#+id/textView_three"
android:layout_marginTop="10dp"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:visibility="visible"
android:text="#string/textView_three"/>
<ListView
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:id="#+id/listView_two"
android:visibility="visible"
android:paddingTop="40dp" />
</LinearLayout>
Fragment.java
public View onCreateView(final LayoutInflater inflater, final ViewGroup container, Bundle saveInstanceState){
View view = inflater.inflate(R.layout.fragment, container, false);
final ListView listView = (ListView) view.findViewById(R.id.listView_two);
CharSequence [] list = getResources().getStringArray(R.array.array);
listView.setAdapter(new ListAdapter(getContext(), list));
return view;
}
ListAdapter.java
public class ListAdapter extends BaseAdapter{
private Context context;
private CharSequence[] drinkArraySize;
public ListAdapter(Context context, CharSequence[] array){
super();
this.context = context;
this.array= array;
}
#Override
public int getCount() {
return array.length;
}
#Override
public Object getItem(int position) {
return null;
}
#Override
public long getItemId(int position) {
return 0;
}
public Context getContext(){
return context;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
LinearLayout linearLayout = new LinearLayout(getContext());
RadioButton radioButton = new RadioButton(getContext());
radioButton.setText(array[position]);
linearLayout.addView(radioButton);
return linearLayout;
}
}

FragmentTransaction.replace() looks like it only replaces another fragment (and not just any View), so I'm pretty sure this is expected behavior (or at least, I know I've had this happen to me before). I suppose you have a few options:
I don't see in your code anything that would make the fragment's background opaque. You could try that first and see if it helps. If it does, that might be the simplest.
You could just set the other items' visibilities to View.GONE at the same time you perform your transaction, but that has some issues as far as backstack goes.
You could replace the ListView and TextView with a ListFragment instead. This is probably the "best" way to do it, but also is probably the most work.