HW Samoykin

app/build.gradle

@@ -36,6 +36,7 @@ dependencies {
 
     implementation 'androidx.core:core-ktx:1.7.0'
     implementation 'androidx.appcompat:appcompat:1.5.1'
+    implementation 'androidx.recyclerview:recyclerview:1.3.2'
     implementation 'com.google.android.material:material:1.7.0'
     implementation 'androidx.constraintlayout:constraintlayout:2.1.4'
     testImplementation 'junit:junit:4.13.2'

app/src/main/java/otus/gpb/recyclerview/Chat.kt

@@ -0,0 +1,25 @@
+package otus.gpb.recyclerview
+
+import androidx.annotation.ColorInt
+import androidx.annotation.DrawableRes
+
+data class Chat(
+    val id: Long,
+    val title: String,
+    val message: String,
+    val time: String,
+    val avatarLetters: String,
+    @ColorInt val avatarColor: Int,
+    @DrawableRes val avatarResId: Int? = null,
+    val unreadCount: Int = 0,
+    val isVerified: Boolean = false,
+    val isMuted: Boolean = false,
+    val isPinned: Boolean = false,
+    val isOnline: Boolean = false,
+    val hasMention: Boolean = false,
+    val deliveryState: DeliveryState = DeliveryState.NONE,
+    val messageState: MessageState = MessageState.REGULAR,
+) {
+    enum class DeliveryState { NONE, SENT, READ }
+    enum class MessageState { REGULAR, DRAFT, TYPING }
+}

app/src/main/java/otus/gpb/recyclerview/ChatAdapter.kt

@@ -0,0 +1,96 @@
+package otus.gpb.recyclerview
+
+import android.graphics.drawable.GradientDrawable
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import android.widget.ImageView
+import android.widget.TextView
+import androidx.core.content.ContextCompat
+import androidx.core.view.isVisible
+import androidx.recyclerview.widget.DiffUtil
+import androidx.recyclerview.widget.ListAdapter
+import androidx.recyclerview.widget.RecyclerView
+
+class ChatAdapter : ListAdapter<Chat, ChatAdapter.ChatViewHolder>(DiffCallback) {
+
+    init {
+        setHasStableIds(true)
+        stateRestorationPolicy = StateRestorationPolicy.PREVENT_WHEN_EMPTY
+    }
+
+    override fun getItemId(position: Int): Long = getItem(position).id
+
+    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ChatViewHolder {
+        val view = LayoutInflater.from(parent.context).inflate(R.layout.item_chat, parent, false)
+        return ChatViewHolder(view)
+    }
+
+    override fun onBindViewHolder(holder: ChatViewHolder, position: Int) {
+        holder.bind(getItem(position))
+    }
+
+    class ChatViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
+        private val avatarImage = itemView.findViewById<ImageView>(R.id.avatarImage)
+        private val avatarInitials = itemView.findViewById<TextView>(R.id.avatarInitials)
+        private val online = itemView.findViewById<View>(R.id.onlineIndicator)
+        private val title = itemView.findViewById<TextView>(R.id.chatTitle)
+        private val verified = itemView.findViewById<ImageView>(R.id.verifiedBadge)
+        private val muted = itemView.findViewById<ImageView>(R.id.mutedBadge)
+        private val message = itemView.findViewById<TextView>(R.id.lastMessage)
+        private val typingDots = itemView.findViewById<ImageView>(R.id.typingDots)
+        private val time = itemView.findViewById<TextView>(R.id.chatTime)
+        private val delivery = itemView.findViewById<View>(R.id.deliveryState)
+        private val firstCheck = itemView.findViewById<ImageView>(R.id.firstCheck)
+        private val unread = itemView.findViewById<TextView>(R.id.unreadBadge)
+        private val pinned = itemView.findViewById<ImageView>(R.id.pinnedBadge)
+        private val mention = itemView.findViewById<ImageView>(R.id.mentionBadge)
+        private val trailingStatus = itemView.findViewById<View>(R.id.trailingStatus)
+
+        fun bind(chat: Chat) {
+            avatarImage.isVisible = chat.avatarResId != null
+            avatarInitials.isVisible = chat.avatarResId == null
+            chat.avatarResId?.let(avatarImage::setImageResource)
+            avatarInitials.text = chat.avatarLetters
+            avatarInitials.background = GradientDrawable().apply {
+                shape = GradientDrawable.OVAL
+                setColor(chat.avatarColor)
+            }
+
+            online.isVisible = chat.isOnline
+            title.text = chat.title
+            verified.isVisible = chat.isVerified
+            muted.isVisible = chat.isMuted
+            time.text = chat.time
+
+            val isTyping = chat.messageState == Chat.MessageState.TYPING
+            typingDots.isVisible = isTyping
+            message.text = chat.message
+            message.setTextColor(
+                ContextCompat.getColor(
+                    itemView.context,
+                    when (chat.messageState) {
+                        Chat.MessageState.TYPING -> R.color.telegram_typing
+                        Chat.MessageState.DRAFT -> R.color.telegram_red
+                        Chat.MessageState.REGULAR -> R.color.text_secondary
+                    },
+                ),
+            )
+
+            delivery.isVisible = chat.deliveryState != Chat.DeliveryState.NONE
+            firstCheck.isVisible = chat.deliveryState == Chat.DeliveryState.READ
+
+            val hasUnread = chat.unreadCount > 0 && !chat.hasMention
+            unread.isVisible = hasUnread
+            unread.text = itemView.resources.getString(R.string.unread_count, chat.unreadCount)
+            mention.isVisible = chat.hasMention
+            pinned.isVisible = chat.isPinned && !hasUnread && !chat.hasMention
+            trailingStatus.isVisible = hasUnread || chat.hasMention || pinned.isVisible
+        }
+    }
+
+    private object DiffCallback : DiffUtil.ItemCallback<Chat>() {
+        override fun areItemsTheSame(oldItem: Chat, newItem: Chat) = oldItem.id == newItem.id
+        override fun areContentsTheSame(oldItem: Chat, newItem: Chat) = oldItem == newItem
+    }
+}

app/src/main/java/otus/gpb/recyclerview/ChatDividerDecoration.kt

@@ -0,0 +1,25 @@
+package otus.gpb.recyclerview
+
+import android.graphics.Canvas
+import android.graphics.Paint
+import androidx.recyclerview.widget.RecyclerView
+
+class ChatDividerDecoration(
+    dividerColor: Int,
+    private val startInset: Int,
+    private val height: Int,
+) : RecyclerView.ItemDecoration() {
+    private val paint = Paint(Paint.ANTI_ALIAS_FLAG).apply { color = dividerColor }
+
+    override fun onDrawOver(canvas: Canvas, parent: RecyclerView, state: RecyclerView.State) {
+        val end = parent.width - parent.paddingRight
+        for (index in 0 until parent.childCount) {
+            val child = parent.getChildAt(index)
+            val adapterPosition = parent.getChildAdapterPosition(child)
+            if (adapterPosition == RecyclerView.NO_POSITION || adapterPosition >= state.itemCount - 1) continue
+            val decoratedBottom = parent.layoutManager?.getDecoratedBottom(child) ?: child.bottom
+            val top = decoratedBottom + child.translationY.toInt()
+            canvas.drawRect(startInset.toFloat(), top.toFloat(), end.toFloat(), (top + height).toFloat(), paint)
+        }
+    }
+}

app/src/main/java/otus/gpb/recyclerview/ChatFactory.kt

@@ -0,0 +1,68 @@
+package otus.gpb.recyclerview
+
+import androidx.annotation.ColorInt
+import androidx.annotation.DrawableRes
+import java.util.Locale
+
+object ChatFactory {
+    private data class Sample(
+        val title: String,
+        val message: String,
+        val initials: String,
+        @ColorInt val color: Int,
+        @DrawableRes val avatarResId: Int? = null,
+        val verified: Boolean = false,
+        val muted: Boolean = false,
+        val pinned: Boolean = false,
+        val online: Boolean = false,
+        val mention: Boolean = false,
+        val unread: Int = 0,
+        val delivery: Chat.DeliveryState = Chat.DeliveryState.NONE,
+        val state: Chat.MessageState = Chat.MessageState.REGULAR,
+    )
+
+    private val samples = listOf(
+        Sample("Dima Murantsev", "Всегда пожалуйста :)", "DM", 0xFFD89B68.toInt(), R.drawable.avatar_dima, verified = true, pinned = true, delivery = Chat.DeliveryState.READ),
+        Sample("Оффтопка", "А в вашем инфоне это есть?", "ОФ", 0xFF78A9C4.toInt(), R.drawable.avatar_offtopic, muted = true, pinned = true, online = true),
+        Sample("Catbird", "печатает", "CB", 0xFF7C6AB0.toInt(), R.drawable.avatar_catbird, pinned = true, state = Chat.MessageState.TYPING),
+        Sample("just design", "Вы: я хочу пить", "JD", 0xFF9193E8.toInt(), R.drawable.avatar_just_design, muted = true, mention = true, delivery = Chat.DeliveryState.READ),
+        Sample("R4INB0W", "du biest mein sonnchein", "R4", 0xFF454D68.toInt(), R.drawable.avatar_r4inbow),
+        Sample("Да. Нет.", "Красиво", "ДН", 0xFF3994C6.toInt(), R.drawable.avatar_yes_no, verified = true, unread = 50, delivery = Chat.DeliveryState.SENT),
+        Sample("SMDDN", "Сними с меня скам!", "SM", 0xFF5B7EA6.toInt(), R.drawable.avatar_smddn),
+        Sample("Android Developers", "RecyclerView умеет больше, чем кажется", "AD", 0xFF3DDC84.toInt(), verified = true, unread = 3),
+        Sample("Учебная группа", "Задание сдано на проверку", "УГ", 0xFFF2A65A.toInt(), muted = true, unread = 12),
+        Sample("Saved Messages", "Макет Telegram", "SM", 0xFF4AA3DF.toInt(), delivery = Chat.DeliveryState.READ),
+    )
+
+    fun createPage(page: Int, pageSize: Int = 10): List<Chat> = List(pageSize) { index ->
+        val absoluteIndex = page * pageSize + index
+        val sample = samples[absoluteIndex % samples.size]
+        val cycle = absoluteIndex / samples.size
+        sample.toChat(
+            id = absoluteIndex.toLong(),
+            suffix = if (cycle == 0) "" else " ${cycle + 1}",
+            minutesAgo = absoluteIndex % 60,
+        )
+    }
+
+    private fun Sample.toChat(id: Long, suffix: String, minutesAgo: Int): Chat {
+        val totalMinutes = 11 * 60 + 38 + minutesAgo
+        return Chat(
+            id = id,
+            title = title + suffix,
+            message = message,
+            time = String.format(Locale.US, "%02d:%02d", totalMinutes / 60, totalMinutes % 60),
+            avatarLetters = initials,
+            avatarColor = color,
+            avatarResId = avatarResId,
+            unreadCount = unread,
+            isVerified = verified,
+            isMuted = muted,
+            isPinned = pinned,
+            isOnline = online,
+            hasMention = mention,
+            deliveryState = delivery,
+            messageState = state,
+        )
+    }
+}

app/src/main/java/otus/gpb/recyclerview/ChatSwipeCallback.kt

@@ -0,0 +1,77 @@
+package otus.gpb.recyclerview
+
+import android.content.Context
+import android.graphics.Canvas
+import android.graphics.Color
+import android.graphics.Paint
+import android.graphics.drawable.Drawable
+import androidx.core.content.ContextCompat
+import androidx.recyclerview.widget.ItemTouchHelper
+import androidx.recyclerview.widget.RecyclerView
+
+class ChatSwipeCallback(
+    context: Context,
+    private val onDismissed: (chatId: Long) -> Unit,
+) : ItemTouchHelper.SimpleCallback(0, ItemTouchHelper.LEFT) {
+    private val density = context.resources.displayMetrics.density
+    private val archiveIcon: Drawable = requireNotNull(
+        ContextCompat.getDrawable(context, R.drawable.ic_archive),
+    ).mutate()
+    private val archiveLabel = context.getString(R.string.archive)
+    private val backgroundPaint = Paint(Paint.ANTI_ALIAS_FLAG).apply {
+        color = ContextCompat.getColor(context, R.color.swipe_archive)
+    }
+    private val textPaint = Paint(Paint.ANTI_ALIAS_FLAG).apply {
+        color = Color.WHITE
+        textSize = context.resources.getDimension(R.dimen.swipe_label_size)
+        textAlign = Paint.Align.CENTER
+        typeface = android.graphics.Typeface.create("sans-serif-medium", android.graphics.Typeface.NORMAL)
+    }
+
+    override fun onMove(
+        recyclerView: RecyclerView,
+        viewHolder: RecyclerView.ViewHolder,
+        target: RecyclerView.ViewHolder,
+    ) = false
+
+    override fun onSwiped(viewHolder: RecyclerView.ViewHolder, direction: Int) {
+        if (viewHolder.itemId != RecyclerView.NO_ID) onDismissed(viewHolder.itemId)
+    }
+
+    override fun getSwipeThreshold(viewHolder: RecyclerView.ViewHolder) = 0.7f
+
+    override fun onChildDraw(
+        canvas: Canvas,
+        recyclerView: RecyclerView,
+        viewHolder: RecyclerView.ViewHolder,
+        dX: Float,
+        dY: Float,
+        actionState: Int,
+        isCurrentlyActive: Boolean,
+    ) {
+        val item = viewHolder.itemView
+        if (dX < 0f) {
+            canvas.drawRect(
+                item.right + dX,
+                item.top.toFloat(),
+                item.right.toFloat(),
+                item.bottom.toFloat(),
+                backgroundPaint,
+            )
+
+            val centerX = item.right - 41f * density
+            val centerY = (item.top + item.bottom) / 2f
+            val iconSize = (30f * density).toInt()
+            val iconCenterY = centerY - 9f * density
+            archiveIcon.setBounds(
+                (centerX - iconSize / 2f).toInt(),
+                (iconCenterY - iconSize / 2f).toInt(),
+                (centerX + iconSize / 2f).toInt(),
+                (iconCenterY + iconSize / 2f).toInt(),
+            )
+            archiveIcon.draw(canvas)
+            canvas.drawText(archiveLabel, centerX, centerY + 28f * density, textPaint)
+        }
+        super.onChildDraw(canvas, recyclerView, viewHolder, dX, dY, actionState, isCurrentlyActive)
+    }
+}