Android PDFRenderer 编译问题

Question

我在API 5.0上使用PDFRenderer创建一个应用程序我不得不在外部添加pdf渲染器.jar现在它也显示以下错误 - "构造函数 PDFRenderer（ParcelFileDescriptor） 未定义"谁能帮忙...这对我来说是新的..

Answer 1

使用 PDFRenderer(ParcelFileDescriptor input)其中输入是可查找的文件描述符。

Pdf 渲染器基本上将文件描述符作为其参数，而您没有提供任何描述符。

请参阅开发人员页面https://developer.android.com/reference/android/graphics/pdf/PdfRenderer.html

Answer 2

private void render() {
    try {
        Log.e("In render()","render");
        imageView = (ImageView) findViewById(R.id.imageView);
        int REQ_WIDTH = 1;
        int REQ_HEIGHT = 1;
        REQ_WIDTH = imageView.getWidth();
        REQ_HEIGHT = imageView.getHeight();
        Log.e("In render2()","render2");
        System.out.println("req_height"+REQ_HEIGHT+" "+"REQ_WIDTH"+REQ_WIDTH);
       Bitmap bitmap = Bitmap.createBitmap(REQ_WIDTH, REQ_HEIGHT, Bitmap.Config.ARGB_4444);

        File file = new File("/home/woigames/Desktop/PDF/DebitCards-tc.pdf");
        PDFRenderer renderer = new PDFRenderer(ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY));
        if(renderer != null)
        {
            Log.i("renderer not null","check");
        }
        else 
        {
            Log.i("renderer is null","check");
        }
        final int pageCount = renderer.getPageCount();
        if (currentPage < 0) {
            currentPage = 0;
        } else if (currentPage > renderer.getPageCount()) {
            currentPage = renderer.getPageCount() - 1;
        }
        Matrix m = imageView.getImageMatrix();
        Rect rect = new Rect(0, 0, REQ_WIDTH, REQ_HEIGHT);
        renderer.openPage(currentPage).render(bitmap, rect, m, PdfRenderer.Page.RENDER_MODE_FOR_DISPLAY);
        imageView.setImageMatrix(m);
        imageView.setImageBitmap(bitmap);
        imageView.invalidate();
        renderer.close();
    } catch (Exception e) {
        e.printStackTrace();
    }

Answer 3

在清单中添加 API 级别 21 并尝试 .Lolipop pdf 渲染器需要最低 SDK 级别 21

<uses-sdk android:minSdkVersion="21" />