在android中创建文本文件并保存数据
我对android应用程序编程还不熟悉 在下面的代码中,我想通过一些EditText从用户那里获取输入,然后将它们保存到一个文件中。我使用android studio,在输入之后,我检查了文件,它总是空的。我试图显示内容,但仍然没有得到任何输出。代码有什么问题 请帮帮我在android中创建文本文件并保存数据,android,file,Android,File,我对android应用程序编程还不熟悉 在下面的代码中,我想通过一些EditText从用户那里获取输入,然后将它们保存到一个文件中。我使用android studio,在输入之后,我检查了文件,它总是空的。我试图显示内容,但仍然没有得到任何输出。代码有什么问题 请帮帮我 public class user extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onC
public class user extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_user);
nextClick();
}
public void nextClick()
{
final Context context = this;
Button next =(Button) findViewById(R.id.userNext);
next.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
try {
EditText e1 = (EditText) findViewById(R.id.name);
EditText e2 = (EditText) findViewById(R.id.designation);
EditText e3 = (EditText) findViewById(R.id.orgname);
EditText e4 = (EditText) findViewById(R.id.address);
EditText e5 = (EditText) findViewById(R.id.city);
EditText e6 = (EditText) findViewById(R.id.state);
EditText e7 = (EditText) findViewById(R.id.zip);
FileOutputStream fos = openFileOutput("data.txt", Context.MODE_WORLD_WRITEABLE);
OutputStreamWriter osw = new OutputStreamWriter(fos);
osw.write(e1.toString());
fos.flush();
fos.close();
}
catch(Exception e) {
}
try
{
FileInputStream fis = new FileInputStream("data.txt");
while(fis.read()!=-1)
{
System.out.println((char)fis.read());
}
}
catch(Exception e)
{
}
Intent intent3 = new Intent(context,com.example.cheruvu.rs.user2.class);
startActivity(intent3);
}
});
}
}
写入文件时,需要从EditText字段getText(),如下所示
osw.write(e1.getText().toString())代码>这个怎么办。这将在手机上创建文件(不是SD卡)
试着用这个替换你的代码,看看它是否有效
public class user extends Activity {
EditText e1;
EditText e2;
EditText e3;
EditText e4;
EditText e5;
EditText e6;
EditText e7;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_user);
e1 = (EditText) findViewById(R.id.name);
e2 = (EditText) findViewById(R.id.designation);
e3 = (EditText) findViewById(R.id.orgname);
e4 = (EditText) findViewById(R.id.address);
e5 = (EditText) findViewById(R.id.city);
e6 = (EditText) findViewById(R.id.state);
e7 = (EditText) findViewById(R.id.zip);
nextClick();
}
public void nextClick()
{
final Context context = this;
Button next =(Button) findViewById(R.id.userNext);
next.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
try {
FileOutputStream fos = openFileOutput("data.txt", Context.MODE_WORLD_WRITEABLE);
OutputStreamWriter osw = new OutputStreamWriter(fos);
osw.write(e1.getText().toString());
fos.flush();
fos.close();
}
catch(Exception e) {
}
try
{
FileInputStream fis = new FileInputStream("data.txt");
while(fis.read()!=-1)
{
System.out.println((char)fis.read());
}
}
catch(Exception e)
{
}
Intent intent3 = new Intent(context,com.example.cheruvu.rs.user2.class);
startActivity(intent3);
}
});
}
}
为简单起见,我试图仅从您在清单中声明的写入外部存储权限的一个edittextshave中获取输入,但我想将其存储在内存中?仍然无法工作:(catch(Exception e){}
don't do that.oops!很抱歉。我现在包括了这一点,并得到以下信息:正在停止未恢复的活动:{com.example.cheruvu.rs/com.example.cheruvu.rs.user}java.lang.RuntimeException:正在停止未恢复的活动:{com.example.cheruvu.rs/com.example.cheruvu.rs.user}位于android.app.ActivityThread.performStopActivityInner(ActivityThread.java:3396)位于android.app.ActivityThread.HandleTopActivity(ActivityThread.java:3477)位于……….如何处理这些异常?不起作用:(实际上,我在res目录中创建了文件,然后添加了代码。现在,我按照您所说的那样尝试了,但仍然不起作用。请尝试getAbsolutePath()而不是getAbsoluteFile(),因为我在res目录中找不到该文件,您能告诉我该文件是在哪里创建的吗?无论如何,仍然没有得到输出:(它是在您手机的根文件夹中创建的。My Files->All Files->Device storageok,因此无法访问该文件?但我希望完全访问该文件,以便以后可以从该文件中导出数据。我可以这样做吗?不工作……我快发疯了,无法理解该代码的错误,因为我的代码中没有任何内容:(您是否尝试使用其他模式?如上下文.mode\u PRIVATE
?
public class user extends Activity {
EditText e1;
EditText e2;
EditText e3;
EditText e4;
EditText e5;
EditText e6;
EditText e7;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_user);
e1 = (EditText) findViewById(R.id.name);
e2 = (EditText) findViewById(R.id.designation);
e3 = (EditText) findViewById(R.id.orgname);
e4 = (EditText) findViewById(R.id.address);
e5 = (EditText) findViewById(R.id.city);
e6 = (EditText) findViewById(R.id.state);
e7 = (EditText) findViewById(R.id.zip);
nextClick();
}
public void nextClick()
{
final Context context = this;
Button next =(Button) findViewById(R.id.userNext);
next.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
try {
FileOutputStream fos = openFileOutput("data.txt", Context.MODE_WORLD_WRITEABLE);
OutputStreamWriter osw = new OutputStreamWriter(fos);
osw.write(e1.getText().toString());
fos.flush();
fos.close();
}
catch(Exception e) {
}
try
{
FileInputStream fis = new FileInputStream("data.txt");
while(fis.read()!=-1)
{
System.out.println((char)fis.read());
}
}
catch(Exception e)
{
}
Intent intent3 = new Intent(context,com.example.cheruvu.rs.user2.class);
startActivity(intent3);
}
});
}
}