Android 为什么我会遇到FileNotFoundException?我可以在这个位置看到文件,所以我知道它存在

Android 为什么我会遇到FileNotFoundException?我可以在这个位置看到文件,所以我知道它存在,android,file,alert,filenotfoundexception,Android,File,Alert,Filenotfoundexception,我有一个长ClickListener的文件列表,它会弹出一个带有删除和重命名选项的上下文菜单。它们启动deleteDialog()或renameDialog()。这些函数调用delete()或rename()。删除有效,但重命名将提供: 05-05 10:26:44.105: W/System.err(19017884): java.io.FileNotFoundException: Failed to rename file: /sdcard/My Webs/new/index.php 我甚

我有一个长ClickListener的文件列表,它会弹出一个带有删除和重命名选项的上下文菜单。它们启动deleteDialog()或renameDialog()。这些函数调用delete()或rename()。删除有效,但重命名将提供:

05-05 10:26:44.105: W/System.err(19017884): java.io.FileNotFoundException: Failed to rename file: /sdcard/My Webs/new/index.php
我甚至认为我可以在文件系统的这个位置看到这个文件

以下是我的警报代码:

void delete(File f) throws IOException {
    if (f.isDirectory()) {
        for (File c : f.listFiles())
            delete(c);
    }
    if (!f.delete())
        throw new FileNotFoundException("Failed to delete file: " + f);
}

void rename(File f, String newName) throws IOException {
    File newFile = new File(newName);

    f.renameTo(newFile);

    if (!f.renameTo(newFile))
        throw new FileNotFoundException("Failed to rename file: " + f);
}

public void delDialog(int position) {
    final int pos = position;

    final AlertDialog alertDialog = new AlertDialog.Builder(this).create();
    alertDialog.setIcon(R.drawable.remove);
    alertDialog.setTitle(getString(R.string.delete));

    alertDialog.setButton("Delete", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int which) {

            String selectedFileString = directoryEntries.get(pos).getText();
            File tmpFile = new File(currentDirectory.toString()
                    + selectedFileString);

            try {
                delete(tmpFile);
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            directoryEntries.remove(pos);
            itla.notifyDataSetChanged();

            currentFile = null;
            changed = false;
            return;
        }

    });
    alertDialog.setButton2("Cancel", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int which) {
            alertDialog.dismiss();
        }
    });

    alertDialog.setMessage("Are you sure you want to delete this file?");
    alertDialog.show();
}

public void renameDialog(int position) {
    final int pos = position;

    final AlertDialog alertDialog = new AlertDialog.Builder(this).create();
    alertDialog.setIcon(R.drawable.renameicon);
    alertDialog.setTitle(getString(R.string.rename));

    alertDialog.setButton("Rename", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int which) {

            String selectedFileString = directoryEntries.get(pos).getText();
            File tmpFile = new File(currentDirectory.toString()
                    + selectedFileString);

            try {
                rename(tmpFile, "test.html");
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            itla.notifyDataSetChanged();

            return;
        }

    });
    alertDialog.setButton2("Cancel", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int which) {
            alertDialog.dismiss();
        }
    });

    alertDialog.setMessage("Are you sure you want to rename this file?");
    alertDialog.show();
}

public void Show_Context(Context context, String message, int position) {
    final AlertDialog customDialog = new AlertDialog.Builder(this).create();
    LayoutInflater layoutInflater = (LayoutInflater) getApplicationContext()
            .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    View view = layoutInflater.inflate(R.layout.contextmenu, null);
    final Button del = (Button) view.findViewById(R.id.delBtn);
    final Button rename = (Button) view.findViewById(R.id.renameBtn);
    final int pos = position;
    customDialog.setView(del);
    customDialog.setView(rename);

    del.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            customDialog.dismiss();
            delDialog(pos);
        }
    });

    rename.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            customDialog.dismiss();
            renameDialog(pos);
        }
    });

    customDialog.setView(view);
    customDialog.show();

}

正如您所看到的,deleteDialog()和renameDialog()的代码是相同的,但renameDialog()抛出FileNotFoundException

您是否尝试过完全限定目标的文件名?您当前正试图从currentDirectory.toString()+selectedFileString重命名为“test.html”

您可能想尝试currentDirectory.toString()+“test.html”,否则可能会遇到权限问题。

您调用了两次
f.renameTo(newFile)
!正常情况下一次,在
if()
条件下第二次。我猜第一次它已经被重命名了,所以当你第二次这样做时,它失败了(要么因为文件不再有相同的名称,要么因为它已经有了新的文件名)

尝试删除第一个
.f.重命名()


还要注意,返回false可能有各种原因,不仅仅是找不到文件。当然,您会得到FileNotFoundException,因为您自己在代码中抛出它:-)

您在清单文件中添加了这一行吗<代码>
f.renameTo(newFile);

if (!f.renameTo(newFile)) {...}