android开发 更新下载apk部分机型文件写入失败(Permission denied)

问题：文件写入失败：java.io.FileNotFoundException: /storage/emulated/0/abc.apk: open failed: EACCES (Permission denied)，做自动更新从服务器下载apk存储到手机上，其他两台真机都能存储成功，唯独三星A7100这台不行，权限都加了。

解决：之后参考github的开源项目，再与自己的做了对比，修改整合解决问题。

开源项目：https://github.com/feicien/android-auto-update

修改前代码：

public class UpdateManger {

// 应用程序Contextprivate Context mContext;// 提示消息private String updateMsg = "有最新的软件包，请下载！";// 下载安装包的网络路径private String apkUrl = "http://115.28.6.127:8090/app/1462785029964BirdStore20150929V131.apk";private Dialog noticeDialog;// 提示有软件更新的对话框private Dialog downloadDialog;// 下载对话框private static final String savePath = Environment.getExternalStorageDirectory().getPath()+"/updateDemo/";// 保存apk的文件夹private static final String saveFileName = savePath        + "UpdateDemoRelease.apk";// 进度条与通知UI刷新的handler和msg常量private ProgressBar mProgress;private static final int DOWN_UPDATE = 1;private static final int DOWN_OVER = 2;private static final int DOWN_FAIL = 3;private int progress;// 当前进度private Thread downLoadThread; // 下载线程private boolean interceptFlag = false;// 用户取消下载// 通知处理刷新界面的handlerprivate Handler mHandler = new Handler() {    @SuppressLint("HandlerLeak")    @Override    public void handleMessage(Message msg) {        switch (msg.what) {        case DOWN_UPDATE:            mProgress.setProgress(progress);            break;        case DOWN_OVER:            downloadDialog.cancel();            installApk();            break;        case DOWN_FAIL:            Toast.makeText(mContext, "下载出错", Toast.LENGTH_SHORT).show();            break;         }        super.handleMessage(msg);    }};public UpdateManger(Context context) {    this.mContext = context;}// 显示更新程序对话框，供主程序调用public void checkUpdateInfo() {    showNoticeDialog();}private void showNoticeDialog() {    android.app.AlertDialog.Builder builder = new android.app.AlertDialog.Builder(            mContext);// Builder，可以通过此builder设置改变AleartDialog的默认的主题样式及属性相关信息    builder.setTitle("软件版本更新");    builder.setMessage(updateMsg);    builder.setPositiveButton("下载", new OnClickListener() {        @Override        public void onClick(DialogInterface dialog, int which) {            dialog.dismiss();// 当取消对话框后进行操作一定的代码？取消对话框            showDownloadDialog();        }    });    builder.setNegativeButton("以后再说", new OnClickListener() {        @Override        public void onClick(DialogInterface dialog, int which) {            dialog.dismiss();        }    });    noticeDialog = builder.create();    noticeDialog.setCancelable(false);    noticeDialog.show();}protected void showDownloadDialog() {    android.app.AlertDialog.Builder builder = new android.app.AlertDialog.Builder(            mContext);    builder.setTitle("正在下载");    final LayoutInflater inflater = LayoutInflater.from(mContext);    View v = inflater.inflate(R.layout.progress, null);    mProgress = (ProgressBar) v.findViewById(R.id.progress);    builder.setView(v);// 设置对话框的内容为一个View    builder.setNegativeButton("取消", new OnClickListener() {        @Override        public void onClick(DialogInterface dialog, int which) {            dialog.dismiss();            interceptFlag = true;        }    });    downloadDialog = builder.create();    downloadDialog.show();    downloadApk();}private void downloadApk() {    downLoadThread = new Thread(mdownApkRunnable);    downLoadThread.start();}protected void installApk() {    File apkfile = new File(saveFileName);    if (!apkfile.exists()) {        return;    }    Log.e("File.toString()", ""+apkfile.toString());    Intent i = new Intent(Intent.ACTION_VIEW);    i.setDataAndType(Uri.parse("file://" + apkfile.toString()),            "application/vnd.android.package-archive");// File.toString()会返回路径信息    mContext.startActivity(i);}private Runnable mdownApkRunnable = new Runnable() {    @Override    public void run() {        URL url;        try {            url = new URL(apkUrl);            HttpURLConnection conn = (HttpURLConnection) url                    .openConnection();            conn.connect();            int length = conn.getContentLength();            InputStream ins = conn.getInputStream();            File file = new File(savePath);            if (!file.exists()) {                boolean b = file.mkdirs();                Log.e("exists", saveFileName+","+b);            }            String apkFile = saveFileName;            File ApkFile = new File(apkFile);            FileOutputStream outStream = new FileOutputStream(ApkFile);            int count = 0;            byte buf[] = new byte[1024];            do {                int numread = ins.read(buf);                count += numread;                progress = (int) (((float) count / length) * 100);                // 下载进度                mHandler.sendEmptyMessage(DOWN_UPDATE);                if (numread <= 0) {                    // 下载完成通知安装                    mHandler.sendEmptyMessage(DOWN_OVER);                    break;                }                outStream.write(buf, 0, numread);            } while (!interceptFlag);// 点击取消停止下载            outStream.close();            ins.close();        } catch (Exception e) {            Log.e("Exception", ""+e.getMessage().toString());            mHandler.sendEmptyMessage(DOWN_FAIL);            e.printStackTrace();        }    }};

}

修改后代码：

public class UpdateManger {

// 应用程序Context

private ContextmContext;

// 提示消息

private StringupdateMsg ="有最新的软件包，请下载！";

// 下载安装包的网络路径

private StringapkUrl = "http://115.28.6.127:8090/app/1462785029964BirdStore20150929V131.apk";

private DialognoticeDialog;// 提示有软件更新的对话框

private DialogdownloadDialog;// 下载对话框

private static final String savePath = Environment

.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS)

+ "/updateDemo/";// 保存apk的文件夹

privatestatic final String saveFileName =savePath

+ "UpdateDemoRelease.apk";

// 进度条与通知UI刷新的handler和msg常量

private ProgressBarmProgress;

privatestatic finalint DOWN_UPDATE = 1;

privatestatic finalint DOWN_OVER = 2;

privatestatic finalint DOWN_FAIL = 3;

privateint progress;// 当前进度

private ThreaddownLoadThread; // 下载线程

privateboolean interceptFlag =false;// 用户取消下载

// 通知处理刷新界面的handler

private HandlermHandler = newHandler() {

@SuppressLint("HandlerLeak")

@Override

public void handleMessage(Message msg) {

switch (msg.what) {

caseDOWN_UPDATE:

mProgress.setProgress(progress);

break;

caseDOWN_OVER:

downloadDialog.cancel();

installApk();

break;

caseDOWN_FAIL:

Toast.makeText(mContext,"下载出错", Toast.LENGTH_SHORT).show();

break;

}

super.handleMessage(msg);

}

};

public UpdateManger(Context context) {

this.mContext = context;

}

// 显示更新程序对话框，供主程序调用

public void checkUpdateInfo() {

showNoticeDialog();

}

private void showNoticeDialog() {

android.app.AlertDialog.Builder builder = new android.app.AlertDialog.Builder(

mContext);// Builder，可以通过此builder设置改变AleartDialog的默认的主题样式及属性相关信息

builder.setTitle("软件版本更新");

builder.setMessage(updateMsg);

builder.setPositiveButton("下载",new OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

dialog.dismiss();// 当取消对话框后进行操作一定的代码？取消对话框

showDownloadDialog();

}

});

builder.setNegativeButton("以后再说",new OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

dialog.dismiss();

}

});

noticeDialog = builder.create();

noticeDialog.setCancelable(false);

noticeDialog.show();

}

protectedvoid showDownloadDialog() {

android.app.AlertDialog.Builder builder = new android.app.AlertDialog.Builder(

mContext);

builder.setTitle("正在下载");

final LayoutInflater inflater = LayoutInflater.from(mContext);

View v = inflater.inflate(R.layout.progress,null);

mProgress = (ProgressBar) v.findViewById(R.id.progress);

builder.setView(v);// 设置对话框的内容为一个View

builder.setNegativeButton("取消",new OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

dialog.dismiss();

interceptFlag =true;

}

});

downloadDialog = builder.create();

downloadDialog.show();

downloadApk();

}

private void downloadApk() {

downLoadThread =new Thread(mdownApkRunnable);

downLoadThread.start();

}

protectedvoid installApk() {

File dir = StorageUtils.getCacheDirectory(mContext);

String apkName = apkUrl.substring(apkUrl.lastIndexOf("/") + 1,

apkUrl.length());

File ApkFile = new File(dir, apkName);

if (!ApkFile.exists()) {

return;

}

Log.e("File.toString()","" + ApkFile.toString());

Intent i = new Intent(Intent.ACTION_VIEW);

//如果没有设置SDCard写权限，或者没有sdcard,apk文件保存在内存中，需要授予权限才能安装

String[] command = { "chmod", "777", ApkFile.toString() };

ProcessBuilder builder = new ProcessBuilder(command);

try {

builder.start();

} catch (IOException e) {

e.printStackTrace();

}

i.setDataAndType(Uri.fromFile(ApkFile),

"application/vnd.android.package-archive");// File.toString()会返回路径信息

mContext.startActivity(i);

}

private RunnablemdownApkRunnable = new Runnable() {

@Override

public void run() {

URL url;

try {

url = new URL(apkUrl);

HttpURLConnection conn = (HttpURLConnection) url

.openConnection();

conn.connect();

int length = conn.getContentLength();

InputStream ins = conn.getInputStream();

// File file = new File(savePath);

// if (!file.exists()) {

// boolean b = file.mkdirs();

// Log.e("exists", saveFileName+","+b);

// }

// String apkFile = saveFileName;

// Log.e("exists2", saveFileName);

// File ApkFile = new File(apkFile);

File dir = StorageUtils.getCacheDirectory(mContext);

String apkName = apkUrl.substring(apkUrl.lastIndexOf("/") + 1,

apkUrl.length());

File ApkFile = new File(dir, apkName);

FileOutputStream outStream = new FileOutputStream(ApkFile);

int count = 0;

byte buf[] =new byte[1024];

do {

int numread = ins.read(buf);

count += numread;

progress = (int) (((float) count / length) * 100);

// 下载进度

mHandler.sendEmptyMessage(DOWN_UPDATE);

if (numread <= 0) {

// 下载完成通知安装

mHandler.sendEmptyMessage(DOWN_OVER);

break;

}

outStream.write(buf, 0, numread);

} while (!interceptFlag);// 点击取消停止下载

outStream.close();

ins.close();

} catch (Exception e) {

Log.e("Exception","" + e.getMessage().toString());

mHandler.sendEmptyMessage(DOWN_FAIL);

e.printStackTrace();

}

}

};

}

主要修改两个地方：

一、文件存储路径，这里用了开源项目中的路径创建；

File dir = StorageUtils.getCacheDirectory(mContext);

String apkName = apkUrl.substring(apkUrl.lastIndexOf("/") + 1,

apkUrl.length());

File ApkFile = new File(dir, apkName);

二、授予权限；

//如果没有设置SDCard写权限，或者没有sdcard,apk文件保存在内存中，需要授予权限才能安装

String[] command = {"chmod","777",apkFile.toString()};ProcessBuilder builder = new ProcessBuilder(command);builder.start();