Merge pull request #121 from AlanCheen/feature/sticky-header

Feature/sticky header

app/src/main/java/me/yifeiyuan/flapdev/ConfigMenuView.kt

@@ -2,6 +2,7 @@ package me.yifeiyuan.flapdev
 
 import android.content.Context
 import android.view.LayoutInflater
+import android.view.View
 import android.widget.FrameLayout
 import android.widget.SeekBar
 import androidx.recyclerview.widget.RecyclerView
@@ -33,8 +34,8 @@ class ConfigMenuView : FrameLayout {
         //1 Grid
         //2 Staggered
         //3 IndexedStaggered
-        binding.layoutManagerGroup.setOnCheckedChangeListener { group, checkedId ->
-            when (checkedId) {
+        val layoutManagerClickListener = OnClickListener { v ->
+            when (v.id) {
                 R.id.linear -> {
                     callback?.onLayoutManagerChanged(0)
                 }
@@ -47,8 +48,16 @@ class ConfigMenuView : FrameLayout {
                 R.id.indexedStaggered -> {
                     callback?.onLayoutManagerChanged(3)
                 }
+                R.id.stickyHeader->{
+                    callback?.onLayoutManagerChanged(4)
+                }
             }
         }
+        binding.linear.setOnClickListener(layoutManagerClickListener)
+        binding.grid.setOnClickListener(layoutManagerClickListener)
+        binding.staggered.setOnClickListener(layoutManagerClickListener)
+        binding.indexedStaggered.setOnClickListener(layoutManagerClickListener)
+        binding.stickyHeader.setOnClickListener(layoutManagerClickListener)
 
         binding.clearAll.setOnClickListener {
             callback?.onClearAllData()

app/src/main/java/me/yifeiyuan/flapdev/FlapApplication.kt

@@ -3,7 +3,10 @@ package me.yifeiyuan.flapdev
 import android.app.Application
 import android.util.Log
 import android.widget.Toast
+import androidx.core.view.get
 import androidx.multidex.MultiDexApplication
+import androidx.recyclerview.widget.RecyclerView
+import androidx.viewpager2.widget.ViewPager2
 import me.yifeiyuan.flap.Flap
 import me.yifeiyuan.flap.apt.delegates.*
 import me.yifeiyuan.flap.dsl.adapterHook
@@ -17,6 +20,12 @@ import me.yifeiyuan.flapdev.components.*
 class FlapApplication : MultiDexApplication() {
 
     companion object {
+
+        val ViewPager2.recyclerView: RecyclerView
+            get() {
+                return this[0] as RecyclerView
+            }
+
         var application: Application? = null
             set(value) {
                 field = value

app/src/main/java/me/yifeiyuan/flapdev/SingleScrollDirection.kt

@@ -0,0 +1,72 @@
+package me.yifeiyuan.flapdev
+
+import android.view.MotionEvent
+import androidx.recyclerview.widget.RecyclerView
+import java.lang.Math.abs
+
+/**
+ * Created by 程序亦非猿 on 2022/10/18.
+ */
+
+fun RecyclerView.enforceSingleScrollDirection() {
+    val enforcer = SingleScrollDirectionEnforcer()
+    addOnItemTouchListener(enforcer)
+    addOnScrollListener(enforcer)
+}
+
+private class SingleScrollDirectionEnforcer : RecyclerView.OnScrollListener(), RecyclerView.OnItemTouchListener {
+
+    private var scrollState = RecyclerView.SCROLL_STATE_IDLE
+    private var scrollPointerId = -1
+    private var initialTouchX = 0
+    private var initialTouchY = 0
+    private var dx = 0
+    private var dy = 0
+
+    override fun onInterceptTouchEvent(rv: RecyclerView, e: MotionEvent): Boolean {
+        when (e.actionMasked) {
+            MotionEvent.ACTION_DOWN -> {
+                scrollPointerId = e.getPointerId(0)
+                initialTouchX = (e.x + 0.5f).toInt()
+                initialTouchY = (e.y + 0.5f).toInt()
+            }
+            MotionEvent.ACTION_POINTER_DOWN -> {
+                val actionIndex = e.actionIndex
+                scrollPointerId = e.getPointerId(actionIndex)
+                initialTouchX = (e.getX(actionIndex) + 0.5f).toInt()
+                initialTouchY = (e.getY(actionIndex) + 0.5f).toInt()
+            }
+            MotionEvent.ACTION_MOVE -> {
+                val index = e.findPointerIndex(scrollPointerId)
+                if (index >= 0 && scrollState != RecyclerView.SCROLL_STATE_DRAGGING) {
+                    val x = (e.getX(index) + 0.5f).toInt()
+                    val y = (e.getY(index) + 0.5f).toInt()
+                    dx = x - initialTouchX
+                    dy = y - initialTouchY
+                }
+            }
+        }
+        return false
+    }
+
+    override fun onTouchEvent(rv: RecyclerView, e: MotionEvent) {}
+
+    override fun onRequestDisallowInterceptTouchEvent(disallowIntercept: Boolean) {}
+
+    override fun onScrollStateChanged(recyclerView: RecyclerView, newState: Int) {
+        val oldState = scrollState
+        scrollState = newState
+        if (oldState == RecyclerView.SCROLL_STATE_IDLE && newState == RecyclerView.SCROLL_STATE_DRAGGING) {
+            recyclerView.layoutManager?.let { layoutManager ->
+                val canScrollHorizontally = layoutManager.canScrollHorizontally()
+                val canScrollVertically = layoutManager.canScrollVertically()
+                if (canScrollHorizontally != canScrollVertically) {
+                    if ((canScrollHorizontally && abs(dy) > abs(dx))
+                            || (canScrollVertically && abs(dx) > abs(dy))) {
+                        recyclerView.stopScroll()
+                    }
+                }
+            }
+        }
+    }
+}

app/src/main/java/me/yifeiyuan/flapdev/StickyHeaders.java

@@ -0,0 +1,28 @@
+package me.yifeiyuan.flapdev;
+
+import android.view.View;
+
+/**
+ * Created by 程序亦非猿 on 2022/10/17.
+ */
+interface StickyHeaders {
+
+    boolean isStickyHeader(int position);
+
+    interface ViewSetup {
+        /**
+         * Adjusts any necessary properties of the {@code holder} that is being used as a sticky header.
+         *
+         * {@link #teardownStickyHeaderView(View)} will be called sometime after this method
+         * and before any other calls to this method go through.
+         */
+        void setupStickyHeaderView(View stickyHeader);
+
+        /**
+         * Reverts any properties changed in {@link #setupStickyHeaderView(View)}.
+         *
+         * Called after {@link #setupStickyHeaderView(View)}.
+         */
+        void teardownStickyHeaderView(View stickyHeader);
+    }
+}