Yuito-app-android/app/src/main/java/com/keylesspalace/tusky/util/TouchDelegateHelper.kt

65 lines
2.2 KiB
Kotlin

/* Copyright 2022 Tusky contributors
* This file is a part of Tusky.
*
* This program is free software; you can redistribute it and/or modify it under the terms of the
* GNU General Public License as published by the Free Software Foundation; either version 3 of the
* License, or (at your option) any later version.
*
* Tusky is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
* the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
* Public License for more details.
*
* You should have received a copy of the GNU General Public License along with Tusky; if not,
* see <http://www.gnu.org/licenses>. */
@file:JvmName("TouchDelegateHelper")
package com.keylesspalace.tusky.util
import android.graphics.Rect
import android.view.MotionEvent
import android.view.TouchDelegate
import android.view.View
import android.view.ViewGroup
/**
* Expands the touch area of the give row of views to fill the space in-between them, using a
* [TouchDelegate].
*/
fun ViewGroup.expandTouchSizeToFillRow(children: List<View>) {
addOnLayoutChangeListener { _, _, _, _, _, _, _, _, _ ->
touchDelegate = CompositeTouchDelegate(
this,
children.mapIndexed { i, view ->
val rect = Rect()
view.getHitRect(rect)
val left = children.getOrNull(i - 1)
if (left != null) {
// extend half-way to previous view
rect.left -= (view.left - left.right) / 2
}
val right = children.getOrNull(i + 1)
if (right != null) {
// extend half-way to next view
rect.right += (right.left - view.right) / 2
}
TouchDelegate(rect, view)
}
)
}
}
private class CompositeTouchDelegate(view: View, private val delegates: List<TouchDelegate>) :
TouchDelegate(Rect(), view) {
override fun onTouchEvent(event: MotionEvent): Boolean {
val x = event.x
val y = event.y
return delegates.fold(false) { res, delegate ->
event.setLocation(x, y)
delegate.onTouchEvent(event) || res
}
}
}