mirror of
https://github.com/moparisthebest/k-9
synced 2024-11-05 17:15:05 -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;
|
||||
import java.util.Set;
|
||||
import java.util.concurrent.ConcurrentHashMap;
|
||||
|
||||
import android.app.Activity;
|
||||
import android.app.AlertDialog;
|
||||
import android.app.Dialog;
|
||||
import android.app.ProgressDialog;
|
||||
@ -60,6 +61,7 @@ import com.fsck.k9.R;
|
||||
import com.fsck.k9.SearchAccount;
|
||||
import com.fsck.k9.SearchSpecification;
|
||||
import com.fsck.k9.activity.misc.ExtendedAsyncTask;
|
||||
import com.fsck.k9.activity.misc.NonConfigurationInstance;
|
||||
import com.fsck.k9.activity.setup.AccountSettings;
|
||||
import com.fsck.k9.activity.setup.AccountSetupBasics;
|
||||
import com.fsck.k9.activity.setup.Prefs;
|
||||
@ -107,27 +109,11 @@ public class Accounts extends K9ListActivity implements OnItemClickListener, OnC
|
||||
private FontSizes mFontSizes = K9.getFontSizes();
|
||||
|
||||
/**
|
||||
* Contains a reference to a {@link ExtendedAsyncTask} while it is running.
|
||||
*/
|
||||
private ExtendedAsyncTask<Void, Void, Boolean> mAsyncTask;
|
||||
|
||||
/**
|
||||
* Contains information about the currently displayed dialog (if available).
|
||||
* Contains information about objects that need to be retained on configuration changes.
|
||||
*
|
||||
* <p>
|
||||
* This object is returned from {@link #onRetainNonConfigurationInstance()} if a dialog is
|
||||
* being displayed while the activity is being restarted. It is then used by the new activity
|
||||
* instance to re-create that dialog.
|
||||
* </p>
|
||||
* @see #onRetainNonConfigurationInstance()
|
||||
*/
|
||||
private DialogInfo mDialogInfo;
|
||||
|
||||
/**
|
||||
* Reference to the dialog currently being displayed (if available).
|
||||
*
|
||||
* @see #showDialog(int, String)
|
||||
*/
|
||||
private AlertDialog mDialog;
|
||||
private NonConfigurationInstance mNonConfigurationInstance;
|
||||
|
||||
|
||||
private static final int ACTIVITY_REQUEST_PICK_SETTINGS_FILE = 1;
|
||||
@ -365,18 +351,9 @@ public class Accounts extends K9ListActivity implements OnItemClickListener, OnC
|
||||
restoreAccountStats(icicle);
|
||||
|
||||
// Handle activity restarts because of a configuration change (e.g. rotating the screen)
|
||||
Object retained = getLastNonConfigurationInstance();
|
||||
if (retained != null) {
|
||||
// If we displayed a dialog before the configuration change, re-create it here
|
||||
if (retained instanceof DialogInfo) {
|
||||
DialogInfo dialogInfo = (DialogInfo) retained;
|
||||
showDialog(dialogInfo.headerRes, dialogInfo.message);
|
||||
}
|
||||
// If there's an ExtendedAsyncTask running, update it with the new Activity
|
||||
else if (retained instanceof ExtendedAsyncTask) {
|
||||
mAsyncTask = (ExtendedAsyncTask) retained;
|
||||
mAsyncTask.attach(this);
|
||||
}
|
||||
mNonConfigurationInstance = (NonConfigurationInstance) getLastNonConfigurationInstance();
|
||||
if (mNonConfigurationInstance != null) {
|
||||
mNonConfigurationInstance.restore(this);
|
||||
}
|
||||
}
|
||||
|
||||
@ -435,12 +412,8 @@ public class Accounts extends K9ListActivity implements OnItemClickListener, OnC
|
||||
@Override
|
||||
public Object onRetainNonConfigurationInstance() {
|
||||
Object retain = null;
|
||||
if (mDialogInfo != null) {
|
||||
retain = mDialogInfo;
|
||||
dismissDialog();
|
||||
} else if (mAsyncTask != null) {
|
||||
retain = mAsyncTask;
|
||||
mAsyncTask.detach();
|
||||
if (mNonConfigurationInstance != null && mNonConfigurationInstance.retain()) {
|
||||
retain = mNonConfigurationInstance;
|
||||
}
|
||||
return retain;
|
||||
}
|
||||
@ -924,71 +897,213 @@ public class Accounts extends K9ListActivity implements OnItemClickListener, OnC
|
||||
|
||||
Log.i(K9.LOG_TAG, "onImport importing from URI " + uri.toString());
|
||||
|
||||
mAsyncTask = new ListImportContentsAsyncTask(this, uri, null);
|
||||
mAsyncTask.execute();
|
||||
ListImportContentsAsyncTask asyncTask = new ListImportContentsAsyncTask(this, uri, null);
|
||||
setNonConfigurationInstance(asyncTask);
|
||||
asyncTask.execute();
|
||||
}
|
||||
|
||||
private void asyncTaskFinished() {
|
||||
mAsyncTask = null;
|
||||
|
||||
private void showSimpleDialog(int headerRes, int messageRes, Object... args) {
|
||||
SimpleDialog dialog = new SimpleDialog(headerRes, messageRes, args);
|
||||
dialog.show(this);
|
||||
setNonConfigurationInstance(dialog);
|
||||
}
|
||||
|
||||
/**
|
||||
* Stores information about a dialog.
|
||||
*
|
||||
* @see Accounts#showDialog(int, String)
|
||||
* @see Accounts#onCreate(Bundle)
|
||||
*/
|
||||
private static class DialogInfo {
|
||||
public final int headerRes;
|
||||
private static class SimpleDialog implements NonConfigurationInstance {
|
||||
private final int mHeaderRes;
|
||||
private final int mMessageRes;
|
||||
private Object[] mArguments;
|
||||
private Dialog mDialog;
|
||||
|
||||
//TODO: "message" is already localized. This is a problem if the activity is restarted when
|
||||
// the system language was changed. We have to recreate the message string in that case.
|
||||
public final String message;
|
||||
SimpleDialog(int headerRes, int messageRes, Object... args) {
|
||||
this.mHeaderRes = headerRes;
|
||||
this.mMessageRes = messageRes;
|
||||
this.mArguments = args;
|
||||
}
|
||||
|
||||
DialogInfo(int headerRes, String message) {
|
||||
this.headerRes = headerRes;
|
||||
this.message = message;
|
||||
@Override
|
||||
public void restore(Activity activity) {
|
||||
show(activity);
|
||||
}
|
||||
|
||||
@Override
|
||||
public boolean retain() {
|
||||
if (mDialog != null) {
|
||||
mDialog.dismiss();
|
||||
mDialog = null;
|
||||
return true;
|
||||
}
|
||||
return false;
|
||||
}
|
||||
|
||||
public void show(final Activity activity) {
|
||||
final String message = activity.getString(mMessageRes, mArguments);
|
||||
|
||||
final AlertDialog.Builder builder = new AlertDialog.Builder(activity);
|
||||
builder.setTitle(mHeaderRes);
|
||||
builder.setMessage(message);
|
||||
builder.setPositiveButton(R.string.okay_action,
|
||||
new DialogInterface.OnClickListener() {
|
||||
@Override
|
||||
public void onClick(DialogInterface dialog, int which) {
|
||||
dialog.dismiss();
|
||||
destroy();
|
||||
}
|
||||
});
|
||||
mDialog = builder.show();
|
||||
}
|
||||
|
||||
private void destroy() {
|
||||
mDialog = null;
|
||||
mArguments = null;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Show a dialog.
|
||||
*
|
||||
* @param headerRes
|
||||
* The resource ID of the string that is used as title for the dialog box.
|
||||
* @param message
|
||||
* The message to display.
|
||||
*/
|
||||
private void showDialog(final int headerRes, final String message) {
|
||||
runOnUiThread(new Runnable() {
|
||||
@Override
|
||||
public void run() {
|
||||
// Store information about the dialog so it can be re-created when the activity is
|
||||
// restarted due to a configuration change.
|
||||
mDialogInfo = new DialogInfo(headerRes, message);
|
||||
|
||||
final AlertDialog.Builder builder = new AlertDialog.Builder(Accounts.this);
|
||||
builder.setTitle(headerRes);
|
||||
builder.setMessage(message);
|
||||
builder.setPositiveButton(R.string.okay_action,
|
||||
new DialogInterface.OnClickListener() {
|
||||
@Override
|
||||
public void onClick(DialogInterface dialog, int which) {
|
||||
dismissDialog();
|
||||
}
|
||||
});
|
||||
mDialog = builder.show();
|
||||
}
|
||||
});
|
||||
private void showImportSelectionDialog(ImportContents importContents, Uri uri,
|
||||
String encryptionKey) {
|
||||
ImportSelectionDialog dialog = new ImportSelectionDialog(importContents, uri, encryptionKey);
|
||||
dialog.show(this);
|
||||
setNonConfigurationInstance(dialog);
|
||||
}
|
||||
|
||||
/**
|
||||
* Dismiss the dialog that was created using {@link #showDialog(int, String)}.
|
||||
*/
|
||||
private void dismissDialog() {
|
||||
mDialog.dismiss();
|
||||
mDialogInfo = null;
|
||||
mDialog = null;
|
||||
private static class ImportSelectionDialog implements NonConfigurationInstance {
|
||||
private ImportContents mImportContents;
|
||||
private Uri mUri;
|
||||
private String mEncryptionKey;
|
||||
private Dialog mDialog;
|
||||
private ListView mImportSelectionView;
|
||||
private SparseBooleanArray mSelection;
|
||||
|
||||
|
||||
ImportSelectionDialog(ImportContents importContents, Uri uri, String encryptionKey) {
|
||||
mImportContents = importContents;
|
||||
mUri = uri;
|
||||
mEncryptionKey = encryptionKey;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void restore(Activity activity) {
|
||||
show((Accounts) activity, mSelection);
|
||||
}
|
||||
|
||||
@Override
|
||||
public boolean retain() {
|
||||
if (mDialog != null) {
|
||||
// Save the selection state of each list item
|
||||
mSelection = mImportSelectionView.getCheckedItemPositions();
|
||||
mImportSelectionView = null;
|
||||
|
||||
mDialog.dismiss();
|
||||
mDialog = null;
|
||||
return true;
|
||||
}
|
||||
return false;
|
||||
}
|
||||
|
||||
public void show(Accounts activity) {
|
||||
show(activity, null);
|
||||
}
|
||||
|
||||
public void show(final Accounts activity, SparseBooleanArray selection) {
|
||||
final ListView importSelectionView = new ListView(activity);
|
||||
mImportSelectionView = importSelectionView;
|
||||
List<String> contents = new ArrayList<String>();
|
||||
|
||||
if (mImportContents.globalSettings) {
|
||||
//TODO: read from resources
|
||||
contents.add("Global settings");
|
||||
}
|
||||
|
||||
for (AccountDescription account : mImportContents.accounts) {
|
||||
contents.add(account.name);
|
||||
}
|
||||
|
||||
importSelectionView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
|
||||
importSelectionView.setAdapter(new ArrayAdapter<String>(activity,
|
||||
android.R.layout.simple_list_item_checked, contents));
|
||||
importSelectionView.setOnItemSelectedListener(new OnItemSelectedListener() {
|
||||
@Override
|
||||
public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) {
|
||||
CheckedTextView ctv = (CheckedTextView)view;
|
||||
ctv.setChecked(!ctv.isChecked());
|
||||
}
|
||||
|
||||
@Override
|
||||
public void onNothingSelected(AdapterView<?> arg0) { /* Do nothing */ }
|
||||
});
|
||||
|
||||
if (selection != null) {
|
||||
for (int i = 0, end = contents.size(); i < end; i++) {
|
||||
importSelectionView.setItemChecked(i, selection.get(i));
|
||||
}
|
||||
}
|
||||
|
||||
//TODO: listview header: "Please select the settings you wish to import"
|
||||
//TODO: listview footer: "Select all" / "Select none" buttons?
|
||||
//TODO: listview footer: "Overwrite existing accounts?" checkbox
|
||||
|
||||
final AlertDialog.Builder builder = new AlertDialog.Builder(activity);
|
||||
//TODO: read from resources
|
||||
builder.setTitle("Import selection");
|
||||
builder.setView(importSelectionView);
|
||||
builder.setInverseBackgroundForced(true);
|
||||
builder.setPositiveButton(R.string.okay_action,
|
||||
new DialogInterface.OnClickListener() {
|
||||
|
||||
@Override
|
||||
public void onClick(DialogInterface dialog, int which) {
|
||||
ListAdapter adapter = importSelectionView.getAdapter();
|
||||
int count = adapter.getCount();
|
||||
SparseBooleanArray pos = importSelectionView.getCheckedItemPositions();
|
||||
|
||||
boolean includeGlobals = mImportContents.globalSettings ? pos.get(0) : false;
|
||||
List<String> accountUuids = new ArrayList<String>();
|
||||
int start = mImportContents.globalSettings ? 1 : 0;
|
||||
for (int i = start; i < count; i++) {
|
||||
if (pos.get(i)) {
|
||||
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();
|
||||
destroy();
|
||||
|
||||
ImportAsyncTask importAsyncTask = new ImportAsyncTask(activity,
|
||||
includeGlobals, accountUuids, overwrite, mEncryptionKey, mUri);
|
||||
activity.setNonConfigurationInstance(importAsyncTask);
|
||||
importAsyncTask.execute();
|
||||
}
|
||||
});
|
||||
builder.setNegativeButton(R.string.cancel_action,
|
||||
new DialogInterface.OnClickListener() {
|
||||
@Override
|
||||
public void onClick(DialogInterface dialog, int which) {
|
||||
dialog.dismiss();
|
||||
destroy();
|
||||
}
|
||||
});
|
||||
mDialog = builder.show();
|
||||
}
|
||||
|
||||
private void destroy() {
|
||||
mDialog = null;
|
||||
mImportContents = null;
|
||||
mUri = null;
|
||||
mEncryptionKey = null;
|
||||
mSelection = null;
|
||||
mImportSelectionView = null;
|
||||
}
|
||||
}
|
||||
|
||||
private void setNonConfigurationInstance(NonConfigurationInstance inst) {
|
||||
mNonConfigurationInstance = inst;
|
||||
}
|
||||
|
||||
class AccountsAdapter extends ArrayAdapter<BaseAccount> {
|
||||
@ -1213,8 +1328,9 @@ public class Accounts extends K9ListActivity implements OnItemClickListener, OnC
|
||||
})
|
||||
.show();
|
||||
*/
|
||||
mAsyncTask = new ExportAsyncTask(this, includeGlobals, accountUuids, null);
|
||||
mAsyncTask.execute();
|
||||
ExportAsyncTask asyncTask = new ExportAsyncTask(this, includeGlobals, accountUuids, null);
|
||||
setNonConfigurationInstance(asyncTask);
|
||||
asyncTask.execute();
|
||||
}
|
||||
|
||||
/**
|
||||
@ -1259,17 +1375,17 @@ public class Accounts extends K9ListActivity implements OnItemClickListener, OnC
|
||||
Accounts activity = (Accounts) mActivity;
|
||||
|
||||
// Let the activity know that the background task is complete
|
||||
activity.asyncTaskFinished();
|
||||
activity.setNonConfigurationInstance(null);
|
||||
|
||||
removeProgressDialog();
|
||||
|
||||
if (success) {
|
||||
activity.showDialog(R.string.settings_export_success_header,
|
||||
mContext.getString(R.string.settings_export_success, mFileName));
|
||||
activity.showSimpleDialog(R.string.settings_export_success_header,
|
||||
R.string.settings_export_success, mFileName);
|
||||
} else {
|
||||
//TODO: make the exporter return an error code; translate that error code to a localized string here
|
||||
activity.showDialog(R.string.settings_export_failed_header,
|
||||
mContext.getString(R.string.settings_export_failure, "Something went wrong"));
|
||||
activity.showSimpleDialog(R.string.settings_export_failed_header,
|
||||
R.string.settings_export_failure, "Something went wrong");
|
||||
}
|
||||
}
|
||||
}
|
||||
@ -1330,7 +1446,7 @@ public class Accounts extends K9ListActivity implements OnItemClickListener, OnC
|
||||
Accounts activity = (Accounts) mActivity;
|
||||
|
||||
// Let the activity know that the background task is complete
|
||||
activity.asyncTaskFinished();
|
||||
activity.setNonConfigurationInstance(null);
|
||||
|
||||
removeProgressDialog();
|
||||
|
||||
@ -1339,14 +1455,14 @@ public class Accounts extends K9ListActivity implements OnItemClickListener, OnC
|
||||
|
||||
//TODO: display names of imported accounts (name from file *and* possibly new name)
|
||||
|
||||
activity.showDialog(R.string.settings_import_success_header,
|
||||
activity.showSimpleDialog(R.string.settings_import_success_header,
|
||||
//FIXME: use correct file name
|
||||
mContext.getString(R.string.settings_import_success, imported, "filename"));
|
||||
R.string.settings_import_success, imported, "filename");
|
||||
activity.refresh();
|
||||
} else {
|
||||
//TODO: make the importer return an error code; translate that error code to a localized string here
|
||||
activity.showDialog(R.string.settings_import_failed_header,
|
||||
mContext.getString(R.string.settings_import_failure, "unknown", "Something went wrong"));
|
||||
activity.showSimpleDialog(R.string.settings_import_failed_header,
|
||||
R.string.settings_import_failure, "unknown", "Something went wrong");
|
||||
}
|
||||
}
|
||||
}
|
||||
@ -1399,91 +1515,17 @@ public class Accounts extends K9ListActivity implements OnItemClickListener, OnC
|
||||
Accounts activity = (Accounts) mActivity;
|
||||
|
||||
// Let the activity know that the background task is complete
|
||||
activity.asyncTaskFinished();
|
||||
activity.setNonConfigurationInstance(null);
|
||||
|
||||
removeProgressDialog();
|
||||
|
||||
if (success) {
|
||||
showImportSelectionDialog();
|
||||
activity.showImportSelectionDialog(mImportContents, mUri, mEncryptionKey);
|
||||
} else {
|
||||
//TODO: make the importer return an error code; translate that error code to a localized string here
|
||||
activity.showDialog(R.string.settings_import_failed_header,
|
||||
mContext.getString(R.string.settings_import_failure, "unknown", "Something went wrong"));
|
||||
activity.showSimpleDialog(R.string.settings_import_failed_header,
|
||||
R.string.settings_import_failure, "unknown", "Something went wrong");
|
||||
}
|
||||
}
|
||||
|
||||
//TODO: we need to be able to re-create this dialog after a configuration change
|
||||
private void showImportSelectionDialog() {
|
||||
final ListView importSelectionView = new ListView(mActivity);
|
||||
List<String> contents = new ArrayList<String>();
|
||||
if (mImportContents.globalSettings) {
|
||||
contents.add("Global settings");
|
||||
}
|
||||
for (AccountDescription account : mImportContents.accounts) {
|
||||
contents.add(account.name);
|
||||
}
|
||||
importSelectionView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
|
||||
importSelectionView.setAdapter(new ArrayAdapter<String>(mActivity, android.R.layout.simple_list_item_checked, contents));
|
||||
importSelectionView.setOnItemSelectedListener(new OnItemSelectedListener() {
|
||||
@Override
|
||||
public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) {
|
||||
CheckedTextView ctv = (CheckedTextView)view;
|
||||
ctv.setChecked(!ctv.isChecked());
|
||||
}
|
||||
|
||||
@Override
|
||||
public void onNothingSelected(AdapterView<?> arg0) { /* Do nothing */ }
|
||||
});
|
||||
|
||||
//TODO: listview header: "Please select the settings you wish to import"
|
||||
//TODO: listview footer: "Select all" / "Select none" buttons?
|
||||
//TODO: listview footer: "Overwrite existing accounts?" checkbox
|
||||
|
||||
final AlertDialog.Builder builder = new AlertDialog.Builder(mActivity);
|
||||
builder.setTitle("Import selection");
|
||||
builder.setView(importSelectionView);
|
||||
builder.setInverseBackgroundForced(true);
|
||||
builder.setPositiveButton(R.string.okay_action,
|
||||
new DialogInterface.OnClickListener() {
|
||||
|
||||
@Override
|
||||
public void onClick(DialogInterface dialog, int which) {
|
||||
ListAdapter adapter = importSelectionView.getAdapter();
|
||||
int count = adapter.getCount();
|
||||
SparseBooleanArray pos = importSelectionView.getCheckedItemPositions();
|
||||
|
||||
boolean includeGlobals = mImportContents.globalSettings ? pos.get(0) : false;
|
||||
List<String> accountUuids = new ArrayList<String>();
|
||||
int start = mImportContents.globalSettings ? 1 : 0;
|
||||
for (int i = start; i < count; i++) {
|
||||
if (pos.get(i)) {
|
||||
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