您好，我正在尝试从 Android 设备上的文件中逐行打印包含双数据的文本文件，但它似乎不起作用，出了什么问题？我没有收到任何错误，但无法正确打印？
在我的 bodyTempInfo View 中我得到读数:
Your Body Temperature Readings are:[]
我的temp2.txt文件，一共有1440个数字，这里就不全部粘贴了
37.06750839
36.89390613
36.88484785
36.81941363
36.81815453
36.97372599
37.0510889
36.90421803
36.90452867
36.81245808
36.91739551
37.05989195
36.80757783
36.85141347
37.04927826
36.80384926
36.94000689
37.04948705
37.07007973
36.95211596
37.05161886
36.97029703
37.03218835
36.89381629
我的bodyTempInfo.Java
package com.teamfara.circadianrhythmmonitor4;
import android.os.Bundle;
import android.os.Environment;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.widget.TextView;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
public class bodyTempInfo extends AppCompatActivity {
ArrayList<Double> currentBodyTemp;
public void displayCurrentBodyTempArray(View view) throws FileNotFoundException {
ArrayList<Double> list = new ArrayList<>();
File sdcard = Environment.getExternalStorageDirectory();
//Get the text file
//Read text from file
File file = new File(sdcard, "temp2.txt");
StringBuilder text = new StringBuilder();
try {
BufferedReader br = new BufferedReader(new FileReader(file));
String line;
while ((line = br.readLine()) != null) {
text.append(line);
list.add(Double.parseDouble(line));
text.append('\n');
}
br.close();
}
catch(IOException e) {
}
/*
Scanner file2 = new Scanner(new File(sdcard, "temp.txt"));
while (file2.hasNextLine()) {
String line = file2.nextLine();
Scanner scanner = new Scanner(line);
scanner.useDelimiter(",");
while (scanner.hasNextDouble()) {
list.add(scanner.nextDouble());
}
scanner.close();
}
*/
currentBodyTemp = list;
displayBodyTemp("Your Body Temperature Readings are:" + list);
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_body_temp_info);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
try {
displayCurrentBodyTempArray(findViewById(R.id.bodyTempInfoArray));
} catch (FileNotFoundException e) {
e.printStackTrace();
}
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
}
private void displayBodyTemp(String bodyTemp) {
TextView textView = (TextView) findViewById(R.id.bodyTempInfoArray);
textView.setText(bodyTemp);
}
}
日志猫
10-25 14:15:11.041 11084-11084/? E/Zygote: MountEmulatedStorage()
10-25 14:15:11.041 11084-11084/? E/Zygote: v2
10-25 14:15:11.041 11084-11084/? I/libpersona: KNOX_SDCARD checking this for 10385
10-25 14:15:11.041 11084-11084/? I/libpersona: KNOX_SDCARD not a persona
10-25 14:15:11.051 11084-11084/? I/SELinux: Function: selinux_compare_spd_ram , priority [2] , priority version is VE=SEPF_SM-G920V_5.1.1_0033
10-25 14:15:11.051 11084-11084/? E/SELinux: [DEBUG] get_category: variable seinfo: default sensitivity: NULL, cateogry: NULL
10-25 14:15:11.051 11084-11084/? I/art: Late-enabling -Xcheck:jni
10-25 14:15:11.111 11084-11084/? D/TimaKeyStoreProvider: TimaSignature is unavailable
10-25 14:15:11.111 11084-11084/? D/ActivityThread: Added TimaKeyStore provider
10-25 14:15:11.211 11084-11084/com.teamfara.circadianrhythmmonitor4 I/InjectionManager: Inside getClassLibPath + mLibMap{0=, 1=}
10-25 14:15:11.231 11084-11084/com.teamfara.circadianrhythmmonitor4 I/InjectionManager: Inside getClassLibPath caller
10-25 14:15:11.241 11084-11084/com.teamfara.circadianrhythmmonitor4 D/InjectionManager: InjectionManager
10-25 14:15:11.241 11084-11084/com.teamfara.circadianrhythmmonitor4 D/InjectionManager: fillFeatureStoreMap com.teamfara.circadianrhythmmonitor4
10-25 14:15:11.241 11084-11084/com.teamfara.circadianrhythmmonitor4 I/InjectionManager: Constructor com.teamfara.circadianrhythmmonitor4, Feature store :{}
10-25 14:15:11.241 11084-11084/com.teamfara.circadianrhythmmonitor4 I/InjectionManager: featureStore :{}
10-25 14:15:11.301 11084-11084/com.teamfara.circadianrhythmmonitor4 D/SecWifiDisplayUtil: Metadata value : SecSettings2
10-25 14:15:11.491 11084-11084/com.teamfara.circadianrhythmmonitor4 D/PhoneWindow: *FMB* installDecor mIsFloating : false
10-25 14:15:11.491 11084-11084/com.teamfara.circadianrhythmmonitor4 D/PhoneWindow: *FMB* installDecor flags : -2139029248
10-25 14:15:11.761 11084-11084/com.teamfara.circadianrhythmmonitor4 D/Activity: performCreate Call Injection manager
10-25 14:15:11.771 11084-11084/com.teamfara.circadianrhythmmonitor4 I/InjectionManager: dispatchOnViewCreated > Target : com.teamfara.circadianrhythmmonitor4.MainActivity isFragment :false
10-25 14:15:11.791 11084-11175/com.teamfara.circadianrhythmmonitor4 D/OpenGLRenderer: Use EGL_SWAP_BEHAVIOR_PRESERVED: true
10-25 14:15:11.821 11084-11084/com.teamfara.circadianrhythmmonitor4 D/PhoneWindow: *FMB* isFloatingMenuEnabled mFloatingMenuBtn : null
10-25 14:15:11.821 11084-11084/com.teamfara.circadianrhythmmonitor4 D/PhoneWindow: *FMB* isFloatingMenuEnabled return false
10-25 14:15:11.891 11084-11084/com.teamfara.circadianrhythmmonitor4 D/SRIB_DCS: log_dcs ThreadedRenderer::initialize entered!
10-25 14:15:11.951 11084-11175/com.teamfara.circadianrhythmmonitor4 D/libEGL: loaded /vendor/lib64/egl/libGLES_mali.so
10-25 14:15:11.991 11084-11175/com.teamfara.circadianrhythmmonitor4 I/OpenGLRenderer: Initialized EGL, version 1.4
10-25 14:15:12.001 11084-11175/com.teamfara.circadianrhythmmonitor4 I/OpenGLRenderer: HWUI protection enabled for context , &this =0x7f79c8abc0 ,&mEglDisplay = 1 , &mEglConfig = 1912140464
10-25 14:15:12.011 11084-11175/com.teamfara.circadianrhythmmonitor4 D/OpenGLRenderer: Get maximum texture size. GL_MAX_TEXTURE_SIZE is 8192
10-25 14:15:12.011 11084-11175/com.teamfara.circadianrhythmmonitor4 D/OpenGLRenderer: Enabling debug mode 0
10-25 14:15:12.011 11084-11175/com.teamfara.circadianrhythmmonitor4 D/mali_winsys: new_window_surface returns 0x3000, [1440x2560]-format:1
10-25 14:15:12.391 11084-11084/com.teamfara.circadianrhythmmonitor4 I/InjectionManager: dispatchCreateOptionsMenu :com.teamfara.circadianrhythmmonitor4.MainActivity
10-25 14:15:12.391 11084-11084/com.teamfara.circadianrhythmmonitor4 I/InjectionManager: dispatchPrepareOptionsMenu :com.teamfara.circadianrhythmmonitor4.MainActivity
10-25 14:15:12.461 11084-11084/com.teamfara.circadianrhythmmonitor4 I/Timeline: Timeline: Activity_idle id: android.os.BinderProxy@2f8d81aa time:4028871
10-25 14:15:12.801 11084-11084/com.teamfara.circadianrhythmmonitor4 V/ActivityThread: updateVisibility : ActivityRecord{81a0e76 token=android.os.BinderProxy@2f8d81aa {com.teamfara.circadianrhythmmonitor4/com.teamfara.circadianrhythmmonitor4.MainActivity}} show : true
10-25 14:15:14.701 11084-11084/com.teamfara.circadianrhythmmonitor4 I/Timeline: Timeline: Activity_idle id: android.os.BinderProxy@2f8d81aa time:4031112
10-25 14:15:14.921 11084-11084/com.teamfara.circadianrhythmmonitor4 D/ViewRootImpl: ViewPostImeInputStage ACTION_DOWN
10-25 14:15:14.971 11084-11084/com.teamfara.circadianrhythmmonitor4 I/Timeline: Timeline: Activity_launch_request id:com.teamfara.circadianrhythmmonitor4 time:4031384
10-25 14:15:15.051 11084-11084/com.teamfara.circadianrhythmmonitor4 D/PhoneWindow: *FMB* installDecor mIsFloating : false
10-25 14:15:15.051 11084-11084/com.teamfara.circadianrhythmmonitor4 D/PhoneWindow: *FMB* installDecor flags : -2139029248
10-25 14:15:15.071 11084-11084/com.teamfara.circadianrhythmmonitor4 D/Activity: performCreate Call Injection manager
10-25 14:15:15.121 11084-11084/com.teamfara.circadianrhythmmonitor4 I/InjectionManager: dispatchOnViewCreated > Target : com.teamfara.circadianrhythmmonitor4.bodyTempInfo isFragment :false
10-25 14:15:15.121 11084-11084/com.teamfara.circadianrhythmmonitor4 D/SecWifiDisplayUtil: Metadata value : SecSettings2
10-25 14:15:15.141 11084-11084/com.teamfara.circadianrhythmmonitor4 D/PhoneWindow: *FMB* isFloatingMenuEnabled mFloatingMenuBtn : null
10-25 14:15:15.141 11084-11084/com.teamfara.circadianrhythmmonitor4 D/PhoneWindow: *FMB* isFloatingMenuEnabled return false
10-25 14:15:15.181 11084-11084/com.teamfara.circadianrhythmmonitor4 D/SRIB_DCS: log_dcs ThreadedRenderer::initialize entered!
10-25 14:15:15.181 11084-11175/com.teamfara.circadianrhythmmonitor4 D/mali_winsys: new_window_surface returns 0x3000, [1440x2560]-format:1
10-25 14:15:15.201 11084-11084/com.teamfara.circadianrhythmmonitor4 I/InjectionManager: dispatchCreateOptionsMenu :com.teamfara.circadianrhythmmonitor4.bodyTempInfo
10-25 14:15:15.201 11084-11084/com.teamfara.circadianrhythmmonitor4 I/InjectionManager: dispatchPrepareOptionsMenu :com.teamfara.circadianrhythmmonitor4.bodyTempInfo
10-25 14:15:15.271 11084-11084/com.teamfara.circadianrhythmmonitor4 I/Timeline: Timeline: Activity_idle id: android.os.BinderProxy@1f826b14 time:4031688
10-25 14:15:15.311 11084-11084/com.teamfara.circadianrhythmmonitor4 V/ActivityThread: updateVisibility : ActivityRecord{81a0e76 token=android.os.BinderProxy@2f8d81aa {com.teamfara.circadianrhythmmonitor4/com.teamfara.circadianrhythmmonitor4.MainActivity}} show : false
我的 content_body_temp_info.xml 文件:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto" android:layout_width="match_parent"
android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:showIn="@layout/activity_body_temp_info"
tools:context="com.teamfara.circadianrhythmmonitor4.bodyTempInfo">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text = "Body Temperature Measurements will go here"
android:id = "@+id/bodyTempInfoArray"/>
</RelativeLayout>
我的MainActivity.java
package com.teamfara.circadianrhythmmonitor4;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothServerSocket;
import android.bluetooth.BluetoothSocket;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.TextView;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.Set;
import java.util.UUID;
public class MainActivity extends AppCompatActivity {
private final static int REQUEST_ENABLE_BT = 1;
UUID myUUID = UUID.randomUUID();
private static final int DISCOVER_DURATION = 300;
private static final int REQUEST_BLU = 1;
ArrayAdapter<String> mArrayAdapter;
ArrayList<Double> currentBodyTemp;
BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (!mBluetoothAdapter.isEnabled()) {
Intent enableBIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBIntent, REQUEST_ENABLE_BT);
}
//If there are paired devices
/*Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices();
if (pairedDevices.size() > 0) {
//Loop through the paired devices
for (BluetoothDevice device : pairedDevices) {
//add the name and address to an array adapter to show in a ListView
mArrayAdapter.add(device.getName() + "\n" + device.getAddress());
}
}
*/
IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
registerReceiver(mReceiver, filter); // Don't forget to unregister during onDestroy
Intent discoverableIntent = new
Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);
discoverableIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 300);
startActivity(discoverableIntent);
}
ArrayList<Double> lightInfo;
public void sendLightFile() {
String filename = "lightInfo";
String string = "Here is light info" + lightInfo;
FileOutputStream outputStream;
try {
outputStream = openFileOutput(filename, Context.MODE_PRIVATE);
outputStream.write(string.getBytes());
outputStream.close();
} catch (Exception e) {
e.printStackTrace();
}
// Send information over bluetooth?
}
public void goToBodyInfo(View view) {
Intent intent = new Intent(this, bodyTempInfo.class);
startActivity(intent);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
public void sendLight(View view) {
Intent intent = new Intent(this, ConnectTest.class);
startActivity(intent);
}
// Create a BroadcastReceiver for ACTION_FOUND
private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
// When discovery finds a device
if (BluetoothDevice.ACTION_FOUND.equals(action)) {
// Get the BluetoothDevice object from the Intent
BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
// Add the name and address to an array adapter to show in a ListView
mArrayAdapter.add(device.getName() + "\n" + device.getAddress());
}
}
};
private class AcceptThread extends Thread {
private final BluetoothServerSocket mmServerSocket;
BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices();
public AcceptThread() {
// Use a temporary object that is later assigned to mmServerSocket,
// because mmServerSocket is final
BluetoothServerSocket tmp = null;
try {
// MY_UUID is the app's UUID string, also used by the client code
tmp = mBluetoothAdapter.listenUsingRfcommWithServiceRecord("CircadianRhythmMonitor", myUUID);
} catch (IOException e) {
}
mmServerSocket = tmp;
}
public void run() {
BluetoothSocket socket = null;
// Keep listening until exception occurs or a socket is returned
while (true) {
try {
socket = mmServerSocket.accept();
} catch (IOException e) {
break;
}
// If a connection was accepted
if (socket != null) {
// Do work to manage the connection (in a separate thread)
//manageConnectedSocket(socket);
//mmServerSocket.close();
break;
}
}
}
/**
* Will cancel the listening socket, and cause the thread to finish
*/
public void cancel() {
try {
mmServerSocket.close();
} catch (IOException e) {
}
}
}
private class ConnectedThread extends Thread {
private final BluetoothSocket mmSocket;
private final InputStream mmInStream;
private final OutputStream mmOutStream;
public ConnectedThread(BluetoothSocket socket) {
mmSocket = socket;
InputStream tmpIn = null;
OutputStream tmpOut = null;
// Get the input and output streams, using temp objects because
// member streams are final
try {
tmpIn = socket.getInputStream();
tmpOut = socket.getOutputStream();
} catch (IOException e) { }
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run() {
byte[] buffer = new byte[1024]; // buffer store for the stream
int bytes; // bytes returned from read()
// Keep listening to the InputStream until an exception occurs
while (true) {
try {
// Read from the InputStream
bytes = mmInStream.read(buffer);
// Send the obtained bytes to the UI activity
// mHandler.obtainMessage(MESSAGE_READ, bytes, -1, buffer)
//.sendToTarget();
} catch (IOException e) {
break;
}
}
}
/* Call this from the main activity to send data to the remote device */
public void write(byte[] bytes) {
try {
mmOutStream.write(bytes);
} catch (IOException e) { }
}
/* Call this from the main activity to shutdown the connection */
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) { }
}
}
private void displayBodyTemp(String bodyTemp) {
TextView textView = (TextView) findViewById(R.id.bodyTempInfoArray);
textView.setText(bodyTemp);
}
}
我的 AndroidManfiest.xml
package="com.teamfara.circadianrhythmmonitor4" >
<!-- Allows bluetooth to be used from this app -->
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.NFC" />
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="@string/app_name"
android:theme="@style/AppTheme.NoActionBar" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".bodyTempInfo"
android:label="@string/title_activity_body_temp_info"
android:parentActivityName=".MainActivity"
android:theme="@style/AppTheme.NoActionBar" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.teamfara.circadianrhythmmonitor4.MainActivity" />
</activity>
<activity
android:name=".ConnectTest"
android:label="@string/title_activity_body_temp_info"
android:parentActivityName=".MainActivity"
android:theme="@style/AppTheme.NoActionBar" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.teamfara.circadianrhythmmonitor4.MainActivity" />
</activity>
</application>
<uses-feature
android:name="android.hardware.nfc"
android:required="true" />
</manifest>
最佳答案
在 displayBodyTemp() 函数中，您传递一个字符串并使用 + 添加数组列表。这就是故事。您只需要传递一个字符串。或者重写 Arraylist
toString() 方法
或者，试试这个:
displayBodyTemp("Your Body Temperature Readings are:" + text);
关于java - 文件读取不显示任何文件实际数据，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/33333186/