我正在尝试创建一个简单的Android应用程序,它可以保存EditText表单中的文本并将其存储在内部存储器中。一切似乎工作正常(出现“已保存”消息),除非我退出活动并重新启动它,文件中保存的文本根本不加载。我在这里错过了什么吗?
public class ModifyInfo extends Activity{
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.edit);
Bundle extras = getIntent().getExtras();
if(extras != null){
int dayNum = extras.getInt("day");
String dayName = "";
switch(dayNum){
case 1:
dayName = this.getString(R.string.dayMon);
break;
case 2:
dayName = this.getString(R.string.dayTue);
break;
case 3:
dayName = this.getString(R.string.dayWed);
break;
case 4:
dayName = this.getString(R.string.dayThu);
break;
case 5:
dayName = this.getString(R.string.dayFri);
break;
case 6:
dayName = this.getString(R.string.daySat);
break;
default:
dayName = this.getString(R.string.daySun);
break;
}
final TextView dayText = (TextView) findViewById(R.id.dayName);
final TextView editData = (TextView) findViewById(R.id.editData);
final Button save = (Button) findViewById(R.id.buttonSave);
final Button clear = (Button) findViewById(R.id.buttonClear);
final String Day = dayName;
dayText.setText(dayName);
clear.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
editData.setText("");
}
});
save.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
String FILEOUTPUT = Day + ".txt";
try {
String string = editData.getText().toString();
FileOutputStream fos = openFileOutput(FILEOUTPUT, Context.MODE_PRIVATE);
fos.write(string.getBytes());
fos.close();
Toast.makeText(ModifyInfo.this, "Saved", Toast.LENGTH_SHORT).show();
} catch (IOException e) {
Toast.makeText(ModifyInfo.this, "Save error", Toast.LENGTH_SHORT).show();
}
}
});
File FILEINPUT = new File(Day + ".txt");
try {
BufferedReader bfr = new BufferedReader(new FileReader(FILEINPUT));
String line;
while ((line = bfr.readLine()) != null)
{
editData.setText(line);
}
bfr.close();
} catch (Exception e) {
editData.setText("");
}
}
}
}
答案 0 :(得分:1)
您可能正在从文件的最后一行读取\ n或此类空格,因为您正在调用editData.setText(line); ,将文本重置为当前行。 或者您也可能遇到异常,在这种情况下,您通过清除editText来处理该异常。
应该是这样的:
try {
BufferedReader bfr = new BufferedReader(new FileReader(FILEINPUT));
String line;
String fullText = "";
while ((line = bfr.readLine()) != null)
{
fullText += line;
}
bfr.close();
editData.setText(fullText);
} catch (Exception e) {
editData.setText("");
}
根据您的说明,您应检查是否按照以下所述正确打开文件:http://developer.android.com/guide/topics/data/data-storage.html#filesInternal
从内部存储中读取文件:
1. Call openFileInput() and pass it the name of the file to read. This returns a FileInputStream.
2. Read bytes from the file with read().
3. Then close the stream with close().
您正尝试使用BufferedReader打开。
答案 1 :(得分:0)
android可能会锁定某些文件夹中的文件而您无法修改它们。您可以使用共享首选项或静态对象。