在我的資產文件夾中,我有一個名爲lecture.pdf的pdf文件。我試圖將這個文件從資產複製到SD卡,以便從我的應用程序中讀取PDF,但文件無法在SD卡上寫入。有人能告訴我我做錯了什麼。下面是編寫到SD卡目錄代碼將pdf文件從資產複製到SD卡
公共類XAclass延伸活動{
WebView web;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.large);
new Asyntasking();
Intent intent = new Intent(getParent(), MyPdfViewerActivity.class);
intent.putExtra(PdfViewerActivity.EXTRA_PDFFILENAME,
"mnt/sdcard/mylecture/lecture.pdf");
startActivity(intent);
}
private class Asyntasking extends AsyncTask<Void,Void,Void>
{
private void CopyAssets() {
AssetManager assetManager = getAssets();
String[] files = {};
try {
files = assetManager.list("lecture.pdf");
} catch (IOException e) {
Log.e("tag", e.getMessage());
}
for(String filename : files) {
System.out.println("File name => "+filename);
InputStream in= null;
OutputStream out = null;
try {
in = assetManager.open("/mnt/sdcard/mylecture/"+filename); // if files resides inside the "Files" directory itself
out = new FileOutputStream("/mnt/sdcard/mylecture/"+filename);
copyFile(in, out);
in.close();
in = null;
out.flush();
out.close();
out = null;
} catch(Exception e) {
Log.e("tag", e.getMessage());
}
}
}
private void copyFile(InputStream in, OutputStream out) throws IOException {
byte[] buffer = new byte[1024];
int read;
while((read = in.read(buffer)) != -1){
out.write(buffer, 0, read);
}
}
@覆蓋 保護無效doInBackground(虛空...... PARAMS){// TODO自動生成方法存根 CopyAssets(); 返回null; }
}
}
你在manifest文件 添加權限'<使用許可權的android:NAME = 「android.permission.WRITE_EXTERNAL_STORAGE」/>' – Naveen 2013-02-24 07:48:42
同樣的問題我..如果我不使用異步任務比它工作得很好。 – 2013-02-26 14:19:29