add view controller which can detect keyboard opening

navigation/src/main/java/ru/touchin/roboswag/components/navigation/activities/BaseActivity.kt

@@ -22,6 +22,7 @@ package ru.touchin.roboswag.components.navigation.activities
 import android.content.Intent
 import android.os.Bundle
 import androidx.appcompat.app.AppCompatActivity
+import ru.touchin.roboswag.components.navigation.keyboard_resizeable.KeyboardBehaviorDetector
 import ru.touchin.roboswag.components.navigation.viewcontrollers.LifecycleLoggingObserver
 import ru.touchin.roboswag.core.log.Lc
 import ru.touchin.roboswag.core.log.LcGroup
@@ -34,6 +35,8 @@ abstract class BaseActivity : AppCompatActivity() {
 
     private val onBackPressedListeners = ArrayList<OnBackPressedListener>()
 
+    open val keyboardBehaviorDetector: KeyboardBehaviorDetector? = null
+
     init {
         lifecycle.addObserver(LifecycleLoggingObserver())
     }

navigation/src/main/java/ru/touchin/roboswag/components/navigation/keyboard_resizeable/KeyboardBehaviorDetector.kt

@@ -0,0 +1,64 @@
+package ru.touchin.roboswag.components.navigation.keyboard_resizeable
+
+import android.graphics.Rect
+import android.view.View
+import android.view.ViewGroup
+import ru.touchin.roboswag.components.navigation.activities.BaseActivity
+
+// The workaround forces an activity to resize when keyboard appears in the full-screen mode
+class KeyboardBehaviorDetector(
+        activity: BaseActivity,
+        fragmentContainerId: Int
+) {
+
+    private val contentContainer = activity.findViewById(android.R.id.content) as ViewGroup
+    private val fragmentContainer = activity.findViewById(fragmentContainerId) as ViewGroup
+    private lateinit var rootView: View
+    private val listener = { possiblyResizeChildOfContent() }
+
+    private var keyboardHideListener: (() -> Unit)? = null
+    private var keyboardShowListener: ((Int) -> Unit)? = null
+
+    fun setKeyboardHideListener(listener: () -> Unit) {
+        keyboardHideListener = listener
+    }
+
+    fun removeKeyboardHideListener() {
+        keyboardHideListener = null
+    }
+
+    fun setKeyboardShowListener(listener: (Int) -> Unit) {
+        keyboardShowListener = listener
+    }
+
+    fun removeKeyboardShowListener() {
+        keyboardShowListener = null
+    }
+
+    // Call this in "onResume()" of a fragment
+    fun startDetection() {
+
+        rootView = fragmentContainer.getChildAt(0)
+
+        contentContainer.viewTreeObserver.addOnGlobalLayoutListener(listener)
+    }
+
+    // Call this in "onPause()" of a fragment
+    fun stopDetection() {
+        contentContainer.viewTreeObserver.removeOnGlobalLayoutListener(listener)
+    }
+
+    //https://stackoverflow.com/questions/2150078/how-to-check-visibility-of-software-keyboard-in-android?rq=1
+    private fun possiblyResizeChildOfContent() {
+        val rect = Rect()
+        rootView.getWindowVisibleDisplayFrame(rect)
+        val height = rootView.context.resources.displayMetrics.heightPixels
+        val diff = height - rect.bottom
+
+        if (diff > rootView.rootView.height / 4) {
+            keyboardShowListener?.invoke(diff)
+        } else {
+            keyboardHideListener?.invoke()
+        }
+    }
+}

navigation/src/main/java/ru/touchin/roboswag/components/navigation/keyboard_resizeable/KeyboardResizeableViewController.kt

@@ -0,0 +1,82 @@
+package ru.touchin.roboswag.components.navigation.keyboard_resizeable
+
+import android.os.Build
+import android.os.Parcelable
+import androidx.annotation.LayoutRes
+import ru.touchin.roboswag.components.navigation.activities.BaseActivity
+import ru.touchin.roboswag.components.navigation.activities.OnBackPressedListener
+import ru.touchin.roboswag.components.navigation.viewcontrollers.ViewController
+import ru.touchin.roboswag.components.utils.UiUtils
+
+abstract class KeyboardResizeableViewController<TActivity : BaseActivity, TState : Parcelable>(
+        @LayoutRes layoutRes: Int,
+        creationContext: CreationContext
+) : ViewController<TActivity, TState>(
+        creationContext,
+        layoutRes
+) {
+    init {
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT_WATCH) {
+            creationContext.container?.requestApplyInsets()
+        }
+    }
+
+    private var keyboardIsVisible: Boolean = false
+
+    private val keyboardHideListener = OnBackPressedListener {
+        if (keyboardIsVisible) {
+            UiUtils.OfViews.hideSoftInput(activity)
+            true
+        } else {
+            false
+        }
+    }
+
+    private var isHideKeyboardOnBackEnabled = false
+
+    protected open fun onKeyboardShow(diff: Int = 0) {}
+
+    protected open fun onKeyboardHide() {}
+
+    protected fun hideKeyboardOnBackPressed() {
+        isHideKeyboardOnBackEnabled = true
+    }
+
+    override fun onResume() {
+        super.onResume()
+        if (isHideKeyboardOnBackEnabled) activity.addOnBackPressedListener(keyboardHideListener)
+    }
+
+    override fun onPause() {
+        super.onPause()
+        if (isHideKeyboardOnBackEnabled) activity.removeOnBackPressedListener(keyboardHideListener)
+    }
+
+    override fun onStart() {
+        super.onStart()
+        activity.keyboardBehaviorDetector?.apply {
+            setKeyboardHideListener {
+                if (keyboardIsVisible) {
+                    onKeyboardHide()
+                }
+                keyboardIsVisible = false
+            }
+            setKeyboardShowListener { diff ->
+                if (!keyboardIsVisible) {
+                    onKeyboardShow(diff)
+                }
+                keyboardIsVisible = true
+            }
+            startDetection()
+        }
+    }
+
+    override fun onStop() {
+        super.onStop()
+        activity.keyboardBehaviorDetector?.apply {
+            removeKeyboardHideListener()
+            removeKeyboardShowListener()
+            stopDetection()
+        }
+    }
+}