PDFTron内存泄漏缩放

Question

我正在使用PDFTron，它可以很好地和花花公子来处理PDF格式的东西。我用xamarin制作了一个应用程序，人们开放了很多pdf来签名。这样也可以。

然而，当一个人放大和缩小时，问题就开始了。然后记忆突然开始填满。放大几个文档后应用程序崩溃..

任何人都知道发生了什么？

这是所有魔法发生的活动：

初始化PDFViewCtrl

    private PDFViewCtrl _mPdfViewCtrl;
    SetupViewer(filePath);

按下后退按钮时

    public override void OnBackPressed()
    {
        base.OnBackPressed();
        _syncManager = null;
        DisposePdfCtrl();

        Finish();

    }

保存文档

_mPdfViewCtrl.Doc.Save(filePath, 0);

设置Pdf视图

private void SetupViewer(string filePath)
    {
        try
        {

        PDFNet.SetDefaultDiskCachingEnabled(true);
        PDFNet.SetViewerCache(100 * 1024 * 1024, false);
        }
        catch (pdftron.Common.PDFNetException ex)
        {
        Logger.log(Title, "Failed to setup viewer");


        }

        try
        {

        Logger.log(Title, $"Setting up pdf viewer");
        SetContentView(Resource.Layout.PdfView);

        var toolbar = FindViewById<Toolbar>(Resource.Id.toolbar);
        SetSupportActionBar(toolbar);

        SupportActionBar.Title = "Sign Document";

        Logger.log(Title, $"Toolbar is setup.");
        _mPdfViewCtrl = FindViewById<PDFViewCtrl>(Resource.Id.pdfviewctrl);

        _mPdfViewCtrl.PagePresentationMode = PDFViewCtrl.PagePresentationModes.e_single_page;
        _mPdfViewCtrl.PageViewMode = PDFViewCtrl.PageViewModes.e_fit_page;
        _mPdfViewCtrl.PageRefViewMode = PDFViewCtrl.PageViewModes.e_fit_page;
        _mPdfViewCtrl.SetHighlightFields(true);

        Logger.log(Title, $"Opening file in viewer: {filePath}");

        var docToOpen = new PDFDoc(filePath);
        docToOpen.InitStdSecurityHandler("");

        if (!_allowChange)
        {
            docToOpen.FlattenAnnotations();
        }

        Logger.log(Title, "setting file to pdf viewer");
        _mPdfViewCtrl.Doc = docToOpen;




        var toolManager = new ToolManager(_mPdfViewCtrl);
        Logger.log(Title, "setting file to pdf viewer");
        _mPdfViewCtrl.ToolManager = toolManager;



        }
        catch (Exception ex)
        {
        Logger.log(Title, $"Error while setting up pdf view: {ex.Message}");
        }
    }

暂停

    protected override void OnPause()
    {
        base.OnPause();
        DisposePdfCtrl();
    }

On Resume

    protected override async void OnResume()
    {
        base.OnResume();
        try
        {
        if (!_busy)
        {

            _mPdfViewCtrl?.Resume();
        }
        }
        catch (ObjectDisposedException)
        {
        SetupViewer(filePath);
        }
    }

On Destroy

protected override void OnDestroy()
{
    base.OnDestroy();
    DisposePdfCtrl();

}

处置

bool disposed = false;
private void DisposePdfCtrl()
{
    if (_disposing)
    return;

    _disposing = true;
    if (disposed) return;
        try
        {
            var oldTool = _mPdfViewCtrl.ToolManager;
            var oldDoc = _mPdfViewCtrl.Doc;

            _mPdfViewCtrl.Doc.Unlock();
            _mPdfViewCtrl?.PurgeMemory();

            _mPdfViewCtrl?.CloseDoc();
            _mPdfViewCtrl?.CloseTool();


            oldDoc?.Dispose();
            oldTool?.Dispose();

            _mPdfViewCtrl?.Dispose();
            _mPdfViewCtrl = null;
            _syncManager = null;
            GC.Collect();
            this.Dispose();

        } catch (Exception ex)
        {

        }
        disposed = true;
    _disposing = false;
}

低记忆

public override void OnLowMemory()
{
    base.OnLowMemory();
    Logger.log(Title, "Low on memory");
    _mPdfViewCtrl?.PurgeMemory();
}