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How to change multiple fragments by clicking on a single button in android?

Greeting!
I’m practicing on fragments topic. My main issue is how to change multiple fragments by clicking a single button “NEXT” or “PREVIOUS” as you may know some apps or books change pages by clicking on the next or previous buttons. If there are only two are four fragments then no issue to add buttons but what if there are multiple fragments like 50 or 100? First I try to find solutions from Google and YouTube but I find that we can change pictures through this method. Is it possible that we can change fragments through this method or not if possible so please some articles with the same solutions to share your experience? Or I should need to use images to do this. My main activity java code and XML code are below and the first fragment and code other three fragments are also the same.
// Main_Activity.java
package com.test.fragment_practice;
import androidx.appcompat.app.ActionBar;
import androidx.appcompat.app.AppCompatActivity;
import androidx.fragment.app.Fragment;
import androidx.fragment.app.FragmentManager;
import androidx.fragment.app.FragmentTransaction;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.LinearLayout;
import com.test.fragment_practice.Fragments.FirstFragment;
import com.test.fragment_practice.Fragments.ForthFragment;
import com.test.fragment_practice.Fragments.SecondFragment;
import com.test.fragment_practice.Fragments.ThirdFragment;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends AppCompatActivity {
LinearLayout layout;
Button btn1,btn2;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
layout = (LinearLayout) findViewById(R.id.linearLayout2);
btn1 = (Button) findViewById(R.id.btnpre);
btn2 = (Button) findViewById(R.id.btnnxt);
btn1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
FirstFragment fragment = new FirstFragment();
FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
fragmentTransaction.replace(R.id.linearLayout2, fragment);
fragmentTransaction.commit();
}
});
btn2.setOnClickListener((view) ->{
SecondFragment fragment2 = new SecondFragment();
FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
fragmentTransaction.replace(R.id.linearLayout2, fragment2);
fragmentTransaction.commit();
});
}
}
//activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity">
<LinearLayout
android:id="#+id/linearLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#FF3700B3"
android:orientation="horizontal">
<Button
android:id="#+id/btnpre"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_margin="5dp"
android:layout_weight="1"
android:backgroundTint="#FF0000"
android:text="Previous"
android:textColor="#6900FF"
android:textSize="24sp" />
<Button
android:id="#+id/btnnxt"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="5dp"
android:layout_weight="1"
android:backgroundTint="#FFFF00"
android:text="Next"
android:textColor="#6900FF"
android:textSize="24sp" />
</LinearLayout>
<LinearLayout
android:id="#+id/linearLayout2"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"/>
</LinearLayout>
// First_Fragment.java
package com.test.fragment_practice.Fragments;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import androidx.fragment.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import com.test.fragment_practice.R;
import com.test.fragment_practice.SecondActivity;
public class FirstFragment extends Fragment {
public FirstFragment() {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
super.onCreateView(inflater, container, savedInstanceState);
return inflater.inflate(R.layout.fragment_first, container, false);
}
}

How do I change the textview of a Fragment from WITHIN the fragment itself?

I have a MainActivity that creates 3 Fragments. Once I got into the first Fragment, I wish to change the Textview I have in the layout of THIS Fragment, from within this Fragment. I cannot see the 'findViewbyId' method popping up in the IDE when I try to access the TextView this way. Can someone please help me out? Here is the code for the Fragment which I want to carry out the operation in called 'FragmentOne'. The code is for 'FragmentOne.jav'
package com.iotaconcepts.aurum;
import android.app.Activity;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import android.widget.Toast;
import com.iotaconcepts.aurum.R;
import java.io.*;
import java.util.*;
public class OneFrangment extends Fragment
{
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
Fragment fc=getTargetFragment();
TextView tv=(TextView)fc.findViewById(R.id.textview);//NOT WORKING
try
{
BufferedReader br=new BufferedReader(new InputStreamReader(getActivity().getAssets().open("symp.txt")));
String parse1;
while((parse1=br.readLine())!=null)
{
Toast.makeText(getActivity(), parse1, Toast.LENGTH_LONG).show();
tv.setText(parse1 + "\n");
}
}
catch(Exception e)
{
tv.append("wtf\n");
Toast.makeText(getActivity(),"SORRY!", Toast.LENGTH_LONG).show();
}
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_one, container, false);
}
}
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"
tools:context="info.androidhive.materialtabs.fragments.OneFragment">
android:w
<TextView
android:id="#+id/textview"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:text="Hello"
/>

You need to assign the inflater.inflate method to a View before you can find views from it.
View v = inflater.inflate(R.layout.fragment_one, container, false);
TextView tv=(TextView)v.findViewById(R.id.textview);
...
return v;

Unable to replace/navigate fragments

I am trying to navigate from one fragment to another. These two fragments are 100% different, there is no ViewPager or something like that to connect them. Here is the code.
fragment_view1.xml
<?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"
android:orientation="vertical"
android:id="#+id/firstView">
<TextView
android:id="#+id/viewOneText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginLeft="92dp"
android:layout_marginTop="182dp"
android:text="First View"
android:textAppearance="?android:attr/textAppearanceLarge" />
<Button
android:id="#+id/viewOneBtn"
style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignRight="#+id/viewOneText"
android:layout_below="#+id/viewOneText"
android:layout_marginTop="17dp"
android:text="Click Here" />
<include layout = "#layout/drop_down"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginTop="15dp"
android:layout_alignParentBottom="true"/>
<FrameLayout
android:id="#+id/fragment_view"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</RelativeLayout>
custom_view.xml
<?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"
android:orientation="vertical"
android:id="#+id/customFragment" >
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="174dp"
android:text="Custom Fragment"
android:textAppearance="?android:attr/textAppearanceLarge" />
</RelativeLayout>
FirstView.java (uses fragment_view1.xml)
package com.example.fragmenttest;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.TextView;
public class FirstView extends DropDownMenu
{
private TextView firstText;
private Button btn;
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
View view = inflater.inflate(R.layout.fragment_view1,container,false);
firstText = (TextView)view.findViewById(R.id.viewOneText);
btn = (Button)view.findViewById(R.id.viewOneBtn);
btn.setOnClickListener(new ButtonEvent());
return view;
}
private class ButtonEvent implements OnClickListener
{
#Override
public void onClick(View v)
{
// Create new fragment and transaction
Fragment newFragment = new CustomView();
FragmentTransaction transaction = getFragmentManager().beginTransaction();
// Replace whatever is in the fragment_container view with this fragment,
// and add the transaction to the back stack
transaction.replace(R.id.fragment_view, newFragment);
transaction.addToBackStack(null);
// Commit the transaction
transaction.commit();
}
}
}
CustomView.java (uses custom_view.xml)
package com.example.fragmenttest;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.TextView;
public class CustomView extends Fragment
{
private TextView secondText;
private Button secondViewBtn;
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
View view = inflater.inflate(R.layout.custom_view,container,false);
return view;
}
}
In FirstView.java, when I click on the button, I need to move to the Fragment CustomView. But instead moving, it simply replaces everything in CustomView on top of FirstView. Below images will explain it better.
FirstView alone
CustomView alone
When the button is FirstView clicked
Why it is happening like this?

You are trying to replace firstView with the new fragment, but firstView is not a fragment, its' a RelativeLayout.
You cannot replace a fragment defined statically in the layout file. You can only replace fragments that you added dynamically via a FragmentTransaction.
None of your Layout contains fragment in layout.
<fragment
android:id="#+id/fragment1"
android:layout_width="march_parent"
android:layout_height="match_parent"></fragment>
A new Fragment will replace an existing Fragment that was previously added to the container.
Take look on this.

If you need to replace one fragment with another then fallow undermentioned :
TalkDetail fragment = new TalkDetail();
// TalkDetail is name of fragment which you need to put while replacing older one.
Bundle bundle = new Bundle();
bundle.putString("title", m_ArrayList.get(arg2).title);
bundle.putString("largeimg", m_ArrayList.get(arg2).largeimg);
bundle.putString("excert", m_ArrayList.get(arg2).excert);
bundle.putString("description", m_ArrayList.get(arg2).description);
bundle.putString("cat", m_ArrayList.get(arg2).cat);
bundle.putString("header_title", "Talk");
//bundle.putInt("postid", m_ArrayList.get(arg2).postid);
fragment.setArguments(bundle); ((BaseContainerFragment)getParentFragment()).replaceFragment(fragment, true);
Here's your BaseContainerFragment.java class that will manage a lot of stuff for you.
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentTransaction;
import android.util.Log;
import app.drugs.talksooner.R;
public class BaseContainerFragment extends Fragment {
public void replaceFragment(Fragment fragment, boolean addToBackStack) {
FragmentTransaction transaction = getChildFragmentManager().beginTransaction();
if (addToBackStack) {
transaction.addToBackStack(null);
}
transaction.replace(R.id.container_framelayout, fragment);
transaction.commit();
getChildFragmentManager().executePendingTransactions();
}
public boolean popFragment() {
Log.e("test", "pop fragment: " + getChildFragmentManager().getBackStackEntryCount());
boolean isPop = false;
if (getChildFragmentManager().getBackStackEntryCount() > 0) {
isPop = true;
getChildFragmentManager().popBackStack();
}
return isPop;
}
}
For more specific details find my complete post over here ..
Dynamically changing the fragments inside a fragment tab host?

ViewPagers in a ListView showing blank list items

[EDIT]: Thank you for all the meaningful answers, the problem is now solved, thank to your help. Similar issue: Android: I am unable to have ViewPager WRAP_CONTENT
I'm trying to implement the UI of my app : I want a ListView with a ViewPager in each row.
Here are my files :
MainActivity.java
package com.condi;
import android.app.ListActivity;
import android.os.Bundle;
import android.view.Menu;
public class MainActivity extends ListActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
setListAdapter(new CardListAdapter(this, getFragmentManager()));
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
CardListAdapter.java
package com.condi;
import java.util.List;
import android.app.FragmentManager;
import android.content.Context;
import android.support.v4.view.ViewPager;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
public class CardListAdapter extends BaseAdapter {
private Context context;
private FragmentManager fragmentManager;
private List<Profile> profiles;
CardListAdapter(Context context, FragmentManager fragmentManager) {
this.context = context;
this.fragmentManager = fragmentManager;
this.profiles = new DatabaseHelper(context).getProfiles();
}
#Override
public int getCount() {
return profiles.size();
}
#Override
public Profile getItem(int position) {
return profiles.get(position);
}
#Override
public long getItemId(int position) {
return position;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
convertView = View.inflate(context, R.layout.profile_card, null);
CardPagerAdapter mCardPagerAdapter = new CardPagerAdapter(
fragmentManager);
ViewPager viewPager = (ViewPager) convertView.findViewById(R.id.pager);
viewPager.setAdapter(mCardPagerAdapter);
viewPager.setId(R.id.pager);
return convertView;
}
}
profile_card.xml (issue came from wrap_content).
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="4dp"
android:layout_marginLeft="6dp"
android:layout_marginRight="6dp"
android:layout_marginTop="4dp"
android:background="#drawable/card_background"
android:orientation="vertical" >
<android.support.v4.view.ViewPager
android:id="#+id/pager"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</LinearLayout>
</FrameLayout>
CardPagerAdapter.java
package com.condi;
import android.app.Fragment;
import android.app.FragmentManager;
import android.support.v13.app.FragmentPagerAdapter;
public class CardPagerAdapter extends FragmentPagerAdapter {
public CardPagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int position) {
switch (position) {
case 0:
return new Fragment1();
case 1:
return new Fragment2();
}
return null;
}
#Override
public int getCount() {
return 2;
}
}
Fragment1.java
package com.condi;
import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
public class Fragment1 extends Fragment {
public Fragment1() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.preference_category, container, false);
}
}
Fragment2.java
package com.condi;
import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
public class Fragment2 extends Fragment {
public Fragment2() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.preference_category, container, false);
}
}
The database that furnishes the profiles is working well.
The problem is that I am getting an empty list with the correct number of item, but no ViewPager displayed at all. screenshot of my app
What am I doing wrong ?

Try to change your ViewPager's height in xml. wrap_content does not work.

To make is clear, its a bad practice to use viewpagers inside a list view as this design hits the ui performance. The best way to handle this problem is:
To do manual inflation of viewpagers and add to a layout.
Add a unique id to each viewpager so that it is identified uniquely by the system.
Extend a custom viewpager and onmeasure() measure the child layout inflated at the page selected. You can do this by setting a callback in your custom viewpager and trigger the callback from viewpagers onPageScrolled listener, passing the position to identify the child layout.
In your onMeaure() method measure the child layout height and set it as the viewpagers height using super.onMeasure() passing the newly measured specs.
Key points to make a note of :
N.B. Set a unique id to the viewpager inflated by you.

try this problem in layout height
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginBottom="4dp"
android:layout_marginLeft="6dp"
android:layout_marginRight="6dp"
android:layout_marginTop="4dp"
android:background="#drawable/card_background"
android:orientation="vertical" >
<android.support.v4.view.ViewPager
android:id="#+id/pager"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>
</FrameLayout>

It's a bad practice to use wrap_content for your viewpager's height. You can use match_parent or a static dp for your viewpager's height.
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="4dp"
android:layout_marginLeft="6dp"
android:layout_marginRight="6dp"
android:layout_marginTop="4dp"
android:background="#drawable/card_background"
android:orientation="vertical" >
<android.support.v4.view.ViewPager
android:id="#+id/pager"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>
</FrameLayout>
If it's a must to use wrap_content for your viewpager's height you can override your viewpager's onMeasure() and calculate height. Here's an example below about it.
Android: I am unable to have ViewPager WRAP_CONTENT
I hope this'll help you.

ViewPager doesn’t support wrap_content as it stands now because it doesn’t load all of its children at the same time, meaning it can’t get an appropriate measurement. You must fix View's height in your xml or create a custom ViewPager (read more at here) and use it in your xml

Try using a fixed height ViewPager inside the ListView.ViewPager does not support wrap_content

Can I use setContentView outside the oncreate method?

I have seen many people telling that you can set setContentView outside the oncreate method, but I didn't find anywhere an example. Now when I try to use setContentView, my app just crashes. Here is my source code:
AlarmActivity.java:
package com.alarm.example;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup.LayoutParams;
import android.widget.Button;
import android.widget.RelativeLayout;
public class AlarmActivity extends Activity{
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Button buton = new Button(this);
buton.setId(101);
buton.setText("New alarm");
buton.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.WRAP_CONTENT));
RelativeLayout layout1 = new RelativeLayout(this);
layout1.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));
layout1.addView(buton);
setContentView(layout1);
Button nou =(Button)findViewById(101);
nou.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View v){
New_ala nou1=new New_ala();
nou1.nou_alarma();
}
});
}
}
New_ala.java:
package com.alarm.example;
public class New_ala extends AlarmActivity{
public void nou_alarma() {
setContentView(R.layout.timepicker);
}
}
TimePicker.xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TimePicker
android:id="#+id/timePicker"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<LinearLayout
android:layout_height="wrap_content"
android:layout_width="fill_parent"
android:layout_alignParentBottom="true">
<Button
android:id="#+id/picker_save"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Save">
</Button>
<Button
android:id="#+id/picker_cancel"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Cancel">
</Button>
</LinearLayout>
</LinearLayout>
On more detail, I can use setContentView(R.layout.timepicker) inside the oncreate method without any problems so the problem is that setContentView isn't working properly inside the New_ala.java class. Can anyone help me?
The code after setting the intent:
AlarmActivity:
package com.alarm.example;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
public class AlarmActivity extends Activity{
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
startActivity(new Intent(this, NewAlarmActivity.class));
}
}
NewAlarmActivity:
package com.alarm.example;
import android.os.Bundle;
public class NewAlarmActivity extends AlarmActivity{
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.timepicker);
}
}

You can call setContentView any time you are running on the event (UI) thread. Be aware that when you do, any fields you initialized by calling findViewById will need to be reset.

The best way to do that is to have multiple activities: instead of nou1.nou_alarma();, create an intent and start a new activity with the new layout.
startActivity(new Intent(this, NewAlarmActivity.class));
And in the onCreate method of NewAlarmActivity, set the content view to R.layout.timepicker

The setContentView() method can be called only once per activity. If you want to completely change the layout at some point you should either go for ViewFlipper or have 2 layouts in the activity and show only one of them at given time by calling view.setVisibility(View.GONE); and view.setVisibility(View.VISIBLE); respectively.