我在资产文件夹里有几个文件。我需要把它们都复制到一个文件夹,比如/sdcard/folder。我想从一个线程中做这件事。我该怎么做?
当前回答
由于一些错误,上述解决方案无法工作:
目录创建失败 Android返回的资产也包含三个文件夹:图像,声音和webkit 增加了处理大文件的方法:在项目的资产文件夹中添加扩展名.mp3到文件,在复制目标文件时将没有.mp3扩展名
下面是代码(我留下了Log语句,但你现在可以删除它们):
final static String TARGET_BASE_PATH = "/sdcard/appname/voices/";
private void copyFilesToSdCard() {
copyFileOrDir(""); // copy all files in assets folder in my project
}
private void copyFileOrDir(String path) {
AssetManager assetManager = this.getAssets();
String assets[] = null;
try {
Log.i("tag", "copyFileOrDir() "+path);
assets = assetManager.list(path);
if (assets.length == 0) {
copyFile(path);
} else {
String fullPath = TARGET_BASE_PATH + path;
Log.i("tag", "path="+fullPath);
File dir = new File(fullPath);
if (!dir.exists() && !path.startsWith("images") && !path.startsWith("sounds") && !path.startsWith("webkit"))
if (!dir.mkdirs())
Log.i("tag", "could not create dir "+fullPath);
for (int i = 0; i < assets.length; ++i) {
String p;
if (path.equals(""))
p = "";
else
p = path + "/";
if (!path.startsWith("images") && !path.startsWith("sounds") && !path.startsWith("webkit"))
copyFileOrDir( p + assets[i]);
}
}
} catch (IOException ex) {
Log.e("tag", "I/O Exception", ex);
}
}
private void copyFile(String filename) {
AssetManager assetManager = this.getAssets();
InputStream in = null;
OutputStream out = null;
String newFileName = null;
try {
Log.i("tag", "copyFile() "+filename);
in = assetManager.open(filename);
if (filename.endsWith(".jpg")) // extension was added to avoid compression on APK file
newFileName = TARGET_BASE_PATH + filename.substring(0, filename.length()-4);
else
newFileName = TARGET_BASE_PATH + filename;
out = new FileOutputStream(newFileName);
byte[] buffer = new byte[1024];
int read;
while ((read = in.read(buffer)) != -1) {
out.write(buffer, 0, read);
}
in.close();
in = null;
out.flush();
out.close();
out = null;
} catch (Exception e) {
Log.e("tag", "Exception in copyFile() of "+newFileName);
Log.e("tag", "Exception in copyFile() "+e.toString());
}
}
编辑:更正了一个错位的“;”,这是抛出一个系统的“无法创建目录”错误。
其他回答
你可以用Kotlin在几个步骤中做到这一点,在这里我只复制几个文件,而不是所有从资产到我的应用程序文件目录。
private fun copyRelatedAssets() {
val assets = arrayOf("myhome.html", "support.css", "myscript.js", "style.css")
assets.forEach {
val inputStream = requireContext().assets.open(it)
val nameSplit = it.split(".")
val name = nameSplit[0]
val extension = nameSplit[1]
val path = inputStream.getFilePath(requireContext().filesDir, name, extension)
Log.v(TAG, path)
}
}
这是扩展函数,
fun InputStream.getFilePath(dir: File, name: String, extension: String): String {
val file = File(dir, "$name.$extension")
val outputStream = FileOutputStream(file)
this.copyTo(outputStream, 4096)
return file.absolutePath
}
洛格猫
/data/user/0/com.***.***/files/myhome.html
/data/user/0/com.***.***/files/support.css
/data/user/0/com.***.***/files/myscript.js
/data/user/0/com.***.***/files/style.css
修改了@ danya的SO回答
private void copyAssets(String path, String outPath) {
AssetManager assetManager = this.getAssets();
String assets[];
try {
assets = assetManager.list(path);
if (assets.length == 0) {
copyFile(path, outPath);
} else {
String fullPath = outPath + "/" + path;
File dir = new File(fullPath);
if (!dir.exists())
if (!dir.mkdir()) Log.e(TAG, "No create external directory: " + dir );
for (String asset : assets) {
copyAssets(path + "/" + asset, outPath);
}
}
} catch (IOException ex) {
Log.e(TAG, "I/O Exception", ex);
}
}
private void copyFile(String filename, String outPath) {
AssetManager assetManager = this.getAssets();
InputStream in;
OutputStream out;
try {
in = assetManager.open(filename);
String newFileName = outPath + "/" + filename;
out = new FileOutputStream(newFileName);
byte[] buffer = new byte[1024];
int read;
while ((read = in.read(buffer)) != -1) {
out.write(buffer, 0, read);
}
in.close();
out.flush();
out.close();
} catch (Exception e) {
Log.e(TAG, e.getMessage());
}
}
准备工作
在src /主/资产 添加名称折叠文件夹
使用
File outDir = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS).toString());
copyAssets("fold",outDir.toString());
在外部目录中找到折叠资产内的所有文件和目录
这就是我的个性化文本提取类,希望对大家有用。
package lorenzo.morelli.platedetector;
import android.content.Context;
import android.content.res.AssetManager;
import android.graphics.Bitmap;
import com.googlecode.tesseract.android.TessBaseAPI;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
public class TextExtractor {
private final Context context;
private final String dirName;
private final String language;
public TextExtractor(final Context context, final String dirName, final String language) {
this.context = context;
this.dirName = dirName;
this.language = language;
}
public String extractText(final Bitmap bitmap) {
final TessBaseAPI tessBaseApi = new TessBaseAPI();
final String datapath = this.context.getFilesDir()+ "/tesseract/";
checkFile(new File(datapath + this.dirName + "/"), datapath, this.dirName, this.language);
tessBaseApi.init(datapath, this.language);
tessBaseApi.setImage(bitmap);
final String extractedText = tessBaseApi.getUTF8Text();
tessBaseApi.end();
return extractedText;
}
private void checkFile(final File dir, final String datapath, final String dirName, final String language) {
//directory does not exist, but we can successfully create it
if (!dir.exists()&& dir.mkdirs()) {
copyFiles(datapath, dirName, language);
} //The directory exists, but there is no data file in it
if(dir.exists()) {
final String datafilepath = datapath + "/" + dirName + "/" + language + ".traineddata";
final File datafile = new File(datafilepath);
if (!datafile.exists()) {
copyFiles(datapath, dirName, language);
}
}
}
private void copyFiles(final String datapath, final String dirName, final String language) {
try {
//location we want the file to be at
final String filepath = datapath + "/" + dirName + "/" + language + ".traineddata";
//get access to AssetManager
final AssetManager assetManager = this.context.getAssets();
//open byte streams for reading/writing
final InputStream instream = assetManager.open(dirName + "/" + language + ".traineddata");
final OutputStream outstream = new FileOutputStream(filepath);
//copy the file to the location specified by filepath
byte[] buffer = new byte[1024];
int read;
while ((read = instream.read(buffer)) != -1) {
outstream.write(buffer, 0, read);
}
outstream.flush();
outstream.close();
instream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
要使用它,你需要训练过的数据文件。你可以从这个链接下载trainddata文件。
一旦你下载了你想要的traineddata文件,你需要在你的Android项目中创建一个名为assets的Android资源目录。在新创建的资产文件夹中,你需要创建一个名为“tessdata”的常规目录,在那里你可以放置你的训练数据文件。 最后你必须初始化MainActivity中的“TextExtractor”类。
final TextExtractor textExtractor = new TextExtractor(this, "tessdata", "eng");
第一个参数是上下文,第二个参数是刚刚创建的目录名,最后一个参数是刚刚下载的训练数据的语言。
要提取文本,你必须调用"extractText"方法:
final String text = textExtractor.extractText(imageWithText);
注意,extractText需要一个位图图像才能工作!! 你可以用这一行从你的可绘制文件中创建一个BitMap图像:
final BitMap image = BitmapFactory.decodeResource(getResources(), R.drawable.test_image);
如果你需要更多的支持,我建议你遵循这个有用的指南:https://github.com/SamVanRoy/Android_OCR_App
复制所有文件和目录从资产到您的文件夹!
为了更好地复制,使用apache Commons IO
public void doCopyAssets() throws IOException {
File externalFilesDir = context.getExternalFilesDir(null);
doCopy("", externalFilesDir.getPath());
}
//这是复制的主要方法
private void doCopy(String dirName, String outPath) throws IOException {
String[] srcFiles = assets.list(dirName);//for directory
for (String srcFileName : srcFiles) {
String outFileName = outPath + File.separator + srcFileName;
String inFileName = dirName + File.separator + srcFileName;
if (dirName.equals("")) {// for first time
inFileName = srcFileName;
}
try {
InputStream inputStream = assets.open(inFileName);
copyAndClose(inputStream, new FileOutputStream(outFileName));
} catch (IOException e) {//if directory fails exception
new File(outFileName).mkdir();
doCopy(inFileName, outFileName);
}
}
}
public static void closeQuietly(AutoCloseable autoCloseable) {
try {
if(autoCloseable != null) {
autoCloseable.close();
}
} catch(IOException ioe) {
//skip
}
}
public static void copyAndClose(InputStream input, OutputStream output) throws IOException {
copy(input, output);
closeQuietly(input);
closeQuietly(output);
}
public static void copy(InputStream input, OutputStream output) throws IOException {
byte[] buffer = new byte[1024];
int n = 0;
while(-1 != (n = input.read(buffer))) {
output.write(buffer, 0, n);
}
}
这里是一个针对当前Android设备的清理版本,功能方法设计,以便您可以将其复制到AssetsHelper类,例如;)
/**
*
* Info: prior to Android 2.3, any compressed asset file with an
* uncompressed size of over 1 MB cannot be read from the APK. So this
* should only be used if the device has android 2.3 or later running!
*
* @param c
* @param targetFolder
* e.g. {@link Environment#getExternalStorageDirectory()}
* @throws Exception
*/
@TargetApi(Build.VERSION_CODES.GINGERBREAD)
public static boolean copyAssets(AssetManager assetManager,
File targetFolder) throws Exception {
Log.i(LOG_TAG, "Copying files from assets to folder " + targetFolder);
return copyAssets(assetManager, "", targetFolder);
}
/**
* The files will be copied at the location targetFolder+path so if you
* enter path="abc" and targetfolder="sdcard" the files will be located in
* "sdcard/abc"
*
* @param assetManager
* @param path
* @param targetFolder
* @return
* @throws Exception
*/
public static boolean copyAssets(AssetManager assetManager, String path,
File targetFolder) throws Exception {
Log.i(LOG_TAG, "Copying " + path + " to " + targetFolder);
String sources[] = assetManager.list(path);
if (sources.length == 0) { // its not a folder, so its a file:
copyAssetFileToFolder(assetManager, path, targetFolder);
} else { // its a folder:
if (path.startsWith("images") || path.startsWith("sounds")
|| path.startsWith("webkit")) {
Log.i(LOG_TAG, " > Skipping " + path);
return false;
}
File targetDir = new File(targetFolder, path);
targetDir.mkdirs();
for (String source : sources) {
String fullSourcePath = path.equals("") ? source : (path
+ File.separator + source);
copyAssets(assetManager, fullSourcePath, targetFolder);
}
}
return true;
}
private static void copyAssetFileToFolder(AssetManager assetManager,
String fullAssetPath, File targetBasePath) throws IOException {
InputStream in = assetManager.open(fullAssetPath);
OutputStream out = new FileOutputStream(new File(targetBasePath,
fullAssetPath));
byte[] buffer = new byte[16 * 1024];
int read;
while ((read = in.read(buffer)) != -1) {
out.write(buffer, 0, read);
}
in.close();
out.flush();
out.close();
}
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