Cleaning up code and tweaking (disabling) some default drawing settings on RecyclerView

Author: maxieds

AndroidFilePickerLightLibrary/src/main/java/com/maxieds/androidfilepickerlightlibrary/DisplayAdapters.java

@@ -120,6 +120,9 @@ public int getItemCount() {
 
         @Override
         public long getItemId(int posIndex) {
+            if(posIndex < fileListData.size()) {
+                return fileListData.get(posIndex).hashCode();
+            }
             return posIndex;
         }
 

AndroidFilePickerLightLibrary/src/main/java/com/maxieds/androidfilepickerlightlibrary/DisplayFragments.java

@@ -99,7 +99,6 @@ private void setViewportMaxFilesCount(int viewportFilesCap) {
     }
 
     public boolean resetViewportMaxFilesCount(View parentViewContainer) {
-        Log.i(LOGTAG, "resetViewportMaxFilesCount");
         if(!viewportCapacityMesaured) {
             int viewportDisplayHeight = parentViewContainer.getMeasuredHeight();
             if(fileItemDisplayHeight == 0 || viewportDisplayHeight == 0) {
@@ -108,6 +107,9 @@ public boolean resetViewportMaxFilesCount(View parentViewContainer) {
             setViewportMaxFilesCount((int) Math.floor((double) viewportDisplayHeight / fileItemDisplayHeight));
             Log.i(LOGTAG, String.format("DELAYED RESPONSE: VP Height = %d, FItemDisp Height = %d   ====>  %d",
                     viewportDisplayHeight, fileItemDisplayHeight, getViewportMaxFilesCount()));
+            getMainRecyclerView().setItemViewCacheSize(2 * getViewportMaxFilesCount());
+            getMainRecyclerView().setDrawingCacheEnabled(true);
+            getMainRecyclerView().setDrawingCacheQuality(View.DRAWING_CACHE_QUALITY_HIGH);
             viewportCapacityMesaured = true;
         }
         return true;
@@ -278,7 +280,6 @@ public static void resetLayout(View layoutContainer, DisplayTypes.FileType fileI
             selectionBox.setTag(displayPosition);
             selectionBox.setOnCheckedChangeListener(new DisplayAdapters.OnSelectListener());
 
-
         }
 
     }

AndroidFilePickerLightLibrary/src/main/java/com/maxieds/androidfilepickerlightlibrary/FileChooserRecyclerView.java

@@ -36,6 +36,7 @@ This program (the AndroidFilePickerLight library) is free software written by
 import androidx.recyclerview.widget.LinearLayoutManager;
 import androidx.recyclerview.widget.LinearSmoothScroller;
 import androidx.recyclerview.widget.RecyclerView;
+import androidx.recyclerview.widget.SimpleItemAnimator;
 
 import java.util.Locale;
 
@@ -60,8 +61,7 @@ public FileChooserRecyclerView(Context context, AttributeSet attrSet, int defSty
 
     public void setupRecyclerViewLayout() {
 
-        setHasFixedSize(false);
-        //setItemViewCacheSize(0);
+        setHasFixedSize(true);
         setNestedScrollingEnabled(false);
         LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(
                 ViewGroup.LayoutParams.MATCH_PARENT,
@@ -72,12 +72,14 @@ public void setupRecyclerViewLayout() {
         setLayoutManager((FileChooserRecyclerView.LayoutManager) rvLayoutManager);
         addItemDecoration(new FileChooserRecyclerView.CustomDividerItemDecoration(R.drawable.rview_file_item_divider));
         //addOnItemTouchListener(...);
+        //((SimpleItemAnimator) getItemAnimator()).setSupportsChangeAnimations(false);
+        getItemAnimator().setChangeDuration(0);
 
     }
 
-    // We want it to move when flung and be responsive, but keep a constant rate of movement:
-    private static final int FLING_VELOCITY_DAMPENAT = 850;
-
+    // We want it to move when flung and be responsive, but keep an approximately
+    // constant rate of movement through the items:
+    private static final int FLING_VELOCITY_DAMPENAT = 500;
 
     @Override
     public boolean fling(int velocityX, int velocityY) {
@@ -88,11 +90,6 @@ public boolean fling(int velocityX, int velocityY) {
         return super.fling(0, scaledVelocityY);
     }
 
-    /*@Override
-    public void smoothScrollToPosition(int indexPos) {
-        getLayoutManager().smoothScrollToPosition(this, new RecyclerView.State(), indexPos);
-    }*/
-
     public interface RecyclerViewSlidingContextWindow {
 
         void setWeightBufferSize(int size);
@@ -120,7 +117,7 @@ public LayoutManager(Context layoutCtx) {
             setOrientation(LinearLayoutManager.VERTICAL);
             setAutoMeasureEnabled(true);
             setReverseLayout(false);
-            setStackFromEnd(true); // ???
+            setStackFromEnd(true);
             setSmoothScrollbarEnabled(true);
             localStaticInst = this;
         }
@@ -130,13 +127,8 @@ public boolean isAutoMeasureEnabled() {
             return true;
         }
 
-        /*// intent is to speed it up for the prefetch thread smooth scrolling:
+        /*
         public static final float SCROLLER_MILLISECONDS_PER_INCH = 16.0f; // larger values slow it down, 25.0 ~ default behavior
-
-        private int intendedNextScrollPos;
-        private LinearSmoothScroller linearSmoothScroller;
-        private RecyclerView scrollInvokingRV;
-
         @Override
         public void smoothScrollToPosition(RecyclerView recyclerView, State state, int position) {
             scrollInvokingRV = recyclerView;
@@ -149,19 +141,7 @@ protected float calculateSpeedPerPixel(DisplayMetrics displayMetrics) {
             linearSmoothScroller.setTargetPosition(position);
             startSmoothScroll(linearSmoothScroller);
         }
-
-        public boolean completeLastSmoothScroll() {
-            if(linearSmoothScroller == null || intendedNextScrollPos < 0 ||
-                    intendedNextScrollPos >= getItemCount() || scrollInvokingRV == null) {
-                return false;
-            }
-            else if(!linearSmoothScroller.isRunning()) {
-                return false;
-            }
-            scrollInvokingRV.stopScroll();
-            scrollInvokingRV.scrollToPosition(intendedNextScrollPos);
-            return true;
-        }*/
+        */
 
     }
 

AndroidFilePickerLightLibrary/src/main/java/com/maxieds/androidfilepickerlightlibrary/PrefetchFilesUpdater.java

@@ -19,6 +19,7 @@ This program (the AndroidFilePickerLight library) is free software written by
 
 import android.os.AsyncTask;
 import android.util.Log;
+import android.view.View;
 
 import java.util.ArrayList;
 import java.util.HashMap;
@@ -343,7 +344,7 @@ else if(updateDataType.equals(UpdateDataStruct.UpdateDataType.PREPEND_DATA_AT_TO
     }
 
     private static final long THREAD_INIT_PAUSE_TIMEOUT = 125; // Milliseconds
-    private static final long THREAD_PAUSE_TIMEOUT = 500; //250; // Milliseconds
+    private static final long THREAD_PAUSE_TIMEOUT = 550; // Milliseconds
 
     @Override
     public void run() {