android: Create generic single selection list adapter
This commit is contained in:
parent
9130366a58
commit
b17db2b462
|
@ -0,0 +1,105 @@
|
|||
// SPDX-FileCopyrightText: 2024 yuzu Emulator Project
|
||||
// SPDX-License-Identifier: GPL-2.0-or-later
|
||||
|
||||
package org.yuzu.yuzu_emu.adapters
|
||||
|
||||
import org.yuzu.yuzu_emu.model.SelectableItem
|
||||
import org.yuzu.yuzu_emu.viewholder.AbstractViewHolder
|
||||
|
||||
/**
|
||||
* Generic list class meant to take care of single selection UI updates
|
||||
* @param currentList The list to show initially
|
||||
* @param defaultSelection The default selection to use if no list items are selected by
|
||||
* [SelectableItem.selected] or if the currently selected item is removed from the list
|
||||
*/
|
||||
abstract class AbstractSingleSelectionList<
|
||||
Model : SelectableItem,
|
||||
Holder : AbstractViewHolder<Model>
|
||||
>(
|
||||
final override var currentList: List<Model>,
|
||||
private val defaultSelection: DefaultSelection = DefaultSelection.Start
|
||||
) : AbstractListAdapter<Model, Holder>(currentList) {
|
||||
var selectedItem = getDefaultSelection()
|
||||
|
||||
init {
|
||||
findSelectedItem()
|
||||
}
|
||||
|
||||
/**
|
||||
* Changes the selection state of the [SelectableItem] that was selected and the previously selected
|
||||
* item and notifies the underlying adapter of the change for those items. Invokes [callback] last.
|
||||
* Does nothing if [position] is the same as the currently selected item.
|
||||
* @param position Index of the item that was selected
|
||||
* @param callback Lambda that's called at the end of the list changes and has the selected list
|
||||
* position passed in as a parameter
|
||||
*/
|
||||
fun selectItem(position: Int, callback: ((position: Int) -> Unit)? = null) {
|
||||
if (position == selectedItem) {
|
||||
return
|
||||
}
|
||||
|
||||
val previouslySelectedItem = selectedItem
|
||||
selectedItem = position
|
||||
if (currentList.indices.contains(selectedItem)) {
|
||||
currentList[selectedItem].onSelectionStateChanged(true)
|
||||
}
|
||||
if (currentList.indices.contains(previouslySelectedItem)) {
|
||||
currentList[previouslySelectedItem].onSelectionStateChanged(false)
|
||||
}
|
||||
onItemChanged(previouslySelectedItem)
|
||||
onItemChanged(selectedItem)
|
||||
callback?.invoke(position)
|
||||
}
|
||||
|
||||
/**
|
||||
* Removes a given item from the list and notifies the underlying adapter of the change. If the
|
||||
* currently selected item was the item that was removed, the item at the position provided
|
||||
* by [defaultSelection] will be made the new selection. Invokes [callback] last.
|
||||
* @param position Index of the item that was removed
|
||||
* @param callback Lambda that's called at the end of the list changes and has the removed and
|
||||
* selected list positions passed in as parameters
|
||||
*/
|
||||
fun removeSelectableItem(
|
||||
position: Int,
|
||||
callback: ((removedPosition: Int, selectedPosition: Int) -> Unit)?
|
||||
) {
|
||||
removeItem(position)
|
||||
if (position == selectedItem) {
|
||||
selectedItem = getDefaultSelection()
|
||||
currentList[selectedItem].onSelectionStateChanged(true)
|
||||
onItemChanged(selectedItem)
|
||||
} else if (position < selectedItem) {
|
||||
selectedItem--
|
||||
}
|
||||
callback?.invoke(position, selectedItem)
|
||||
}
|
||||
|
||||
override fun addItem(item: Model, position: Int, callback: ((Int) -> Unit)?) {
|
||||
super.addItem(item, position, callback)
|
||||
if (position <= selectedItem && position != -1) {
|
||||
selectedItem++
|
||||
}
|
||||
}
|
||||
|
||||
override fun replaceList(newList: List<Model>) {
|
||||
super.replaceList(newList)
|
||||
findSelectedItem()
|
||||
}
|
||||
|
||||
private fun findSelectedItem() {
|
||||
for (i in currentList.indices) {
|
||||
if (currentList[i].selected) {
|
||||
selectedItem = i
|
||||
break
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
private fun getDefaultSelection(): Int =
|
||||
when (defaultSelection) {
|
||||
DefaultSelection.Start -> currentList.indices.first
|
||||
DefaultSelection.End -> currentList.indices.last
|
||||
}
|
||||
|
||||
enum class DefaultSelection { Start, End }
|
||||
}
|
|
@ -0,0 +1,9 @@
|
|||
// SPDX-FileCopyrightText: 2024 yuzu Emulator Project
|
||||
// SPDX-License-Identifier: GPL-2.0-or-later
|
||||
|
||||
package org.yuzu.yuzu_emu.model
|
||||
|
||||
interface SelectableItem {
|
||||
var selected: Boolean
|
||||
fun onSelectionStateChanged(selected: Boolean)
|
||||
}
|
Reference in New Issue