Merge pull request #146 from kizitonwose/dev

Release 0.3.4

library/build.gradle

@@ -33,6 +33,7 @@ android {
 dependencies {
     implementation fileTree(dir: 'libs', include: ['*.jar'])
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$versions.kotlin_lang"
+    implementation "androidx.core:core-ktx:$versions.androidx_core_ktx"
 
     // Expose ThreeTenABP so library users can use it directly.
     api "com.jakewharton.threetenabp:threetenabp:$versions.threetenabp"
@@ -50,7 +51,7 @@ dependencies {
     api "androidx.recyclerview:recyclerview:$versions.recyclerview"
 
     testImplementation "junit:junit:$versions.junit"
-    testImplementation('org.threeten:threetenbp:1.3.7') {
+    testImplementation('org.threeten:threetenbp:1.4.2') {
         // Use threetenBP library for tests as context will
         // not be available to initialise threetenABP
         exclude group: 'com.jakewharton.threetenabp', module: 'threetenabp'

library/src/main/java/com/kizitonwose/calendarview/CalendarView.kt

@@ -6,7 +6,6 @@ import android.view.View.MeasureSpec.UNSPECIFIED
 import android.view.ViewGroup
 import androidx.annotation.Px
 import androidx.recyclerview.widget.DiffUtil
-import androidx.recyclerview.widget.PagerSnapHelper
 import androidx.recyclerview.widget.RecyclerView
 import com.kizitonwose.calendarview.model.*
 import com.kizitonwose.calendarview.ui.*
@@ -198,6 +197,15 @@ open class CalendarView : RecyclerView {
             }
         }
 
+    /**
+     * The duration in milliseconds of the animation used to adjust the CalendarView's
+     * height when [scrollMode] is [ScrollMode.PAGED] and the CalendarView's height is
+     * set to `wrap_content`. The height change happens when the CalendarView scrolls to
+     * a month which has less or more rows than the previous one. Default value is 200.
+     * To disable the animation, set this value to zero.
+     */
+    var wrappedPageHeightAnimationDuration = 200
+
     private var startMonth: YearMonth? = null
     private var endMonth: YearMonth? = null
     private var firstDayOfWeek: DayOfWeek? = null
@@ -234,6 +242,10 @@ open class CalendarView : RecyclerView {
         maxRowCount = a.getInt(R.styleable.CalendarView_cv_maxRowCount, maxRowCount)
         monthViewClass = a.getString(R.styleable.CalendarView_cv_monthViewClass)
         hasBoundaries = a.getBoolean(R.styleable.CalendarView_cv_hasBoundaries, hasBoundaries)
+        wrappedPageHeightAnimationDuration = a.getInt(
+            R.styleable.CalendarView_cv_wrappedPageHeightAnimationDuration,
+            wrappedPageHeightAnimationDuration
+        )
         a.recycle()
     }
 
@@ -563,7 +575,7 @@ open class CalendarView : RecyclerView {
         }
     }
 
-    private val pagerSnapHelper = PagerSnapHelper()
+    private val pagerSnapHelper = CalenderPageSnapHelper()
 
     /**
      * Setup the CalendarView. You can call this any time to change the

library/src/main/java/com/kizitonwose/calendarview/ui/CalendarAdapter.kt

@@ -1,5 +1,6 @@
 package com.kizitonwose.calendarview.ui
 
+import android.animation.ValueAnimator
 import android.content.Context
 import android.graphics.Rect
 import android.os.Build
@@ -8,6 +9,7 @@ import android.view.ViewGroup
 import android.widget.LinearLayout
 import androidx.annotation.LayoutRes
 import androidx.core.view.ViewCompat
+import androidx.core.view.updateLayoutParams
 import androidx.recyclerview.widget.RecyclerView
 import com.kizitonwose.calendarview.CalendarView
 import com.kizitonwose.calendarview.model.*
@@ -164,6 +166,7 @@ internal class CalendarAdapter(
 
     private var visibleMonth: CalendarMonth? = null
     private var calWrapsHeight: Boolean? = null
+    private var initialLayout = true
     fun notifyMonthScrollListenerIfNeeded() {
         // Guard for cv.post() calls and other callbacks which use this method.
         if (!isAttached) return
@@ -194,12 +197,14 @@ internal class CalendarAdapter(
                 // calculating height and uses the tallest one of the three meaning that the current index's
                 // view will end up having a blank space at the bottom unless the immediate previous and next
                 // indices are also missing the last row. I think there should be a better way to fix this.
-                if (calView.isHorizontal && calView.scrollMode == ScrollMode.PAGED) {
+                // New: Also fixes issue where the calendar does not wrap each month's height when in vertical,
+                // paged mode and just matches parent's height instead.
+                if (calView.scrollMode == ScrollMode.PAGED) {
                     val calWrapsHeight = calWrapsHeight ?: (calView.layoutParams.height == LP.WRAP_CONTENT).also {
                         // We modify the layoutParams so we save the initial value set by the user.
                         calWrapsHeight = it
                     }
-                    if (calWrapsHeight.not()) return // Bug only happens when the CalenderView wraps its height.
+                    if (!calWrapsHeight) return // Bug only happens when the CalenderView wraps its height.
                     val visibleVH =
                         calView.findViewHolderForAdapterPosition(visibleItemPos) as? MonthViewHolder ?: return
                     val newHeight = visibleVH.headerView?.height.orZero() +
@@ -208,13 +213,16 @@ internal class CalendarAdapter(
                         // by checking the number of visible(non-empty) rows.
                         visibleMonth.weekDays.size * calView.dayHeight +
                         visibleVH.footerView?.height.orZero()
-                    if (calView.layoutParams.height != newHeight) {
-                        calView.layoutParams = calView.layoutParams.apply {
-                            this.height = newHeight
-                        }
-                        visibleVH.itemView.layoutParams = visibleVH.itemView.layoutParams.apply {
-                            this.height = newHeight
+                    if (calView.height != newHeight) {
+                        ValueAnimator.ofInt(calView.height, newHeight).apply {
+                            duration = if (initialLayout) 0 else calView.wrappedPageHeightAnimationDuration.toLong()
+                            addUpdateListener {
+                                calView.updateLayoutParams { height = it.animatedValue as Int }
+                                visibleVH.itemView.requestLayout()
+                            }
+                            start()
                         }
+                        if (initialLayout) initialLayout = false
                     }
                 }
             }

library/src/main/java/com/kizitonwose/calendarview/ui/CalenderPageSnapHelper.kt

@@ -0,0 +1,50 @@
+package com.kizitonwose.calendarview.ui
+
+import android.view.View
+import androidx.recyclerview.widget.OrientationHelper
+import androidx.recyclerview.widget.PagerSnapHelper
+import androidx.recyclerview.widget.RecyclerView
+
+class CalenderPageSnapHelper : PagerSnapHelper() {
+
+    /**
+     * The default implementation of this method in [PagerSnapHelper.calculateDistanceToFinalSnap] uses the distance
+     * between the target view center vs RecyclerView center as final snap distance. This does not always give the
+     * desired result for calendar usage. For example in a vertical calendar when the RecyclerView is taller than
+     * the item view(e.g two or more visible months), we don't actually want the item view's center to be at the
+     * center of the RecyclerView when it snaps but instead we want the item view and RecyclerView top(in vertical)
+     * or left(in horizontal) to match at the end of the snap.
+     */
+    override fun calculateDistanceToFinalSnap(layoutManager: RecyclerView.LayoutManager, targetView: View): IntArray {
+        return IntArray(2).apply {
+            this[0] = if (layoutManager.canScrollHorizontally())
+                distanceToStart(targetView, getHorizontalHelper(layoutManager)) else 0
+
+            this[1] = if (layoutManager.canScrollVertically())
+                distanceToStart(targetView, getVerticalHelper(layoutManager)) else 0
+        }
+    }
+
+    private fun distanceToStart(targetView: View, helper: OrientationHelper): Int {
+        val childStart = (helper.getDecoratedStart(targetView))
+        val containerStart = helper.startAfterPadding
+        return childStart - containerStart
+    }
+
+    private lateinit var verticalHelper: OrientationHelper
+    private lateinit var horizontalHelper: OrientationHelper
+
+    private fun getVerticalHelper(layoutManager: RecyclerView.LayoutManager): OrientationHelper {
+        if (!::verticalHelper.isInitialized || verticalHelper.layoutManager != layoutManager) {
+            verticalHelper = OrientationHelper.createVerticalHelper(layoutManager)
+        }
+        return verticalHelper
+    }
+
+    private fun getHorizontalHelper(layoutManager: RecyclerView.LayoutManager): OrientationHelper {
+        if (!::horizontalHelper.isInitialized || horizontalHelper.layoutManager != layoutManager) {
+            horizontalHelper = OrientationHelper.createHorizontalHelper(layoutManager)
+        }
+        return horizontalHelper
+    }
+}

library/src/main/res/values/attrs.xml

@@ -70,5 +70,11 @@
             <enum name="continuous" value="0" />
             <enum name="paged" value="1" />
         </attr>
+
+        <!-- The duration in milliseconds of the animation used to adjust the CalendarView's
+        height when `scrollMode` is `paged` and the CalendarView height is set to `wrap_content`.
+        The height change happens when the CalendarView scrolls to a month which has less or more
+        rows than the previous one. Default value is 200. To disable the animation, set this value to zero. -->
+        <attr name="cv_wrappedPageHeightAnimationDuration" format="integer" />
     </declare-styleable>
 </resources>