Fileinputstream android 循环无法加载数据 activity 卡住

Question

我的代码似乎在应用程序中循环，因此卡住了。数据成功保存在输出流中没有问题，但我几乎可以肯定 while 循环导致了问题。

这是我的 xml 输入流：

<-------------------- lang-xml ---------- ----->

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/edit_text_2_1"
    android:hint="User name is gonna come here"
    android:textSize="25dp"
    />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/edit_text_2_2"
    android:hint="pass name is gonna come here"
    android:textSize="25dp"
    android:layout_marginTop="25dp"
    />
<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/btn_edit_2_2"
    android:text="load"
    />

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/btn_edit_2_3"
    android:text="Go back"
    />

</LinearLayout>

<------------activity_second.java-------------->

package com.example.admin.file_view;


import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
/**
 * Created by admin on 15-03-2016.
 */
public class activity_second extends Activity{

TextView t1,t2;
Button b1,b2;
String name, pass;

FileInputStream fos=null;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_second);
    t1=(TextView)findViewById(R.id.edit_text_2_1);
    t2=(TextView)findViewById(R.id.edit_text_2_2);
    b1=(Button)findViewById(R.id.btn_edit_2_2);
    b2=(Button)findViewById(R.id.btn_edit_2_3);
    b1.setOnClickListener(new View.OnClickListener() {
        String temp;

        int read=-1;
        @Override
        public void onClick(View v) {
            try {
                fos= openFileInput("haha.txt");
                StringBuffer biffer=new StringBuffer();

                while(fos.read()!=1)
                {
                    biffer.append((char)fos.read());

                }
               // char c=(char)fos.read();
                //Toast.makeText(getApplicationContext(),c+" is getting read",Toast.LENGTH_LONG).show();
        /*        while((read=fos.read())!=-1)
                {
               biffer.append((char)read);
                }*/
                name=biffer.substring(0,biffer.indexOf(" "));
                pass=biffer.substring(biffer.indexOf(" ")+1);
                t1.setText(name);
                t2.setText(pass);

            } catch (FileNotFoundException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    });}}

如果我使用注释部分，我会得到 Index array out of bounds 异常，这很奇怪，也需要帮助.. 如果你需要查看文件输出流：

<----------------MainActivity.java------------>

package com.example.admin.file_view;

import android.app.Activity;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

public class MainActivity extends Activity {

    TextView t1,t2;
    Button b1,b2;
    String name, pass;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        t1=(TextView)findViewById(R.id.edit_txt1);
        t2=(TextView)findViewById(R.id.edit_txt2);
        b1=(Button)findViewById(R.id.btn_edit_1);
        b2=(Button)findViewById(R.id.btn_edit_2);

        b1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                name= t1.getText().toString();
                pass=t2.getText().toString();
                FileOutputStream fos= null;
                try {
                    fos = openFileOutput("haha.txt",MODE_PRIVATE);
                    fos.write(t1.getText().toString().getBytes());
                    fos.write(pass.getBytes());
                } catch (FileNotFoundException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                finally {
                    try {
                        if (fos != null) {
                            fos.close();
                        }
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }

                Toast.makeText(getApplicationContext(),"data saved successfully",Toast.LENGTH_SHORT).show();

            }
        });

        b2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent=new Intent(getApplication(),activity_second.class);
                startActivity(intent);
            }
        });}}

<--------------------output.xml-------->

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.admin.file_view.MainActivity">

<EditText
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/edit_txt1"
    android:hint="Enter the username"
    android:textSize="25dp"
    />

<EditText
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/edit_txt2"
    android:layout_below="@+id/edit_txt1"
    android:hint="Enter pass"
    android:textSize="25dp"
    android:layout_marginTop="25dp"
    />

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@id/edit_txt2"
    android:id="@+id/btn_edit_1"
    android:text="save"
    android:textSize="25dp"
    />

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@id/edit_txt2"
    android:id="@+id/btn_edit_2"
    android:layout_toRightOf="@id/btn_edit_1"
    android:text="nextpage"
    android:textSize="25dp"
    />

</RelativeLayout>


[1]: http://i.stack.imgur.com/bOqgl.png

Answer 1

while(fos.read()!=1)
{
    biffer.append((char)fos.read());
}

这段代码纯属胡说八道。它跳过每个奇数字节。你应该使用 FileReader 和缓冲区。

int count;
char charBuffer = new char[8192];
FileReader reader = new FileReader(...);
while ((count = reader.read(charBuffer)) > 0)
{
    buffer.append(charBuffer, 0, count);
}
reader.close();

Fileinputstream android 循环无法加载数据 activity 卡住

Fileinputstream android looping unable to load data activity stuck

java

android

exception

fileinputstream