Yuito-app-android/app/src/main/java/com/keylesspalace/tusky/fragment/ViewImageFragment.kt

280 lines
12 KiB
Kotlin

/* Copyright 2017 Andrew Dawson
*
* 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>. */
package com.keylesspalace.tusky.fragment
import android.animation.Animator
import android.animation.AnimatorListenerAdapter
import android.annotation.SuppressLint
import android.content.Context
import android.graphics.drawable.Drawable
import android.os.Bundle
import android.view.*
import android.widget.ImageView
import android.widget.TextView
import com.bumptech.glide.Glide
import com.bumptech.glide.load.DataSource
import com.bumptech.glide.load.engine.GlideException
import com.bumptech.glide.request.RequestListener
import com.bumptech.glide.request.target.Target
import com.keylesspalace.tusky.R
import com.keylesspalace.tusky.entity.Attachment
import com.keylesspalace.tusky.util.hide
import com.keylesspalace.tusky.util.visible
import io.reactivex.subjects.BehaviorSubject
import kotlinx.android.synthetic.main.activity_view_media.*
import kotlinx.android.synthetic.main.fragment_view_image.*
import kotlin.math.abs
class ViewImageFragment : ViewMediaFragment() {
interface PhotoActionsListener {
fun onBringUp()
fun onDismiss()
fun onPhotoTap()
}
private lateinit var photoActionsListener: PhotoActionsListener
private lateinit var toolbar: View
private var transition = BehaviorSubject.create<Unit>()
private var shouldStartTransition = false
// Volatile: Image requests happen on background thread and we want to see updates to it
// immediately on another thread. Atomic is an overkill for such thing.
@Volatile
private var startedTransition = false
override lateinit var descriptionView: TextView
override fun onAttach(context: Context) {
super.onAttach(context)
photoActionsListener = context as PhotoActionsListener
}
override fun setupMediaView(url: String, previewUrl: String?) {
descriptionView = mediaDescription
photoView.transitionName = url
startedTransition = false
loadImageFromNetwork(url, previewUrl, photoView)
}
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View {
toolbar = requireActivity().toolbar
this.transition = BehaviorSubject.create()
return inflater.inflate(R.layout.fragment_view_image, container, false)
}
@SuppressLint("ClickableViewAccessibility")
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
val gestureDetector = GestureDetector(requireContext(), object : GestureDetector.SimpleOnGestureListener() {
override fun onSingleTapConfirmed(e: MotionEvent?): Boolean {
onMediaTap()
return true
}
})
var lastY = 0f
photoView.setOnTouchListener { _, event ->
// This part is for scaling/translating on vertical move.
// We use raw coordinates to get the correct ones during scaling
var result = true
gestureDetector.onTouchEvent(event)
if (event.action == MotionEvent.ACTION_DOWN) {
lastY = event.rawY
} else if (!photoView.isZoomed && event.action == MotionEvent.ACTION_MOVE) {
val diff = event.rawY - lastY
// This code is to prevent transformations during page scrolling
// If we are already translating or we reached the threshold, then transform.
if (photoView.translationY != 0f || abs(diff) > 40) {
photoView.translationY += (diff)
val scale = (-abs(photoView.translationY) / 720 + 1).coerceAtLeast(0.5f)
photoView.scaleY = scale
photoView.scaleX = scale
lastY = event.rawY
}
return@setOnTouchListener true
} else if (event.action == MotionEvent.ACTION_UP || event.action == MotionEvent.ACTION_CANCEL) {
onGestureEnd()
} else if (event.pointerCount >= 2 || photoView.canScrollHorizontally(1) && photoView.canScrollHorizontally(-1)) {
// Starting from here is adapted code from TouchImageView to play nice with pager.
// Can scroll horizontally checks if there's still a part of the image.
// That can be scrolled until you reach the edge multi-touch event.
val parent = view.parent
result = when (event.action) {
MotionEvent.ACTION_DOWN, MotionEvent.ACTION_MOVE -> {
// Disallow RecyclerView to intercept touch events.
parent.requestDisallowInterceptTouchEvent(true)
// Disable touch on view
false
}
MotionEvent.ACTION_UP -> {
// Allow RecyclerView to intercept touch events.
parent.requestDisallowInterceptTouchEvent(false)
true
}
else -> true
}
}
result
}
val arguments = this.requireArguments()
val attachment = arguments.getParcelable<Attachment>(ARG_ATTACHMENT)
this.shouldStartTransition = arguments.getBoolean(ARG_START_POSTPONED_TRANSITION)
val url: String?
var description: String? = null
if (attachment != null) {
url = attachment.url
description = attachment.description
} else {
url = arguments.getString(ARG_AVATAR_URL)
if (url == null) {
throw IllegalArgumentException("attachment or avatar url has to be set")
}
}
finalizeViewSetup(url, attachment?.previewUrl, description)
}
private fun onGestureEnd() {
if (abs(photoView.translationY) > 180) {
photoActionsListener.onDismiss()
} else {
photoView.animate().translationY(0f).scaleX(1f).scaleY(1f).start()
}
}
private fun onMediaTap() {
photoActionsListener.onPhotoTap()
}
override fun onToolbarVisibilityChange(visible: Boolean) {
if (photoView == null || !userVisibleHint) {
return
}
isDescriptionVisible = showingDescription && visible
val alpha = if (isDescriptionVisible) 1.0f else 0.0f
descriptionView.animate().alpha(alpha)
.setListener(object : AnimatorListenerAdapter() {
override fun onAnimationEnd(animation: Animator) {
descriptionView.visible(isDescriptionVisible)
animation.removeListener(this)
}
})
.start()
}
override fun onDestroyView() {
Glide.with(this).clear(photoView)
transition.onComplete()
super.onDestroyView()
}
private fun loadImageFromNetwork(url: String, previewUrl: String?, photoView: ImageView) {
val glide = Glide.with(this)
// Request image from the any cache
glide
.load(url)
.dontAnimate()
.onlyRetrieveFromCache(true)
.let {
if (previewUrl != null)
it.thumbnail(glide
.load(previewUrl)
.dontAnimate()
.onlyRetrieveFromCache(true)
.addListener(ImageRequestListener(true, isThumnailRequest = true)))
else it
}
//Request image from the network on fail load image from cache
.error(glide.load(url)
.centerInside()
.addListener(ImageRequestListener(false, isThumnailRequest = false))
)
.addListener(ImageRequestListener(true, isThumnailRequest = false))
.into(photoView)
}
/**
* We start transition as soon as we think reasonable but we must take care about couple of
* things>
* - Do not change image in the middle of transition. It messes up the view.
* - Do not transition for the views which don't require it. Starting transition from
* multiple fragments does weird things
* - Do not wait to transition until the image loads from network
*
* Preview, cached image, network image, x - failed, o - succeeded
* P C N - start transition after...
* x x x - the cache fails
* x x o - the cache fails
* x o o - the cache succeeds
* o x o - the preview succeeds. Do not start on cache.
* o o o - the preview succeeds. Do not start on cache.
*
* So start transition after the first success or after anything with the cache
*
* @param isCacheRequest - is this listener for request image from cache or from the network
*/
private inner class ImageRequestListener(
private val isCacheRequest: Boolean,
private val isThumnailRequest: Boolean) : RequestListener<Drawable> {
override fun onLoadFailed(e: GlideException?, model: Any, target: Target<Drawable>,
isFirstResource: Boolean): Boolean {
// If cache for full image failed complete transition
if (isCacheRequest && !isThumnailRequest && shouldStartTransition
&& !startedTransition) {
photoActionsListener.onBringUp()
}
// Hide progress bar only on fail request from internet
if (!isCacheRequest) progressBar?.hide()
// We don't want to overwrite preview with null when main image fails to load
return !isCacheRequest
}
@SuppressLint("CheckResult")
override fun onResourceReady(resource: Drawable, model: Any, target: Target<Drawable>,
dataSource: DataSource, isFirstResource: Boolean): Boolean {
progressBar?.hide() // Always hide the progress bar on success
if (!startedTransition || !shouldStartTransition) {
// Set this right away so that we don't have to concurrent post() requests
startedTransition = true
// post() because load() replaces image with null. Sometimes after we set
// the thumbnail.
photoView.post {
target.onResourceReady(resource, null)
if (shouldStartTransition) photoActionsListener.onBringUp()
}
} else {
// This wait for transition. If there's no transition then we should hit
// another branch. take() will unsubscribe after we have it to not leak menmory
transition
.take(1)
.subscribe { target.onResourceReady(resource, null) }
}
return true
}
}
override fun onTransitionEnd() {
this.transition.onNext(Unit)
}
}