Android | Display multiplication table of a number - GeeksforGeeks

07 Dec, 2021
Given a number, the task is to display the multiplication table of this number using the Android App.
Steps to build app:
STEP-1: Open activity_main.xml file and add TextView, EditText, and a Button
STEP-2: Assign ID to each component
STEP-3: Now, open up the MainActivity file and declare the variables.
STEP-4: Read the values entered in the EditText boxes using an id that has been set in the XML code above.
STEP-5: Add a click listener to the Add button
STEP-6: When the Add button has been clicked we need to Multiply the values and store it in Buffer
STEP-7: Then show the resultant output in the TextView by setting the buffer in the TextView.
Implementation:
Filename: activity_main.xml
XML
<!-- First make the layout file xml and add button, edit text, text view --> <?xml version="1.0" encoding="utf-8"?><android.support.constraint.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"    tools:layout_editor_absoluteY="25dp">     <!-- Add the button for run table logic and print result-->    <!-- give id "button"-->    <Button        android:id="@+id/button"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_marginTop="16dp"        android:text="TABLE"        app:layout_constraintEnd_toEndOf="parent"        app:layout_constraintStart_toEndOf="@+id/editText"        app:layout_constraintTop_toTopOf="parent" />     <!-- Text view for result view-->    <!-- give the id TextView-->    <TextView        android:id="@+id/textView"        android:layout_width="0dp"        android:layout_height="0dp"        android:layout_marginBottom="18dp"        android:layout_marginEnd="36dp"        android:layout_marginLeft="36dp"        android:layout_marginRight="36dp"        android:layout_marginStart="36dp"        android:textColor="@color/colorPrimary"        app:layout_constraintBottom_toBottomOf="parent"        app:layout_constraintEnd_toEndOf="parent"        app:layout_constraintStart_toStartOf="parent"        app:layout_constraintTop_toBottomOf="@+id/editText" />     <!-- edit Text for take input from user-->    <!-- give the id editText-->    <EditText        android:id="@+id/editText"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_marginBottom="20dp"        android:layout_marginEnd="9dp"        android:layout_marginRight="9dp"        android:layout_marginTop="16dp"        android:ems="10"        android:inputType="number"        app:layout_constraintBottom_toTopOf="@+id/textView2"        app:layout_constraintEnd_toStartOf="@+id/button"        app:layout_constraintHorizontal_chainStyle="packed"        app:layout_constraintStart_toStartOf="parent"        app:layout_constraintTop_toTopOf="parent"        tools:ignore="UnknownId" /></android.support.constraint.ConstraintLayout>
Filename: MainActivity.Java
Java
// Build the java logic for multiplication table// using button, text view, edit text package com.example.windows10.table; import android.app.Dialog;import android.content.Intent;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.view.View;import android.widget.Button;import android.widget.EditText;import android.widget.TextView; public class MainActivity    extends AppCompatActivity    implements View.OnClickListener {     // define the global variable     // variable number1, number2 for input input number    // Add_button, result textView     EditText editText;    Button button;    TextView result;    int ans = 0;     protected void onCreate(Bundle savedInstanceState)    {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);         // by ID we can use each component        // whose id is assigned in the XML file         editText = (EditText)findViewById(R.id.editText);        button = (Button)findViewById(R.id.button);        result = (TextView)findViewById(R.id.textView);         // set clickListener on button        button.setOnClickListener(this);    }     @Override    public void onClick(View v)    {         switch (v.getId()) {         case R.id.button:            StringBuffer buffer = new StringBuffer();            int res;             // get the input number from editText            String fs = editText.getText().toString();             // convert it to integer            int n = Integer.parseInt(fs);             // build the logic for table            for (int i = 1; i <= 10; i++) {                ans = (i * n);                buffer.append(n + " X " + i                              + " = " + ans + "\n\n");            }             // set the buffer textview            result.setText(buffer);            break;        }    }}
Output: 
 
kapoorsagar226
surindertarika1234
android
Java
Java
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