Reflow document mode in Android

<com.pdftron.pdf.controls.ReflowControl
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/reflow_pager"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

If you want to map each original color to a new color (for example for handling night mode) you need to pass an OnPostProcessColorListener listener to the ReflowControl.

To do so, you can provide an OnPostProcessColorListener listener when setting up the ReflowControl:

ReflowControl reflowControl = (ReflowControl) findViewById(R.id.reflow_pager);
reflowControl.setup(pdfDoc, mOnPostProcessColorListener);

For example, OnPostProcessColorListener can be defined by PDFViewCtrl as:

final ReflowControl.OnPostProcessColorListener mOnPostProcessColorListener =
    new ReflowControl.OnPostProcessColorListener() {
        @Override
        public ColorPt getPostProcessedColor(ColorPt cp) {
            if (mPDFViewCtrl != null) {
                return mPDFViewCtrl.getPostProcessedColor(cp);
            }
            return cp;
        }
    };

Alternatively you can set a listener:

ReflowControl reflowControl = (ReflowControl) findViewById(R.id.reflow_pager);
reflowControl.setup(pdfDoc);
reflowControl.setOnPostProcessColorListener(mOnPostProcessColorListener);

It is not necessary to use a reflow pager to create a reflowable layout of PDF pages. It is also possible to extract the reflowable layout by creating an HTML file from a specific page of the document using the ReflowProcessor class. The first step is to let the Core know you are going to use reflow by calling initialize(). Please note that this method clears all existing reflowable data. Thus, preferably put this call in your Application or Activity.

When reflow processor has been initialized, it is possible to turn reflow on by calling getReflow(Page, RequestHandler, Object) and passing a RequestHandler callback in order to be notified once the reflowable HTML file is ready::

void getReflowPage(PDFViewCtrl pdfViewCtrl, final int pageNum) throws Exception {
    final PDFDoc doc = pdfViewCtrl.getDoc();
    pdfViewCtrl.docLockRead(new PDFViewCtrl.LockRunnable() {
        @Override
        public void run() throws Exception {
            Page page = doc.getPage(pageNum);
            ReflowProcessor.getReflow(page, mRequestHandler, pageNum);
        }
    });
}

RequestHandler mRequestHandler = new RequestHandler(new RequestHandler.RequestHandlerCallback() {
    @Override
    public void RequestHandlerProc(RequestHandler.JobRequestResult result, String outFilename, Object customData) {
        if (result == RequestHandler.JobRequestResult.FINISHED) {
            // int pageNum = (int) customData;
            // A reflowable HTML file with a page number of pageNum is located at outFilename
        }
    }
});

To cancel all reflow requests, call cancelAllRequests().

Finally, if you want to clear all HTML files created in the cache, you may need to call clearCache().