无法在新活动中打开 pdf [英] Not able to open pdf in new activity

问题描述

我正在为我的项目使用 这个 github 源代码.我在 assets 文件夹中有一个包含 10 个元素和 10 个不同 PDF 的列表视图.在 1 个活动中，我使用 listview 和 onItemClickListener 如下所示:

I'm using this github source for my project. I've a listview with 10 elements and 10 different PDFs in assets folder. In 1 activity, I'm using listview and onItemClickListener as shown below:

ArrayAdapter arrayAdapter = new ArrayAdapter<>(this, R.layout.activity_policy_list, mobileArray);
        ListView listView = (ListView) findViewById(R.id.policy_list);
        listView.setAdapter(arrayAdapter);
        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
                Intent intent = new Intent(PolicyActivity.this, PdfViewerActivity.class);
                intent.putExtra(PdfViewerActivity.EXTRA_PDFFILENAME, getAssets() + "/dummy.pdf");
                startActivity(intent);
            }
        });  

PdfViewerActivity 类的代码如下:

package com.dell.eventapp.ui.activity;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

import com.dell.eventapp.R;

public class PdfViewerActivity extends net.sf.andpdf.pdfviewer.PdfViewerActivity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_pdf_viewer);
    }

    @Override
    public int getPreviousPageImageResource() {
        return R.drawable.left_arrow;
    }

    @Override
    public int getNextPageImageResource() {
        return R.drawable.right_arrow;
    }

    @Override
    public int getZoomInImageResource() {
        return R.drawable.zoom_in;
    }

    @Override
    public int getZoomOutImageResource() {
        return R.drawable.zoom_out;
    }

    @Override
    public int getPdfPasswordLayoutResource() {
        return 0;
    }

    @Override
    public int getPdfPageNumberResource() {
        return 0;
    }

    @Override
    public int getPdfPasswordEditField() {
        return 0;
    }

    @Override
    public int getPdfPasswordOkButton() {
        return 0;
    }

    @Override
    public int getPdfPasswordExitButton() {
        return 0;
    }

    @Override
    public int getPdfPageNumberEditField() {
        return 0;
    }
}

当我单击列表视图中的任何项目时，应打开新活动，并应在新活动中查看 PDF.当我运行我的代码时，我总是收到这个错误:

When I click on any item in list view, new activity should open up and PDF should be viewed in new activity. When I run my code, I always get this error:

02-23 18:19:48.033 8982-8982/com.dell.eventapp I/PDFVIEWER: ST='file 'android.content.res.AssetManager@817d40c/dummy.pdf' not found'  

我在 github 存储库中遇到了这个这个问题问题.它说无法从 Assets 文件夹加载 PDF.您应该在打开之前将其复制到 SD 卡上.我该如何解决?

I came across this this issue in github repo's issues. It says that PDF cannot be loaded from Assets folder. You should copy it on sdcard before opening it. How can I work around it?

推荐答案

intent.putExtra(PdfViewerActivity.EXTRA_PDFFILENAME, getAssets() + "/dummy.pdf");

getAssets() 返回一个 AssetManager.getAssets() + "/dummy.pdf" 在 AssetManager 实例上调用 toString()，然后附加 /dummy.pdf 到它.这就是为什么你会得到 android.content.res.AssetManager@817d40c/dummy.pdf.AssetManager 上的 toString() 不会以某种方式神奇地为您提供资产的文件系统路径...部分原因是资产不是设备上的文件.

getAssets() returns an AssetManager. getAssets() + "/dummy.pdf" calls toString() on the AssetManager instance, and then appends /dummy.pdf to it. This is why you wind up with android.content.res.AssetManager@817d40c/dummy.pdf. toString() on AssetManager does not somehow magically give you a filesystem path to an asset... in part because assets are not files on the device.

我该如何解决?

要么:

• 按照该问题中的说明将资产复制到文件中，或者

• Follow the instructions in that issue and copy the asset to a file, or

修改该库以支持资产，或

Modify that library to support an asset, or

不要使用那个库，而是使用其他支持从资产显示 PDF 的东西

Do not use that library, but use something else that does support displaying a PDF from an asset

FWIW，我有示例应用程序演示了 <代码>pdf.js 和 pdfium 用于显示来自资产的 PDF.

FWIW, I have sample apps demonstrating the use of pdf.js and pdfium for displaying PDFs from assets.

这篇关于无法在新活动中打开 pdf的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！