src/com/android/contacts/common/vcard/ExportVCardActivity.java

/*
 * Copyright (C) 2009 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.android.contacts.common.vcard;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.content.ComponentName;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.ServiceConnection;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.os.IBinder;
import android.provider.OpenableColumns;
import android.text.BidiFormatter;
import android.text.TextDirectionHeuristics;
import android.util.Log;

import com.android.contacts.common.R;
import com.android.contacts.common.activity.RequestImportVCardPermissionsActivity;

/**
 * Shows a dialog confirming the export and asks actual vCard export to {@link VCardService}
 *
 * This Activity first connects to VCardService and ask an available file name and shows it to
 * a user. After the user's confirmation, it send export request with the file name, assuming the
 * file name is not reserved yet.
 */
public class ExportVCardActivity extends Activity implements ServiceConnection,
        DialogInterface.OnClickListener, DialogInterface.OnCancelListener {
    private static final String LOG_TAG = "VCardExport";
    private static final boolean DEBUG = VCardService.DEBUG;
    private static final int REQUEST_CREATE_DOCUMENT = 100;

    /**
     * True when this Activity is connected to {@link VCardService}.
     *
     * Should be touched inside synchronized block.
     */
    private boolean mConnected;

    /**
     * True when users need to do something and this Activity should not disconnect from
     * VCardService. False when all necessary procedures are done (including sending export request)
     * or there's some error occured.
     */
    private volatile boolean mProcessOngoing = true;

    private VCardService mService;
    private static final BidiFormatter mBidiFormatter = BidiFormatter.getInstance();

    // String for storing error reason temporarily.
    private String mErrorReason;

    @Override
    protected void onCreate(Bundle bundle) {
        super.onCreate(bundle);

        if (RequestImportVCardPermissionsActivity.startPermissionActivity(this,
                /* isCallerSelf */ false)) {
            return;
        }

        connectVCardService();
    }

    private void connectVCardService() {
        final String callingActivity = getIntent().getExtras()
                .getString(VCardCommonArguments.ARG_CALLING_ACTIVITY);
        Intent intent = new Intent(this, VCardService.class);
        intent.putExtra(VCardCommonArguments.ARG_CALLING_ACTIVITY, callingActivity);

        if (startService(intent) == null) {
            Log.e(LOG_TAG, "Failed to start vCard service");
            mErrorReason = getString(R.string.fail_reason_unknown);
            showDialog(R.id.dialog_fail_to_export_with_reason);
            return;
        }

        if (!bindService(intent, this, Context.BIND_AUTO_CREATE)) {
            Log.e(LOG_TAG, "Failed to connect to vCard service.");
            mErrorReason = getString(R.string.fail_reason_unknown);
            showDialog(R.id.dialog_fail_to_export_with_reason);
        }
        // Continued to onServiceConnected()
    }

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == REQUEST_CREATE_DOCUMENT) {
            if (resultCode == Activity.RESULT_OK && data != null && data.getData() != null) {
                final Uri mTargetFileName = data.getData();
                if (DEBUG) Log.d(LOG_TAG, "exporting to " + mTargetFileName);
                final ExportRequest request = new ExportRequest(mTargetFileName);
                // The connection object will call finish().
                mService.handleExportRequest(request, new NotificationImportExportListener(
                        ExportVCardActivity.this));
            } else if (DEBUG) {
                Log.d(LOG_TAG, "create document cancelled or no data returned");
            }
            unbindAndFinish();
        }
    }

    @Override
    public synchronized void onServiceConnected(ComponentName name, IBinder binder) {
        if (DEBUG) Log.d(LOG_TAG, "connected to service, requesting a destination file name");
        mConnected = true;
        mService = ((VCardService.MyBinder) binder).getService();

        // Have the user choose where vcards will be exported to
        final Intent intent = new Intent(Intent.ACTION_CREATE_DOCUMENT);
        intent.addCategory(Intent.CATEGORY_OPENABLE);
        intent.setType(VCardService.X_VCARD_MIME_TYPE);
        intent.putExtra(Intent.EXTRA_TITLE, mBidiFormatter.unicodeWrap(
                getString(R.string.exporting_vcard_filename), TextDirectionHeuristics.LTR));
        startActivityForResult(intent, REQUEST_CREATE_DOCUMENT);
    }

    // Use synchronized since we don't want to call unbindAndFinish() just after this call.
    @Override
    public synchronized void onServiceDisconnected(ComponentName name) {
        if (DEBUG) Log.d(LOG_TAG, "onServiceDisconnected()");
        mService = null;
        mConnected = false;
        if (mProcessOngoing) {
            // Unexpected disconnect event.
            Log.w(LOG_TAG, "Disconnected from service during the process ongoing.");
            mErrorReason = getString(R.string.fail_reason_unknown);
            showDialog(R.id.dialog_fail_to_export_with_reason);
        }
    }

    @Override
    protected Dialog onCreateDialog(int id, Bundle bundle) {
        switch (id) {
            case R.string.fail_reason_too_many_vcard: {
                mProcessOngoing = false;
                return new AlertDialog.Builder(this)
                        .setTitle(R.string.exporting_contact_failed_title)
                        .setMessage(getString(R.string.exporting_contact_failed_message,
                                getString(R.string.fail_reason_too_many_vcard)))
                        .setPositiveButton(android.R.string.ok, this)
                        .create();
            }
            case R.id.dialog_fail_to_export_with_reason: {
                mProcessOngoing = false;
                return new AlertDialog.Builder(this)
                        .setTitle(R.string.exporting_contact_failed_title)
                        .setMessage(getString(R.string.exporting_contact_failed_message,
                                mErrorReason != null ? mErrorReason :
                                        getString(R.string.fail_reason_unknown)))
                        .setPositiveButton(android.R.string.ok, this)
                        .setOnCancelListener(this)
                        .create();
            }
        }
        return super.onCreateDialog(id, bundle);
    }

    @Override
    protected void onPrepareDialog(int id, Dialog dialog, Bundle args) {
        if (id == R.id.dialog_fail_to_export_with_reason) {
            ((AlertDialog)dialog).setMessage(mErrorReason);
        } else {
            super.onPrepareDialog(id, dialog, args);
        }
    }

    @Override
    public void onClick(DialogInterface dialog, int which) {
        if (DEBUG) Log.d(LOG_TAG, "ExportVCardActivity#onClick() is called");
        unbindAndFinish();
    }

    @Override
    public void onCancel(DialogInterface dialog) {
        if (DEBUG) Log.d(LOG_TAG, "ExportVCardActivity#onCancel() is called");
        mProcessOngoing = false;
        unbindAndFinish();
    }

    @Override
    public void unbindService(ServiceConnection conn) {
        mProcessOngoing = false;
        super.unbindService(conn);
    }

    /**
     * Returns the display name for the given openable Uri or null if it could not be resolved. */
    static String getOpenableUriDisplayName(Context context, Uri uri) {
        if (uri == null) return null;
        final Cursor cursor = context.getContentResolver().query(uri, null, null, null, null);
        try {
            if (cursor != null && cursor.moveToFirst()) {
                return cursor.getString(cursor.getColumnIndex(OpenableColumns.DISPLAY_NAME));
            }
        } finally {
            if (cursor != null)  {
                cursor.close();
            }
        }
        return null;
    }

    private synchronized void unbindAndFinish() {
        if (mConnected) {
            unbindService(this);
            mConnected = false;
        }
        finish();
    }
}