Added layout behavior to dismiss toolbars when scrolling

2025-09-06 06:36:58 +00:00 · 2019-10-16 16:08:07 +02:00
parent 51247d36c5
commit 2daa131fb2
4 changed files with 140 additions and 1 deletions
@@ -0,0 +1,130 @@
+package com.topjohnwu.magisk.utils
+
+import android.animation.TimeInterpolator
+import android.view.View
+import android.view.ViewGroup
+import android.view.ViewPropertyAnimator
+import androidx.annotation.Dimension
+import androidx.coordinatorlayout.widget.CoordinatorLayout
+import androidx.core.view.ViewCompat
+import com.google.android.material.animation.AnimationUtils
+import com.google.android.material.behavior.HideBottomViewOnScrollBehavior
+
+class HideTopViewOnScrollBehavior<V : View> : HideBottomViewOnScrollBehavior<V>() {
+
+    companion object {
+        private const val STATE_SCROLLED_DOWN = 1
+        private const val STATE_SCROLLED_UP = 2
+    }
+
+    private var height = 0
+    private var currentState = STATE_SCROLLED_UP
+    private var additionalHiddenOffsetY = 0
+    private var currentAnimator: ViewPropertyAnimator? = null
+
+    override fun onLayoutChild(
+        parent: CoordinatorLayout,
+        child: V,
+        layoutDirection: Int
+    ): Boolean {
+        val paramsCompat = child.layoutParams as ViewGroup.MarginLayoutParams
+        height = child.measuredHeight + paramsCompat.topMargin
+        return super.onLayoutChild(parent, child, layoutDirection)
+    }
+
+    /**
+     * Sets an additional offset for the y position used to hide the view.
+     *
+     * @param child the child view that is hidden by this behavior
+     * @param offset the additional offset in pixels that should be added when the view slides away
+     */
+    override fun setAdditionalHiddenOffsetY(child: V, @Dimension offset: Int) {
+        additionalHiddenOffsetY = offset
+
+        if (currentState == STATE_SCROLLED_DOWN) {
+            child.translationY = (height + additionalHiddenOffsetY).toFloat()
+        }
+    }
+
+    override fun onStartNestedScroll(
+        coordinatorLayout: CoordinatorLayout,
+        child: V,
+        directTargetChild: View,
+        target: View,
+        nestedScrollAxes: Int
+    ) = nestedScrollAxes == ViewCompat.SCROLL_AXIS_VERTICAL
+
+    override fun onNestedScroll(
+        coordinatorLayout: CoordinatorLayout,
+        child: V,
+        target: View,
+        dxConsumed: Int,
+        dyConsumed: Int,
+        dxUnconsumed: Int,
+        dyUnconsumed: Int
+    ) {
+        when {
+            dyConsumed > 0 -> slideUp(child)
+            dyConsumed < 0 -> slideDown(child)
+        }
+    }
+
+    /**
+     * Perform an animation that will slide the child from it's current position to be totally on the
+     * screen.
+     */
+    override fun slideDown(child: V) {
+        if (currentState == STATE_SCROLLED_UP) {
+            return
+        }
+
+        currentAnimator?.let {
+            it.cancel()
+            child.clearAnimation()
+        }
+
+        currentState = STATE_SCROLLED_UP
+        animateChildTo(
+            child,
+            0,
+            ENTER_ANIMATION_DURATION.toLong(),
+            AnimationUtils.LINEAR_OUT_SLOW_IN_INTERPOLATOR
+        )
+    }
+
+    /**
+     * Perform an animation that will slide the child from it's current position to be totally off the
+     * screen.
+     */
+    override fun slideUp(child: V) {
+        if (currentState == STATE_SCROLLED_DOWN) {
+            return
+        }
+
+        currentAnimator?.let {
+            it.cancel()
+            child.clearAnimation()
+        }
+
+        currentState = STATE_SCROLLED_DOWN
+        animateChildTo(
+            child,
+            -(height + additionalHiddenOffsetY),
+            EXIT_ANIMATION_DURATION.toLong(),
+            AnimationUtils.FAST_OUT_LINEAR_IN_INTERPOLATOR
+        )
+    }
+
+    private fun animateChildTo(
+        child: V,
+        targetY: Int,
+        duration: Long,
+        interpolator: TimeInterpolator
+    ) = child
+        .animate()
+        .translationY(targetY.toFloat())
+        .setInterpolator(interpolator)
+        .setDuration(duration)
+        .withEndAction { currentAnimator = null }
+        .let { currentAnimator = it }
+}