android-pdf-viewer在android studio应用问题说明

android-pdf-viewer在android studio应用问题说明

小白一枚，之前一直是做.NET开发的，最近需要弄一个新闻app，能力有限，只能借助HTML5 WebAPP+android studio来完成这项工作。
android studio主要用WebView来加载发布好的WebApp，打包生产APP。
其中由于显示一些pdf文档，所以研究了一下，记录一下心得，同时也希望帮助到新手们。

android 显示网络pdf，基本原理：先将pdf文件通过DownloadManager下载到手机sdk某个文件夹中，然后通过android-pdf-viewer插件进行显示。

android-pdf-viewer插件可以直接到github上下载，地址：https://github.com/barteksc/AndroidPdfViewer
或者直接到发布好的页面下载：https://github.com/barteksc/AndroidPdfViewer/releases
我下载的是：AndroidPdfViewer-2.1.0版本zip包

将下载AndroidPdfViewer-2.1.0包解压出来，再你的app项目中，打开 File -> New -> Import Module 选择到刚才解压的文件夹

本人目录是：D:\AndroidStudioProjects\AndroidPdfViewer-2.1.0\android-pdf-viewer

完成后，回提示先ERROR：
Error:Plugin with id ‘com.github.dcendents.android-maven’ not found.

解决方法：
点击你的工程Gradle Scripts目录下的bulid.gradle (Project:你的工程名)
在
buildscript {
repositories {
jcenter()
}
dependencies {
classpath ‘com.android.tools.build:gradle:2.0.0’
}
}
中dependencies的下添加 classpath ‘com.github.dcendents:android-maven-gradle-plugin:1.3’，
Mark Modules之后，出现新的ERROR：
Error:Plugin with id ‘com.jfrog.bintray’ not found.
此时同样在dependencies下添加：classpath “com.jfrog.bintray.gradle:gradle-bintray-plugin:1.0”
再次Mark Modules就不会报错了。
先就可以开始使用 android-pdf-viewer 插件了，

别忘记引用权限问题哦

 <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
    <uses-permission android:name="android.permission.INTERNET" />

    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.DOWNLOAD_WITHOUT_NOTIFICATION"/>
    <uses-permission android:name="android.permission.INSTALL_PACKAGES" />

先代码为项目中report activity.java,实现了接收另外一个activity跳转过来同时传递参数pdf地址，然后通过DownloadManager下载完成之后，显示pdf。

package cn.cgrs.myphone;

import android.app.DownloadManager;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.SharedPreferences;
import android.database.Cursor;
import android.net.Uri;
import android.os.Environment;
import android.preference.PreferenceManager;
import android.provider.OpenableColumns;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.webkit.MimeTypeMap;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.widget.TextView;
import android.widget.Toast;

import com.github.barteksc.pdfviewer.listener.OnLoadCompleteListener;
import com.github.barteksc.pdfviewer.listener.OnPageChangeListener;
import com.github.barteksc.pdfviewer.scroll.DefaultScrollHandle;
import com.shockwave.pdfium.PdfDocument;

import java.io.File;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.List;

public class Report extends AppCompatActivity  implements OnPageChangeListener, OnLoadCompleteListener {

    private com.github.barteksc.pdfviewer.PDFView pdfView ;
    private TextView textView;

    private DownloadManager downloadManager;
    private SharedPreferences prefs;
    private static String DL_ID = "downloadId";

    Integer pageNumber = 0;

    String pdfFileName = "yyy.pdf";

    Uri uri;

    String AUrl;

    private Boolean isDown = false;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_report);

        Intent intent = getIntent();   // 获取 Intent

        AUrl  = intent.getStringExtra("url"); // 获取 String 值
        Log.e("接收url:",AUrl);

        //AUrl = "http://www.tyyq.cn/xhsapp/download/a03790b7f27243eeada01537a2ce2f77.pdf";

        String[] exts = AUrl.split("/");
        pdfFileName = exts[exts.length-1];
        Log.e("pdf文件名：",pdfFileName);

        String pdfName = Environment.getExternalStorageDirectory() +
                "/download";

        File file = new File(pdfName, pdfFileName);

        pdfView = (com.github.barteksc.pdfviewer.PDFView)findViewById(R.id.pdfView);
        textView = (TextView) findViewById(R.id.textView);

        if(file.exists()){
            Log.e("Tip：","报告已经存在！");
            //文件已经存在，则直接显示
            uri = Uri.fromFile(file);
            displayFromUri(uri);
            textView.setVisibility(View.GONE);
            pdfView.setVisibility(View.VISIBLE);
        }
        else{

            isDown = true;

        }

        //Log.e("prefs字符串：",prefs.toString());
    }

    @Override
    protected void onResume(){

        super.onResume();

        if(isDown)
        {
            try{
                Log.e("Tip：","报告不存在,需要下载！");
                DL_ID = pdfFileName;
                //文件不存在需要先下载
                downloadManager = (DownloadManager)getSystemService(DOWNLOAD_SERVICE);
                prefs = PreferenceManager.getDefaultSharedPreferences(this);

                StartReport();
            }
            catch (Exception ex)
            {
                Toast.makeText(this, ex.getMessage(), Toast.LENGTH_LONG).show();
            }
        }
    }

    @Override
    protected void onPause() {
        // TODO Auto-generated method stub
        super.onPause();
        //unregisterReceiver(receiver);

        try {
            unregisterReceiver(receiver);
        } catch (IllegalArgumentException e) {
            if (e.getMessage().contains("Receiver not registered")) {
                // Ignore this exception. This is exactly what is desired
            } else {
                // unexpected, re-throw
                throw e;
            }
        }
    }

    //下载报告启动函数
    protected void StartReport() {
        // TODO Auto-generated method stub

        if(!prefs.contains(DL_ID) || true) {  //
           // String url = AUrl;
            //Log.e("-----",AUrl);

            //String[] exts = url.split("/");
            //pdfFileName = "97b49c0822c14a01b3ebc273679bc6bf.pdf";
                    //exts[exts.length-1];

            String url = AUrl;//"http://www.tyyq.cn/RollImage/11.pdf";
            Log.e("开始下载url：",AUrl);

            //开始下载
            Uri resource = Uri.parse(encodeGB(url));
            DownloadManager.Request request = new DownloadManager.Request(resource);
            request.setAllowedNetworkTypes(DownloadManager.Request.NETWORK_MOBILE | DownloadManager.Request.NETWORK_WIFI);
            request.setAllowedOverRoaming(false);
            //设置文件类型
            MimeTypeMap mimeTypeMap = MimeTypeMap.getSingleton();
            String mimeString = mimeTypeMap.getMimeTypeFromExtension(MimeTypeMap.getFileExtensionFromUrl(url));
            request.setMimeType(mimeString);
            //在通知栏中显示
            //设置通知栏标题
            request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE);
            request.setDescription("舆情报告正在下载");
            //request.setShowRunningNotification(true);
            request.setVisibleInDownloadsUi(true);
            //sdcard的目录下的download文件夹
            request.setDestinationInExternalPublicDir("/download/", pdfFileName);
            request.setTitle("舆情报告");
            long id = downloadManager.enqueue(request);
            //保存id
            prefs.edit().putLong(DL_ID, id).commit();
        } else {

            Log.e("提示：","下载已经开始，检查状态");
            //下载已经开始，检查状态
            queryDownloadStatus();
        }

        registerReceiver(receiver, new IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE));
    }

    /**
     * 如果服务器不支持中文路径的情况下需要转换url的编码。
     * @param string
     * @return
     */
    public String encodeGB(String string)
    {
        //转换中文编码
        String split[] = string.split("/");
        for (int i = 1; i < split.length; i++) {
            try {
                split[i] = URLEncoder.encode(split[i], "GB2312");
            } catch (UnsupportedEncodingException e) {
                e.printStackTrace();
            }
            split[0] = split[0]+"/"+split[i];
        }
        split[0] = split[0].replaceAll("\\+", "%20");//处理空格
        return split[0];
    }

    private BroadcastReceiver receiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            //这里可以取得下载的id，这样就可以知道哪个文件下载完成了。适用与多个下载任务的监听
            Log.v("intent", ""+intent.getLongExtra(DownloadManager.EXTRA_DOWNLOAD_ID, 0));
            queryDownloadStatus();
        }
    };

    private void queryDownloadStatus() {
        DownloadManager.Query query = new DownloadManager.Query();
        query.setFilterById(prefs.getLong(DL_ID, 0));
        Cursor c = downloadManager.query(query);
        if(c.moveToFirst()) {
            int status = c.getInt(c.getColumnIndex(DownloadManager.COLUMN_STATUS));
            switch(status) {
                case DownloadManager.STATUS_PAUSED:
                    Log.v("down", "STATUS_PAUSED");
                case DownloadManager.STATUS_PENDING:
                    Log.v("down", "STATUS_PENDING");
                case DownloadManager.STATUS_RUNNING:
                    //正在下载，不做任何事情
                    Log.v("down", "STATUS_RUNNING");
                    break;
                case DownloadManager.STATUS_SUCCESSFUL:
                    //完成
                    Log.v("down", "下载完成");

                    String pdfName = Environment.getExternalStorageDirectory() +
                            "/download";

                    File file = new File(pdfName, pdfFileName);
                    uri = Uri.fromFile(file);

                    Log.e("----",uri.toString());

                    displayFromUri(uri);

                    textView.setVisibility(View.GONE);
                    pdfView.setVisibility(View.VISIBLE);
                    break;
                case DownloadManager.STATUS_FAILED:
                    //清除已下载的内容，重新下载
                    Log.v("down", "STATUS_FAILED");
                    downloadManager.remove(prefs.getLong(DL_ID, 0));
                    prefs.edit().clear().commit();
                    break;
            }
        }
    }


    /*pdf显示函数集合*/

    private void displayFromUri(Uri urii) {
        //pdfFileName = getFileName(urii);

        pdfView.fromUri(urii)
                .defaultPage(pageNumber)
                .onPageChange(this)
                .enableAnnotationRendering(true)
                .onLoad(this)
                .scrollHandle(new DefaultScrollHandle(this))
                .load();
    }


    public void onResult(int resultCode, Intent intent) {
        if (resultCode == RESULT_OK) {
            uri = intent.getData();
            displayFromUri(uri);
        }
    }

    @Override
    public void onPageChanged(int page, int pageCount) {
        pageNumber = page;
        setTitle(String.format("%s %s / %s", pdfFileName, page + 1, pageCount));
    }

    public String getFileName(Uri uri) {
        String result = null;
        if (uri.getScheme().equals("content")) {
            Cursor cursor = getContentResolver().query(uri, null, null, null, null);
            try {
                if (cursor != null && cursor.moveToFirst()) {
                    result = cursor.getString(cursor.getColumnIndex(OpenableColumns.DISPLAY_NAME));
                }
            } finally {
                if (cursor != null) {
                    cursor.close();
                }
            }
        }
        if (result == null) {
            result = uri.getLastPathSegment();
        }
        return result;
    }

    @Override
    public void loadComplete(int nbPages) {
        PdfDocument.Meta meta = pdfView.getDocumentMeta();

        printBookmarksTree(pdfView.getTableOfContents(), "-");

    }

    public void printBookmarksTree(List<PdfDocument.Bookmark> tree, String sep) {
        for (PdfDocument.Bookmark b : tree) {

            // Log.e(TAG, String.format("%s %s, p %d", sep, b.getTitle(), b.getPageIdx()));

            if (b.hasChildren()) {
                printBookmarksTree(b.getChildren(), sep + "-");
            }
        }
    }

}