我对Android编程完全陌生，这在技术上是我在Android Studio上工作的第一个大项目。我正在尝试创建一个通过蓝牙连接到我的Arduino设备的Android应用程序，并最终处理.txt文件。
目前，我似乎无法启用蓝牙。当我点击应该要求用户激活蓝牙权限的按钮时，该应用程序会冻结并最终崩溃。
我已经包含了java和logcat。对此事有任何帮助吗？
java文件：
InStrlogcat的：
package com.example.a0111601.testsplash;
import android.app.Activity;
import android.bluetooth.BluetoothSocket;
import android.bluetooth.BluetoothServerSocket;
import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.content.BroadcastReceiver;
import android.content.Context;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Set;
import java.util.UUID;
import android.content.Intent;
import android.content.IntentFilter;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
public class ConnectingScreen extends Activity {
private TextView text;
private ArrayAdapter<String> BTArrayAdapter;
private ListView listView;
public BluetoothAdapter bluetoothAdapter;
private final static UUID uuid = UUID.fromString("fc5ffc49-00e3-4c8b-9cf1-6b72aad1001a");
private Button btn_refresh;
private Button btn_proceed;
private ArrayAdapter adapter;
private static final int ENABLE_BT_REQUEST_CODE = 1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.connecting_screen);
// Initialize items on the screen from layout in order //
// Get bluetooth status //
text = (TextView) findViewById(R.id.status_BT);
bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (!bluetoothAdapter.isEnabled()) { // if bluetooth has not been enabled //
text.setText("Disabled");
} else { // bluetooth has already been enabled //
text.setText("Enabled");
}
// Set up list for selection of available devices //
listView = (ListView) findViewById(R.id.Connecting_devices);
// Click listener on list //
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View v, int position, long id) {
// Cancel discovery because it's costly and we're about to connect
bluetoothAdapter.cancelDiscovery();
// Get the device MAC address, which is the last 17 chars in the View
String info = ((TextView) v).getText().toString();
String address = info.substring(info.length() - 17);
BluetoothDevice bluetoothDevice = bluetoothAdapter.getRemoteDevice(address);
// Initiate a connection request in a separate thread
ConnectingThread t = new ConnectingThread(bluetoothDevice);
t.start();
}
});
BTArrayAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1);
listView.setAdapter(BTArrayAdapter);
// Register for broadcasts when a device is discovered
IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
this.registerReceiver(mReceiver, filter);
// Register for broadcasts when discovery has finished
filter = new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
this.registerReceiver(mReceiver, filter);
// Initialize Refresh button //
btn_refresh = (Button) findViewById(R.id.refresh);
btn_refresh.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
BTArrayAdapter.clear();
while (!bluetoothAdapter.isEnabled()) { // if bluetooth has not been enabled //
// Dialog to request user permission to enable BT //
Intent enableBluetoothIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBluetoothIntent, ENABLE_BT_REQUEST_CODE);
}
if (bluetoothAdapter.isEnabled()) { // bluetooth has already been enabled //
text.setText("Enabled");
// To discover devices //
discoverDevices();
Toast.makeText(getApplicationContext(), "Scanning for devices...", Toast.LENGTH_LONG).show();
}
}
});
btn_proceed = (Button) findViewById(R.id.proceed_footer);
// Source: http://stackoverflow.com/questions/24610527/how-do-i-get-a-button-to-open-another-activity-in-android-studio //
// Proceed button to continue on to next activity //
btn_proceed.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick (View v) {
startActivity(new Intent(ConnectingScreen.this, MainActivity.class));
}
});
// Disable "proceed" button by default to prevent user from going to next activity //
// Source: //
// http://stackoverflow.com/questions/4384890/how-to-disable-an-android-button //
btn_proceed.setEnabled(false);
}
// ConnectingThread method to connect to device selected from list //
private class ConnectingThread extends Thread {
private final BluetoothSocket bluetoothSocket;
private final BluetoothDevice bluetoothDevice;
public ConnectingThread(BluetoothDevice device) {
BluetoothSocket temp = null;
bluetoothDevice = device;
// Get a BluetoothSocket to connect with the selected BluetoothDevice
try {
temp = bluetoothDevice.createRfcommSocketToServiceRecord(uuid);
} catch (IOException e) {
e.printStackTrace();
}
bluetoothSocket = temp;
}
public void run() {
// Cancel discovery first to not slow down connection speed //
bluetoothAdapter.cancelDiscovery();
try {
// bluetoothSocket.connect() to initiate connection request //
// This will block until it succeeds in connecting to the device through the bluetoothSocket or throws an exception //
bluetoothSocket.connect();
} catch (IOException connectException) {
connectException.printStackTrace();
try {
bluetoothSocket.close();
} catch (IOException closeException) {
closeException.printStackTrace();
}
}
if (bluetoothSocket.isConnected()) {
btn_proceed.setEnabled(true);
}
}
}
// discoverDevices() method //
// To scan for other devices //
protected void discoverDevices() {
// If we're already discovering, stop it
if (bluetoothAdapter.isDiscovering()) {
bluetoothAdapter.cancelDiscovery();
}
bluetoothAdapter.startDiscovery();
// to change the bluetooth status accordingly //
if (bluetoothAdapter.startDiscovery()) {
text.setText("Scanning");
Toast.makeText(getApplicationContext(), "Scanning for devices...", Toast.LENGTH_LONG).show();
} else {
text.setText("Error scanning");
Toast.makeText(getApplicationContext(), "Discovery failed to start!", Toast.LENGTH_LONG).show();
}
}
/**
* The BroadcastReceiver that listens for discovered devices and changes the title when
* discovery is finished
*/
private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
@Override
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);
// If it's already paired, skip it, because it's been listed already //
if (device.getBondState() != BluetoothDevice.BOND_BONDED) {
BTArrayAdapter.add(device.getName() + "\n" + device.getAddress());
}
// When discovery is finished, change the Activity title //
} else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)) {
Toast.makeText(getApplicationContext(), "Select device to pair with", Toast.LENGTH_LONG).show();
text.setText("Select device from list");
if (BTArrayAdapter.getCount() == 0) {
text.setText("No devices found");
String noDevices = getResources().getText(R.string.none_found).toString();
BTArrayAdapter.add(noDevices);
}
}
}
};
@Override
protected void onDestroy() {
super.onDestroy();
// Make sure we're not doing discovery anymore
if (bluetoothAdapter != null) {
bluetoothAdapter.cancelDiscovery();
}
// Unregister broadcast listeners
this.unregisterReceiver(mReceiver);
}
}
清单：
10-20 14:52:23.693 6976-6976/? E/Zygote: MountEmulatedStorage()
10-20 14:52:23.693 6976-6976/? E/Zygote: v2
10-20 14:52:23.693 6976-6976/? I/libpersona: KNOX_SDCARD checking this for 10065
10-20 14:52:23.693 6976-6976/? I/libpersona: KNOX_SDCARD not a persona
10-20 14:52:23.693 6976-6976/? I/SELinux: Function: selinux_compare_spd_ram, SPD-policy is existed. and_ver=SEPF_GT-I9505_5.0.1 ver=27
10-20 14:52:23.693 6976-6976/? I/SELinux: Function: selinux_compare_spd_ram , priority [2] , priority version is VE=SEPF_GT-I9505_5.0.1-1_0032
10-20 14:52:23.703 6976-6976/? E/SELinux: [DEBUG] get_category: variable seinfo: default sensitivity: NULL, cateogry: NULL
10-20 14:52:23.703 6976-6976/? I/art: Late-enabling -Xcheck:jni
10-20 14:52:23.723 6976-6983/? E/art: Failed sending reply to debugger: Broken pipe
10-20 14:52:23.723 6976-6983/? I/art: Debugger is no longer active
10-20 14:52:23.753 6976-6976/? D/ResourcesManager: creating new AssetManager and set to /data/app/com.example.a0111601.testsplash-2/base.apk
10-20 14:52:23.943 6976-6976/? D/Activity: performCreate Call secproduct feature valuefalse
10-20 14:52:23.943 6976-6976/? D/Activity: performCreate Call debug elastic valuetrue
10-20 14:52:23.953 6976-7015/? D/OpenGLRenderer: Render dirty regions requested: true
10-20 14:52:23.983 6976-7015/? I/Adreno-EGL: <qeglDrvAPI_eglInitialize:410>: EGL 1.4 QUALCOMM build: ()
10-20 14:52:23.983 6976-7015/? I/Adreno-EGL: OpenGL ES Shader Compiler Version: E031.25.03.06
10-20 14:52:23.983 6976-7015/? I/Adreno-EGL: Build Date: 01/24/15 Sat
10-20 14:52:23.983 6976-7015/? I/Adreno-EGL: Local Branch: AF11_RB1_AU15
10-20 14:52:23.983 6976-7015/? I/Adreno-EGL: Remote Branch:
10-20 14:52:23.983 6976-7015/? I/Adreno-EGL: Local Patches:
10-20 14:52:23.983 6976-7015/? I/Adreno-EGL: Reconstruct Branch:
10-20 14:52:23.983 6976-7015/? I/OpenGLRenderer: Initialized EGL, version 1.4
10-20 14:52:24.013 6976-7015/? D/OpenGLRenderer: Enabling debug mode 0
10-20 14:52:24.674 6976-6976/? I/Timeline: Timeline: Activity_idle id: android.os.BinderProxy@29f66b0b time:6733391
10-20 14:52:25.735 6976-6983/com.example.a0111601.testsplash I/art: Ignoring second debugger -- accepting and dropping
10-20 14:52:26.736 6976-7014/? I/Timeline: Timeline: Activity_launch_request id:com.example.a0111601.testsplash time:6735467
10-20 14:52:26.816 6976-6976/? D/AbsListView: Get MotionRecognitionManager
10-20 14:52:26.836 6976-6976/? D/Activity: performCreate Call secproduct feature valuefalse
10-20 14:52:26.836 6976-6976/? D/Activity: performCreate Call debug elastic valuetrue
10-20 14:52:27.066 6976-6976/? I/Timeline: Timeline: Activity_idle id: android.os.BinderProxy@21202ee1 time:6735796
10-20 14:53:00.079 6976-6976/? I/Timeline: Timeline: Activity_idle id: android.os.BinderProxy@21202ee1 time:6768804
10-20 14:54:12.720 6976-6976/? D/ViewRootImpl: ViewPostImeInputStage ACTION_DOWN
10-20 14:54:14.441 6976-6976/? D/ViewRootImpl: ViewPostImeInputStage ACTION_DOWN
10-20 14:54:14.952 6976-6976/? D/ViewRootImpl: ViewPostImeInputStage ACTION_DOWN
10-20 14:54:17.514 6976-6976/? D/ViewRootImpl: ViewPostImeInputStage ACTION_DOWN
10-20 15:04:08.991 6976-6976/? D/AndroidRuntime: Shutting down VM
10-20 15:04:09.021 6976-6976/? E/AndroidRuntime: FATAL EXCEPTION: main
10-20 15:04:09.021 6976-6976/? E/AndroidRuntime: Process: com.example.a0111601.testsplash, PID: 6976
10-20 15:04:09.021 6976-6976/? E/AndroidRuntime: java.lang.SecurityException: Need BLUETOOTH permission: Neither user 10065 nor current process has android.permission.BLUETOOTH.
10-20 15:04:09.021 6976-6976/? E/AndroidRuntime: at android.os.Parcel.readException(Parcel.java:1540)
10-20 15:04:09.021 6976-6976/? E/AndroidRuntime: at android.os.Parcel.readException(Parcel.java:1493)
10-20 15:04:09.021 6976-6976/? E/AndroidRuntime: at android.bluetooth.IBluetooth$Stub$Proxy.isEnabled(IBluetooth.java:1156)
10-20 15:04:09.021 6976-6976/? E/AndroidRuntime: at android.bluetooth.BluetoothAdapter.isEnabled(BluetoothAdapter.java:695)
10-20 15:04:09.021 6976-6976/? E/AndroidRuntime: at com.example.a0111601.testsplash.ConnectingScreen$2.onClick(ConnectingScreen.java:93)
10-20 15:04:09.021 6976-6976/? E/AndroidRuntime: at android.view.View.performClick(View.java:5197)
10-20 15:04:09.021 6976-6976/? E/AndroidRuntime: at android.view.View$PerformClick.run(View.java:20926)
10-20 15:04:09.021 6976-6976/? E/AndroidRuntime: at android.os.Handler.handleCallback(Handler.java:739)
10-20 15:04:09.021 6976-6976/? E/AndroidRuntime: at android.os.Handler.dispatchMessage(Handler.java:95)
10-20 15:04:09.021 6976-6976/? E/AndroidRuntime: at android.os.Looper.loop(Looper.java:145)
10-20 15:04:09.021 6976-6976/? E/AndroidRuntime: at android.app.ActivityThread.main(ActivityThread.java:5942)
10-20 15:04:09.021 6976-6976/? E/AndroidRuntime: at java.lang.reflect.Method.invoke(Native Method)
10-20 15:04:09.021 6976-6976/? E/AndroidRuntime: at java.lang.reflect.Method.invoke(Method.java:372)
10-20 15:04:09.021 6976-6976/? E/AndroidRuntime: at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1400)
10-20 15:04:09.021 6976-6976/? E/AndroidRuntime: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1195)
10-20 15:04:09.031 6976-6976/? E/AndroidRuntime: Error reporting crash
10-20 15:04:09.031 6976-6976/? E/AndroidRuntime: android.os.DeadObjectException
10-20 15:04:09.031 6976-6976/? E/AndroidRuntime: at android.os.BinderProxy.transactNative(Native Method)
10-20 15:04:09.031 6976-6976/? E/AndroidRuntime: at android.os.BinderProxy.transact(Binder.java:496)
10-20 15:04:09.031 6976-6976/? E/AndroidRuntime: at android.app.ActivityManagerProxy.handleApplicationCrash(ActivityManagerNative.java:4686)
10-20 15:04:09.031 6976-6976/? E/AndroidRuntime: at com.android.internal.os.RuntimeInit$UncaughtHandler.uncaughtException(RuntimeInit.java:95)
10-20 15:04:09.031 6976-6976/? E/AndroidRuntime: at java.lang.ThreadGroup.uncaughtException(ThreadGroup.java:693)
10-20 15:04:09.031 6976-6976/? E/AndroidRuntime: at java.lang.ThreadGroup.uncaughtException(ThreadGroup.java:690)
10-20 15:04:09.031 6976-6976/? I/Process: Sending signal. PID: 6976 SIG: 9
答案 0 :(得分：3)
function答案 1 :(得分：-1)
为蓝牙管理员添加以下权限：
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>