Program Android: Membuat Login Dengan Kotlin

Pengantar

 Apa anda sudah membahas sebebelumnya tentang Perbabangan, Sekarang mari kita praktekkan di dalam kasus pembuatan login:

    Buatlah projek baru dengan nama form_login.

Buat activity varu dengan cara klik kanan pada App-> New->Activity->Empty Views Activity dan beri nama "Home".

Buka Activity_Main dan Buatlah user Interface seperti berikut:

<?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"
    android:padding="15dp"
    tools:context=".MainActivity">

    <View
        android:id="@+id/view"
        android:layout_width="wrap_content"
        android:layout_height="150dp"
        android:background="#6FA8D6"
        tools:layout_editor_absoluteX="6dp"
        tools:layout_editor_absoluteY="4dp" />

    <TextView
        android:id="@+id/textView"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="44dp"
        android:text="SELAMAT DATANG"
        android:textAlignment="center"
        android:textColor="#D30B0B"
        android:textSize="40sp"
        app:layout_constraintTop_toTopOf="parent"
        tools:layout_editor_absoluteX="0dp" />

    <TextView
        android:id="@+id/textView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="40dp"
        android:background="#43DA1B"
        android:padding="10dp"
        android:text="Silakah Login"
        android:textColor="#FCFCFC"
        android:textSize="24sp"
        android:textStyle="bold"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.498"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textView" />

    <EditText
        android:id="@+id/txtEdit"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="48dp"
        android:ems="10"
        android:hint="Input Username"
        android:inputType="text"
        app:layout_constraintTop_toBottomOf="@+id/textView2"
        tools:layout_editor_absoluteX="16dp" />

    <EditText
        android:id="@+id/txtPassword"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="28dp"
        android:ems="10"
        android:hint="Password"
        android:inputType="textPassword"
        app:layout_constraintTop_toBottomOf="@+id/txtEdit"
        tools:layout_editor_absoluteX="16dp" />

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="56dp"
        android:onClick="Login"
        android:text="Log In"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.105"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/txtPassword" />
    
</androidx.constraintlayout.widget.ConstraintLayout>

Buat script programnya:

package com.example.mi_2

import android.content.Intent
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.view.View
import android.widget.EditText
import android.widget.Toast

class MainActivity : AppCompatActivity() {
    val User = "user"
    val Pass = "user"

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
    }

    fun Login(view: View) {
        val user = findViewById<EditText>(R.id.txtEdit)
        val pass = findViewById<EditText>(R.id.txtPassword)

        val getUser = user.getText().toString()
        val getPass = pass.getText().toString()

        //cek user
        if(User.equals(getUser)){
            //cek pass
            if(Pass.equals(getPass)){
                //Masuk ke home
                val i = Intent(this, Home::class.java)
                startActivity(i)
            }else{
                Toast.makeText(this, "Password Salah", Toast.LENGTH_SHORT).show()
            }
        }else{
            Toast.makeText(this, "User Salah", Toast.LENGTH_SHORT).show()
        }
    }
}

Terakhir jalankan progam.