Java tutorial
/* * Copyright 2009 ZXing authors * * 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 org.familab.app.supportfiles; import android.app.Activity; import android.app.AlertDialog; import android.content.ActivityNotFoundException; import android.content.DialogInterface; import android.content.Intent; import android.content.pm.PackageManager; import android.content.pm.ResolveInfo; import android.net.Uri; import android.os.Bundle; import android.support.v4.app.Fragment; import android.util.Log; import java.util.Arrays; import java.util.Collection; import java.util.Collections; import java.util.HashMap; import java.util.List; import java.util.Map; /** * <p>A utility class which helps ease integration with Barcode Scanner via {@link android.content.Intent}s. This is a simple * way to invoke barcode scanning and receive the result, without any need to integrate, modify, or learn the * project's source code.</p> * * <h2>Initiating a barcode scan</h2> * * <p>To integrate, create an instance of {@code IntentIntegrator} and call {@link #initiateScan()} and wait * for the result in your app.</p> * * <p>It does require that the Barcode Scanner (or work-alike) application is installed. The * {@link #initiateScan()} method will prompt the user to download the application, if needed.</p> * * <p>There are a few steps to using this integration. First, your {@link android.app.Activity} must implement * the method {@link android.app.Activity#onActivityResult(int, int, android.content.Intent)} and include a line of code like this:</p> * * <pre>{@code * public void onActivityResult(int requestCode, int resultCode, Intent intent) { * IntentResult scanResult = IntentIntegrator.parseActivityResult(requestCode, resultCode, intent); * if (scanResult != null) { * // handle scan result * } * // else continue with any other code you need in the method * ... * } * }</pre> * * <p>This is where you will handle a scan result.</p> * * <p>Second, just call this in response to a user action somewhere to begin the scan process:</p> * * <pre>{@code * IntentIntegrator integrator = new IntentIntegrator(yourActivity); * integrator.initiateScan(); * }</pre> * * <p>Note that {@link #initiateScan()} returns an {@link android.app.AlertDialog} which is non-null if the * user was prompted to download the application. This lets the calling app potentially manage the dialog. * In particular, ideally, the app dismisses the dialog if it's still active in its {@link android.app.Activity#onPause()} * method.</p> * * <p>You can use {@link #setTitle(String)} to customize the title of this download prompt dialog (or, use * {@link #setTitleByID(int)} to set the title by string resource ID.) Likewise, the prompt message, and * yes/no button labels can be changed.</p> * * <p>Finally, you can use {@link #addExtra(String, Object)} to add more parameters to the Intent used * to invoke the scanner. This can be used to set additional options not directly exposed by this * simplified API.</p> * * <p>By default, this will only allow applications that are known to respond to this intent correctly * do so. The apps that are allowed to response can be set with {@link #setTargetApplications(java.util.List)}. * For example, set to {@link #TARGET_BARCODE_SCANNER_ONLY} to only target the Barcode Scanner app itself.</p> * * <h2>Sharing text via barcode</h2> * * <p>To share text, encoded as a QR Code on-screen, similarly, see {@link #shareText(CharSequence)}.</p> * * <p>Some code, particularly download integration, was contributed from the Anobiit application.</p> * * <h2>Enabling experimental barcode formats</h2> * * <p>Some formats are not enabled by default even when scanning with {@link #ALL_CODE_TYPES}, such as * PDF417. Use {@link #initiateScan(java.util.Collection)} with * a collection containing the names of formats to scan for explicitly, like "PDF_417", to use such * formats.</p> * * @author Sean Owen * @author Fred Lin * @author Isaac Potoczny-Jones * @author Brad Drehmer * @author gcstang */ public class IntentIntegrator { public static final int REQUEST_CODE = 0x0000c0de; // Only use bottom 16 bits private static final String TAG = IntentIntegrator.class.getSimpleName(); public static final String DEFAULT_TITLE = "Install Barcode Scanner?"; public static final String DEFAULT_MESSAGE = "This application requires Barcode Scanner. Would you like to install it?"; public static final String DEFAULT_YES = "Yes"; public static final String DEFAULT_NO = "No"; private static final String BS_PACKAGE = "com.google.zxing.client.android"; private static final String BSPLUS_PACKAGE = "com.srowen.bs.android"; // supported barcode formats public static final Collection<String> PRODUCT_CODE_TYPES = list("UPC_A", "UPC_E", "EAN_8", "EAN_13", "RSS_14"); public static final Collection<String> ONE_D_CODE_TYPES = list("UPC_A", "UPC_E", "EAN_8", "EAN_13", "CODE_39", "CODE_93", "CODE_128", "ITF", "RSS_14", "RSS_EXPANDED"); public static final Collection<String> QR_CODE_TYPES = Collections.singleton("QR_CODE"); public static final Collection<String> DATA_MATRIX_TYPES = Collections.singleton("DATA_MATRIX"); public static final Collection<String> ALL_CODE_TYPES = null; public static final List<String> TARGET_BARCODE_SCANNER_ONLY = Collections.singletonList(BS_PACKAGE); public static final List<String> TARGET_ALL_KNOWN = list(BS_PACKAGE, // Barcode Scanner BSPLUS_PACKAGE, // Barcode Scanner+ BSPLUS_PACKAGE + ".simple" // Barcode Scanner+ Simple // What else supports this intent? ); private final Fragment activity; private String title; private String message; private String buttonYes; private String buttonNo; private List<String> targetApplications; private final Map<String, Object> moreExtras; public IntentIntegrator(Fragment activity) { this.activity = activity; title = DEFAULT_TITLE; message = DEFAULT_MESSAGE; buttonYes = DEFAULT_YES; buttonNo = DEFAULT_NO; targetApplications = TARGET_ALL_KNOWN; moreExtras = new HashMap<String, Object>(3); } public String getTitle() { return title; } public void setTitle(String title) { this.title = title; } public void setTitleByID(int titleID) { title = activity.getString(titleID); } public String getMessage() { return message; } public void setMessage(String message) { this.message = message; } public void setMessageByID(int messageID) { message = activity.getString(messageID); } public String getButtonYes() { return buttonYes; } public void setButtonYes(String buttonYes) { this.buttonYes = buttonYes; } public void setButtonYesByID(int buttonYesID) { buttonYes = activity.getString(buttonYesID); } public String getButtonNo() { return buttonNo; } public void setButtonNo(String buttonNo) { this.buttonNo = buttonNo; } public void setButtonNoByID(int buttonNoID) { buttonNo = activity.getString(buttonNoID); } public Collection<String> getTargetApplications() { return targetApplications; } public final void setTargetApplications(List<String> targetApplications) { if (targetApplications.isEmpty()) { throw new IllegalArgumentException("No target applications"); } this.targetApplications = targetApplications; } public void setSingleTargetApplication(String targetApplication) { this.targetApplications = Collections.singletonList(targetApplication); } public Map<String, ?> getMoreExtras() { return moreExtras; } public final void addExtra(String key, Object value) { moreExtras.put(key, value); } /** * Initiates a scan for all known barcode types. */ public final AlertDialog initiateScan() { return initiateScan(ALL_CODE_TYPES); } /** * Initiates a scan only for a certain set of barcode types, given as strings corresponding * to their names in ZXing's {@code BarcodeFormat} class like "UPC_A". You can supply constants * like {@link #PRODUCT_CODE_TYPES} for example. * * @return the {@link android.app.AlertDialog} that was shown to the user prompting them to download the app * if a prompt was needed, or null otherwise */ public final AlertDialog initiateScan(Collection<String> desiredBarcodeFormats) { Intent intentScan = new Intent(BS_PACKAGE + ".SCAN"); intentScan.addCategory(Intent.CATEGORY_DEFAULT); // check which types of codes to scan for if (desiredBarcodeFormats != null) { // set the desired barcode types StringBuilder joinedByComma = new StringBuilder(); for (String format : desiredBarcodeFormats) { if (joinedByComma.length() > 0) { joinedByComma.append(','); } joinedByComma.append(format); } intentScan.putExtra("SCAN_FORMATS", joinedByComma.toString()); } String targetAppPackage = findTargetAppPackage(intentScan); if (targetAppPackage == null) { return showDownloadDialog(); } intentScan.setPackage(targetAppPackage); intentScan.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); intentScan.addFlags(Intent.FLAG_ACTIVITY_CLEAR_WHEN_TASK_RESET); attachMoreExtras(intentScan); startActivityForResult(intentScan, REQUEST_CODE); return null; } /** * Start an activity.<br> * This method is defined to allow different methods of activity starting for * newer versions of Android and for compatibility library. * * @param intent Intent to start. * @param code Request code for the activity * @see android.app.Activity#startActivityForResult(android.content.Intent, int) * @see android.app.Fragment#startActivityForResult(android.content.Intent, int) */ protected void startActivityForResult(Intent intent, int code) { activity.startActivityForResult(intent, code); } private String findTargetAppPackage(Intent intent) { PackageManager pm = activity.getActivity().getPackageManager(); List<ResolveInfo> availableApps = pm.queryIntentActivities(intent, PackageManager.MATCH_DEFAULT_ONLY); if (availableApps != null) { for (ResolveInfo availableApp : availableApps) { String packageName = availableApp.activityInfo.packageName; if (targetApplications.contains(packageName)) { return packageName; } } } return null; } private AlertDialog showDownloadDialog() { AlertDialog.Builder downloadDialog = new AlertDialog.Builder(activity.getActivity()); downloadDialog.setTitle(title); downloadDialog.setMessage(message); downloadDialog.setPositiveButton(buttonYes, new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialogInterface, int i) { String packageName = targetApplications.get(0); Uri uri = Uri.parse("market://details?id=" + packageName); Intent intent = new Intent(Intent.ACTION_VIEW, uri); try { activity.startActivity(intent); } catch (ActivityNotFoundException anfe) { // Hmm, market is not installed Log.w(TAG, "Google Play is not installed; cannot install " + packageName); } } }); downloadDialog.setNegativeButton(buttonNo, new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialogInterface, int i) { } }); return downloadDialog.show(); } /** * <p>Call this from your {@link android.app.Activity}'s * {@link android.app.Activity#onActivityResult(int, int, android.content.Intent)} method.</p> * * @return null if the event handled here was not related to this class, or * else an {@link IntentResult} containing the result of the scan. If the user cancelled scanning, * the fields will be null. */ public static IntentResult parseActivityResult(int requestCode, int resultCode, Intent intent) { if (requestCode == REQUEST_CODE) { if (resultCode == Activity.RESULT_OK) { String contents = intent.getStringExtra("SCAN_RESULT"); String formatName = intent.getStringExtra("SCAN_RESULT_FORMAT"); byte[] rawBytes = intent.getByteArrayExtra("SCAN_RESULT_BYTES"); int intentOrientation = intent.getIntExtra("SCAN_RESULT_ORIENTATION", Integer.MIN_VALUE); Integer orientation = intentOrientation == Integer.MIN_VALUE ? null : intentOrientation; String errorCorrectionLevel = intent.getStringExtra("SCAN_RESULT_ERROR_CORRECTION_LEVEL"); return new IntentResult(contents, formatName, rawBytes, orientation, errorCorrectionLevel); } return new IntentResult(); } return null; } /** * Defaults to type "TEXT_TYPE". * @see #shareText(CharSequence, CharSequence) */ public final AlertDialog shareText(CharSequence text) { return shareText(text, "TEXT_TYPE"); } /** * Shares the given text by encoding it as a barcode, such that another user can * scan the text off the screen of the device. * * @param text the text string to encode as a barcode * @param type type of data to encode. See {@code com.google.zxing.client.android.Contents.Type} constants. * @return the {@link android.app.AlertDialog} that was shown to the user prompting them to download the app * if a prompt was needed, or null otherwise */ public final AlertDialog shareText(CharSequence text, CharSequence type) { Intent intent = new Intent(); intent.addCategory(Intent.CATEGORY_DEFAULT); intent.setAction(BS_PACKAGE + ".ENCODE"); intent.putExtra("ENCODE_TYPE", type); intent.putExtra("ENCODE_DATA", text); String targetAppPackage = findTargetAppPackage(intent); if (targetAppPackage == null) { return showDownloadDialog(); } intent.setPackage(targetAppPackage); intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_WHEN_TASK_RESET); attachMoreExtras(intent); activity.startActivity(intent); return null; } private static List<String> list(String... values) { return Collections.unmodifiableList(Arrays.asList(values)); } private void attachMoreExtras(Intent intent) { for (Map.Entry<String, Object> entry : moreExtras.entrySet()) { String key = entry.getKey(); Object value = entry.getValue(); // Kind of hacky if (value instanceof Integer) { intent.putExtra(key, (Integer) value); } else if (value instanceof Long) { intent.putExtra(key, (Long) value); } else if (value instanceof Boolean) { intent.putExtra(key, (Boolean) value); } else if (value instanceof Double) { intent.putExtra(key, (Double) value); } else if (value instanceof Float) { intent.putExtra(key, (Float) value); } else if (value instanceof Bundle) { intent.putExtra(key, (Bundle) value); } else { intent.putExtra(key, value.toString()); } } } }