Slip-8
Q1. Create an Android App with Login Screen. On successful login, gives message go to next
Activity (Without Using Database& use Table Layout).
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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"
tools:context=".MainActivity">
<TableLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="16dp"
app:layout_constraintTop_toTopOf="parent">
<TableRow>
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginEnd="8dp"
android:text="Username"
android:textAppearance="?android:textAppearanceButton"/>
<EditText
android:id="@+id/userinput"
android:layout_width="283dp"
android:layout_height="wrap_content"
android:inputType="text"/>
</TableRow>
<TableRow>
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginEnd="8dp"
android:text="Password"
android:textAppearance="?android:textAppearanceButton"/>
<EditText
android:id="@+id/passinput"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:inputType="textPassword"/>
</TableRow>
<Button
android:id="@+id/loginbutton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Login"/>
</TableLayout>
</androidx.constraintlayout.widget.ConstraintLayout>
-------------------------
MainActivity.java
package com.example.slip8a;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
EditText emailedttxt,passwordedttext;
Button loginButton;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
emailedttxt =findViewById(R.id.userinput);
passwordedttext = findViewById(R.id.passinput);
loginButton=findViewById(R.id.loginbutton);
loginButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
String email = emailedttxt.getText().toString().trim();
String password = passwordedttext.getText().toString().trim();
String constemail = "[email protected]";
String constpassword = "pass";
if(email.isEmpty() || password.isEmpty()){
Toast.makeText(MainActivity.this, "Please Enter Email and Password", Toast.LENGTH_SHORT).show();
} else if (email.equals(constemail) && password.equals(constpassword)) {
// Start the next activity
startActivity(new Intent(MainActivity.this, NextActivity.class));
} else {
Toast.makeText(MainActivity.this, "Email and Password don't match", Toast.LENGTH_SHORT).show();
}
}
});
}
}
-------------------------
activity_next.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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"
tools:context=".NextActivity">
<TextView
android:id="@+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Welcome to Next Activity! You have successfully login!"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
-------------------------
NextActivity.java(No need to edit keep it as it is)
----------------------------------------------------------------------------------------------------------------------------
Q2. Create an android application to demonstrate how to use a service to download a file from the
Internet on click of Download Button. Once done, the service notifies the activity via a broadcast
receiver that the download is complete.
activity_main.xml
<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"
android:padding="16dp"
tools:context=".MainActivity">
<Button
android:id="@+id/btnDownload"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Download File"
android:layout_centerInParent="true"/>
<TextView
android:id="@+id/txtStatus"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@id/btnDownload"
android:layout_marginTop="16dp"/>
</RelativeLayout>
---------------------------
MainActivity.java
package com.example.slip8b;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import androidx.appcompat.app.AppCompatActivity;
public class MainActivity extends AppCompatActivity {
private Button btnDownload;
private TextView txtStatus;
private BroadcastReceiver downloadReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (action != null) {
switch (action) {
case DownloadService.DOWNLOAD_PROGRESS:
String progress = intent.getStringExtra("progress");
txtStatus.setText("Download in progress: " + progress);
break;
case DownloadService.DOWNLOAD_COMPLETE:
txtStatus.setText("Download complete");
break;
}
}
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnDownload = findViewById(R.id.btnDownload);
txtStatus = findViewById(R.id.txtStatus);
btnDownload.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
startDownloadService();
}
});
// Register BroadcastReceiver to receive status from service
IntentFilter filter = new IntentFilter();
filter.addAction(DownloadService.DOWNLOAD_PROGRESS);
filter.addAction(DownloadService.DOWNLOAD_COMPLETE);
registerReceiver(downloadReceiver, filter);
}
@Override
protected void onDestroy() {
super.onDestroy();
unregisterReceiver(downloadReceiver);
}
private void startDownloadService() {
Intent intent = new Intent(this, DownloadService.class);
startService(intent);
}
}
---------------------------
DownloadService.java
package com.example.slip8b;
import android.app.IntentService;
import android.content.Intent;
public class DownloadService extends IntentService {
public static final String DOWNLOAD_PROGRESS = "DOWNLOAD_PROGRESS";
public static final String DOWNLOAD_COMPLETE = "DOWNLOAD_COMPLETE";
public DownloadService() {
super("DownloadService");
}
@Override
protected void onHandleIntent(Intent intent) {
// Simulate file download
for (int i = 1; i <= 5; i++) {
// Update progress every second for demonstration
sendProgressBroadcast(i * 20 + "%");
try {
Thread.sleep(1000); // Simulate 1 second of download time
} catch (InterruptedException e) {
e.printStackTrace();
}
}
// Send broadcast to notify download complete
Intent broadcastIntent = new Intent(DOWNLOAD_COMPLETE);
sendBroadcast(broadcastIntent);
}
private void sendProgressBroadcast(String progress) {
Intent broadcastIntent = new Intent(DOWNLOAD_PROGRESS);
broadcastIntent.putExtra("progress", progress);
sendBroadcast(broadcastIntent);
}
}
-----------------------------------------
AndroidManifest.xml
<manifest xmlns:android="http://schemas.android.com/apk/res/android">
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.BLUETOOTH_CONNECT"/>
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/Theme.Slip8b">
<activity
android:name=".MainActivity"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<service android:name=".DownloadService" />
<receiver
android:name=".DownloadBroadcastReceiver"
android:enabled="true"
android:exported="true">
<intent-filter>
<action android:name="DOWNLOAD_PROGRESS"/>
<action android:name="DOWNLOAD_COMPLETE"/>
</intent-filter>
</receiver>
</application>
</manifest>
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