I am new to Android development.
我是Android开发的新手。
I need to read a text file from the SD card and display that text file. Is there any way to view a text file directly in Android or else how can I read and display the contents of a text file?
我需要从SD卡读取文本文件并显示该文本文件。有没有办法直接在Android中查看文本文件,或者我如何阅读和显示文本文件的内容?
5 个解决方案
#1
118
In your layout you'll need something to display the text. A TextView
is the obvious choice. So you'll have something like this:
在您的布局中,您需要一些东西来显示文本。 TextView是显而易见的选择。所以你会有这样的事情:
<TextView
android:id="@+id/text_view"
android:layout_width="fill_parent"
android:layout_height="fill_parent"/>
And your code will look like this:
你的代码看起来像这样:
//Find the directory for the SD Card using the API
//*Don't* hardcode "/sdcard"
File sdcard = Environment.getExternalStorageDirectory();
//Get the text file
File file = new File(sdcard,"file.txt");
//Read text from file
StringBuilder text = new StringBuilder();
try {
BufferedReader br = new BufferedReader(new FileReader(file));
String line;
while ((line = br.readLine()) != null) {
text.append(line);
text.append('\n');
}
br.close();
}
catch (IOException e) {
//You'll need to add proper error handling here
}
//Find the view by its id
TextView tv = (TextView)findViewById(R.id.text_view);
//Set the text
tv.setText(text);
This could go in the onCreate()
method of your Activity
, or somewhere else depending on just what it is you want to do.
这可以放在Activity的onCreate()方法中,也可以放在其他地方,具体取决于你想要做什么。
#2
6
In response to
回应
Don't hardcode /sdcard/
不要硬编码/ SD卡/
Sometimes we HAVE TO hardcode it as in some phone models the API method returns the internal phone memory.
有时我们必须对其进行硬编码,因为在某些手机型号中,API方法会返回内部手机内存。
Known types: HTC One X and Samsung S3.
已知类型:HTC One X和三星S3。
Environment.getExternalStorageDirectory().getAbsolutePath() gives a different path - Android
Environment.getExternalStorageDirectory()。getAbsolutePath()给出了一个不同的路径--Android
#3
1
BufferedReader br = null;
try {
String fpath = Environment.getExternalStorageDirectory() + <your file name>;
try {
br = new BufferedReader(new FileReader(fpath));
} catch (FileNotFoundException e1) {
e1.printStackTrace();
}
String line = "";
while ((line = br.readLine()) != null) {
//Do something here
}
#4
0
package com.example.readfilefromexternalresource;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import android.app.Activity;
import android.app.ActionBar;
import android.app.Fragment;
import android.os.Bundle;
import android.os.Environment;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import android.widget.Toast;
import android.os.Build;
public class MainActivity extends Activity {
private TextView textView;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
textView = (TextView)findViewById(R.id.textView);
String state = Environment.getExternalStorageState();
if (!(state.equals(Environment.MEDIA_MOUNTED))) {
Toast.makeText(this, "There is no any sd card", Toast.LENGTH_LONG).show();
} else {
BufferedReader reader = null;
try {
Toast.makeText(this, "Sd card available", Toast.LENGTH_LONG).show();
File file = Environment.getExternalStorageDirectory();
File textFile = new File(file.getAbsolutePath()+File.separator + "chapter.xml");
reader = new BufferedReader(new FileReader(textFile));
StringBuilder textBuilder = new StringBuilder();
String line;
while((line = reader.readLine()) != null) {
textBuilder.append(line);
textBuilder.append("\n");
}
textView.setText(textBuilder);
} catch (FileNotFoundException e) {
// TODO: handle exception
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
finally{
if(reader != null){
try {
reader.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
}
}
#5
0
Beware: some phones have 2 sdcards , an internal fixed one and a removable card. You can find the name of the last one via a standard app:"Mijn Bestanden" ( in English: "MyFiles" ? ) When I open this app (item:all files) the path of the open folder is "/sdcard" ,scrolling down there is an entry "external-sd" , clicking this opens the folder "/sdcard/external_sd/" . Suppose I want to open a text-file "MyBooks.txt" I would use something as :
请注意:有些手机有2个sdcards,一个内置固定卡和一个可移动卡。您可以通过标准应用找到最后一个的名称:“Mijn Bestanden”(英文:“MyFiles”?)当我打开这个应用程序(项目:所有文件)时,打开文件夹的路径是“/ sdcard”,向下滚动有一个条目“external-sd”,单击此按钮将打开文件夹“/ sdcard / external_sd /”。假设我想打开一个文本文件“MyBooks.txt”我会用以下内容:
String Filename = "/mnt/sdcard/external_sd/MyBooks.txt" ;
File file = new File(fname);...etc...
#1
118
In your layout you'll need something to display the text. A TextView
is the obvious choice. So you'll have something like this:
在您的布局中,您需要一些东西来显示文本。 TextView是显而易见的选择。所以你会有这样的事情:
<TextView
android:id="@+id/text_view"
android:layout_width="fill_parent"
android:layout_height="fill_parent"/>
And your code will look like this:
你的代码看起来像这样:
//Find the directory for the SD Card using the API
//*Don't* hardcode "/sdcard"
File sdcard = Environment.getExternalStorageDirectory();
//Get the text file
File file = new File(sdcard,"file.txt");
//Read text from file
StringBuilder text = new StringBuilder();
try {
BufferedReader br = new BufferedReader(new FileReader(file));
String line;
while ((line = br.readLine()) != null) {
text.append(line);
text.append('\n');
}
br.close();
}
catch (IOException e) {
//You'll need to add proper error handling here
}
//Find the view by its id
TextView tv = (TextView)findViewById(R.id.text_view);
//Set the text
tv.setText(text);
This could go in the onCreate()
method of your Activity
, or somewhere else depending on just what it is you want to do.
这可以放在Activity的onCreate()方法中,也可以放在其他地方,具体取决于你想要做什么。
#2
6
In response to
回应
Don't hardcode /sdcard/
不要硬编码/ SD卡/
Sometimes we HAVE TO hardcode it as in some phone models the API method returns the internal phone memory.
有时我们必须对其进行硬编码,因为在某些手机型号中,API方法会返回内部手机内存。
Known types: HTC One X and Samsung S3.
已知类型:HTC One X和三星S3。
Environment.getExternalStorageDirectory().getAbsolutePath() gives a different path - Android
Environment.getExternalStorageDirectory()。getAbsolutePath()给出了一个不同的路径--Android
#3
1
BufferedReader br = null;
try {
String fpath = Environment.getExternalStorageDirectory() + <your file name>;
try {
br = new BufferedReader(new FileReader(fpath));
} catch (FileNotFoundException e1) {
e1.printStackTrace();
}
String line = "";
while ((line = br.readLine()) != null) {
//Do something here
}
#4
0
package com.example.readfilefromexternalresource;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import android.app.Activity;
import android.app.ActionBar;
import android.app.Fragment;
import android.os.Bundle;
import android.os.Environment;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import android.widget.Toast;
import android.os.Build;
public class MainActivity extends Activity {
private TextView textView;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
textView = (TextView)findViewById(R.id.textView);
String state = Environment.getExternalStorageState();
if (!(state.equals(Environment.MEDIA_MOUNTED))) {
Toast.makeText(this, "There is no any sd card", Toast.LENGTH_LONG).show();
} else {
BufferedReader reader = null;
try {
Toast.makeText(this, "Sd card available", Toast.LENGTH_LONG).show();
File file = Environment.getExternalStorageDirectory();
File textFile = new File(file.getAbsolutePath()+File.separator + "chapter.xml");
reader = new BufferedReader(new FileReader(textFile));
StringBuilder textBuilder = new StringBuilder();
String line;
while((line = reader.readLine()) != null) {
textBuilder.append(line);
textBuilder.append("\n");
}
textView.setText(textBuilder);
} catch (FileNotFoundException e) {
// TODO: handle exception
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
finally{
if(reader != null){
try {
reader.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
}
}
#5
0
Beware: some phones have 2 sdcards , an internal fixed one and a removable card. You can find the name of the last one via a standard app:"Mijn Bestanden" ( in English: "MyFiles" ? ) When I open this app (item:all files) the path of the open folder is "/sdcard" ,scrolling down there is an entry "external-sd" , clicking this opens the folder "/sdcard/external_sd/" . Suppose I want to open a text-file "MyBooks.txt" I would use something as :
请注意:有些手机有2个sdcards,一个内置固定卡和一个可移动卡。您可以通过标准应用找到最后一个的名称:“Mijn Bestanden”(英文:“MyFiles”?)当我打开这个应用程序(项目:所有文件)时,打开文件夹的路径是“/ sdcard”,向下滚动有一个条目“external-sd”,单击此按钮将打开文件夹“/ sdcard / external_sd /”。假设我想打开一个文本文件“MyBooks.txt”我会用以下内容:
String Filename = "/mnt/sdcard/external_sd/MyBooks.txt" ;
File file = new File(fname);...etc...