在这个项目中，我试图在用户单击删除按钮时将文件从SD卡（例如DICM中的图像）复制到回收文件夹。但是，我面临着问题。我可以删除文件，但无法复制内容。
C.Java - 用于分配目录。
package com.haha.recyclebin;
public class C
{
public static String SDCARD = "/mnt/sdcard";
public static String RECYCLE_BIN_ROOT = SDCARD+"/.Recycle";
}
U.Java - 用于将文件从Sdcard上的一个文件夹复制到回收文件夹。
package com.haha.recyclebin;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
public class U
{
public static void copyFile(File sourceLocation, File targetLocation)
throws FileNotFoundException, IOException
{
U.debug("copying from "+sourceLocation.getAbsolutePath()+" to "+targetLocation.getAbsolutePath());
String destDirPath = targetLocation.getParent();
File destDir = new File(destDirPath);
if(!destDir.exists()){
destDir.mkdirs();
}
InputStream in = new FileInputStream(sourceLocation);
OutputStream out = new FileOutputStream(targetLocation);
// Copy the bits from instream to outstream
byte[] buf = new byte[1024*512];
int len;
while ((len = in.read(buf)) > 0) {
System.out.println("papa");
out.write(buf, 0, len);
System.out.println(">");
}
System.out.println(".");
in.close();
out.close();
}
public static void debug(Object msg){
System.out.println(msg);
}
}
RecycleActivity - 在此代码中使用U.java和C.java： -
package com.haha.recyclebin;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.nio.channels.FileChannel;
import java.util.Set;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.DialogInterface.OnClickListener;
import android.net.Uri;
import android.os.Bundle;
import android.widget.Toast;
public class RecycleActivity extends Activity {
private OnClickListener exitListener = new OnClickListener()
{
@Override
public void onClick(DialogInterface paramDialogInterface, int paramInt)
{
RecycleActivity.this.finish();
}
};
/**
* need a standalone class to hold data (file name)
*/
private final class DeleteFileListener implements OnClickListener
{
String file = null;
/**
* @param file the file to set
*/
public void setFile(String file)
{
this.file = file;
}
@Override
public void onClick(DialogInterface paramDialogInterface, int paramInt)
{
RecycleActivity.this.prepareRecyclebin();
File src = new File(file);
String destPath = C.RECYCLE_BIN_ROOT+file;
File dest = new File(destPath);
try
{
U.copyFile(src, dest); /* using U.java here */
src.delete();
String msg = RecycleActivity.this.getResources().getString(R.string.deleted) + destPath;
Toast.makeText(RecycleActivity.this, msg, Toast.LENGTH_SHORT).show();
} catch (Exception e)
{
e.printStackTrace();
Toast.makeText(RecycleActivity.this, R.string.delete_failed, Toast.LENGTH_SHORT).show();
}
RecycleActivity.this.finish();
}
}
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
Intent intent = getIntent();
debugIntent(intent);
Bundle extras = intent.getExtras();
/* For File Explorer */
Object obj = extras.get(Intent.EXTRA_INTENT);
if(null!=obj){
Intent it2 = (Intent) obj;
Bundle ex2 = it2.getExtras();
Object obj2 = ex2.get(Intent.EXTRA_STREAM);
if(null!=obj2){
Uri uri = (Uri) obj2;
String file = uri.getPath();
System.out.println("file: "+file);
toRecyclebin(file);
}
}
}
/**
* @param file
*/
private void toRecyclebin(String file)
{
if(!file.startsWith(C.SDCARD))
{
promptLimit();
return;
}
String conf = this.getResources().getString(R.string.confirm_delete);
conf+="\n\n"+file;
DeleteFileListener listener = new DeleteFileListener();
listener.setFile(file);
new AlertDialog.Builder(this)
.setMessage(conf)
.setPositiveButton(R.string.yes, listener)
.setNegativeButton(R.string.no, exitListener)
.show();
}
/**
*
*/
private void promptLimit()
{
new AlertDialog.Builder(this)
.setMessage(R.string.limit)
.setPositiveButton(R.string.ok, exitListener)
.show();
}
/**
* @param intent
*/
private void debugIntent(Intent intent)
{
System.out.println("intent: "+intent);
Bundle extras = intent.getExtras();
Set<String> keys = extras.keySet();
for(String key:keys){
Object value = extras.get(key);
System.out.println("-["+key+"]:["+value+"]");
if(value instanceof Intent){
Intent intent2 = (Intent) value;
Bundle ext2 = intent2.getExtras();
Set<String> ks2 = ext2.keySet();
for(String k:ks2){
Object v2 = ext2.get(k);
System.out.println("--["+k+"]:["+v2+"]");
if(v2 instanceof Intent){
Intent i3 = (Intent) v2;
Bundle e3 = i3.getExtras();
Set<String> ks3 = e3.keySet();
for(String kk:ks3){
Object v3 = e3.get(kk);
System.out.println("---["+kk+"]:["+v3+"]");
}
}
}
}
}
Uri data = intent.getData();
System.out.println("data: "+data);
}
void prepareRecyclebin(){
File root = new File(C.RECYCLE_BIN_ROOT);
if(!root.exists()){
root.mkdirs();
}
}
}
我有文件浏览器工作正常，我可以在SD卡上看到图像和音乐，我也可以删除。但删除后，他们应该转到Recycle文件夹（如C.java中所述）。我在eclipse中使用文件浏览器手动创建了回收文件夹（/ mnt / sdcard / Recycle）。
但是我没有看到回收文件夹中的文件。
守则有问题吗？
任何形式的帮助都将受到赞赏。
谢谢！
答案 0 :(得分：2)
您是否已调试并确保已执行copyfile？
这是我的CopyFile函数，它们完全相同：
public static boolean copyFile(String from, String to) {
try {
int bytesum = 0;
int byteread = 0;
File oldfile = new File(from);
if (oldfile.exists()) {
InputStream inStream = new FileInputStream(from);
FileOutputStream fs = new FileOutputStream(to);
byte[] buffer = new byte[1444];
while ((byteread = inStream.read(buffer)) != -1) {
bytesum += byteread;
fs.write(buffer, 0, byteread);
}
inStream.close();
fs.close();
}
return true;
} catch (Exception e) {
return false;
}
}
答案 1 :(得分：0)
尝试使用以下代码，它会起作用。
public void Save_To_Phone(Bitmap bitmap){
try {
FileOutputStream os = new FileOutputStream(YourSDCardPath);
bitmap.compress(CompressFormat.JPEG, 80, os);
os.close();
} catch (Exception e) {
Log.w("ExternalStorage", "Error writing file", e);
}
}