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fragment doesn't show in framelayout in linearlayout

I use fragments to display multiple views in one activity. I have 2 framelayouts in one linearlayout. The onCreate and onCreateView of the fragment gets called but the view of the fragment is not displayed. Is what i'm trying to do not possible? Or is there a way to fix issue?
Layout of the activity:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:orientation="vertical"
tools:context=".view.activity.StandardFlowActivity">
<FrameLayout
android:id="#+id/standardFlowDownloadContainer"
android:layout_width="match_parent"
android:layout_height="match_parent">
</FrameLayout>
<FrameLayout
android:id="#+id/standardFlowBaseContainer"
android:layout_width="match_parent"
android:layout_height="match_parent">
</FrameLayout>
</LinearLayout>
Layout of the fragment
<FrameLayout 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"
tools:context="com.example.sennevervaecke.crossexperience.view.fragment.WedstrijdFragment">
<ListView
android:id="#+id/wedstrijdListView"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</FrameLayout>
Fragment Class
public class WedstrijdFragment extends Fragment implements AdapterView.OnItemClickListener{
private ArrayList<Wedstrijd> wedstrijden;
private WedstrijdFragmentCom communication;
public WedstrijdFragment() {
// Required empty public constructor
}
#Override
public void onCreate(Bundle savedInstanceState) {
Log.e("wedstrijdFragment", "onCreate is called");
super.onCreate(savedInstanceState);
wedstrijden = LocalDB.getWedstrijden();
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
Log.e("wedstrijdFragment", "onCreateView is called");
View view = inflater.inflate(R.layout.fragment_wedstrijd, container, false);
ListView listView = view.findViewById(R.id.wedstrijdListView);
WedstrijdAdapter adapter = new WedstrijdAdapter(getContext(), wedstrijden);
listView.setAdapter(adapter);
listView.setOnItemClickListener(this);
return view;
}
#Override
public void onAttach(Activity activity) {
super.onAttach(activity);
try {
communication = (WedstrijdFragmentCom) activity;
} catch (ClassCastException e){
e.printStackTrace();
}
}
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
communication.onWedstrijdItemClick(wedstrijden.get(i));
}
}
Code in the onCreate of the activity to add the fragment:
wedstrijdFragment = new WedstrijdFragment();
getSupportFragmentManager().beginTransaction().add(R.id.standardFlowBaseContainer, wedstrijdFragment, "wedstrijd").commit();
Thanks in advance!

Your first layout standardFlowDownloadContainer width and height is match_parent , so the standardFlowBaseContainer FrameLayout is out of the screen. you can change your standardFlowDownloadContainer's height to 20dp and run your project , you will see your Fragment content.

How to combine a layout and a view?

I am making an 2D Android game with Android Studio and I have a activity_customer.xml file and I have a MyView a
but when I use like this, MyView a isn't seen on the screen but activity_customer.xml is seen on the screen :
Customer.java:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
MyView a = new MyView(this);
setContentView(a);
setContentView(R.layout.activity_customer);
}
But if I use like this,MyView a is seen on the screen but activity_customer.xml isn't seen on the screen :
Customer.java:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
MyView a = new MyView(this);
setContentView(R.layout.activity_customer);
setContentView(a);
}
So I want to seen both MyView a and activity_customer.xml ,How can I combine them in a one screen?
This is my activity_customer.xml :
<?xml version="1.0" encoding="utf-8"?>
<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"
tools:context="com.example.asdf.catchtheball.main">
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:text="Button" />
</RelativeLayout>

if you created your own view class you can add it to your activity view with something like this:
RelativeLayout mainLayout = (RelativeLayout)findViewById(R.id.relativeLayout); //Your main element at activity's xml file
mainLayout.addView(yourView); // replace your 'a' object with 'yourView'

Android spinner remove dropdown vertical extra space / padding

I am new to android app developing as i was creating spinner i noticed a extra space / padding vertically to drop down list of the spinner at the start and end of the drop down.
MainActivity.java:
public class MainActivity extends AppCompatActivity
{
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Spinner sr = (Spinner) findViewById(R.id.spinner);
String[] days = getResources().getStringArray(R.array.days);
ArrayAdapter<String> ar = new ArrayAdapter<>(this, R.layout.single_row, days);
sr.setAdapter(ar);
}
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#666666"
tools:context="com.xxxxx.defaultspinner.MainActivity">
<Spinner
android:id="#+id/spinner"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_marginTop="20dp"
android:spinnerMode="dialog"
android:background="#898989">
</Spinner>
</RelativeLayout>
single_row.xml
<TextView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/app_name"
android:textColor="#FFFFFF"
android:textSize="26sp"
android:background="#214161">
</TextView>
I set background of all the views to different color so that i can identify the source of the extra space / padding. But the the extra space / padding has white background which none of the view has.
Note this is not because of the spinnerMode="dialog" option. this behavior is also happens when spinnerMode="dropdown". How can i remove this space ? or i am doing something wrong ?

You just need to override the getDropDownView method in the adapter.
#Override
public View getDropDownView(int position, View convertView, ViewGroup parent) {
parent.setPadding(0, 0, 0, 0);
return convertView;
}

try adding this to your TextView
android:includeFontPadding="false"
it will remove the TextView extra top and bottom padding

How to change ImageView source from different XML?

I want to change images in my popupwindow. I am trying to change ImageView image source which is in test.xml while my contentView is activity_main. When I try to just call imageView.setImageResource(android.R.drawable.ic_menu_help); it gives me nullpointerexception I realized i have to use inflate method, but when I use it it doesn't do what I want.I know there is a lot of questions regarding this, but none of them really helped me.
This is activity_main.xml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/relative"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.android.popupwindow.MainActivity">
<Button
android:text="Test"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/button"
android:layout_centerVertical="true"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
</RelativeLayout>
test.xml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#android:color/holo_blue_dark"
android:id="#+id/test1"
>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/linear1">
<ImageView
android:layout_width="75dp"
android:layout_height="75dp"
android:src="#android:drawable/btn_star_big_on"
android:id="#+id/imageView1"
android:layout_weight="1"
/>
</LinearLayout>
</RelativeLayout>
my main.java:
public class MainActivity extends AppCompatActivity {
private PopupWindow popupWindow;
private RelativeLayout relativeLayout;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button test = (Button) findViewById(R.id.button);
relativeLayout = (RelativeLayout) findViewById(R.id.relative);
final View view1 = getLayoutInflater().inflate(R.layout.test, null);
ImageView imageView = (ImageView) view1.findViewById(R.id.imageView1);
imageView.setImageResource(android.R.drawable.ic_menu_help); //Image source is not changed in my popupWindow,
// but it is changed when I call relativeLayout.addView(view1);
test.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
//relativeLayout.addView(view1); // <-- this does the trick, but its not what i want
View container = getLayoutInflater().inflate(R.layout.test, null);
popupWindow = new PopupWindow(container, android.app.ActionBar.LayoutParams.MATCH_PARENT, android.app.ActionBar.LayoutParams.WRAP_CONTENT, true);
popupWindow.showAtLocation(relativeLayout, Gravity.BOTTOM, 0, 0);
container.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View view, MotionEvent motionEvent) {
popupWindow.dismiss();
return true;
}
});
}
});
}
}

You're inflating two separate views. Obviously what you do in one will have no impact on the other. You should set the popup view to your originally inflated view:
popupWindow = new PopupWindow(view1,
RelativeLayout.LayoutParams.MATCH_PARENT,
RelativeLayout.LayoutParams.WRAP_CONTENT,
true);

viewPager not displaying fragment

for this project, I have tabs that have to display something under them and i'm using view pager but for some reason, the fragment layout isn't showing up on screen. I get a blank screen but there is no error or anything. I have been googling and searching for hours now and even started a new project just to make sure it was not a build error but still no luck in finding a solution to my problem.
I have done examples like this many times and used the exact same steps but for some reason, it just isn't working this time. Any help would be greatly appreciated
Here is my mainActivity class
public class MainActivity extends ActionBarActivity {
Toolbar toolbar;
ViewPager myViewPager;
SlidingTabLayout mySlidingTabs;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
myViewPager = (ViewPager) findViewById(R.id.viewPager);
myViewPager.setAdapter(new MyPagerAdapter(getSupportFragmentManager(), this));
mySlidingTabs = (SlidingTabLayout) findViewById(R.id.sliding_tabs);
mySlidingTabs.setViewPager(myViewPager);
}
}
Here is my custom adapter class
public class MyPagerAdapter extends FragmentPagerAdapter {
private Context context;
private String[] tabNames = {"Beverages", "Deli & Bakery", "Fresh Produce", "Health & Beauty", "Meat & Seafood", "Natural Foods", "Pet Care"};
public MyPagerAdapter(FragmentManager fm, Context context) {
super(fm);
this.context = context;
}
#Override
public Fragment getItem(int position) {
if (position == 0) {
return new Beverages();
}
else if (position == 1) {
return new DeliBakery();
}
return null;
}
#Override
public int getCount() {
return 2;
}
#Override
public CharSequence getPageTitle(int position) {
return tabNames[position];
}
}
Here is my main activty.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<include
android:id="#+id/toolbar"
layout="#layout/toolbar_layout"
android:layout_height="wrap_content"
android:layout_width="match_parent" />
<!-- The Sliding tab -->
<bello.myapplication.SlidingTabLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/sliding_tabs"/>
<!-- The pager that allows us to swipe between fragments -->
<android.support.v4.view.ViewPager
android:id="#+id/viewPager"
android:layout_width="match_parent"
android:layout_height="0px"
android:layout_weight="1"
android:background="#android:color/white" />
</LinearLayout>
and here is one of my tab's xml file
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
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="Tab fragment 1"
android:textSize="50dp"
android:padding="5dp" />
</RelativeLayout>
Here is one of my fragment classes
public class Beverages extends Fragment {
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.beverages_tab, container, false);
return view;
}
}

When something strange like this happens, try to use Log.i("title", "message") to track if every class/methods are being called.
In your case, it seens that your viewpager isn't in the screen.
If I understood your code, your <include> tag is including the second xml code you posted right?
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
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="Tab fragment 1"
android:textSize="50dp"
android:padding="5dp" />
</RelativeLayout>
It looks like your layout_height="match_parent" is filling all the space on your screen, giving no space to your ViewPager being inflated by the system, try to change it to layout_height="wrap_content and you should be done.
If not, try to change the background of your ViewPager to check if it is on the screen and is not being hided by something else.

Figured out the problem. The viewpager background color and the background color of the tabs where the same so it made it look like there was a black activity. So for anyone else out there with the same problem, try changing either the text color of your tabs.xml or change the background of your viewpager