rtl for android?

[Abdulrahman-Alanazi1]

What react-native version are you using?
0.74.5

What react-native-pdf version are you using?
6.7.5

What platform does your issue occur on? (android/ios/both)
android

Describe your issue as precisely as possible :
I have a PDF file that was written in Arabic, and I would like to swipe the pages from left to right. I do not want to arrange the pages like p3-p2-p1 I just want to reverse the swiping of the pages in android, is it possible?

[irwant]

That is possible, but it needs some native code in java to make it happen. I have tested, and it works.

Step 1 :
open file PdfManager.java in /node_modules/react-native-pdf/android/src/main/java/org/wonday/pdf/PdfManager.java

change :

@Override
    public void setEnableRTL(PdfView view, boolean value) {
        // NOOP on Android
    }

to :

@ReactProp(name = "enableRTL")
    public void setEnableRTL(PdfView view, boolean enableRTL) {
        pdfView.setEnableRTL(enableRTL);
    }

Step 2 :
open PdfView.java in same folder
add:

import java.io.IOException;
import android.graphics.pdf.PdfRenderer;
import android.os.ParcelFileDescriptor;

add declaration under class PdfView

 private boolean enableRTL = false;
 private int totalPages = 0;
 private int[] pagesArrays;

add method :

public void setEnableRTL(boolean enableRTL){
        this.enableRTL= enableRTL;
        
     }

add some code inside method drawPdf() under showLog :

File file = new File(this.path);

         if (file.exists()) {
             try {
                 ParcelFileDescriptor fileDescriptor = ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY);
                 PdfRenderer pdfRenderer = new PdfRenderer(fileDescriptor);
                 this.totalPages = pdfRenderer.getPageCount();
                 int[] pagesArrays = new int[this.totalPages];
                 if (this.enableRTL) {
                    for (int i = totalPages-1; i>=0; i--) {
                        pagesArrays[i] =totalPages-1- i;
                    }
                    this.pagesArrays = pagesArrays;
                    this.page=totalPages-1;
                }else{
                    for (int i = totalPages-1; i>=0; i--) {
                        pagesArrays[i] = i;
                    }
                    this.pagesArrays = pagesArrays;
                    this.page=totalPages-totalPages;
                }
             } catch (IOException e) {
                 Log.e("error", "error read PDF", e);
             }
         }

adding and change value .defaultPage(this.page-1) :
from :

configurator.defaultPage(this.page-1)
                .swipeHorizontal(this.horizontal)
                .onPageChange(this)
                .onLoad(this)

to :

configurator
                 .pages(this.pagesArrays) //set the pages
                 .defaultPage(this.page) // change value
                 .swipeHorizontal(this.horizontal)
                 .onPageChange(this)
                 .onLoad(this)

[irwant]

and if you want to have a bookmark function

add some code to PdfView.java :
declare : private int bookmarks = 0;

adding on the setPage(int page) :

public void setPage(int page) {
         this.page = page>1?page:1;
         this.bookmarks = page; //add this line
     }

and change :

File file = new File(this.path);

         if (file.exists()) {
             try {
                 ParcelFileDescriptor fileDescriptor = ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY);
                 PdfRenderer pdfRenderer = new PdfRenderer(fileDescriptor);
                 this.totalPages = pdfRenderer.getPageCount();
                 int[] pagesArrays = new int[this.totalPages];
                 if (this.enableRTL) {
                    for (int i = totalPages-1; i>=0; i--) {
                        pagesArrays[i] =totalPages-1- i;
                    }
                    this.pagesArrays = pagesArrays;
                    this.page=totalPages-this.bookmarks; //change to this new code
                }else{
                    //delete old code to this new code
                    this.pagesArrays = null;
                    this.page=this.bookmarks-1;
                }
             } catch (IOException e) {
                 Log.e("error", "error read PDF", e);
             }
         }

for the save bookmarked, you can do on your React code

[irwant]

and change :

File file = new File(this.path);

         if (file.exists()) {
             try {
                 ParcelFileDescriptor fileDescriptor = ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY);
                 PdfRenderer pdfRenderer = new PdfRenderer(fileDescriptor);
                 this.totalPages = pdfRenderer.getPageCount();
                 int[] pagesArrays = new int[this.totalPages];
                 if (this.enableRTL) {
                    for (int i = totalPages-1; i>=0; i--) {
                        pagesArrays[i] =totalPages-1- i;
                    }
                    this.pagesArrays = pagesArrays;
                    this.page=totalPages-this.bookmarks; //change to this new code
                }else{
                    //delete old code to this new code
                    this.pagesArrays = null;
                    this.page=this.bookmarks-1;
                }
             } catch (IOException e) {
                 Log.e("error", "error read PDF", e);
             }
         }

for the save bookmarked, you can do on your React code

EDIT :

if (this.enableRTL) {
                     for (int i = totalPages-1; i>=0; i--) {
                         pagesArrays[i] =totalPages-1- i;
                     }
                     if(this.page>1){
                        this.page= this.bookmarks-1;
                    }else{
                        this.page=totalPages; // make it jump to the first page
                    }
                     this.pagesArrays = pagesArrays;
                 }