Updated on 2026-08-14

app/src/main/java/com/tangem/tap/common/KeyboardObserver.kt

@@ -0,0 +1,61 @@
+package com.tangem.tap.common
+
+import android.app.Activity
+import android.graphics.Rect
+import android.util.DisplayMetrics
+import android.view.ViewTreeObserver.OnGlobalLayoutListener
+import kotlin.math.absoluteValue
+
+class KeyboardObserver(activity: Activity) {
+
+    private val decorView = activity.window.decorView
+    private val windowManager = activity.windowManager
+    private val originalWindowHeight: Int = getWindowHeight()
+    private val onGlobalLayoutListener: OnGlobalLayoutListener = OnGlobalLayoutListener { onGlobalLayout() }
+
+    private var onKeyboardListener: ((Boolean) -> Unit)? = null
+    private var lastIsShow = false
+    private var lastWindowHeight = getWindowHeight()
+
+    fun registerListener(listener: (Boolean) -> Unit) {
+        decorView.viewTreeObserver.addOnGlobalLayoutListener(onGlobalLayoutListener)
+        onKeyboardListener = listener
+    }
+
+    fun unregisterListener() {
+        decorView.viewTreeObserver.removeOnGlobalLayoutListener(onGlobalLayoutListener)
+        onKeyboardListener = null
+    }
+
+    private fun getWindowHeight() = Rect().apply { decorView.getWindowVisibleDisplayFrame(this) }.bottom
+
+    private fun onGlobalLayout() {
+        val currentWindowHeight = getWindowHeight()
+        if (isSoftKeyChanged()) {
+            lastWindowHeight = currentWindowHeight
+            return
+        }
+
+        lastWindowHeight = currentWindowHeight
+        val isShow = originalWindowHeight != currentWindowHeight
+        if (lastIsShow == isShow) return
+
+        lastIsShow = isShow
+        onKeyboardListener?.invoke(isShow)
+    }
+
+    private fun isSoftKeyChanged() = ((lastWindowHeight - getWindowHeight()).absoluteValue) == getSoftKeyButtonHeight()
+
+    private fun getSoftKeyButtonHeight(): Int {
+        val applicationDisplayHeight = DisplayMetrics().apply {
+            windowManager.defaultDisplay.getMetrics(this)
+        }.heightPixels
+
+        val realDisplayHeight = DisplayMetrics().apply {
+            windowManager.defaultDisplay.getRealMetrics(this)
+        }.heightPixels
+
+        return realDisplayHeight - applicationDisplayHeight
+    }
+
+}