Single page scrolling

android-pdf-viewer/build.gradle

@@ -1,3 +1,4 @@
+//apply plugin: 'java'
 apply plugin: 'com.android.library'
 
 ext {
@@ -26,7 +27,7 @@ ext {
 
 android {
     compileSdkVersion 25
-    buildToolsVersion '25.0.3'
+    //buildToolsVersion '25.0.3'
 
     defaultConfig {
         minSdkVersion 11

android-pdf-viewer/src/main/java/com/github/barteksc/pdfviewer/AnimationManager.java

@@ -24,6 +24,8 @@
 import android.view.animation.DecelerateInterpolator;
 import android.widget.OverScroller;
 
+import com.github.barteksc.pdfviewer.util.PageViewType;
+
 
 /**
  * This manager is used by the PDFView to launch animations.
@@ -171,6 +173,8 @@ public void onAnimationCancel(Animator animation) {
 
         @Override
         public void onAnimationEnd(Animator animation) {
+            if (pdfView.getPageViewType() == PageViewType.SINGLE && pdfView.getZoom() == pdfView.getMinZoom())
+                pdfView.jumpTo(pdfView.getCurrentPage(), true);
             pdfView.loadPages();
             hideHandle();
         }

android-pdf-viewer/src/main/java/com/github/barteksc/pdfviewer/DecodingAsyncTask.java

@@ -48,7 +48,7 @@ protected Throwable doInBackground(Void... params) {
         try {
             PdfDocument pdfDocument = docSource.createDocument(pdfView.getContext(), pdfiumCore, password);
             pdfFile = new PdfFile(pdfiumCore, pdfDocument, pdfView.getPageFitPolicy(), getViewSize(),
-                    userPages, pdfView.isSwipeVertical(), pdfView.getSpacingPx());
+                    userPages, pdfView.isSwipeVertical(), pdfView.getSpacingPx(), pdfView.getPageViewType());
             return null;
         } catch (Throwable t) {
             return t;

android-pdf-viewer/src/main/java/com/github/barteksc/pdfviewer/DragPinchManager.java

@@ -24,6 +24,7 @@
 
 import com.github.barteksc.pdfviewer.model.LinkTapEvent;
 import com.github.barteksc.pdfviewer.scroll.ScrollHandle;
+import com.github.barteksc.pdfviewer.util.PageViewType;
 import com.shockwave.pdfium.PdfDocument;
 import com.shockwave.pdfium.util.SizeF;
 
@@ -178,6 +179,8 @@ public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float d
     }
 
     private void onScrollEnd(MotionEvent event) {
+        if (pdfView.getPageViewType() == PageViewType.SINGLE && !pdfView.isZooming())
+          pdfView.jumpTo(pdfView.getCurrentPage(), true);
         pdfView.loadPages();
         hideHandle();
     }

android-pdf-viewer/src/main/java/com/github/barteksc/pdfviewer/PDFView.java

@@ -56,6 +56,7 @@
 import com.github.barteksc.pdfviewer.util.Constants;
 import com.github.barteksc.pdfviewer.util.FitPolicy;
 import com.github.barteksc.pdfviewer.util.MathUtils;
+import com.github.barteksc.pdfviewer.util.PageViewType;
 import com.github.barteksc.pdfviewer.util.Util;
 import com.shockwave.pdfium.PdfDocument;
 import com.shockwave.pdfium.PdfiumCore;
@@ -167,6 +168,9 @@ enum ScrollDir {
     /** Policy for fitting pages to screen */
     private FitPolicy pageFitPolicy = FitPolicy.WIDTH;
 
+    /** How the page should move when swiping. Continuously or one at a time */
+    private PageViewType pageViewType = PageViewType.CONTINUOUS;
+
     private int defaultPage = 0;
 
     /** True if should scroll through pages vertically instead of horizontally */
@@ -275,6 +279,8 @@ public void jumpTo(int page, boolean withAnimation) {
 
         page = pdfFile.determineValidPageNumberFrom(page);
         float offset = -pdfFile.getPageOffset(page, zoom);
+        if (getPageViewType() == PageViewType.SINGLE)
+            offset = page == 0 ? 0 : -pdfFile.getPageOffset(page, zoom) + spacingPx;
         if (swipeVertical) {
             if (withAnimation) {
                 animationManager.startYAnimation(currentYOffset, offset);
@@ -706,6 +712,9 @@ void loadComplete(PdfFile pdfFile) {
 
         callbacks.callOnLoadComplete(pdfFile.getPagesCount());
 
+        if (getPageViewType() == PageViewType.SINGLE)
+            spacingPx = pdfFile.getSpacingPx();
+
         jumpTo(defaultPage, false);
     }
 
@@ -1077,6 +1086,14 @@ public FitPolicy getPageFitPolicy() {
         return pageFitPolicy;
     }
 
+    private void setPageViewType(PageViewType pageViewType) {
+        this.pageViewType = pageViewType;
+    }
+
+    public PageViewType getPageViewType() {
+        return pageViewType;
+    }
+
     public boolean doRenderDuringScale() {
         return renderDuringScale;
     }
@@ -1183,6 +1200,8 @@ public class Configurator {
 
         private FitPolicy pageFitPolicy = FitPolicy.WIDTH;
 
+        private PageViewType pageViewType = PageViewType.CONTINUOUS;
+
         private Configurator(DocumentSource documentSource) {
             this.documentSource = documentSource;
         }
@@ -1292,6 +1311,11 @@ public Configurator pageFitPolicy(FitPolicy pageFitPolicy) {
             return this;
         }
 
+        public Configurator pageViewType(PageViewType pageViewType) {
+            this.pageViewType = pageViewType;
+            return this;
+        }
+
         public void load() {
             if (!hasSize) {
                 waitingDocumentConfigurator = this;
@@ -1317,6 +1341,7 @@ public void load() {
             PDFView.this.enableAntialiasing(antialiasing);
             PDFView.this.setSpacing(spacing);
             PDFView.this.setPageFitPolicy(pageFitPolicy);
+            PDFView.this.setPageViewType(pageViewType);
 
             if (pageNumbers != null) {
                 PDFView.this.load(documentSource, password, pageNumbers);

android-pdf-viewer/src/main/java/com/github/barteksc/pdfviewer/PdfFile.java

@@ -23,6 +23,7 @@
 import com.github.barteksc.pdfviewer.exception.PageRenderingException;
 import com.github.barteksc.pdfviewer.util.FitPolicy;
 import com.github.barteksc.pdfviewer.util.PageSizeCalculator;
+import com.github.barteksc.pdfviewer.util.PageViewType;
 import com.shockwave.pdfium.PdfDocument;
 import com.shockwave.pdfium.PdfiumCore;
 import com.shockwave.pdfium.util.Size;
@@ -58,20 +59,22 @@ class PdfFile {
     /** Calculated document length (width or height, depending on swipe mode) */
     private float documentLength = 0;
     private final FitPolicy pageFitPolicy;
+    private final PageViewType pageViewType;
     /**
      * The pages the user want to display in order
      * (ex: 0, 2, 2, 8, 8, 1, 1, 1)
      */
     private int[] originalUserPages;
 
     PdfFile(PdfiumCore pdfiumCore, PdfDocument pdfDocument, FitPolicy pageFitPolicy, Size viewSize, int[] originalUserPages,
-            boolean isVertical, int spacing) {
+            boolean isVertical, int spacing, PageViewType viewType) {
         this.pdfiumCore = pdfiumCore;
         this.pdfDocument = pdfDocument;
         this.pageFitPolicy = pageFitPolicy;
         this.originalUserPages = originalUserPages;
         this.isVertical = isVertical;
         this.spacingPx = spacing;
+        this.pageViewType = viewType;
         setup(viewSize);
     }
 
@@ -113,7 +116,7 @@ public void recalculatePageSizes(Size viewSize) {
         }
 
         prepareDocLen();
-        preparePagesOffset();
+        preparePagesOffset(viewSize);
     }
 
     public int getPagesCount() {
@@ -159,11 +162,27 @@ private void prepareDocLen() {
         documentLength = length + spacing;
     }
 
-    private void preparePagesOffset() {
+    private void preparePagesOffset(Size viewSize) {
         pageOffsets.clear();
+
+        if (pageViewType == PageViewType.SINGLE && getPagesCount() > 0)
+        {
+            if (pageFitPolicy == FitPolicy.WIDTH || pageFitPolicy == FitPolicy.BOTH)
+                spacingPx = 0;
+            else {
+                SizeF pageSize = getPageSize(0);
+                int offset = (int)(viewSize.getWidth() - pageSize.getWidth()) / 2;
+                spacingPx = offset+1;
+                prepareDocLen();
+                documentLength += spacingPx*2;
+            }
+        }
+
         float offset = 0;
         for (int i = 0; i < getPagesCount(); i++) {
             float spacing = i * spacingPx;
+            if (pageViewType == PageViewType.SINGLE)
+                spacing = (i+1) * spacingPx;
             pageOffsets.add(offset + spacing);
             SizeF size = pageSizes.get(i);
             offset += isVertical ? size.getHeight() : size.getWidth();
@@ -207,6 +226,11 @@ public int getPageAtOffset(float offset, float zoom) {
         return --currentPage >= 0 ? currentPage : 0;
     }
 
+    public int getSpacingPx()
+    {
+        return spacingPx;
+    }
+
     public boolean openPage(int pageIndex) throws PageRenderingException {
         int docPage = documentPage(pageIndex);
         if (docPage < 0) {

android-pdf-viewer/src/main/java/com/github/barteksc/pdfviewer/util/PageViewType.java

@@ -0,0 +1,9 @@
+package com.github.barteksc.pdfviewer.util;
+
+/**
+ * Created by starnaus on 12/22/2017.
+ */
+
+public enum PageViewType {
+    CONTINUOUS, SINGLE
+}

build.gradle

@@ -4,7 +4,7 @@ buildscript {
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:2.3.3'
+        classpath 'com.android.tools.build:gradle:3.0.1'
         classpath 'com.jfrog.bintray.gradle:gradle-bintray-plugin:1.7.3'
         classpath 'com.github.dcendents:android-maven-gradle-plugin:1.5'
     }

sample/build.gradle

@@ -13,11 +13,11 @@ repositories {
 }
 
 apply plugin: 'com.android.application'
-apply plugin: 'android-apt'
+//apply plugin: 'android-apt'
 
 android {
     compileSdkVersion 25
-    buildToolsVersion "25.0.3"
+    //buildToolsVersion "25.0.3"
 
     defaultConfig {
         minSdkVersion 11
@@ -31,6 +31,7 @@ android {
 dependencies {
     compile project(':android-pdf-viewer')
     compile 'com.android.support:appcompat-v7:25.3.1'
-    provided 'org.androidannotations:androidannotations:4.0.0'
+    annotationProcessor 'org.androidannotations:androidannotations:4.0.0'
+    //provided 'org.androidannotations:androidannotations:4.0.0'
     compile 'org.androidannotations:androidannotations-api:4.0.0'
 }

sample/src/main/java/com/github/barteksc/sample/PDFViewActivity.java

@@ -35,6 +35,7 @@
 import com.github.barteksc.pdfviewer.listener.OnPageErrorListener;
 import com.github.barteksc.pdfviewer.scroll.DefaultScrollHandle;
 import com.github.barteksc.pdfviewer.util.FitPolicy;
+import com.github.barteksc.pdfviewer.util.PageViewType;
 import com.shockwave.pdfium.PdfDocument;
 
 import org.androidannotations.annotations.AfterViews;
@@ -47,6 +48,8 @@
 
 import java.util.List;
 
+import static android.content.res.Configuration.ORIENTATION_LANDSCAPE;
+
 @EActivity(R.layout.activity_main)
 @OptionsMenu(R.menu.options)
 public class PDFViewActivity extends AppCompatActivity implements OnPageChangeListener, OnLoadCompleteListener,
@@ -102,7 +105,7 @@ void launchPicker() {
 
     @AfterViews
     void afterViews() {
-        pdfView.setBackgroundColor(Color.LTGRAY);
+        pdfView.setBackgroundColor(Color.BLACK);
         if (uri != null) {
             displayFromUri(uri);
         } else {
@@ -114,7 +117,7 @@ void afterViews() {
     private void displayFromAsset(String assetFileName) {
         pdfFileName = assetFileName;
 
-        pdfView.fromAsset(SAMPLE_FILE)
+        /*pdfView.fromAsset(SAMPLE_FILE)
                 .defaultPage(pageNumber)
                 .onPageChange(this)
                 .enableAnnotationRendering(true)
@@ -123,7 +126,23 @@ private void displayFromAsset(String assetFileName) {
                 .spacing(10) // in dp
                 .onPageError(this)
                 .pageFitPolicy(FitPolicy.BOTH)
-                .load();
+                .load();*/
+
+        PDFView.Configurator configurator = pdfView.fromAsset(SAMPLE_FILE);
+        configurator.defaultPage(pageNumber);
+        configurator.onPageChange(this);
+        configurator.enableAnnotationRendering(true);
+        configurator.onLoad(this);
+        //configurator.scrollHandle(new DefaultScrollHandle(this));
+        //configurator.spacing(300);
+        configurator.onPageError(this);
+        configurator.swipeHorizontal(true);
+        configurator.pageViewType(PageViewType.SINGLE);
+        if (getResources().getConfiguration().orientation == ORIENTATION_LANDSCAPE)
+            configurator.pageFitPolicy(FitPolicy.HEIGHT);
+        else
+            configurator.pageFitPolicy(FitPolicy.WIDTH);
+        configurator.load();
     }
 
     private void displayFromUri(Uri uri) {