পূর্ব প্রস্তুতি
এই উদাহরণটি GestureDetector ব্যবহার করে স্ক্রিনে свайপ জেসচারের দিক (বাম, ডান, উপরে, নিচে) সনাক্ত করার পদ্ধতি দেখায়।
ধাপ ১: নতুন প্রজেক্ট তৈরি করুন
Android Studio-তে File → New Project নির্বাচন করুন।
ধাপ ২: activity_main.xml লেআউট
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="https://schemas.android.com/apk/res/android"
android:id="@+id/relativeLayout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="@+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_marginTop="70dp"
android:background="#008080"
android:padding="5dp"
android:text="TutorialsPoint"
android:textColor="#fff"
android:textSize="24sp"
android:textStyle="bold" />
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:text="Swipe to Detect swipe Event"
android:textAlignment="center"
android:textColor="@android:color/holo_purple"
android:textSize="24sp"
android:textStyle="bold" />
</RelativeLayout>
ধাপ ৩: MainActivity.kt-এ сваইপ লিসেনার ইমপ্লিমেন্ট করুন
import android.content.Context
import android.os.Bundle
import android.view.GestureDetector
import android.view.MotionEvent
import android.view.View
import android.widget.Toast
import androidx.appcompat.app.AppCompatActivity
import kotlin.math.abs
class MainActivity : AppCompatActivity() {
private var onSwipeTouchListener: OnSwipeTouchListener? = null
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
title = "KotlinApp"
onSwipeTouchListener = OnSwipeTouchListener(this, findViewById(R.id.relativeLayout))
}
inner class OnSwipeTouchListener internal constructor(ctx: Context, mainView: View) : View.OnTouchListener {
private val gestureDetector: GestureDetector
private var context: Context
private lateinit var onSwipe: OnSwipeListener
init {
gestureDetector = GestureDetector(ctx, GestureListener())
mainView.setOnTouchListener(this)
context = ctx
}
override fun onTouch(v: View, event: MotionEvent): Boolean {
return gestureDetector.onTouchEvent(event)
}
companion object {
private const val SWIPE_THRESHOLD = 100
private const val SWIPE_VELOCITY_THRESHOLD = 100
}
inner class GestureListener : GestureDetector.SimpleOnGestureListener() {
override fun onDown(e: MotionEvent): Boolean = true
override fun onFling(e1: MotionEvent, e2: MotionEvent, velocityX: Float, velocityY: Float): Boolean {
var result = false
try {
val diffY = e2.y - e1.y
val diffX = e2.x - e1.x
if (abs(diffX) > abs(diffY)) {
// Horizontal swipe
if (abs(diffX) > SWIPE_THRESHOLD && abs(velocityX) > SWIPE_VELOCITY_THRESHOLD) {
if (diffX > 0) onSwipeRight() else onSwipeLeft()
result = true
}
} else if (abs(diffY) > SWIPE_THRESHOLD && abs(velocityY) > SWIPE_VELOCITY_THRESHOLD) {
// Vertical swipe
if (diffY > 0) onSwipeBottom() else onSwipeTop()
result = true
}
} catch (exception: Exception) {
exception.printStackTrace()
}
return result
}
}
internal fun onSwipeRight() {
Toast.makeText(context, "Swiped Right", Toast.LENGTH_SHORT).show()
onSwipe.swipeRight()
}
internal fun onSwipeLeft() {
Toast.makeText(context, "Swiped Left", Toast.LENGTH_SHORT).show()
onSwipe.swipeLeft()
}
internal fun onSwipeTop() {
Toast.makeText(context, "Swiped Up", Toast.LENGTH_SHORT).show()
onSwipe.swipeTop()
}
internal fun onSwipeBottom() {
Toast.makeText(context, "Swiped Down", Toast.LENGTH_SHORT).show()
onSwipe.swipeBottom()
}
internal interface OnSwipeListener {
fun swipeRight()
fun swipeTop()
fun swipeBottom()
fun swipeLeft()
}
}
}
ধাপ ৪: AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="https://schemas.android.com/apk/res/android"
package="com.example.swipedetection">
<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/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
টেস্টিং
অ্যাপ চালান এবং স্ক্রিনে বাম, ডান, উপরে, নিচে сваইপ করুন। টোস্ট মেসেজে сваইপের দিক দেখাবে।