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我构建了一个示例应用程序，它从用户那里获取输入并保存在我的应用程序资产文件夹中的文本文件“示例”中。

这是我的 MainActivity.java，

 package com.example.sampledatabaseapp;

 import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStreamWriter;
 import android.os.Bundle;
 import android.app.Activity;
 import android.content.Context;
 import android.content.res.AssetManager;
 import android.text.Editable;
 import android.view.Menu;
 import android.view.View;
 import android.widget.Button;
 import android.widget.EditText;
 import android.widget.Toast;

  public class MainActivity extends Activity {

protected static final android.content.Context Context = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    Button btn=(Button)findViewById(R.id.button1);
    btn.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {

            EditText txtname=(EditText)findViewById(R.id.editText1);    
            String name=txtname.getText().toString();

             AssetManager am=Context.getAssets();
            try {

                InputStream is=am.open("sample");
                OutputStreamWriter out=new OutputStreamWriter(openFileOutput("sample",MODE_APPEND));
                out.write(name);

                out.close();
                Toast.makeText(Context,"Text Saved !",Toast.LENGTH_LONG).show();

            } catch (IOException e) {

                e.printStackTrace();
                Toast.makeText(Context,"Sorry Text could't be added",Toast.LENGTH_LONG).show();
            }


        }
    });
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.activity_main, menu);
    return true;
}

 }

我的activity_main.xml，

<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"
tools:context=".MainActivity" >

<EditText
    android:id="@+id/editText1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentTop="true"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="46dp"
    android:ems="10" 
    android:hint="@string/Enter_Name">

    <requestFocus />
</EditText>

<Button
    android:id="@+id/button1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignLeft="@+id/editText1"
    android:layout_alignRight="@+id/editText1"
    android:layout_below="@+id/editText1"
    android:layout_marginTop="82dp"
    android:text="@string/Save" />

</RelativeLayout>

我开始逐行调试，当调试器调试“AssetManager am=Context.getAssets();”行时 在我的 MainActivity.java 文件中，它显示“找不到 ZygoteInit$MethodAndArgsCaller.run() 的源”。我下载了源代码并附上了。

但是，我仍然不知道我哪里出错了。这是我的堆栈跟踪，

  12-27 13:32:16.467: D/InputEventConsistencyVerifier(1803): KeyEvent: ACTION_UP but key was not down.
  12-27 13:32:16.467: D/InputEventConsistencyVerifier(1803):   in  android.widget.Button{40d02568 VFED..C. .F....I. 135,168-345,216 #7f070001 app:id/button1}
  12-27 13:32:16.467: D/InputEventConsistencyVerifier(1803):   0: sent at  5236119000000, KeyEvent { action=ACTION_UP, keyCode=KEYCODE_TAB, scanCode=15, metaState=0, flags=0x8, repeatCount=0, eventTime=5236119, downTime=5235983, deviceId=0, source=0x101 }

  12-27 13:32:16.908: W/Trace(1803): Unexpected value from nativeGetEnabledTags: 0
  12-27 13:32:16.938: W/Trace(1803): Unexpected value from nativeGetEnabledTags: 0
  12-27 13:32:16.969: W/Trace(1803): Unexpected value from nativeGetEnabledTags: 0
  12-27 13:32:16.969: W/Trace(1803): Unexpected value from nativeGetEnabledTags: 0
  12-27 13:32:17.008: W/Trace(1803): Unexpected value from nativeGetEnabledTags: 0
  12-27 13:32:17.038: W/Trace(1803): Unexpected value from nativeGetEnabledTags: 0
  12-27 13:32:17.118: W/Trace(1803): Unexpected value from nativeGetEnabledTags: 0
  12-27 13:32:17.148: W/Trace(1803): Unexpected value from nativeGetEnabledTags: 0

我不知道我是否使用正确的方法将文本写入 android 中的文本文件。如果有错请指教。

请任何人帮助！

谢谢。

4

1 回答 1

1

MODE_APPEND 当然是将数据附加到现有文件中。如果你想创建一个新的，你应该使用 MODE_PRIVATE

OutputStreamWriter out=new OutputStreamWriter(openFileOutput("sample",MODE_PRIVATE));

当你阅读文件时，

        try {
            FileInputStream fileInputStream;
            fileInputStream = openFileInput("sample");
            byte[] readBytes = new byte[fileInputStream.available()];
            fileInputStream.read(readBytes);
            String readString = new String(readBytes);
            Log.v("readString", readString);
            fileInputStream.close();
        } catch (FileNotFoundException e) {
        } catch (IOException e) {
        }

好的，删除这一行怎么样？

AssetManager am=Context.getAssets();

您不必使用 AssetManager。

然后你用写这个。

try {
            FileOutputStream fileOutputStream = openFileOutput("myfile.txt", MODE_PRIVATE);
            String writeString = "test";
            fileOutputStream.write(writeString.getBytes());
        } catch (FileNotFoundException e) {
        } catch (IOException e) {
        }
于 2013-03-05T04:25:53.207 回答