Android How to call Fragment from my Main Activity

Question

i am very new to android development.

in my case i have one main activity and one fragment created.Main activity as two buttons.

when i click on button, my fragment should load .how can i achieve that?

Mainactivity .XML

<Button
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
    android:text="Fragment 2"
    android:id="@+id/fragment_button_2"
    android:layout_centerVertical="true"
    android:layout_centerHorizontal="true" />

<Button
    style="?android:attr/buttonStyleSmall"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Fragment 1"
    android:id="@+id/fragment_button_1"
    android:layout_above="@+id/fragment_button_2"
    android:layout_alignLeft="@+id/fragment_button_2"
    android:layout_alignStart="@+id/fragment_button_2"
    android:layout_marginBottom="33dp" />
</RelativeLayout>

Main activity .java

package com.bentgeorge.fragment;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity implements    View.OnClickListener{
private Button fragment_btn_1;
private Button fragment_btn_2;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    fragment_btn_1 = (Button) findViewById(R.id.fragment_button_1);
    fragment_btn_2 = (Button) findViewById(R.id.fragment_button_2);


}

@Override
public void onClick(View v) {

Fragment1 frag = new Fragment1();
FragmentManager manager = getSupportFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
transaction.add(R.id.mainlayout,frag,"Test Fragment");
transaction.commit();

}
}

fragment_fragment1.xml

<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.bentgeorge.fragment.Fragment1">

<!-- TODO: Update blank fragment layout -->
<TextView
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="@string/hello_blank_fragment" />

</FrameLayout>

Fragment1.java

package com.bentgeorge.fragment;


import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;


/**
* A simple {@link Fragment} subclass.
*/
public class Fragment1 extends Fragment {


public Fragment1() {
    // Required empty public constructor
}


@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    return inflater.inflate(R.layout.fragment_fragment1, container,  false);
}

}

Not done much codes as i am confused with internet available tutorials.

Please help me to fix this

Thanks & Regards,

Update:

i have done some changes and my fragment is getting loaded now. ut the buttons are still visible . How can i hide the buttons

Answer 1

Updated: Please change your MainActivity as like this:

  public class MainActivity extends AppCompatActivity  {

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            Fragment fragment = new MainFragment();
            getSupportFragmentManager().beginTransaction()
                    .replace(R.id.fragment_frame, fragment, fragment.getClass().getSimpleName()).addToBackStack(null).commit();

        }
    }

Change your activity_main.xml as like this:

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"                
android:id="@+id/fragment_frame"            
android:layout_width="match_parent"
            android:layout_height="match_parent" />

Please create an xml fragment_main.xml:

  <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"                
                android:layout_width="match_parent"
                android:layout_height="match_parent" >
    <Button
     android:layout_width="wrap_content"
     android:layout_height="wrap_content"
        android:text="Fragment 2"
        android:id="@+id/fragment_button_2"
        android:layout_centerVertical="true"
        android:layout_centerHorizontal="true" />

    <Button
        style="?android:attr/buttonStyleSmall"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Fragment 1"
        android:id="@+id/fragment_button_1"
        android:layout_above="@+id/fragment_button_2"
        android:layout_alignLeft="@+id/fragment_button_2"
        android:layout_alignStart="@+id/fragment_button_2"
        android:layout_marginBottom="33dp" />
    </RelativeLayout>

Also create a fragment as MainFragment:

public class MainFragment extends Fragment implements View.OnClickListener{
     private Button fragment_btn_1;
        private Button fragment_btn_2;

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_main, container, false);
        fragment_btn_1 = (Button) view.findViewById(R.id.fragment_button_1);
            fragment_btn_2 = (Button) view.findViewById(R.id.fragment_button_2);
            fragment_btn_1.setOnClickListener(this);
            fragment_btn_2.setOnClickListener(this);
        return view;
    }
@Override
        public void onClick(View v) {
            switch (v.getId()) {
                case R.id.fragment_button_1:
                    Fragment fragment1 = new Fragment1();
                    moveToFragment(fragment1);
                    break;
                case R.id.fragment_button_2:
                    Fragment fragment2 = new Fragment2();
                    moveToFragment(fragment2);
                    break;
            }
        }

        private void moveToFragment(Fragment fragment) {
            getSupportFragmentManager().beginTransaction()
                    .replace(R.id.fragment_frame, fragment, fragment.getClass().getSimpleName()).addToBackStack(null).commit();

        }
}

Hope this will helps you. If you had any queries, let me know.

Answer 2

in you onClick() method -

if(v.getId()==R.id.fragment_button_1){
getActivity().getSupportFragmentManager().beginTransaction()
                            .add(R.id.fragment_frame, new Fragment1(), "createPost").addToBackStack(null).commit();
              }

where R.id.fragment_frame - rootContainer Id rootView in MainActivity.java

you should use Framelayout for placing fragment in activity.

like below - activity_layout.xml -

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/root_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.myapplication.Activities.TestActivity">

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="40dp"
        android:orientation="vertical">

        <Button
            android:id="@+id/button1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true"
            android:text="Button 1" />

        <Button
            android:id="@+id/button2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@id/button1"
            android:layout_centerHorizontal="true"
            android:text="Button 1" />

    </LinearLayout>

</FrameLayout>

and your activity - MainActivity.java

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;


public class TestActivity extends AppCompatActivity implements View.OnClickListener{

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_test);

        Button button1 = (Button) findViewById(R.id.button1);
        Button button2 = (Button) findViewById(R.id.button2);
        button1.setOnClickListener(this);
        button2.setOnClickListener(this);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_test, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }

    @Override
    public void onClick(View v) {
        if (v.getId() == R.id.button1){
            getSupportFragmentManager().beginTransaction().
                    replace(R.id.root_layout, new Fragment1()).commit();
        }
    }
}

btw your fragment looks good. hope it will help you.