Fix image zoom / pan / scroll / swipe (#3894)

Migrate to touchimageview from photoview, and adjust the touch logic to correctly handle single finger drag, two finger pinch/stretch, flings, taps, and swipes.

As before, the features are:

- Single tap, show/hide controls and media description
- Double tap, zoom in/out
- Single finger drag up/down, scale/translate image, dismiss if scrolled too far
- Single finger drag left/right
  - When not zoomed, swipe to next image if multiple images present
- When zoomed, scroll to edge of image, then to next image if multiple images present
- Two finger pinch/zoom, zoom in/out on the image

Behaviour differences to previous code

1. Bug fix: The image can't get "stuck" when zoomed, and impossible to scroll
2. Bug fix: Pinching is not mis-interpreted as a fling, closing the image
3. Bug fix: The zoom state of images is not lost or misinterpreted when the user swipes through multiple images
4. Bug fix: Double-tap zooms all the way, instead of stopping
5. Tapping outside the image does not dismiss it, controls and description show/hide

Fixes https://github.com/tuskyapp/Tusky/issues/3562, https://github.com/tuskyapp/Tusky/issues/2297
This commit is contained in:
Nik Clayton 2023-07-31 12:44:01 +02:00 committed by GitHub
parent 30be3ce1f0
commit 79ee2dc32c
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6 changed files with 145 additions and 87 deletions

View File

@ -158,7 +158,7 @@ dependencies {
implementation libs.sparkbutton
implementation libs.photoview
implementation libs.touchimageview
implementation libs.bundles.material.drawer
implementation libs.material.typeface
@ -186,3 +186,20 @@ dependencies {
androidTestImplementation libs.androidx.room.testing
androidTestImplementation libs.androidx.test.junit
}
// Work around warnings of:
// WARNING: Illegal reflective access by org.jetbrains.kotlin.kapt3.util.ModuleManipulationUtilsKt (file:/C:/Users/Andi/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-annotation-processing-gradle/1.8.22/28dab7e0ee9ce62c03bf97de3543c911dc653700/kotlin-annotation-processing-gradle-1.8.22.jar) to constructor com.sun.tools.javac.util.Context()
// See https://youtrack.jetbrains.com/issue/KT-30589/Kapt-An-illegal-reflective-access-operation-has-occurred
tasks.withType(org.jetbrains.kotlin.gradle.internal.KaptWithoutKotlincTask) {
kaptProcessJvmArgs.addAll([
"--add-opens", "jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED",
"--add-opens", "jdk.compiler/com.sun.tools.javac.file=ALL-UNNAMED",
"--add-opens", "jdk.compiler/com.sun.tools.javac.main=ALL-UNNAMED",
"--add-opens", "jdk.compiler/com.sun.tools.javac.jvm=ALL-UNNAMED",
"--add-opens", "jdk.compiler/com.sun.tools.javac.processing=ALL-UNNAMED",
"--add-opens", "jdk.compiler/com.sun.tools.javac.comp=ALL-UNNAMED",
"--add-opens", "jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED",
"--add-opens", "jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED",
"--add-opens", "jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED",
"--add-opens", "jdk.compiler/com.sun.tools.javac.code=ALL-UNNAMED"])
}

View File

@ -51,7 +51,7 @@ class CaptionDialog : DialogFragment() {
input = binding.imageDescriptionText
val imageView = binding.imageDescriptionView
imageView.maximumScale = 6f
imageView.maxZoom = 6f
input.hint = resources.getQuantityString(
R.plurals.hint_describe_for_visually_impaired,

View File

@ -19,25 +19,31 @@ import android.animation.Animator
import android.animation.AnimatorListenerAdapter
import android.annotation.SuppressLint
import android.content.Context
import android.graphics.PointF
import android.graphics.drawable.Drawable
import android.os.Bundle
import android.view.GestureDetector
import android.view.LayoutInflater
import android.view.MotionEvent
import android.view.View
import android.view.ViewGroup
import android.widget.ImageView
import androidx.core.os.BundleCompat
import androidx.core.view.GestureDetectorCompat
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.github.chrisbanes.photoview.PhotoViewAttacher
import com.keylesspalace.tusky.R
import com.keylesspalace.tusky.ViewMediaActivity
import com.keylesspalace.tusky.databinding.FragmentViewImageBinding
import com.keylesspalace.tusky.entity.Attachment
import com.keylesspalace.tusky.util.hide
import com.keylesspalace.tusky.util.viewBinding
import com.keylesspalace.tusky.util.visible
import com.ortiz.touchview.OnTouchCoordinatesListener
import com.ortiz.touchview.TouchImageView
import io.reactivex.rxjava3.subjects.BehaviorSubject
import kotlin.math.abs
@ -48,10 +54,8 @@ class ViewImageFragment : ViewMediaFragment() {
fun onPhotoTap()
}
private var _binding: FragmentViewImageBinding? = null
private val binding get() = _binding!!
private val binding by viewBinding(FragmentViewImageBinding::bind)
private lateinit var attacher: PhotoViewAttacher
private lateinit var photoActionsListener: PhotoActionsListener
private lateinit var toolbar: View
private var transition = BehaviorSubject.create<Unit>()
@ -84,8 +88,7 @@ class ViewImageFragment : ViewMediaFragment() {
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View {
toolbar = (requireActivity() as ViewMediaActivity).toolbar
this.transition = BehaviorSubject.create()
_binding = FragmentViewImageBinding.inflate(inflater, container, false)
return binding.root
return inflater.inflate(R.layout.fragment_view_image, container, false)
}
@SuppressLint("ClickableViewAccessibility")
@ -108,95 +111,139 @@ class ViewImageFragment : ViewMediaFragment() {
}
}
attacher = PhotoViewAttacher(binding.photoView).apply {
// This prevents conflicts with ViewPager
setAllowParentInterceptOnEdge(true)
val singleTapDetector = GestureDetectorCompat(
requireContext(),
object : GestureDetector.SimpleOnGestureListener() {
override fun onDown(e: MotionEvent) = true
override fun onSingleTapConfirmed(e: MotionEvent): Boolean {
photoActionsListener.onPhotoTap()
return false
}
}
)
// Clicking outside the photo closes the viewer.
setOnOutsidePhotoTapListener { photoActionsListener.onDismiss() }
setOnClickListener { onMediaTap() }
binding.photoView.setOnTouchCoordinatesListener(object : OnTouchCoordinatesListener {
/** Y coordinate of the last single-finger drag */
var lastDragY: Float? = null
/* 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)) {
override fun onTouchCoordinate(view: View, event: MotionEvent, bitmapPoint: PointF) {
singleTapDetector.onTouchEvent(event)
// Two fingers have gone down after a single finger drag. Finish the drag
if (event.pointerCount == 2 && lastDragY != null) {
onGestureEnd(view)
lastDragY = null
}
// Stop the parent view from handling touches if either (a) the user has 2+
// fingers on the screen, or (b) the image has been zoomed in, and can be scrolled
// horizontally in both directions.
//
// This stops things like ViewPager2 from trying to intercept a left/right swipe
// and ensures that the image does not appear to "stick" to the screen as different
// views fight over who should be handling the swipe.
//
// If the view can be scrolled in one direction it's OK to let the parent intercept,
// which allows the user to swipe between images even if one or more of them have
// been zoomed in.
if (event.pointerCount >= 2 || view.canScrollHorizontally(1) && view.canScrollHorizontally(-1)) {
when (event.action) {
MotionEvent.ACTION_DOWN, MotionEvent.ACTION_MOVE -> {
view.parent.requestDisallowInterceptTouchEvent(true)
}
MotionEvent.ACTION_UP -> {
view.parent.requestDisallowInterceptTouchEvent(false)
}
}
return
}
// The user is dragging the image around
if (event.pointerCount == 1) {
// If the image is zoomed then the swipe-to-dismiss functionality is disabled
if ((view as TouchImageView).isZoomed) return
// The user's finger just went down, start recording where they are dragging from
if (event.action == MotionEvent.ACTION_DOWN) {
lastDragY = event.rawY
return
}
// The user is dragging the un-zoomed image to possibly fling it up or down
// to dismiss.
if (event.action == MotionEvent.ACTION_MOVE) {
// lastDragY may be null; e.g., the user was performing a two-finger drag,
// and has lifted one finger. In this case do nothing
lastDragY ?: return
// Compute the Y offset of the drag, and scale/translate the photoview
// accordingly.
val diff = event.rawY - lastDragY!!
if (view.translationY != 0f || abs(diff) > 40) {
// Drag has definitely started, stop the parent from interfering
view.parent.requestDisallowInterceptTouchEvent(true)
view.translationY += diff
val scale = (-abs(view.translationY) / 720 + 1).coerceAtLeast(0.5f)
view.scaleY = scale
view.scaleX = scale
lastDragY = event.rawY
}
return
}
// The user has finished dragging. Allow the parent to handle touch events if
// appropriate, and end the gesture.
if (event.action == MotionEvent.ACTION_UP || event.action == MotionEvent.ACTION_CANCEL) {
view.parent.requestDisallowInterceptTouchEvent(false)
if (lastDragY != null) onGestureEnd(view)
lastDragY = null
return
}
}
}
/**
* Handle the end of the user's gesture.
*
* If the user was previously dragging, and the image has been dragged a sufficient
* distance then we are done. Otherwise, animate the image back to its starting position.
*/
private fun onGestureEnd(view: View) {
if (abs(view.translationY) > 180) {
photoActionsListener.onDismiss()
result = true
} else {
view.animate().translationY(0f).scaleX(1f).start()
}
result
}
}
var lastY = 0f
binding.photoView.setOnTouchListener { v, event ->
// This part is for scaling/translating on vertical move.
// We use raw coordinates to get the correct ones during scaling
if (event.action == MotionEvent.ACTION_DOWN) {
lastY = event.rawY
} else if (event.pointerCount == 1 &&
attacher.scale == 1f &&
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 (binding.photoView.translationY != 0f || abs(diff) > 40) {
binding.photoView.translationY += (diff)
val scale = (-abs(binding.photoView.translationY) / 720 + 1).coerceAtLeast(0.5f)
binding.photoView.scaleY = scale
binding.photoView.scaleX = scale
lastY = event.rawY
return@setOnTouchListener true
}
} else if (event.action == MotionEvent.ACTION_UP || event.action == MotionEvent.ACTION_CANCEL) {
onGestureEnd()
}
attacher.onTouch(v, event)
}
})
finalizeViewSetup(url, attachment?.previewUrl, description)
}
private fun onGestureEnd() {
if (_binding == null) {
return
}
if (abs(binding.photoView.translationY) > 180) {
photoActionsListener.onDismiss()
} else {
binding.photoView.animate().translationY(0f).scaleX(1f).scaleY(1f).start()
}
}
private fun onMediaTap() {
photoActionsListener.onPhotoTap()
}
override fun onToolbarVisibilityChange(visible: Boolean) {
if (_binding == null || !userVisibleHint) {
return
}
if (!userVisibleHint) return
isDescriptionVisible = showingDescription && visible
val alpha = if (isDescriptionVisible) 1.0f else 0.0f
binding.captionSheet.animate().alpha(alpha)
.setListener(object : AnimatorListenerAdapter() {
override fun onAnimationEnd(animation: Animator) {
if (_binding != null) {
binding.captionSheet.visible(isDescriptionVisible)
}
view ?: return
binding.captionSheet.visible(isDescriptionVisible)
animation.removeListener(this)
}
})
.start()
}
override fun onDestroyView() {
override fun onStop() {
super.onStop()
Glide.with(this).clear(binding.photoView)
}
override fun onDestroyView() {
transition.onComplete()
_binding = null
super.onDestroyView()
}
@ -270,7 +317,7 @@ class ViewImageFragment : ViewMediaFragment() {
photoActionsListener.onBringUp()
}
// Hide progress bar only on fail request from internet
if (!isCacheRequest && _binding != null) binding.progressBar.hide()
if (!isCacheRequest) binding.progressBar.hide()
// We don't want to overwrite preview with null when main image fails to load
return !isCacheRequest
}
@ -283,9 +330,7 @@ class ViewImageFragment : ViewMediaFragment() {
dataSource: DataSource,
isFirstResource: Boolean
): Boolean {
if (_binding != null) {
binding.progressBar.hide() // Always hide the progress bar on success
}
binding.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
@ -303,10 +348,6 @@ class ViewImageFragment : ViewMediaFragment() {
.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()
}
}
return true

View File

@ -6,7 +6,7 @@
android:orientation="vertical"
android:paddingBottom="0dp">
<com.github.chrisbanes.photoview.PhotoView
<com.ortiz.touchview.TouchImageView
android:id="@+id/imageDescriptionView"
android:layout_width="match_parent"
android:layout_height="0dp"

View File

@ -7,7 +7,7 @@
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" />

View File

@ -47,8 +47,8 @@ robolectric = "4.10.3"
rxandroid3 = "3.0.2"
rxjava3 = "3.1.6"
rxkotlin3 = "3.0.1"
photoview = "2.3.0"
sparkbutton = "4.1.0"
touchimageview = "3.4"
truth = "1.1.5"
turbine = "1.0.0"
unified-push = "2.1.1"
@ -127,7 +127,6 @@ mockwebserver = { module = "com.squareup.okhttp3:mockwebserver", version.ref = "
networkresult-calladapter = { module = "at.connyduck:networkresult-calladapter", version.ref = "networkresult-calladapter" }
okhttp-core = { module = "com.squareup.okhttp3:okhttp", version.ref = "okhttp" }
okhttp-logging-interceptor = { module = "com.squareup.okhttp3:logging-interceptor", version.ref = "okhttp" }
photoview = { module = "com.github.chrisbanes:PhotoView", version.ref = "photoview" }
retrofit-adapter-rxjava3 = { module = "com.squareup.retrofit2:adapter-rxjava3", version.ref = "retrofit" }
retrofit-converter-gson = { module = "com.squareup.retrofit2:converter-gson", version.ref = "retrofit" }
retrofit-core = { module = "com.squareup.retrofit2:retrofit", version.ref = "retrofit" }
@ -136,6 +135,7 @@ rxjava3-android = { module = "io.reactivex.rxjava3:rxandroid", version.ref = "rx
rxjava3-core = { module = "io.reactivex.rxjava3:rxjava", version.ref = "rxjava3" }
rxjava3-kotlin = { module = "io.reactivex.rxjava3:rxkotlin", version.ref = "rxkotlin3" }
sparkbutton = { module = "com.github.connyduck:sparkbutton", version.ref = "sparkbutton" }
touchimageview = { module = "com.github.MikeOrtiz:TouchImageView", version.ref = "touchimageview" }
truth = { module = "com.google.truth:truth", version.ref = "truth" }
turbine = { module = "app.cash.turbine:turbine", version.ref = "turbine" }
unified-push = { module = "com.github.UnifiedPush:android-connector", version.ref = "unified-push" }