我想设置按钮点击事件备份SD卡上的应用程序数据。 这是我的代码:
shv.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
Toast.makeText(SecondActivity.this, "backup Button press",Toast.LENGTH_LONG).show();
boolean rc = MyDatabaseTools.backup();
System.out.println(rc);
if(rc==true)
{
Toast.makeText(SecondActivity.this, "backup Successfully",Toast.LENGTH_LONG).show();
}
else
{
Toast.makeText(SecondActivity.this, "backup error",Toast.LENGTH_LONG).show();
}
}
});
我这样做:
public class MyDatabaseTools {
private String appName = "";
private String packageName = "";
public static boolean backup() {
boolean rc = false;
boolean writeable = isSDCardWriteable();
if (writeable) {
File file = new File(Environment.getDataDirectory() + "/data/<com.example.judgedetail>/databases/ado.db");
File fileBackupDir = new File(Environment.getExternalStorageDirectory(), "ADOBOOK" + "/backup");
if (!fileBackupDir.exists()) {
fileBackupDir.mkdirs();
}
if (file.exists()) {
File fileBackup = new File(fileBackupDir, "ado.db");
try {
fileBackup.createNewFile();
/*Files.copyFile(file, fileBackup);*/ //got error here dis line not work
rc = true;
} catch (IOException ioException) {
//
} catch (Exception exception) {
//
}
}
}
return rc;
}
private static boolean isSDCardWriteable() {
boolean rc = false;
String state = Environment.getExternalStorageState();
if (Environment.MEDIA_MOUNTED.equals(state)) {
rc = true;
}
return rc;
}
public MyDatabaseTools(final Context context, final String appName) {
this.appName = appName;
packageName = context.getPackageName();
}
}
Files.copyFile(file,fileBackup); 这条线出错了。 我该如何解决这个问题? 请帮忙。
答案 0 :(得分:0)
试试这个:
public void writeToSD() throws IOException {
File f=new File("/data/data/com.YourPackageName/databases/DBName");
FileInputStream fis=null;
FileOutputStream fos=null;
try{
fis=new FileInputStream(f);
fos=new FileOutputStream("/mnt/sdcard/dump.db");
while(true){
int i=fis.read();
if(i!=-1){
fos.write(i);
}
else{
break;
}
}
fos.flush();
}
catch(Exception e){
e.printStackTrace();
}
finally{
try{
fos.close();
fis.close();
}
catch(IOException ioe){
System.out.println(ioe);
}
}
}
答案 1 :(得分:0)
我不知道你从哪里复制了这些代码,但是你或者海报错过了什么。 Files.copyFile()
不存在Android API函数,我想这就是您所描述的行不起作用。
你必须使用其他方法复制你的文件,我建议像这样: