android首选项导致错误

Question

我正在尝试在我的应用程序中添加一些首选项功能。我希望应用程序能够加载在XML文件中设置的默认值，然后能够在以后更改这些值。我遇到了首选项，并一直试图在代码中实现。我编写了下面的代码，当试图在“//从这里开始运行”和“//结束这里”的“SmartApp类中的注释”之间运行代码时，它不会启动我的gui (屏幕是空白的，似乎没有做任何事情)，并给出了下面的logcat消息。当我使用注释掉的区域运行时，应用程序将正常运行。能不能有人看看我有什么，看看我可能做错了什么，或者有什么建议，我可能需要解决这个问题？如果您有任何问题或需要更多的信息，请告诉我。预先感谢，如果我找到了解决方案，我会在这里发布。

//The log cat messages
02-01 22:49:19.653: INFO/ActivityManager(59): Displayed activity com.android.launcher/com.android.launcher2.Launcher: 43150 ms (total 43150 ms)
02-01 22:49:24.513: WARN/ActivityManager(59): Launch timeout has expired, giving up wake lock!
02-01 22:49:25.560: WARN/ActivityManager(59): Activity idle timeout for HistoryRecord{43f017d0 cpe495.smartapp/.SmartApp}
02-01 22:49:29.393: DEBUG/KeyguardViewMediator(59): pokeWakelock(5000)
02-01 22:49:29.613: DEBUG/KeyguardViewMediator(59): pokeWakelock(5000)
02-01 22:49:29.862: INFO/ARMAssembler(59): generated scanline__00000077:03545404_00000004_00000000 [ 47 ipp] (67 ins) at [0x337450:0x33755c] in 1480914 ns
02-01 22:49:29.952: INFO/ARMAssembler(59): generated scanline__00000177:03515104_00001001_00000000 [ 91 ipp] (114 ins) at [0x337560:0x337728] in 1085613 ns
02-01 22:53:59.112: DEBUG/SntpClient(59): request time failed: java.net.SocketException: Address family not supported by protocol    

//The Array Values
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string-array name="heartRateBaseArray">
<item>10 bpm</item>
<item>20 bpm</item>
<item>30 bpm</item>
<item>40 bpm</item>
<item>50 bpm</item>
<item>60 bpm</item>
<item>70 bpm</item>
<item>80 bpm</item>
<item>90 bpm</item>
<item>100 bpm</item>
</string-array>
<string-array name="heartRateBaseValues">
<item>10</item>
<item>20</item>
<item>30</item>
<item>40</item>
<item>50</item>
<item>60</item>
<item>70</item>
<item>80</item>
<item>90</item>
<item>100</item>
</string-array>
<string-array name="sI1Array">
<item>0</item>
<item>5</item>
<item>10</item>
<item>15</item>
<item>20</item>
<item>25</item>
<item>30</item>
<item>35</item>
<item>40</item>
<item>45</item>
<item>50</item>
<item>55</item>
<item>60</item>
<item>65</item>
<item>70</item>
<item>75</item>
<item>80</item>
<item>85</item>
<item>90</item>
<item>95</item>
<item>100</item>
</string-array>
<string-array name="sI1Values">
<item>0</item>
<item>5</item>
<item>10</item>
<item>15</item>
<item>20</item>
<item>25</item>
<item>30</item>
<item>35</item>
<item>40</item>
<item>45</item>
<item>50</item>
<item>55</item>
<item>60</item>
<item>65</item>
<item>70</item>
<item>75</item>
<item>80</item>
<item>85</item>
<item>90</item>
<item>95</item>
<item>100</item>
</string-array>
</resources>  

//The settings.xml file
<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen
  xmlns:android="http://schemas.android.com/apk/res/android">
<PreferenceCategory android:title="Profile Settings">
<EditTextPreference android:title="First Name" android:key="firstNameKey" android:selectable="false"></EditTextPreference><EditTextPreference android:title="Last Name" android:key="lastNameKey" android:selectable="false"></EditTextPreference>
<EditTextPreference android:title="User Name" android:key="userNameKey" android:selectable="false"></EditTextPreference>
<EditTextPreference android:title="Birth Date" android:key="birthDateKey" android:selectable="false"></EditTextPreference>
</PreferenceCategory>
<PreferenceCategory android:title="Configuration Settings"><ListPreference android:title="Medium Stress Index Threshold" android:entryValues="@array/sI1Values" android:entries="@array/sI1Array" android:key="sI1Key"></ListPreference><ListPreference android:title="High Stress Index Threshold" android:entryValues="@array/sI1Values" android:entries="@array/sI1Array" android:key="sI2Key"></ListPreference><EditTextPreference android:title="Weight 1" android:key="weight1Key"></EditTextPreference>
<EditTextPreference android:title="Weight 2" android:key="weight2Key"></EditTextPreference>
<EditTextPreference android:title="Weight 3" android:key="weight3Key"></EditTextPreference>

<ListPreference android:entryValues="@array/heartRateBaseValues" android:entries="@array/heartRateBaseArray" android:defaultValue="60" android:key="heartRateBaseKey" android:title="Heart Rate Base"></ListPreference>
<EditTextPreference android:title="Heart Rate Variability Minimum" android:key="hRVMinKey"></EditTextPreference>
<EditTextPreference android:title="Heart Rate Variability Maximum" android:key="hRVMaxKey"></EditTextPreference>


</PreferenceCategory>
</PreferenceScreen>   

//The preferences class
package cpe495.smartapp;

import android.os.Bundle;
import android.preference.PreferenceActivity;

public class Preferences extends PreferenceActivity {
    public void onCreate(Bundle savedInstanceState) {
        addPreferencesFromResource(R.xml.settings);
    }
}   

//The Main Class
public class SmartApp extends Activity implements OnSharedPreferenceChangeListener {
    TextView smartConnectionStatus;
    TextView testOutputView;
    Thread cThread;
    private ConnectDevice cD = new ConnectDevice();
    private DataRobot dR = new DataRobot();
    private DataBuilder dB = new DataBuilder();
    private DataSender dS = new DataSender();
    public SmartApp() {
        /* Constructor */
        cD.addDataReceivedListener(new DataReceivedListener() {
            @Override
            public void dataReceivedReceived(DataReceivedEvent event) {
                // TODO Auto-generated method stub
                dR.analyzeData(event.getData());
            }
        });
        dR.addDataAnalyzedListener(new DataAnalyzedListener() {
            @Override
            public void dataAnalyzedReceived(DataAnalyzedEvent event) {
                // TODO Auto-generated method stub
                dB.submitData(event.getData());
            }
        });
        dB.addDataBuilderListener(new DataBuilderListener() {
            @Override
            public void dataBuilderReceived(DataBuilderEvent event) {
                // TODO Auto-generated method stub
                dS.sendData(event.getData());
            }
        });
    }
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.intro);

        //STARTING HERE
        SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);

        prefs.registerOnSharedPreferenceChangeListener(this);

        //set remembered preferences
        dR.sethRB(Integer.parseInt((prefs.getString("heartRateBaseKey", null))));
        dR.sethRVMax(Integer.parseInt((prefs.getString("hRVMaxKey", null))));
        dR.sethRVMin(Integer.parseInt((prefs.getString("hRVMinKey", null))));
        dR.setsI1(Integer.parseInt((prefs.getString("sI1Key", null))));
        dR.setsI2(Integer.parseInt((prefs.getString("sI2Key", null))));
        dR.setW1(Integer.parseInt((prefs.getString("weight1Key", null))));
        dR.setW2(Integer.parseInt((prefs.getString("weight2Key", null))));
        dR.setW3(Integer.parseInt((prefs.getString("weight3Key", null))));
        //ENDING HERE            


        smartConnectionStatus = (TextView) findViewById(R.id.smartConnectionStatus);
        testOutputView = (TextView) findViewById(R.id.testingOutput);

        final Button firstTimeButton = (Button) findViewById(R.id.firstTimeButton);
        firstTimeButton.setOnClickListener(
        new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                Intent userCreationIntent = new Intent(v.getContext(), UserCreation.class);
                startActivityForResult(userCreationIntent, 0);

            }
        });

        final Button connectDeviceButton = (Button) findViewById(R.id.connectDeviceButton);
        connectDeviceButton.setOnClickListener(
        new View.OnClickListener() {    
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                //Intent connectDeviceIntent = new Intent(v.getContext(), ConnectDevice.class);
                //startActivityForResult(connectDeviceIntent, 0);

                cThread = new Thread(cD);
                cThread.start();
            }
        });

        final Button disconnectDeviceButton = (Button) findViewById(R.id.disconnectDeviceButton);
        disconnectDeviceButton.setOnClickListener(
        new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                cD.setConnected(false);
            }
        });
    }
    @Override
    public void onSharedPreferenceChanged(SharedPreferences prefs,
            String key) {
        // TODO Auto-generated method stub
        if(key.equals("heartRateBaseKey")) {
            dR.sethRB(Integer.parseInt((prefs.getString("heartRateBaseKey", null))));
        }
        else if(key.equals("hRVMaxKey")) {
            dR.sethRVMax(Integer.parseInt((prefs.getString("hRVMaxKey", null))));
        }
        else if(key.equals("hRVMinKey")) {
            dR.sethRVMin(Integer.parseInt((prefs.getString("hRVMinKey", null))));
        }
        else if(key.equals("sI1Key")) {
            dR.setsI1(Integer.parseInt((prefs.getString("sI1Key", null))));
        }
        else if(key.equals("sI2Key")) {
            dR.setsI2(Integer.parseInt((prefs.getString("sI2Key", null))));
        }
        else if(key.equals("weight1Key")) {
            dR.setW1(Integer.parseInt((prefs.getString("weight1Key", null))));
        }
        else if(key.equals("weight2Key")) {
            dR.setW2(Integer.parseInt((prefs.getString("weight2Key", null))));
        }
        else if(key.equals("weight3Key")) {
            dR.setW3(Integer.parseInt((prefs.getString("weight3Key", null))));
        }
    }
}

Answer 1

我认为这个代码有几个问题。首先，当从您的首选项加载时，您拥有的默认值都是null。Integer#parseInt()的文档声明，如果您传入null，它将抛出一个null。使用0或其他值代替。

其次，我认为您对dR方法的所有调用都需要很长时间才能完成。这些功能是做什么的？我敢打赌，它们在某种程度上是密集的任务，而且由于它们在您的onCreate()方法中，操作系统认为您的应用程序启动时间太长，从而杀死了它。将这些调用移到AsyncTask中，以便在后台加载它们。

• AsyncTask
• 无痛线程