我正在从事一个学期项目，而且我是java和Android应用程序开发的新手。不过，我有其他编程语言的经验。我试图对应用程序进行逆向工程，使其能够通过蓝牙连接和发送数据。我想列出所有可用的蓝牙设备，一个用于打开/关闭蓝牙的按钮，一个用于使手机可被其他设备发现，另一个用于搜索未配对的设备。但每次我向onCreate方法添加一个OnClickListener时，应用程序在打开之前就会崩溃。谁能帮助我？
我想修改的应用程序的源代码可以在这里找到： https://github.com/pazaan/600SeriesAndroidUploader
这部分似乎让它崩溃了：
lvNewDevices.setOnItemClickListener(MainActivity.this);
btnONOFF.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Log.d(TAG, "onClick: enabling/disabling bluetooth.");
enableDisableBT();
}
});
btnStartConnection.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
startConnection();
}
});
btnSend.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
byte[] bytes = etSend.getText().toString().getBytes(Charset.defaultCharset());
mBluetoothConnection.write(bytes);
}
});
以下是OnCreate的所有内容：
@Override
public void onCreate(Bundle savedInstanceState) {
Log.i(TAG, "onCreate called");
super.onCreate(savedInstanceState);
Button btnONOFF = (Button) findViewById(R.id.btnONOFF);
btnEnableDisable_Discoverable = (Button) findViewById(R.id.btnDiscoverable_on_off);
lvNewDevices = (ListView) findViewById(R.id.lvNewDevices);
mBTDevices = new ArrayList<>();
btnStartConnection = (Button) findViewById(R.id.btnStartConnection);
//Broadcasts when bond state changes (ie:pairing)
IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_BOND_STATE_CHANGED);
registerReceiver(mBroadcastReceiver4, filter);
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
//FUCKUP:
lvNewDevices.setOnItemClickListener(MainActivity.this);
btnONOFF.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Log.d(TAG, "onClick: enabling/disabling bluetooth.");
enableDisableBT();
}
});
btnStartConnection.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
startConnection();
}
});
btnSend.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
byte[] bytes = etSend.getText().toString().getBytes(Charset.defaultCharset());
mBluetoothConnection.write(bytes);
}
});
mRealm = Realm.getDefaultInstance();
RealmResults<PumpStatusEvent> data = mRealm.where(PumpStatusEvent.class)
.findAllSorted("eventDate", Sort.DESCENDING);
if (data.size() > 0)
dataStore.setLastPumpStatus(data.first());
setContentView(R.layout.activity_main);
PreferenceManager.getDefaultSharedPreferences(getBaseContext()).registerOnSharedPreferenceChangeListener(this);
prefs = PreferenceManager.getDefaultSharedPreferences(getBaseContext());
if (!prefs.getBoolean(getString(R.string.preference_eula_accepted), false)) {
stopCgmService();
}
// setup preferences
configurationStore.setPollInterval(Long.parseLong(prefs.getString("pollInterval", Long.toString(MedtronicCnlIntentService.POLL_PERIOD_MS))));
configurationStore.setLowBatteryPollInterval(Long.parseLong(prefs.getString("lowBatPollInterval", Long.toString(MedtronicCnlIntentService.LOW_BATTERY_POLL_PERIOD_MS))));
configurationStore.setReducePollOnPumpAway(prefs.getBoolean("doublePollOnPumpAway", false));
chartZoom = Integer.parseInt(prefs.getString("chartZoom", "3"));
configurationStore.setMmolxl(prefs.getBoolean("mmolxl", false));
configurationStore.setMmolxlDecimals(prefs.getBoolean("mmolDecimals", false));
// Disable battery optimization to avoid missing values on 6.0+
// taken from https://github.com/NightscoutFoundation/xDrip/blob/master/app/src/main/java/com/eveningoutpost/dexdrip/Home.java#L277L298
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
final String packageName = getPackageName();
final PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
if (!pm.isIgnoringBatteryOptimizations(packageName)) {
Log.d(TAG, "Requesting ignore battery optimization");
try {
// ignoring battery optimizations required for constant connection
// to peripheral device - eg CGM transmitter.
final Intent intent = new Intent();
intent.setAction(Settings.ACTION_REQUEST_IGNORE_BATTERY_OPTIMIZATIONS);
intent.setData(Uri.parse("package:" + packageName));
startActivity(intent);
} catch (ActivityNotFoundException e) {
Log.d(TAG, "Device does not appear to support battery optimization whitelisting!");
}
}
}
LocalBroadcastManager.getInstance(this).registerReceiver(
statusMessageReceiver,
new IntentFilter(MedtronicCnlIntentService.Constants.ACTION_STATUS_MESSAGE));
LocalBroadcastManager.getInstance(this).registerReceiver(
new UpdatePumpReceiver(),
new IntentFilter(MedtronicCnlIntentService.Constants.ACTION_UPDATE_PUMP));
mEnableCgmService = Eula.show(this, prefs);
IntentFilter batteryIntentFilter = new IntentFilter();
batteryIntentFilter.addAction(Intent.ACTION_BATTERY_LOW);
batteryIntentFilter.addAction(Intent.ACTION_BATTERY_CHANGED);
batteryIntentFilter.addAction(Intent.ACTION_BATTERY_OKAY);
registerReceiver(batteryReceiver, batteryIntentFilter);
IntentFilter usbIntentFilter = new IntentFilter();
usbIntentFilter.addAction(UsbManager.ACTION_USB_DEVICE_ATTACHED);
usbIntentFilter.addAction(UsbManager.ACTION_USB_DEVICE_DETACHED);
usbIntentFilter.addAction(MedtronicCnlIntentService.Constants.ACTION_USB_PERMISSION);
registerReceiver(usbReceiver, usbIntentFilter);
LocalBroadcastManager.getInstance(this).registerReceiver(
usbReceiver,
new IntentFilter(MedtronicCnlIntentService.Constants.ACTION_NO_USB_PERMISSION));
LocalBroadcastManager.getInstance(this).registerReceiver(
usbReceiver,
new IntentFilter(MedtronicCnlIntentService.Constants.ACTION_USB_REGISTER));
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
if (toolbar != null) {
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(false);
getSupportActionBar().setElevation(0);
getSupportActionBar().setTitle("Nightscout");
}
final PrimaryDrawerItem itemSettings = new PrimaryDrawerItem()
.withName("Settings")
.withIcon(GoogleMaterial.Icon.gmd_settings)
.withSelectable(false);
final PrimaryDrawerItem itemRegisterUsb = new PrimaryDrawerItem()
.withName("Registered devices")
.withIcon(GoogleMaterial.Icon.gmd_usb)
.withSelectable(false);
final PrimaryDrawerItem itemStopCollecting = new PrimaryDrawerItem()
.withName("Stop collecting data")
.withIcon(GoogleMaterial.Icon.gmd_power_settings_new)
.withSelectable(false);
final PrimaryDrawerItem itemGetNow = new PrimaryDrawerItem()
.withName("Read data now")
.withIcon(GoogleMaterial.Icon.gmd_refresh)
.withSelectable(false);
final PrimaryDrawerItem itemUpdateProfile = new PrimaryDrawerItem()
.withName("Update pump profile")
.withIcon(GoogleMaterial.Icon.gmd_insert_chart)
.withSelectable(false);
final PrimaryDrawerItem itemClearLog = new PrimaryDrawerItem()
.withName("Clear log")
.withIcon(GoogleMaterial.Icon.gmd_clear_all)
.withSelectable(false);
final PrimaryDrawerItem itemCheckForUpdate = new PrimaryDrawerItem()
.withName("Check for App update")
.withIcon(GoogleMaterial.Icon.gmd_update)
.withSelectable(false);
assert toolbar != null;
new DrawerBuilder()
.withActivity(this)
.withAccountHeader(new AccountHeaderBuilder()
.withActivity(this)
.withHeaderBackground(R.drawable.drawer_header)
.build()
)
.withTranslucentStatusBar(false)
.withToolbar(toolbar)
.withActionBarDrawerToggle(true)
.withSelectedItem(-1)
.addDrawerItems(
itemSettings,
//itemUpdateProfile, // TODO - re-add when we to add Basal Profile Upload
itemRegisterUsb,
itemCheckForUpdate,
itemClearLog,
itemGetNow,
itemStopCollecting
)
.withOnDrawerItemClickListener(new Drawer.OnDrawerItemClickListener() {
@Override
public boolean onItemClick(View view, int position, IDrawerItem drawerItem) {
if (drawerItem.equals(itemSettings)) {
openSettings();
} else if (drawerItem.equals(itemRegisterUsb)) {
openUsbRegistration();
} else if (drawerItem.equals(itemStopCollecting)) {
mEnableCgmService = false;
stopCgmService();
finish();
} else if (drawerItem.equals(itemGetNow)) {
// It was triggered by user so start reading of data now and not based on last poll.
sendStatus("Requesting poll now...");
startCgmService(System.currentTimeMillis() + 1000);
} else if (drawerItem.equals(itemClearLog)) {
clearLogText();
} else if (drawerItem.equals(itemCheckForUpdate)) {
checkForUpdateNow();
}
return false;
}
})
.build();
mTextViewLog = (TextView) findViewById(R.id.textview_log);
mScrollView = (ScrollView) findViewById(R.id.scrollView);
mScrollView.setSmoothScrollingEnabled(true);
mChart = (GraphView) findViewById(R.id.chart);
// disable scrolling at the moment
mChart.getViewport().setScalable(false);
mChart.getViewport().setScrollable(false);
mChart.getViewport().setYAxisBoundsManual(true);
mChart.getViewport().setMinY(80);
mChart.getViewport().setMaxY(120);
mChart.getViewport().setXAxisBoundsManual(true);
final long now = System.currentTimeMillis(),
left = now - chartZoom * 60 * 60 * 1000;
mChart.getViewport().setMaxX(now);
mChart.getViewport().setMinX(left);
// due to bug in GraphView v4.2.1 using setNumHorizontalLabels reverted to using v4.0.1 and setOnXAxisBoundsChangedListener is n/a in this version
/*
mChart.getViewport().setOnXAxisBoundsChangedListener(new Viewport.OnXAxisBoundsChangedListener() {
@Override
public void onXAxisBoundsChanged(double minX, double maxX, Reason reason) {
double rightX = mChart.getSeries().get(0).getHighestValueX();
hasZoomedChart = (rightX != maxX || rightX - chartZoom * 60 * 60 * 1000 != minX);
}
});
*/
mChart.setOnLongClickListener(new View.OnLongClickListener() {
@Override
public boolean onLongClick(View v) {
if (!mChart.getSeries().isEmpty() && !mChart.getSeries().get(0).isEmpty()) {
double rightX = mChart.getSeries().get(0).getHighestValueX();
mChart.getViewport().setMaxX(rightX);
mChart.getViewport().setMinX(rightX - chartZoom * 60 * 60 * 1000);
}
hasZoomedChart = false;
return true;
}
});
mChart.getGridLabelRenderer().setNumHorizontalLabels(6);
// due to bug in GraphView v4.2.1 using setNumHorizontalLabels reverted to using v4.0.1 and setHumanRounding is n/a in this version
// mChart.getGridLabelRenderer().setHumanRounding(false);
mChart.getGridLabelRenderer().setLabelFormatter(
new DefaultLabelFormatter() {
DateFormat mFormat = new SimpleDateFormat("HH:mm", Locale.US); // 24 hour format forced to fix label overlap
@Override
public String formatLabel(double value, boolean isValueX) {
if (isValueX) {
return mFormat.format(new Date((long) value));
} else {
return MainActivity.strFormatSGV(value);
}
}
}
);
}
这是logcat输出：
09-26 12:38:19.826 6324-6324/? I/art: Late-enabling -Xcheck:jni
09-26 12:38:20.157 6324-6324/info.nightscout.android E/Fabric: Failure onPreExecute()
java.lang.IllegalArgumentException: Fabric could not be initialized, API key missing from AndroidManifest.xml. Add the following tag to your Application element
<meta-data android:name="io.fabric.ApiKey" android:value="YOUR_API_KEY"/>
at io.fabric.sdk.android.services.common.ApiKey.logErrorOrThrowException(ApiKey.java:110)
at io.fabric.sdk.android.services.common.ApiKey.getValue(ApiKey.java:61)
at com.crashlytics.android.core.CrashlyticsCore.onPreExecute(CrashlyticsCore.java:219)
at com.crashlytics.android.core.CrashlyticsCore.onPreExecute(CrashlyticsCore.java:207)
at io.fabric.sdk.android.InitializationTask.onPreExecute(InitializationTask.java:44)
at io.fabric.sdk.android.services.concurrency.AsyncTask.executeOnExecutor(AsyncTask.java:611)
at io.fabric.sdk.android.services.concurrency.PriorityAsyncTask.executeOnExecutor(PriorityAsyncTask.java:43)
at io.fabric.sdk.android.Kit.initialize(Kit.java:69)
at io.fabric.sdk.android.Fabric.initializeKits(Fabric.java:440)
at io.fabric.sdk.android.Fabric.init(Fabric.java:384)
at io.fabric.sdk.android.Fabric.setFabric(Fabric.java:342)
at io.fabric.sdk.android.Fabric.with(Fabric.java:313)
at info.nightscout.android.UploaderApplication.onCreate(UploaderApplication.java:32)
at android.app.Instrumentation.callApplicationOnCreate(Instrumentation.java:1046)
at android.app.ActivityThread.handleBindApplication(ActivityThread.java:5402)
at android.app.ActivityThread.-wrap2(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1541)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6123)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:757)
09-26 12:38:20.202 6324-6379/info.nightscout.android E/Fabric: Error dealing with settings
java.lang.IllegalArgumentException: Fabric could not be initialized, API key missing from AndroidManifest.xml. Add the following tag to your Application element
<meta-data android:name="io.fabric.ApiKey" android:value="YOUR_API_KEY"/>
at io.fabric.sdk.android.services.common.ApiKey.logErrorOrThrowException(ApiKey.java:110)
at io.fabric.sdk.android.services.common.ApiKey.getValue(ApiKey.java:61)
at io.fabric.sdk.android.services.settings.Settings.initialize(Settings.java:78)
at io.fabric.sdk.android.Onboarding.retrieveSettingsData(Onboarding.java:124)
at io.fabric.sdk.android.Onboarding.doInBackground(Onboarding.java:99)
at io.fabric.sdk.android.Onboarding.doInBackground(Onboarding.java:45)
at io.fabric.sdk.android.InitializationTask.doInBackground(InitializationTask.java:63)
at io.fabric.sdk.android.InitializationTask.doInBackground(InitializationTask.java:28)
at io.fabric.sdk.android.services.concurrency.AsyncTask$2.call(AsyncTask.java:311)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:428)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)
at java.lang.Thread.run(Thread.java:761)
09-26 12:38:20.252 6324-6324/info.nightscout.android W/art: Before Android 4.1, method android.graphics.PorterDuffColorFilter android.support.graphics.drawable.VectorDrawableCompat.updateTintFilter(android.graphics.PorterDuffColorFilter, android.content.res.ColorStateList, android.graphics.PorterDuff$Mode) would have incorrectly overridden the package-private method in android.graphics.drawable.Drawable
09-26 12:38:20.349 6324-6324/info.nightscout.android I/MainActivity: onCreate called
09-26 12:38:20.652 6324-6324/info.nightscout.android D/AndroidRuntime: Shutting down VM
09-26 12:38:20.652 6324-6324/info.nightscout.android E/AndroidRuntime: FATAL EXCEPTION: main
Process: info.nightscout.android, PID: 6324
java.lang.RuntimeException: Unable to start activity ComponentInfo{info.nightscout.android/info.nightscout.android.medtronic.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.view.View.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2659)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2724)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1473)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6123)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:757)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.view.View.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
at info.nightscout.android.medtronic.MainActivity.onCreate(MainActivity.java:349)
at android.app.Activity.performCreate(Activity.java:6672)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1140)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2612)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2724)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1473)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6123)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:757)
答案 0 :(得分：4)
移动代码df.applymap(dict_).values.sum()
{'a': 1,
'b': 2,
'c': 3,
'd': 1,
'e': 2,
'f': 3,
'g': 1,
'h': 2,
'i': 3,
'j': 1,
'k': 2,
'l': 3,
'm': 1,
'n': 2,
'o': 3,
'p': 1,
'q': 2,
'r': 3}
在setContentView(R.layout.activity_main);
答案 1 :(得分：0)
在代码中添加布局之前映射视图。 你的onCreate（）应该是
@Override
public void onCreate(Bundle savedInstanceState) {
Log.i(TAG, "onCreate called");
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//Do mapping all views
答案 2 :(得分：0)
您的错误日志显示您的解决方案。该项目正在使用Fabric API。因此，您需要在项目中添加Fabric API密钥。
按错误日志中的建议操作。在Android Manifest中添加以下行。
<meta-data android:name="io.fabric.ApiKey" android:value="YOUR_API_KEY"/>
对于您的API密钥，请使用Fabric帐户创建项目并获取API密钥。