Creating a scientific Android app involves designing a user interface (UI) and implementing functionality for scientific calculations, such as arithmetic operations, trigonometric functions, logarithms, exponentials, etc. Below is an example of a simple scientific calculator app in Android using Java and Android Studio.
Steps to Create the App:
- Set up an Android Studio project.
- Design the UI using XML.
- Implement the logic in Java.
1. XML Layout (UI Design)
Create a activity_main.xml file in the res/layout folder:
<?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:padding="16dp">
<!-- Display for input and output -->
<EditText
android:id="@+id/display"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textSize="24sp"
android:inputType="none"
android:focusable="false"
android:clickable="false"
android:text="0"
android:gravity="end"
android:background="@android:color/transparent"
android:padding="8dp" />
<!-- Buttons for scientific operations -->
<GridLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:columnCount="4"
android:rowCount="5">
<!-- Row 1 -->
<Button android:text="sin" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<Button android:text="cos" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<Button android:text="tan" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<Button android:text="√" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<!-- Row 2 -->
<Button android:text="log" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<Button android:text="ln" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<Button android:text="^" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<Button android:text="C" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<!-- Row 3 -->
<Button android:text="7" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<Button android:text="8" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<Button android:text="9" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<Button android:text="/" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<!-- Row 4 -->
<Button android:text="4" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<Button android:text="5" android:onButtonClick="onButtonClick" android:layout_columnWeight="1" />
<Button android:text="6" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<Button android:text="*" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<!-- Row 5 -->
<Button android:text="1" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<Button android:text="2" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<Button android:text="3" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<Button android:text="-" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<!-- Row 6 -->
<Button android:text="0" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<Button android:text="." android:onClick="onButtonClick" android:layout_columnWeight="1" />
<Button android:text="=" android:onClick="onButtonClick" android:layout_columnWeight="1" />
<Button android:text="+" android:onClick="onButtonClick" android:layout_columnWeight="1" />
</GridLayout>
</LinearLayout>
2. Java Code (Logic)
Create the MainActivity.java file in the java/com/example/scientificcalculator folder:
package com.example.scientificcalculator;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import androidx.appcompat.app.AppCompatActivity;
public class MainActivity extends AppCompatActivity {
private EditText display;
private String input = "";
private boolean isResultDisplayed = false;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
display = findViewById(R.id.display);
}
// Handle button clicks
public void onButtonClick(View view) {
String buttonText = ((android.widget.Button) view).getText().toString();
switch (buttonText) {
case "C":
input = "";
break;
case "=":
calculateResult();
isResultDisplayed = true;
break;
case "√":
input = String.valueOf(Math.sqrt(Double.parseDouble(input)));
break;
case "sin":
input = String.valueOf(Math.sin(Math.toRadians(Double.parseDouble(input))));
break;
case "cos":
input = String.valueOf(Math.cos(Math.toRadians(Double.parseDouble(input))));
break;
case "tan":
input = String.valueOf(Math.tan(Math.toRadians(Double.parseDouble(input))));
break;
case "log":
input = String.valueOf(Math.log10(Double.parseDouble(input)));
break;
case "ln":
input = String.valueOf(Math.log(Double.parseDouble(input)));
break;
case "^":
input += "^";
break;
default:
if (isResultDisplayed && !buttonText.matches("[0-9]")) {
input = "";
}
input += buttonText;
isResultDisplayed = false;
break;
}
display.setText(input);
}
// Calculate the result
private void calculateResult() {
try {
// Handle exponentiation (^)
if (input.contains("^")) {
String[] parts = input.split("\\^");
double base = Double.parseDouble(parts[0]);
double exponent = Double.parseDouble(parts[1]);
input = String.valueOf(Math.pow(base, exponent));
} else {
// Evaluate other expressions
input = String.valueOf(eval(input));
}
} catch (Exception e) {
input = "Error";
}
}
// Evaluate mathematical expressions
private double eval(String expression) {
return new Object() {
int pos = -1, ch;
void nextChar() {
ch = (++pos < expression.length()) ? expression.charAt(pos) : -1;
}
boolean eat(int charToEat) {
while (ch == ' ') nextChar();
if (ch == charToEat) {
nextChar();
return true;
}
return false;
}
double parse() {
nextChar();
double x = parseExpression();
if (pos < expression.length()) throw new RuntimeException("Unexpected: " + (char) ch);
return x;
}
double parseExpression() {
double x = parseTerm();
for (; ; ) {
if (eat('+')) x += parseTerm(); // addition
else if (eat('-')) x -= parseTerm(); // subtraction
else return x;
}
}
double parseTerm() {
double x = parseFactor();
for (; ; ) {
if (eat('*')) x *= parseFactor(); // multiplication
else if (eat('/')) x /= parseFactor(); // division
else return x;
}
}
double parseFactor() {
if (eat('+')) return parseFactor(); // unary plus
if (eat('-')) return -parseFactor(); // unary minus
double x;
int startPos = this.pos;
if (eat('(')) { // parentheses
x = parseExpression();
eat(')');
} else if ((ch >= '0' && ch <= '9') || ch == '.') { // numbers
while ((ch >= '0' && ch <= '9') || ch == '.') nextChar();
x = Double.parseDouble(expression.substring(startPos, this.pos));
} else {
throw new RuntimeException("Unexpected: " + (char) ch);
}
return x;
}
}.parse();
}
}
3. Features of the App:
- Basic arithmetic operations (
+,-,*,/). - Scientific functions (
sin,cos,tan,log,ln,√,^). - Clear button (
C) to reset the input. - Real-time display of input and results.
4. Run the App:
- Open the project in Android Studio.
- Connect an Android device or use an emulator.
- Click Run to build and deploy the app.
This is a basic implementation. You can enhance it further by adding more features like history, themes, or unit conversions. Let me know if you need help with any specific feature!
