Improve image viewer (#1843)

This commit does 3 things:
1. Replaces PhotoView (which is abandonware) with modern TouchImageView
2. Fixes an issue with panning images. Gesture was not intercepted
properly and pager was taking control instead of image being moved.
3. Adds feedback to dismissing of images with vertical gesture.
This commit is contained in:
Ivan Kupalov 2020-06-22 21:26:37 +02:00 committed by GitHub
parent 8245e00a29
commit 58a1046348
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4 changed files with 72 additions and 38 deletions

View File

@ -159,7 +159,7 @@ dependencies {
implementation "com.github.connyduck:sparkbutton:4.0.0"
implementation "com.github.chrisbanes:PhotoView:2.3.0"
implementation 'com.github.MikeOrtiz:TouchImageView:3.0.1'
implementation "com.mikepenz:materialdrawer:$materialdrawerVersion"
implementation "com.mikepenz:materialdrawer-iconics:$materialdrawerVersion"

View File

@ -33,9 +33,9 @@ import at.connyduck.sparkbutton.helpers.Utils
import com.bumptech.glide.Glide
import com.bumptech.glide.request.target.CustomTarget
import com.bumptech.glide.request.transition.Transition
import com.github.chrisbanes.photoview.PhotoView
import com.keylesspalace.tusky.R
import com.keylesspalace.tusky.util.withLifecycleContext
import com.ortiz.touchview.TouchImageView
// https://github.com/tootsuite/mastodon/blob/1656663/app/models/media_attachment.rb#L94
private const val MEDIA_DESCRIPTION_CHARACTER_LIMIT = 420
@ -50,9 +50,8 @@ fun <T> T.makeCaptionDialog(existingDescription: String?,
dialogLayout.setPadding(padding, padding, padding, padding)
dialogLayout.orientation = LinearLayout.VERTICAL
val imageView = PhotoView(this).apply {
// If it seems a lot, try opening an image of A4 format or similar
maximumScale = 6.0f
val imageView = TouchImageView(this).apply {
maxZoom = 6f
}
val displayMetrics = DisplayMetrics()

View File

@ -21,9 +21,7 @@ import android.annotation.SuppressLint
import android.content.Context
import android.graphics.drawable.Drawable
import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.view.*
import android.widget.ImageView
import android.widget.TextView
import com.bumptech.glide.Glide
@ -31,7 +29,6 @@ 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.github.chrisbanes.photoview.PhotoViewAttacher
import com.keylesspalace.tusky.R
import com.keylesspalace.tusky.entity.Attachment
import com.keylesspalace.tusky.util.hide
@ -48,11 +45,11 @@ class ViewImageFragment : ViewMediaFragment() {
fun onPhotoTap()
}
private lateinit var attacher: PhotoViewAttacher
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
@ -67,23 +64,6 @@ class ViewImageFragment : ViewMediaFragment() {
override fun setupMediaView(url: String, previewUrl: String?) {
descriptionView = mediaDescription
photoView.transitionName = url
attacher = PhotoViewAttacher(photoView).apply {
// Clicking outside the photo closes the viewer.
setOnOutsidePhotoTapListener { photoActionsListener.onDismiss() }
setOnClickListener { onMediaTap() }
/* A vertical swipe motion also closes the viewer. This is especially useful when the photo
* mostly fills the screen so clicking outside is difficult. */
setOnSingleFlingListener { _, _, velocityX, velocityY ->
var result = false
if (abs(velocityY) > abs(velocityX)) {
photoActionsListener.onDismiss()
result = true
}
result
}
}
startedTransition = false
loadImageFromNetwork(url, previewUrl, photoView)
}
@ -94,9 +74,65 @@ class ViewImageFragment : ViewMediaFragment() {
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)
@ -116,6 +152,14 @@ class ViewImageFragment : ViewMediaFragment() {
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()
}
@ -155,7 +199,6 @@ class ViewImageFragment : ViewMediaFragment() {
.load(previewUrl)
.dontAnimate()
.onlyRetrieveFromCache(true)
.centerInside()
.addListener(ImageRequestListener(true, isThumnailRequest = true)))
else it
}
@ -164,7 +207,6 @@ class ViewImageFragment : ViewMediaFragment() {
.centerInside()
.addListener(ImageRequestListener(false, isThumnailRequest = false))
)
.centerInside()
.addListener(ImageRequestListener(true, isThumnailRequest = false))
.into(photoView)
}
@ -225,13 +267,7 @@ class ViewImageFragment : ViewMediaFragment() {
// another branch. take() will unsubscribe after we have it to not leak menmory
transition
.take(1)
.subscribe {
target.onResourceReady(resource, null)
// It's needed. Don't ask why, I don't know, setImageDrawable() should
// do it by itself but somehow it doesn't work automatically.
// Just do it. If you don't, image will jump around when touched.
attacher.update()
}
.subscribe { target.onResourceReady(resource, null) }
}
return true
}

View File

@ -4,11 +4,10 @@
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="center"
android:clickable="true"
android:focusable="true">
<com.github.chrisbanes.photoview.PhotoView
<com.ortiz.touchview.TouchImageView
android:id="@+id/photoView"
android:layout_width="match_parent"
android:layout_height="match_parent" />