mirror of
https://github.com/moparisthebest/k-9
synced 2024-11-27 03:32:16 -05:00
Improved handling of object retention on configuration changes
This commit is contained in:
cketti
parent
b05750c245
commit
b146fcb2fd
@ -12,6 +12,7 @@ import java.util.Map;
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import java.util.Set;
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import java.util.concurrent.ConcurrentHashMap;
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import android.app.Activity;
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import android.app.AlertDialog;
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import android.app.Dialog;
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import android.app.ProgressDialog;
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@ -60,6 +61,7 @@ import com.fsck.k9.R;
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import com.fsck.k9.SearchAccount;
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import com.fsck.k9.SearchSpecification;
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import com.fsck.k9.activity.misc.ExtendedAsyncTask;
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import com.fsck.k9.activity.misc.NonConfigurationInstance;
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import com.fsck.k9.activity.setup.AccountSettings;
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import com.fsck.k9.activity.setup.AccountSetupBasics;
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import com.fsck.k9.activity.setup.Prefs;
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@ -107,27 +109,11 @@ public class Accounts extends K9ListActivity implements OnItemClickListener, OnC
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private FontSizes mFontSizes = K9.getFontSizes();
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/**
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* Contains a reference to a {@link ExtendedAsyncTask} while it is running.
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*/
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private ExtendedAsyncTask<Void, Void, Boolean> mAsyncTask;
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/**
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* Contains information about the currently displayed dialog (if available).
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* Contains information about objects that need to be retained on configuration changes.
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*
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* <p>
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* This object is returned from {@link #onRetainNonConfigurationInstance()} if a dialog is
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* being displayed while the activity is being restarted. It is then used by the new activity
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* instance to re-create that dialog.
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* </p>
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* @see #onRetainNonConfigurationInstance()
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*/
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private DialogInfo mDialogInfo;
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/**
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* Reference to the dialog currently being displayed (if available).
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*
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* @see #showDialog(int, String)
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*/
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private AlertDialog mDialog;
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private NonConfigurationInstance mNonConfigurationInstance;
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private static final int ACTIVITY_REQUEST_PICK_SETTINGS_FILE = 1;
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@ -365,18 +351,9 @@ public class Accounts extends K9ListActivity implements OnItemClickListener, OnC
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restoreAccountStats(icicle);
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// Handle activity restarts because of a configuration change (e.g. rotating the screen)
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Object retained = getLastNonConfigurationInstance();
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if (retained != null) {
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// If we displayed a dialog before the configuration change, re-create it here
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if (retained instanceof DialogInfo) {
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DialogInfo dialogInfo = (DialogInfo) retained;
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showDialog(dialogInfo.headerRes, dialogInfo.message);
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}
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// If there's an ExtendedAsyncTask running, update it with the new Activity
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else if (retained instanceof ExtendedAsyncTask) {
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mAsyncTask = (ExtendedAsyncTask) retained;
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mAsyncTask.attach(this);
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}
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mNonConfigurationInstance = (NonConfigurationInstance) getLastNonConfigurationInstance();
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if (mNonConfigurationInstance != null) {
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mNonConfigurationInstance.restore(this);
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}
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}
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@ -435,12 +412,8 @@ public class Accounts extends K9ListActivity implements OnItemClickListener, OnC
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@Override
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public Object onRetainNonConfigurationInstance() {
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Object retain = null;
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if (mDialogInfo != null) {
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retain = mDialogInfo;
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dismissDialog();
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} else if (mAsyncTask != null) {
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retain = mAsyncTask;
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mAsyncTask.detach();
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if (mNonConfigurationInstance != null && mNonConfigurationInstance.retain()) {
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retain = mNonConfigurationInstance;
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}
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return retain;
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}
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@ -924,71 +897,213 @@ public class Accounts extends K9ListActivity implements OnItemClickListener, OnC
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Log.i(K9.LOG_TAG, "onImport importing from URI " + uri.toString());
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mAsyncTask = new ListImportContentsAsyncTask(this, uri, null);
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mAsyncTask.execute();
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ListImportContentsAsyncTask asyncTask = new ListImportContentsAsyncTask(this, uri, null);
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setNonConfigurationInstance(asyncTask);
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asyncTask.execute();
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}
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private void asyncTaskFinished() {
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mAsyncTask = null;
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private void showSimpleDialog(int headerRes, int messageRes, Object... args) {
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SimpleDialog dialog = new SimpleDialog(headerRes, messageRes, args);
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dialog.show(this);
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setNonConfigurationInstance(dialog);
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}
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/**
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* Stores information about a dialog.
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*
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* @see Accounts#showDialog(int, String)
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* @see Accounts#onCreate(Bundle)
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*/
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private static class DialogInfo {
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public final int headerRes;
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private static class SimpleDialog implements NonConfigurationInstance {
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private final int mHeaderRes;
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private final int mMessageRes;
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private Object[] mArguments;
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private Dialog mDialog;
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//TODO: "message" is already localized. This is a problem if the activity is restarted when
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// the system language was changed. We have to recreate the message string in that case.
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public final String message;
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SimpleDialog(int headerRes, int messageRes, Object... args) {
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this.mHeaderRes = headerRes;
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this.mMessageRes = messageRes;
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this.mArguments = args;
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}
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DialogInfo(int headerRes, String message) {
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this.headerRes = headerRes;
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this.message = message;
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@Override
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public void restore(Activity activity) {
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show(activity);
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}
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@Override
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public boolean retain() {
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if (mDialog != null) {
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mDialog.dismiss();
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mDialog = null;
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return true;
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}
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return false;
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}
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public void show(final Activity activity) {
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final String message = activity.getString(mMessageRes, mArguments);
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final AlertDialog.Builder builder = new AlertDialog.Builder(activity);
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builder.setTitle(mHeaderRes);
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builder.setMessage(message);
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builder.setPositiveButton(R.string.okay_action,
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new DialogInterface.OnClickListener() {
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@Override
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public void onClick(DialogInterface dialog, int which) {
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dialog.dismiss();
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destroy();
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}
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});
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mDialog = builder.show();
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}
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private void destroy() {
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mDialog = null;
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mArguments = null;
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}
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}
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/**
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* Show a dialog.
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*
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* @param headerRes
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* The resource ID of the string that is used as title for the dialog box.
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* @param message
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* The message to display.
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*/
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private void showDialog(final int headerRes, final String message) {
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runOnUiThread(new Runnable() {
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@Override
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public void run() {
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// Store information about the dialog so it can be re-created when the activity is
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// restarted due to a configuration change.
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mDialogInfo = new DialogInfo(headerRes, message);
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final AlertDialog.Builder builder = new AlertDialog.Builder(Accounts.this);
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builder.setTitle(headerRes);
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builder.setMessage(message);
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builder.setPositiveButton(R.string.okay_action,
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new DialogInterface.OnClickListener() {
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@Override
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public void onClick(DialogInterface dialog, int which) {
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dismissDialog();
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}
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});
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mDialog = builder.show();
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}
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});
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private void showImportSelectionDialog(ImportContents importContents, Uri uri,
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String encryptionKey) {
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ImportSelectionDialog dialog = new ImportSelectionDialog(importContents, uri, encryptionKey);
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dialog.show(this);
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setNonConfigurationInstance(dialog);
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}
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/**
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* Dismiss the dialog that was created using {@link #showDialog(int, String)}.
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*/
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private void dismissDialog() {
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mDialog.dismiss();
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mDialogInfo = null;
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mDialog = null;
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private static class ImportSelectionDialog implements NonConfigurationInstance {
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private ImportContents mImportContents;
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private Uri mUri;
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private String mEncryptionKey;
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private Dialog mDialog;
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private ListView mImportSelectionView;
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private SparseBooleanArray mSelection;
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ImportSelectionDialog(ImportContents importContents, Uri uri, String encryptionKey) {
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mImportContents = importContents;
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mUri = uri;
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mEncryptionKey = encryptionKey;
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}
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@Override
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public void restore(Activity activity) {
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show((Accounts) activity, mSelection);
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}
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@Override
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public boolean retain() {
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if (mDialog != null) {
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// Save the selection state of each list item
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mSelection = mImportSelectionView.getCheckedItemPositions();
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mImportSelectionView = null;
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mDialog.dismiss();
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mDialog = null;
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return true;
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}
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return false;
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}
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public void show(Accounts activity) {
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show(activity, null);
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}
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public void show(final Accounts activity, SparseBooleanArray selection) {
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final ListView importSelectionView = new ListView(activity);
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mImportSelectionView = importSelectionView;
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List<String> contents = new ArrayList<String>();
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if (mImportContents.globalSettings) {
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//TODO: read from resources
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contents.add("Global settings");
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}
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for (AccountDescription account : mImportContents.accounts) {
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contents.add(account.name);
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}
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importSelectionView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
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importSelectionView.setAdapter(new ArrayAdapter<String>(activity,
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android.R.layout.simple_list_item_checked, contents));
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importSelectionView.setOnItemSelectedListener(new OnItemSelectedListener() {
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@Override
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public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) {
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CheckedTextView ctv = (CheckedTextView)view;
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ctv.setChecked(!ctv.isChecked());
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}
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@Override
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public void onNothingSelected(AdapterView<?> arg0) { /* Do nothing */ }
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});
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if (selection != null) {
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for (int i = 0, end = contents.size(); i < end; i++) {
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importSelectionView.setItemChecked(i, selection.get(i));
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}
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}
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//TODO: listview header: "Please select the settings you wish to import"
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//TODO: listview footer: "Select all" / "Select none" buttons?
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//TODO: listview footer: "Overwrite existing accounts?" checkbox
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final AlertDialog.Builder builder = new AlertDialog.Builder(activity);
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//TODO: read from resources
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builder.setTitle("Import selection");
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builder.setView(importSelectionView);
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builder.setInverseBackgroundForced(true);
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builder.setPositiveButton(R.string.okay_action,
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new DialogInterface.OnClickListener() {
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@Override
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public void onClick(DialogInterface dialog, int which) {
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ListAdapter adapter = importSelectionView.getAdapter();
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int count = adapter.getCount();
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SparseBooleanArray pos = importSelectionView.getCheckedItemPositions();
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boolean includeGlobals = mImportContents.globalSettings ? pos.get(0) : false;
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List<String> accountUuids = new ArrayList<String>();
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int start = mImportContents.globalSettings ? 1 : 0;
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for (int i = start; i < count; i++) {
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if (pos.get(i)) {
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accountUuids.add(mImportContents.accounts.get(i-start).uuid);
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}
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}
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/*
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* TODO: Think some more about this. Overwriting could change the store
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* type. This requires some additional code in order to work smoothly
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* while the app is running.
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*/
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boolean overwrite = false;
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dialog.dismiss();
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destroy();
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ImportAsyncTask importAsyncTask = new ImportAsyncTask(activity,
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includeGlobals, accountUuids, overwrite, mEncryptionKey, mUri);
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activity.setNonConfigurationInstance(importAsyncTask);
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importAsyncTask.execute();
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}
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});
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builder.setNegativeButton(R.string.cancel_action,
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new DialogInterface.OnClickListener() {
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@Override
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public void onClick(DialogInterface dialog, int which) {
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dialog.dismiss();
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destroy();
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}
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});
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mDialog = builder.show();
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}
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private void destroy() {
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mDialog = null;
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mImportContents = null;
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mUri = null;
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mEncryptionKey = null;
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mSelection = null;
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mImportSelectionView = null;
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}
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}
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private void setNonConfigurationInstance(NonConfigurationInstance inst) {
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mNonConfigurationInstance = inst;
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}
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class AccountsAdapter extends ArrayAdapter<BaseAccount> {
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@ -1213,8 +1328,9 @@ public class Accounts extends K9ListActivity implements OnItemClickListener, OnC
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})
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.show();
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*/
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mAsyncTask = new ExportAsyncTask(this, includeGlobals, accountUuids, null);
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mAsyncTask.execute();
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ExportAsyncTask asyncTask = new ExportAsyncTask(this, includeGlobals, accountUuids, null);
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setNonConfigurationInstance(asyncTask);
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asyncTask.execute();
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}
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/**
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@ -1259,17 +1375,17 @@ public class Accounts extends K9ListActivity implements OnItemClickListener, OnC
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Accounts activity = (Accounts) mActivity;
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// Let the activity know that the background task is complete
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activity.asyncTaskFinished();
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activity.setNonConfigurationInstance(null);
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removeProgressDialog();
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if (success) {
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activity.showDialog(R.string.settings_export_success_header,
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mContext.getString(R.string.settings_export_success, mFileName));
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activity.showSimpleDialog(R.string.settings_export_success_header,
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R.string.settings_export_success, mFileName);
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} else {
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//TODO: make the exporter return an error code; translate that error code to a localized string here
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activity.showDialog(R.string.settings_export_failed_header,
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mContext.getString(R.string.settings_export_failure, "Something went wrong"));
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activity.showSimpleDialog(R.string.settings_export_failed_header,
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R.string.settings_export_failure, "Something went wrong");
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}
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}
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}
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@ -1330,7 +1446,7 @@ public class Accounts extends K9ListActivity implements OnItemClickListener, OnC
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Accounts activity = (Accounts) mActivity;
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// Let the activity know that the background task is complete
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activity.asyncTaskFinished();
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activity.setNonConfigurationInstance(null);
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removeProgressDialog();
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@ -1339,14 +1455,14 @@ public class Accounts extends K9ListActivity implements OnItemClickListener, OnC
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//TODO: display names of imported accounts (name from file *and* possibly new name)
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activity.showDialog(R.string.settings_import_success_header,
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activity.showSimpleDialog(R.string.settings_import_success_header,
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//FIXME: use correct file name
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mContext.getString(R.string.settings_import_success, imported, "filename"));
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R.string.settings_import_success, imported, "filename");
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activity.refresh();
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} else {
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//TODO: make the importer return an error code; translate that error code to a localized string here
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activity.showDialog(R.string.settings_import_failed_header,
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mContext.getString(R.string.settings_import_failure, "unknown", "Something went wrong"));
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activity.showSimpleDialog(R.string.settings_import_failed_header,
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R.string.settings_import_failure, "unknown", "Something went wrong");
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}
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}
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}
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@ -1399,91 +1515,17 @@ public class Accounts extends K9ListActivity implements OnItemClickListener, OnC
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Accounts activity = (Accounts) mActivity;
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// Let the activity know that the background task is complete
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activity.asyncTaskFinished();
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activity.setNonConfigurationInstance(null);
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removeProgressDialog();
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if (success) {
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showImportSelectionDialog();
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activity.showImportSelectionDialog(mImportContents, mUri, mEncryptionKey);
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} else {
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//TODO: make the importer return an error code; translate that error code to a localized string here
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activity.showDialog(R.string.settings_import_failed_header,
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mContext.getString(R.string.settings_import_failure, "unknown", "Something went wrong"));
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activity.showSimpleDialog(R.string.settings_import_failed_header,
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R.string.settings_import_failure, "unknown", "Something went wrong");
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}
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}
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//TODO: we need to be able to re-create this dialog after a configuration change
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private void showImportSelectionDialog() {
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final ListView importSelectionView = new ListView(mActivity);
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List<String> contents = new ArrayList<String>();
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if (mImportContents.globalSettings) {
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contents.add("Global settings");
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}
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for (AccountDescription account : mImportContents.accounts) {
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contents.add(account.name);
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}
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importSelectionView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
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importSelectionView.setAdapter(new ArrayAdapter<String>(mActivity, android.R.layout.simple_list_item_checked, contents));
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importSelectionView.setOnItemSelectedListener(new OnItemSelectedListener() {
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@Override
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public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) {
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CheckedTextView ctv = (CheckedTextView)view;
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ctv.setChecked(!ctv.isChecked());
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}
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@Override
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public void onNothingSelected(AdapterView<?> arg0) { /* Do nothing */ }
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});
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//TODO: listview header: "Please select the settings you wish to import"
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//TODO: listview footer: "Select all" / "Select none" buttons?
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//TODO: listview footer: "Overwrite existing accounts?" checkbox
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final AlertDialog.Builder builder = new AlertDialog.Builder(mActivity);
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builder.setTitle("Import selection");
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builder.setView(importSelectionView);
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builder.setInverseBackgroundForced(true);
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builder.setPositiveButton(R.string.okay_action,
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new DialogInterface.OnClickListener() {
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@Override
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public void onClick(DialogInterface dialog, int which) {
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ListAdapter adapter = importSelectionView.getAdapter();
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int count = adapter.getCount();
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SparseBooleanArray pos = importSelectionView.getCheckedItemPositions();
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boolean includeGlobals = mImportContents.globalSettings ? pos.get(0) : false;
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List<String> accountUuids = new ArrayList<String>();
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int start = mImportContents.globalSettings ? 1 : 0;
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for (int i = start; i < count; i++) {
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if (pos.get(i)) {
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accountUuids.add(mImportContents.accounts.get(i-start).uuid);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* TODO: Think some more about this. Overwriting could change the store
|
||||
* type. This requires some additional code in order to work smoothly
|
||||
* while the app is running.
|
||||
*/
|
||||
boolean overwrite = false;
|
||||
|
||||
dialog.dismiss();
|
||||
Accounts activity = (Accounts) mActivity;
|
||||
ImportAsyncTask importAsyncTask = new ImportAsyncTask(activity,
|
||||
includeGlobals, accountUuids, overwrite, mEncryptionKey, mUri);
|
||||
activity.mAsyncTask = importAsyncTask;
|
||||
importAsyncTask.execute();
|
||||
}
|
||||
});
|
||||
builder.setNegativeButton(R.string.cancel_action,
|
||||
new DialogInterface.OnClickListener() {
|
||||
@Override
|
||||
public void onClick(DialogInterface dialog, int which) {
|
||||
dialog.dismiss();
|
||||
}
|
||||
});
|
||||
builder.show();
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
@ -24,11 +24,11 @@ import android.os.AsyncTask;
|
||||
* @param <Result>
|
||||
* see {@link AsyncTask}
|
||||
*
|
||||
* @see #attach(Activity)
|
||||
* @see #detach()
|
||||
* @see #restore(Activity)
|
||||
* @see #retain()
|
||||
*/
|
||||
public abstract class ExtendedAsyncTask<Params, Progress, Result>
|
||||
extends AsyncTask<Params, Progress, Result> {
|
||||
extends AsyncTask<Params, Progress, Result> implements NonConfigurationInstance {
|
||||
protected Activity mActivity;
|
||||
protected Context mContext;
|
||||
protected ProgressDialog mProgressDialog;
|
||||
@ -49,7 +49,8 @@ public abstract class ExtendedAsyncTask<Params, Progress, Result>
|
||||
* @param activity
|
||||
* The new {@code Activity} instance. Never {@code null}.
|
||||
*/
|
||||
public void attach(Activity activity) {
|
||||
@Override
|
||||
public void restore(Activity activity) {
|
||||
mActivity = activity;
|
||||
showProgressDialog();
|
||||
}
|
||||
@ -64,11 +65,20 @@ public abstract class ExtendedAsyncTask<Params, Progress, Result>
|
||||
* being destroyed.
|
||||
* </p>
|
||||
*
|
||||
* @return {@code true} if this instance should be retained; {@code false} otherwise.
|
||||
*
|
||||
* @see Activity#onRetainNonConfigurationInstance()
|
||||
*/
|
||||
public void detach() {
|
||||
removeProgressDialog();
|
||||
@Override
|
||||
public boolean retain() {
|
||||
boolean retain = false;
|
||||
if (mProgressDialog != null) {
|
||||
removeProgressDialog();
|
||||
retain = true;
|
||||
}
|
||||
mActivity = null;
|
||||
|
||||
return retain;
|
||||
}
|
||||
|
||||
/**
|
||||
|
||||
38
src/com/fsck/k9/activity/misc/NonConfigurationInstance.java
Normal file
38
src/com/fsck/k9/activity/misc/NonConfigurationInstance.java
Normal file
@ -0,0 +1,38 @@
|
||||
package com.fsck.k9.activity.misc;
|
||||
|
||||
import android.app.Activity;
|
||||
|
||||
|
||||
public interface NonConfigurationInstance {
|
||||
/**
|
||||
* Decide whether to retain this {@code NonConfigurationInstance} and clean up resources if
|
||||
* necessary.
|
||||
*
|
||||
* <p>
|
||||
* This needs to be called when the current activity is being destroyed during an activity
|
||||
* restart due to a configuration change.<br>
|
||||
* Implementations should make sure that references to the {@code Activity} instance that is
|
||||
* about to be destroyed are cleared to avoid memory leaks. This includes all UI elements that
|
||||
* are bound to an activity (e.g. dialogs). They can be re-created in
|
||||
* {@link #restore(Activity)}.
|
||||
* </p>
|
||||
*
|
||||
* @return {@code true} if this instance should be retained; {@code false} otherwise.
|
||||
*
|
||||
* @see Activity#onRetainNonConfigurationInstance()
|
||||
*/
|
||||
public boolean retain();
|
||||
|
||||
/**
|
||||
* Connect this retained {@code NonConfigurationInstance} to the new {@link Activity} instance
|
||||
* after the activity was restarted due to a configuration change.
|
||||
*
|
||||
* <p>
|
||||
* This also creates a new progress dialog that is bound to the new activity.
|
||||
* </p>
|
||||
*
|
||||
* @param activity
|
||||
* The new {@code Activity} instance. Never {@code null}.
|
||||
*/
|
||||
public void restore(Activity activity);
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user