Android使用TBS浏览器加载pdf等文件

项目结构

技术方案

TBS的其它优点，可以自行搜索网上其它资料，很多。

加载文件核心类是 TbsReaderView，腾讯文档没有写，所以需要查找网上资料。

TBS目前只支持加载本地文件。所以远程文件需要先下载，后用TBS加载文件显示。

负责加载和显示文件的界面，离开本界面之后务必需要销毁，否则再次加载文件无法加载成功，会一直显示加载文件进度条。

关键代码：

mTbsReaderView.onStop()

;//销毁界面的时候一定要加上，否则后面加载文件会发生异常。

完整项目源码

package com.yifeng.sample.tbs;
import android.app.DownloadManager;
import android.app.DownloadManager.Request;
import android.content.Intent;
import android.database.ContentObserver;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.os.Handler;
import android.support.v7.app.AppCompatActivity;
import android.text.TextUtils;
import android.util.Log;
import android.view.View;
import android.view.ViewGroup.LayoutParams;
import android.widget.Button;
import android.widget.RelativeLayout;

import com.tencent.smtt.sdk.TbsReaderView;
import com.tencent.smtt.sdk.TbsReaderView.ReaderCallback;

import java.io.File;

public class MainActivity extends AppCompatActivity implements ReaderCallback {

private TbsReaderView mTbsReaderView;
private Button mDownloadBtn;

private DownloadManager mDownloadManager;
private long mRequestId;
private DownloadObserver mDownloadObserver;
private String mFileUrl = "http://www.beijing.gov.cn/zhuanti/ggfw/htsfwbxzzt/shxfl/fw/P020150720516332194302.doc";
private String mFileName;

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

mTbsReaderView = new TbsReaderView(this, this);
mDownloadBtn = (Button) findViewById(R.id.btn_download);
RelativeLayout rootRl = (RelativeLayout) findViewById(R.id.rl_root);
rootRl.addView(mTbsReaderView, new RelativeLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));

mFileName = parseName(mFileUrl);
if (isLocalExist()) {
mDownloadBtn.setText("打开文件");
}

if (isLocalExist()) {
mDownloadBtn.setVisibility(View.GONE);
displayFile();
} else {
startDownload();
}
}

@Override
public void onBackPressed() {
startActivity(new Intent(MainActivity.this,IndexActivity.class));
finish();//不关掉此界面，之后加载文件会无法加载
}

public void onClickDownload(View v) {
//    if (isLocalExist()) {
//      mDownloadBtn.setVisibility(View.GONE);
//      displayFile();
//    } else {
//      startDownload();
//    }
}

private void displayFile() {
Bundle bundle = new Bundle();
bundle.putString("filePath", "/storage/emulated/0/uu/HTTP权威指南.pdf");
bundle.putString("tempPath", Environment.getExternalStorageDirectory().getPath());
boolean result = mTbsReaderView.preOpen(parseFormat("HTTP权威指南.pdf"), false);
if (result) {
mTbsReaderView.openFile(bundle);
}
}

private String parseFormat(String fileName) {
return fileName.substring(fileName.lastIndexOf(".") + 1);
}

private String parseName(String url) {
String fileName = null;
try {
fileName = url.substring(url.lastIndexOf("/") + 1);
} finally {
if (TextUtils.isEmpty(fileName)) {
fileName = String.valueOf(System.currentTimeMillis());
}
}
return fileName;
}

private boolean isLocalExist() {
return getLocalFile().exists();
}

private File getLocalFile() {
return new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS), mFileName);
}

private void startDownload() {
mDownloadObserver = new DownloadObserver(new Handler());
getContentResolver().registerContentObserver(Uri.parse("content://downloads/my_downloads"), true, mDownloadObserver);

mDownloadManager = (DownloadManager) getSystemService(DOWNLOAD_SERVICE);
DownloadManager.Request request = new DownloadManager.Request(Uri.parse(mFileUrl));
request.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, mFileName);
request.allowScanningByMediaScanner();
request.setNotificationVisibility(Request.VISIBILITY_HIDDEN);
mRequestId = mDownloadManager.enqueue(request);
}

private void queryDownloadStatus() {
DownloadManager.Query query = new DownloadManager.Query().setFilterById(mRequestId);
Cursor cursor = null;
try {
cursor = mDownloadManager.query(query);
if (cursor != null && cursor.moveToFirst()) {
//已经下载的字节数
int currentBytes = cursor.getInt(cursor.getColumnIndexOrThrow(DownloadManager.COLUMN_BYTES_DOWNLOADED_SO_FAR));
//总需下载的字节数
int totalBytes = cursor.getInt(cursor.getColumnIndexOrThrow(DownloadManager.COLUMN_TOTAL_SIZE_BYTES));
//状态所在的列索引
int status = cursor.getInt(cursor.getColumnIndex(DownloadManager.COLUMN_STATUS));
Log.i("downloadUpdate: ", currentBytes + " " + totalBytes + " " + status);
mDownloadBtn.setText("正在下载：" + currentBytes + "/" + totalBytes);
if (DownloadManager.STATUS_SUCCESSFUL == status && mDownloadBtn.getVisibility() == View.VISIBLE) {
mDownloadBtn.setVisibility(View.GONE);
mDownloadBtn.performClick();
}
}
} finally {
if (cursor != null) {
cursor.close();
}
}
}

@Override
public void onCallBackAction(Integer integer, Object o, Object o1) {

}

@Override
protected void onDestroy() {
super.onDestroy();
mTbsReaderView.onStop();
if (mDownloadObserver != null) {
getContentResolver().unregisterContentObserver(mDownloadObserver);
}
}

private class DownloadObserver extends ContentObserver {

private DownloadObserver(Handler handler) {
super(handler);
}

@Override
public void onChange(boolean selfChange, Uri uri) {
Log.i("downloadUpdate: ", "onChange(boolean selfChange, Uri uri)");
queryDownloadStatus();
}
}
}