Crash fixes

src/main/java/org/amahi/anywhere/activity/ServerAppActivity.java

@@ -220,7 +220,9 @@ private void tearDownAppWebCookie() {
 
 		Preferences.ofCookie(this).setAppCookies(appHost, appCookies);
 
-		CookieManager.getInstance().removeAllCookie();
+		if (CookieManager.getInstance().hasCookies()) {
+			CookieManager.getInstance().removeAllCookie();
+		}
 	}
 
 	private static final class AppWebClient extends WebViewClient

src/main/java/org/amahi/anywhere/fragment/NavigationFragment.java

@@ -126,6 +126,10 @@ private AccountManager getAccountManager() {
 
 	@Override
 	public void onAccountsUpdated(Account[] accounts) {
+		if (isVisible()) {
+			return;
+		}
+
 		if (getAccounts().isEmpty()) {
 			setUpAccount();
 		}

src/main/java/org/amahi/anywhere/fragment/SettingsFragment.java

@@ -135,9 +135,13 @@ public boolean onPreferenceClick(Preference preference) {
 	}
 
 	private void tearDownAccount() {
-		Account account = getAccounts().get(0);
+		if (!getAccounts().isEmpty()) {
+			Account account = getAccounts().get(0);
 
-		getAccountManager().removeAccount(account, this, null);
+			getAccountManager().removeAccount(account, this, null);
+		} else {
+			tearDownActivity();
+		}
 	}
 
 	private List<Account> getAccounts() {

src/main/java/org/amahi/anywhere/receiver/AudioReceiver.java

@@ -40,11 +40,17 @@ public class AudioReceiver extends BroadcastReceiver
 {
 	@Override
 	public void onReceive(Context context, Intent intent) {
-		if (intent.getAction().equals(AudioManager.ACTION_AUDIO_BECOMING_NOISY)) {
+		if (intent == null) {
+			return;
+		}
+
+		String action = intent.getAction();
+
+		if (AudioManager.ACTION_AUDIO_BECOMING_NOISY.equals(action)) {
 			handleAudioChangeEvent();
 		}
 
-		if (intent.getAction().equals(Intent.ACTION_MEDIA_BUTTON)) {
+		if (Intent.ACTION_MEDIA_BUTTON.equals(action)) {
 			handleAudioControlEvent(intent);
 		}
 	}
@@ -56,6 +62,10 @@ private void handleAudioChangeEvent() {
 	private void handleAudioControlEvent(Intent intent) {
 		KeyEvent event = intent.getParcelableExtra(Intent.EXTRA_KEY_EVENT);
 
+		if (event == null) {
+			return;
+		}
+
 		if (event.getAction() != KeyEvent.ACTION_DOWN) {
 			return;
 		}

src/main/java/org/amahi/anywhere/server/client/ServerClient.java

@@ -222,9 +222,10 @@ public Uri getFileUri(ServerShare share, ServerFile file) {
 	}
 
 	public ServerFileMetadata getFileMetadata(ServerShare share, ServerFile file) {
-        if (share == null || file == null){
+        if ((server == null) || (share == null) || (file == null)){
             return null;
         }
+
 		try {
 			return serverApi.getFileMetadata(server.getSession(), file.getName(), share.getTag());
 		} catch (RetrofitError error) {

src/main/java/org/amahi/anywhere/util/Downloader.java

@@ -48,7 +48,7 @@ public class Downloader extends BroadcastReceiver
 
 	@Inject
 	public Downloader(Context context) {
-		this.context = context;
+		this.context = context.getApplicationContext();
 
 		this.downloadId = Integer.MIN_VALUE;
 	}
@@ -116,7 +116,11 @@ private void finishDownloading() {
 	}
 
 	private void tearDownDownloadReceiver() {
-		context.unregisterReceiver(this);
+		try {
+			context.unregisterReceiver(this);
+		} catch (IllegalArgumentException e) {
+			// False alarm, no need to unregister.
+		}
 	}
 
 	public void finishFileDownloading() {