Add feature pinch to zoom

app/src/main/java/com/lagradost/cloudstream3/widget/ZoomLayout.kt

@@ -0,0 +1,97 @@
+package com.lagradost.cloudstream3.widget
+
+import android.content.Context
+import android.graphics.Canvas
+import android.util.AttributeSet
+import android.view.MotionEvent
+import android.view.ScaleGestureDetector
+import android.widget.FrameLayout
+import android.animation.ValueAnimator
+import androidx.interpolator.view.animation.FastOutSlowInInterpolator
+
+/**
+ *This is a container that lets the user pinch to zoom its entire contents
+ */
+class ZoomLayout @JvmOverloads constructor( //Why not
+    context: Context,
+    attrs: AttributeSet? = null
+) : FrameLayout(context, attrs), ScaleGestureDetector.OnScaleGestureListener {
+
+    private var scaleFactor = 1f //current scale factor
+
+    //pivot points
+    private var focusX = 0f
+    private var focusY = 0f
+
+    //the gesture detector
+    private val detector = ScaleGestureDetector(context, this)
+
+    //animator that resets scaleFactor/focus back to defaults
+    private val resetAnimator = ValueAnimator.ofFloat(0f,1f).apply {
+        interpolator = FastOutSlowInInterpolator()
+        duration = 300L
+        addUpdateListener { anim ->
+            // anim.animatedValue will go from 1f → 0f
+            val fraction = anim.animatedFraction
+            // lerp scaleFactor from current → 1f
+            scaleFactor = lerp(scaleFactorStart, 1f, fraction)
+            // lerp focus back to center
+            focusX = lerp(focusXStart, width / 2f, fraction)
+            focusY = lerp(focusYStart, height / 2f, fraction)
+            invalidate()
+        }
+    }
+
+
+    private var scaleFactorStart = 1f
+    private var focusXStart = 0f
+    private var focusYStart = 0f
+
+    override fun onInterceptTouchEvent(ev: MotionEvent): Boolean {
+        //lets the detector see all touches
+        detector.onTouchEvent(ev)
+        //if we're in a scaling gesture, intercept so children don't steal it
+        return detector.isInProgress || super.onInterceptTouchEvent(ev)
+    }
+
+    override fun onTouchEvent(ev: MotionEvent): Boolean {
+        detector.onTouchEvent(ev)
+        //consume all touch events to keep the zooming based on the current view
+        return true
+    }
+
+    override fun dispatchDraw(canvas: Canvas) {
+        //before drawing children, scale the canvas around the pivot point
+        canvas.save()
+        canvas.translate(focusX, focusY)
+        canvas.scale(scaleFactor, scaleFactor)
+        canvas.translate(-focusX, -focusY)
+        super.dispatchDraw(canvas)
+        canvas.restore()
+    }
+
+    //scaleGestureDetector callbacks
+    override fun onScaleBegin(detector: ScaleGestureDetector) = true
+
+    override fun onScale(detector: ScaleGestureDetector): Boolean {
+        // Update scale and pivot
+        scaleFactor = (scaleFactor * detector.scaleFactor).coerceIn(0.5f, 3.0f)
+        focusX = detector.focusX
+        focusY = detector.focusY
+        // Tell Android we need to redraw
+        invalidate()
+        return true
+    }
+
+
+    //we now use it for a cleaner approach since it already works
+    override fun onScaleEnd(detector: ScaleGestureDetector) {
+        scaleFactorStart = scaleFactor
+        focusXStart = focusX
+        focusYStart = focusY
+        resetAnimator.start()
+    }
+
+    //simple helper
+    private fun lerp(a: Float, b: Float, t: Float): Float = a + (b - a) * t
+}

app/src/main/res/layout/activity_main.xml

@@ -1,4 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
+<com.lagradost.cloudstream3.widget.ZoomLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:id="@+id/zoomRoot"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent">
+
 <FrameLayout 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"
@@ -82,4 +88,5 @@
                 tools:ignore="FragmentTagUsage" />
         </LinearLayout>
     </androidx.constraintlayout.widget.ConstraintLayout>
-</FrameLayout>
+</FrameLayout>
+</com.lagradost.cloudstream3.widget.ZoomLayout>