Question

I am learning android and so I wrote the following code for learning ScrollView and creating multiple linearlayouts inside a linearlayout. I have created a menu to launch different activities, but the problem is when I click the class associated with this xml file, the new class (activity) doesn’t show up on the screen. What can be the problem and how can I fix it? here is the code:

<?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"
android:weightSum="100"
android:padding="25dp" >

<ScrollView 
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:layout_weight="30"
>

<LinearLayout 
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
>
<TextView
    android:id="@+id/textView1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Name" />

<EditText
    android:id="@+id/editText1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:ems="10" >

    <requestFocus />
</EditText>

<TextView
    android:id="@+id/textView2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Age" />

<EditText
    android:id="@+id/editText2"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:ems="10" />

<TextView
    android:id="@+id/textView3"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Email Address" />

<EditText
    android:id="@+id/editText3"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:ems="10" />

<TextView
    android:id="@+id/textView4"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Subject" />

<EditText
    android:id="@+id/editText4"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:ems="10" />

<TextView
    android:id="@+id/textView5"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Phone No." />

<EditText
    android:id="@+id/editText5"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:ems="10" />

<TextView
    android:id="@+id/textView6"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Your Message" />

<EditText
    android:id="@+id/editText6"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:ems="10" />
</LinearLayout>
</ScrollView>

<LinearLayout 
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    android:layout_weight="40">
<Button
    android:id="@+id/button1"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:paddingTop="20dp"
    android:text="Email" />
</LinearLayout>

<LinearLayout 
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:layout_weight="30"
    android:orientation="vertical">
<AnalogClock
    android:id="@+id/analogClock1"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" />
</LinearLayout>

The class Email code:

package com.umer.practice2;

 import android.app.Activity;
import android.os.Bundle;
import android.widget.AnalogClock;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class Email extends Activity {

TextView t1,t2,t3,t4,t5,t6;
EditText e1,e2,e3,e4,e5,e6;
Button butn;
AnalogClock clock;
@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.email);
    initializeviews();
}

private void initializeviews() {
    // TODO Auto-generated method stub
    t1= (TextView) findViewById(R.id.textView1);
    t2= (TextView) findViewById(R.id.textView2);
    t3= (TextView) findViewById(R.id.textView3);
    t4= (TextView) findViewById(R.id.textView4);
    t5= (TextView) findViewById(R.id.textView5);
    t6= (TextView) findViewById(R.id.textView6);
    e1= (EditText) findViewById(R.id.editText1);
    e2= (EditText) findViewById(R.id.editText2);
    e3= (EditText) findViewById(R.id.editText3);
    e4= (EditText) findViewById(R.id.editText4);
    e5= (EditText) findViewById(R.id.editText5);
    e6= (EditText) findViewById(R.id.editText6);
    butn=(Button) findViewById(R.id.button1);
    clock= (AnalogClock) findViewById(R.id.analogClock1);
}


}

Answer 1

Did you added the activity in AndroidManifest.xml? Every activity need to be added into the manifest file.

for example:

 <activity android:name=".HelloGoogleMaps" android:label="@string/app_name"/>