Multiple Activities in Android Studio

Question

I'm new to Android. I'm trying to test 2 Activities in my project where when I click on a button in my first Activity, it should take me to the second Activity. Here I have given a click event to my button but when I run the project, I'm unable to see anything, its just a blank screen. What am I missing ?

public class MainActivity extends ActionBarActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }


    @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_main, 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);
    }

    public void onAddCLick(View view) {
        Intent TaskIntent = new Intent(this,SecondScreen.class);

        startActivity(TaskIntent);
    }
}

This is the second activity :-

public class SecondScreen extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.second_layout);

        Intent task = getIntent();
    }

    public void cancl_btn(View view) {
        Intent goBack = getIntent();
        finish();
    }
}

This is activity_main.xml :-

<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
android:gravity="left"
tools:context=".MainActivity">

<LinearLayout
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="horizontal">

    <ListView
        android:layout_width="wrap_content"
        android:layout_height="516dp"
        android:id="@+id/theListView">

    </ListView>

</LinearLayout>

<LinearLayout
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="horizontal">

    <ImageButton
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:background="@drawable/add_task"
        android:onClick="onAddCLick"/>

    <ImageButton
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:background="@drawable/setloc"
        android:onClick="onMapbtnClck"/>

    <ImageButton
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:background="@drawable/settings"
        android:onClick="onSetngClck"/>

</LinearLayout>

This is second_layout.xml :-

<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
android:gravity="left">

<EditText
    android:layout_width="364dp"
    android:layout_height="wrap_content"
    android:id="@+id/task_name_edit_txt"
    android:text="Enter your Details here" />

<LinearLayout
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="horizontal">

<TextView
    android:layout_width="250dp"
    android:layout_height="wrap_content"
    android:text="Set Location"
    android:id="@+id/textView" />
<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/Set_loc_btn"
    android:onClick="set_usr_loc"/>

</LinearLayout>

<LinearLayout
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="horizontal">

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/Add_task_btn"
        android:onClick="add_usr_tsk_btn"/>

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/cancel_btn"
        android:onClick="cancl_btn"/>
    </LinearLayout>


</LinearLayout>

Answer 1

by assuming that you have posted the complete XML file of the second layout,, I tried running it on my android studio and as you can see in the xml file itself you are missing lot of information in it,,,

1. you need to define the schema as you have done in the first xml and
2. the < EditText > tag cannot be outside a container, you need to place it inside the container, that is, inside any kind of layout (linear, relative etc)..

if the issue is with the xml file then modifying it as per above two points will solve your problem,, hope this helps

Answer 2

Use this code:

In first activity:

public void onAddCLick(View view) {
   Intent TaskIntent = new 
   Intent(MainActivity.this,SecondScreen.class); 
   startActivity(TaskIntent);
}

In second Activity:

   public void cancl_btn(View view) {
      Intent goBack =new 
      Intent(SecondScreen.this,MainActivity.class);   
      startActivity(goBack);
    }