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Scrolling Both horizontally and vertically . how can i show my java code in a code view and scroll my code both horizontally and vertically?

I want to show my java code in a fragment with a code view now my problem is that my code perform only for scrolling down but i want to scroll may code horizontally and vertically at the same time so now what can i do?
i already tried by nesting horizontalscrollview and scrollview but it dose not working and my app gone crush.
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="saiful" />
<thereisnospon.codeview.CodeView
android:id="#+id/codeViewId"
android:layout_width="match_parent"
android:layout_height="match_parent">
</thereisnospon.codeview.CodeView>
</LinearLayout>
</ScrollView>
and my java file is
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_java, container, false);
codeView = view.findViewById(R.id.codeViewId);
codeView.setTheme(CodeViewTheme.ANDROIDSTUDIO).fillColor();
codeView.showCode(Content.java);
return view;
}

Do not mess with Horizontal and vertical scrollviews. Here is good library for that. Give it a try.
"A bidirectional panning container for Android with native scrolling for APIs 7 and up."

How to add a title to a fragment in Android

In AndroidStudio, I selected "New->Fragment->Fragment (List)" to create a list of items. It works fine and displays all the items; however, I would like to have a title at the top.
If I add another TextView to the "fragment_item_list.xml" file, then the title appears in all the items in the list. From other questions I figured that if I create another LinearLayout xml layout file (something like "list_header.xml") and put a TextView in it, I can use a layout inflater to inflate this layout in the fragment activity, e.g. in onCreateView,
View header = inflater.inflate(R.layout.list_header,container,false);
but then I don't know what to do with header to make it display somewhere in the fragment. I can add it to the original activity by calling container.addView(header); but how can I add it to the fragment?
I don't want to change the ActionBar title, firstly just for aesthetics, and secondly because the fragment covers it up. Ideally there would be a header like in an alert dialog.

Let me try to understand you. You want to add a title to your fragment list (like an header), not in the ActionBar. Right?
Looking the fragment_item_list.xml we have this: (I follow your steps: "New->Fragment->Fragment (List)")
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.RecyclerView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginLeft="16dp"
android:layout_marginRight="16dp"
app:layoutManager="LinearLayoutManager"
tools:listitem="#layout/fragment_item" />
The RecyclerView is a container used for populate a list, in other words, the RecyclerView (or ListView) contain all the list only. So, you have to add another container (like LinearLayout, RelativeLayout, etc.) as root of the layout to add more views to the layout. Example using the LinearLayout:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="#+id/text_header"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Hello World! I'm a header!"/>
<android.support.v7.widget.RecyclerView
android:id="#+id/list"
android:name="com.veroapps.myapplication.ItemFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginLeft="16dp"
android:layout_marginRight="16dp"
app:layoutManager="LinearLayoutManager"
tools:listitem="#layout/fragment_item" />
</LinearLayout>
With this you will have a list with a title at the top. Now, you can manage the title TextView in the ItemFragment(name of the fragment generated by Android Studio). And of course there are more ways to do that, but this is an easy one.
Hope this help you.

In your Fragment java class, there should be a method called onCreateView this is where you set the layout for your Fragment (and where the list is added). It will look something like this:
public static class ExampleFragment extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.example_fragment, container, false);
}
}
In this Fragment the layout is inflated by this code inflater.inflate(R.layout.example_fragment, container, false); and this means there's is an xml file defining the layout called example_fragment.xml.
Your code will be the same, when you find this XML file. You can add other views inside it.
You will want to add another TextView above the RecyclerView or ListView already in that file.
Something like this:
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
>
<TextView
...
android:text="YOUR TITLE" />
<RecyclerView
... />
</LinearLayout>

Cardview shadow redraws itself after rotation or rotten cardview

I discovered very strange behavior of CardView's shadow.
I just start to develop an app, and there is absolutely no any business-logic or something like that. But anyway...
I just add few views to my fragments layout, and discover, that after every screen rotation cardview's shadow getting darker. After 5-6 rotations it already looks like completely black. I guess, the problem can be somewhere in canvas, but no idea where and why - i even didn't start customize anything.
I hope somebody already solve similar problem with cardview, and now can share that experience.
Thank you!
Here is screenshots, code, dependencies and xml:
XML
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:iot="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center_horizontal"
android:orientation="vertical">
<android.support.v7.widget.CardView
android:id="#+id/content_container"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margin="#dimen/common_gap"
iot:cardElevation="10dp"
iot:cardUseCompatPadding="true">
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center_horizontal"
android:orientation="vertical">
<DatePicker
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:layout_marginTop="#dimen/common_gap"
android:calendarViewShown="true"
android:spinnersShown="false" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="?attr/selectableItemBackground"
android:paddingLeft="#dimen/common_gap"
android:paddingRight="#dimen/common_gap"
android:text="#string/choose_date_confirm_button"
android:textColor="#color/colorPrimary" />
</LinearLayout>
</ScrollView>
</android.support.v7.widget.CardView>
</LinearLayout>
Java (Nothing else in fragment class)
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.date_choose_fragment, container, false);
return rootView;
}
dependencies
compile 'com.android.support:appcompat-v7:25.0.1'
compile 'com.android.support:cardview-v7:25.0.1'
Screenshots

This is most likely not due to any bug with CardView or its shadow draw. Rather, this is likely the result of multiple Fragments with transparent backgrounds, stacked one atop another, and the darkening shadow is the additive effect of the shadows' translucency.
Active Fragment instances are automatically recreated when the Activity is, which happens by default upon an orientation change. If you're unconditionally adding a dynamic Fragment instance, for example, in the Activity's onCreate() method, that one will be added along with any instances recreated from the Activity's prior state. Effectively, each time you rotate your device, you're adding one more Fragment to the stack, and the shadow gets a little bit darker.
This can be demonstrated with just a simple TextView, to show that it's not an issue specific to CardView.
fragment.xml
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center"
android:text="Hello world!"
android:textSize="60sp"
android:textStyle="bold"
android:textColor="#fffbc02d"
android:shadowColor="#70707070"
android:shadowDx="10"
android:shadowDy="10"
android:shadowRadius="10" />
In the example Activity's onCreate() method, we add a dynamically created Fragment with the given layout, as described above.
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getFragmentManager().beginTransaction()
.add(android.R.id.content, new MainFragment()).commit();
}
public static class MainFragment extends Fragment {
public MainFragment() {}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment, container, false);
}
}
}
This image shows successive captures after having rotated the device, twice for each step.
If you were to put a log print in the Fragment's onCreateView() method, you would see that an additional instance is created upon each rotation. At the end of that sequence, we have eleven Fragments in play.
One way to prevent this is to check if the Fragment is already attached to the FragmentManager before creating and adding a new one, which we can do by adding a tag in the FragmentTransaction. For example:
if (getFragmentManager().findFragmentByTag("main") == null) {
getFragmentManager().beginTransaction()
.add(android.R.id.content, new MainFragment(), "main").commit();
}
Alternatively, if you don't need to dynamically transact the Fragment after startup, you could instead statically define it in the layout, and the FragmentManager will handle the check and transaction itself.
<fragment
android:id="#+id/main_fragment"
android:name="com.mycompany.myapp.MainFragment"
android:layout_width="match_parent"
android:layout_height="match_parent" />

getActivity().findViewById(int id) returns null even after fragment has completed building

I'm following the android training in android's website. I am stuck at some point in fragments. The problem is that I can't get the reference to my textview in a fragment.
TextView view = (TextView) getActivity().findViewById(R.id.article_s);
I have two fragments in one activity. One is a plain simple ListFragment and the other is a plain simple TextView. Here is fragments and activity layout xml files.
ArticleFragment:
<!-- This is fragment_article.xml -->
<?xml version="1.0" encoding="utf-8"?>
<TextView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Some Text"
android:textSize="18sp"
android:id="#+id/article_s"/>
MainActivity (My container to all fragments)
<!-- This is activity_main.xml -->
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent">
<fragment
android:layout_height="match_parent"
android:name="com.example.bora.fragmentsmyway.HeadlinesFragment"
android:id="#+id/headlines_fragment"
android:layout_weight="1"
android:layout_width="0dp" />
<fragment
android:layout_height="match_parent"
android:name="com.example.bora.fragmentsmyway.ArticleFragment"
android:layout_weight="2"
android:id="#+id/article_fragment"
android:layout_width="0dp" />
</LinearLayout>
There is a public method in my ArticleFragment which takes a string to update the content of the textview of itself:
public void updateView(String article) {
TextView view = (TextView) getActivity().findViewById(R.id.article_s);
try{
view.setText(article);
} catch (NullPointerException e) {
e.printStackTrace();
}
}
After all the views are created, I call the updateView method from my MainActivity. But I get a NullPointerException when I try to find the article TextView. I have tried cleaning, changing the TextView's resource id.
However I have found a solution for this problem. I don't know why but it seems to work when I wrap TextView with a LinearLayout in the fragment_article.xml:
<LinearLayout
xmlns:android="..."
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Some Text"
android:textSize="18sp"
android:id="#+id/article_s" />
</LinearLayout>
But I am wondering this: How can, in the tutorial samples, above code work and can't work when I wrote? I checked every code letter by letter but there is no difference between mine ant theirs. Is it because of the versions?
I'm working with the API 23 which is marshmallow.

Make sure you fragment is attached to the activity before calling updateView
this
TextView view = (TextView) getActivity().findViewById(R.id.article_s);
will give you NPE cause it does not belong to the activity
The views belong to the Fragments in which case you do
View view = inflater.inflate(R.layout.fragment_layout, container, false);
TextView textView = (TextView) view.findViewById(R.id.article_s);
Specifically, the fragment can access the Activity instance with getActivity() and easily perform tasks such as find a view in the activity layout:
Read Communicating with activity # https://developer.android.com/guide/components/fragments.html
So you use getActivity to find views that belong to activity which is not the case in your code.
Edit -
Wrapping it with a LinearLayout should not make any difference as it is just a viewgroup. If you just need a single textview no need for LinearLayout.
Read the accepted answer at : Difference between getActivity() and view in Fragment

use this code : you given wrong id to on TextView
TextView view = (TextView) getActivity().findViewById(R.id.article_s);

This is return NPE because your try to find the wrong id.
There are two different way you can resolve issue.
1) First one
<TextView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Some Text"
android:textSize="18sp"
android:id="#+id/article"/>
TextView view = (TextView) getActivity().findViewById(R.id.article);
Another way keep your XML as it is & try to do below change in java code.
2) Second One
<TextView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Some Text"
android:textSize="18sp"
android:id="#+id/article_s"/>
TextView view = (TextView) getActivity().findViewById(R.id.article_s);

It doesn't work like this inside a fragment class by the way you should upload your main activity codes or your fragment class if you are using it inside the main activity, you don't need to use getActivity()
if it is inside a fragment class you need to apply it like this:
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.your_fragment_layout_xml, container, false);
TextView AboutUs = (TextView) rootView.findViewById(R.id.id_of_textview);

How to place ListView inside of a Page?

I currently have some swipe pages and in all of them I want to have list with different data.
I am still pretty new to android so I tried all possible options I could come up with:
First I tried adding some xml layouts to the insides of the page.
Second I tried creating and populating lists pragmatically.
None of the above worked out for me.
For starters I want to check if I understand the concept:
Swipe layout contains pages and data could be passed to them by getItem() Fragment type content.
And now how to achieve what I want:
I have to add LinearLayout add a child ListView and finally add a child for that the TextView element to main page template in my layout/main.xml and create a data population method.
Is there something wrong in my reasoning and that is why I can't find answer or I just have not found the right source?
CODE EXAMPLES:
main.xml
<android.support.v4.view.ViewPager xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/pager"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity" >
<!--
This title strip will display the currently visible page title, as well as the page
titles for adjacent pages.
-->
<android.support.v4.view.PagerTitleStrip
android:id="#+id/pager_title_strip"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="top"
android:background="#33b5e5"
android:paddingBottom="4dp"
android:paddingTop="4dp"
android:textColor="#fff" />
</android.support.v4.view.ViewPager>
list_layout.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<ListView
android:id="#+id/listView1"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</ListView>
</LinearLayout>
MainActivity.java
...
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// Create the adapter that will return a fragment for each of the three primary sections
// of the app.
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
// Set up the ViewPager with the sections adapter.
mViewPager = (ViewPager) findViewById(R.id.pager);
mViewPager.setAdapter(mSectionsPagerAdapter);
}
...

You can do this by declaring an xml say listview.xml in which define your ListView.
You can either create a new TextView pro grammatically or create the new layout say titleview.xml in which write your title view using TextView.
Pro grammatically you can inflate both the views and pass your main layout parent view as parent to these child views.
LayoutInflater inflater = getLayoutInflater();
ListView listview = inflater.inflate(R.layout.list_view, parent);
TextView textview = inflater.inflate(R.layout.textview, parent);
layout.addView(textview);
layout.addView(listview);