AIDE Tutorial - 58.1 Call App with EditText

AIDE Tutorial - 58.1 Call App with EditText
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<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <EditText
android:id="@+id/mainEditText"
android:inputType="number"
android:hint="Enter phone number here"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />

<Button
android:onClick="call"
android:text="Call"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>

MainActivity.java
package com.kcgroup.callapp;

import android.app.*;
import android.os.*;
import android.widget.*;
import android.view.*;
import android.content.*;
import android.net.*;

public class MainActivity extends Activity
{EditText et;
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
et=(EditText)findViewById(R.id.mainEditText);

    }
public void call(View v){
String st=et.getText().toString();
Intent in=new Intent(Intent.ACTION_CALL,Uri.parse("tel:"+st));
startActivity(in);
}
}
Androidmanifest.xml
<uses-permission android:name="android.permission.CALL_PHONE"/>

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