在Android開發讀取條碼(Bar Code、QR Code)最容易的方法就是使用ZXing, 在Android平板或手機上也必須安裝ZXing條碼掃描程式。
接著在專案中必須增加兩個Class, 分別是IntentIntegrator.java與IntentResult.java。
IntentIntegrator.java
/**
* 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 tw.com.envimac.dieselreceiver;
import tw.com.envimac.dieselreceiver.IntentIntegrator;
import tw.com.envimac.dieselreceiver.IntentResult;
import android.app.AlertDialog;
import android.app.Activity;
import android.content.ActivityNotFoundException;
import android.content.DialogInterface;
import android.content.Intent;
import android.net.Uri;
/**
* A utility class which helps ease integration with Barcode Scanner via {@link 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.
*
* Initiating a barcode scan
*
* Integration is essentially as easy as calling {@link #initiateScan(Activity)} and waiting
* for the result in your app.
*
* It does require that the Barcode Scanner application is installed. The
* {@link #initiateScan(Activity)} method will prompt the user to download the application, if needed.
*
* There are a few steps to using this integration. First, your {@link Activity} must implement
* the method {@link Activity#onActivityResult(int, int, Intent)} and include a line of code like this:
*
* {@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
* ...
* }
* }
*
* This is where you will handle a scan result.
* Second, just call this in response to a user action somewhere to begin the scan process:
*
* {@code IntentIntegrator.initiateScan(yourActivity);}
*
* You can use {@link #initiateScan(Activity, CharSequence, CharSequence, CharSequence, CharSequence)} or
* {@link #initiateScan(Activity, int, int, int, int)} to customize the download prompt with
* different text labels.
*
* Note that {@link #initiateScan(Activity)} returns an {@link 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 Activity#onPause()}
* method.
*
* Sharing text via barcode
*
* To share text, encoded as a QR Code on-screen, similarly, see {@link #shareText(Activity, CharSequence)}.
*
* Some code, particularly download integration, was contributed from the Anobiit application.
*
* @author Sean Owen
* @author Fred Lin
* @author Isaac Potoczny-Jones
* @author Brad Drehmer
*/
public final class IntentIntegrator {
public static final int REQUEST_CODE = 0x0ba7c0de; // get it?
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";
// supported barcode formats
public static final String PRODUCT_CODE_TYPES = "UPC_A,UPC_E,EAN_8,EAN_13";
public static final String ONE_D_CODE_TYPES = PRODUCT_CODE_TYPES + ",CODE_39,CODE_93,CODE_128";
public static final String QR_CODE_TYPES = "QR_CODE";
public static final String ALL_CODE_TYPES = null;
private IntentIntegrator() {
}
/**
* See {@link #initiateScan(Activity, CharSequence, CharSequence, CharSequence, CharSequence)} --
* same, but uses default English labels.
*/
public static AlertDialog initiateScan(Activity activity) {
return initiateScan(activity, DEFAULT_TITLE, DEFAULT_MESSAGE, DEFAULT_YES, DEFAULT_NO);
}
/**
* See {@link #initiateScan(Activity, CharSequence, CharSequence, CharSequence, CharSequence)} --
* same, but takes string IDs which refer
* to the {@link Activity}'s resource bundle entries.
*/
public static AlertDialog initiateScan(Activity activity,
int stringTitle,
int stringMessage,
int stringButtonYes,
int stringButtonNo) {
return initiateScan(activity,
activity.getString(stringTitle),
activity.getString(stringMessage),
activity.getString(stringButtonYes),
activity.getString(stringButtonNo));
}
/**
* See {@link #initiateScan(Activity, CharSequence, CharSequence, CharSequence, CharSequence, CharSequence)} --
* same, but scans for all supported barcode types.
* @param stringTitle title of dialog prompting user to download Barcode Scanner
* @param stringMessage text of dialog prompting user to download Barcode Scanner
* @param stringButtonYes text of button user clicks when agreeing to download
* Barcode Scanner (e.g. "Yes")
* @param stringButtonNo text of button user clicks when declining to download
* Barcode Scanner (e.g. "No")
* @return an {@link AlertDialog} if the user was prompted to download the app,
* null otherwise
*/
public static AlertDialog initiateScan(Activity activity,
CharSequence stringTitle,
CharSequence stringMessage,
CharSequence stringButtonYes,
CharSequence stringButtonNo) {
return initiateScan(activity,
stringTitle,
stringMessage,
stringButtonYes,
stringButtonNo,
ALL_CODE_TYPES);
}
/**
* Invokes scanning.
*
* @param stringTitle title of dialog prompting user to download Barcode Scanner
* @param stringMessage text of dialog prompting user to download Barcode Scanner
* @param stringButtonYes text of button user clicks when agreeing to download
* Barcode Scanner (e.g. "Yes")
* @param stringButtonNo text of button user clicks when declining to download
* Barcode Scanner (e.g. "No")
* @param stringDesiredBarcodeFormats a comma separated list of codes you would
* like to scan for.
* @return an {@link AlertDialog} if the user was prompted to download the app,
* null otherwise
* @throws InterruptedException if timeout expires before a scan completes
*/
public static AlertDialog initiateScan(Activity activity,
CharSequence stringTitle,
CharSequence stringMessage,
CharSequence stringButtonYes,
CharSequence stringButtonNo,
CharSequence stringDesiredBarcodeFormats) {
Intent intentScan = new Intent("com.google.zxing.client.android.SCAN");
intentScan.addCategory(Intent.CATEGORY_DEFAULT);
// check which types of codes to scan for
if (stringDesiredBarcodeFormats != null) {
// set the desired barcode types
intentScan.putExtra("SCAN_FORMATS", stringDesiredBarcodeFormats);
}
try {
activity.startActivityForResult(intentScan, REQUEST_CODE);
return null;
} catch (ActivityNotFoundException e) {
return showDownloadDialog(activity, stringTitle, stringMessage, stringButtonYes, stringButtonNo);
}
}
private static AlertDialog showDownloadDialog(final Activity activity,
CharSequence stringTitle,
CharSequence stringMessage,
CharSequence stringButtonYes,
CharSequence stringButtonNo) {
AlertDialog.Builder downloadDialog = new AlertDialog.Builder(activity);
downloadDialog.setTitle(stringTitle);
downloadDialog.setMessage(stringMessage);
downloadDialog.setPositiveButton(stringButtonYes, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialogInterface, int i) {
Uri uri = Uri.parse("market://search?q=pname:com.google.zxing.client.android");
Intent intent = new Intent(Intent.ACTION_VIEW, uri);
activity.startActivity(intent);
}
});
downloadDialog.setNegativeButton(stringButtonNo, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialogInterface, int i) {}
});
return downloadDialog.show();
}
/**
* Call this from your {@link Activity}'s
* {@link Activity#onActivityResult(int, int, Intent)} method.
*
* @return null if the event handled here was not related to {@link IntentIntegrator}, 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");
return new IntentResult(contents, formatName);
} else {
return new IntentResult(null, null);
}
}
return null;
}
/**
* See {@link #shareText(Activity, CharSequence, CharSequence, CharSequence, CharSequence, CharSequence)} --
* same, but uses default English labels.
*/
public static void shareText(Activity activity, CharSequence text) {
shareText(activity, text, DEFAULT_TITLE, DEFAULT_MESSAGE, DEFAULT_YES, DEFAULT_NO);
}
/**
* See {@link #shareText(Activity, CharSequence, CharSequence, CharSequence, CharSequence, CharSequence)} --
* same, but takes string IDs which refer to the {@link Activity}'s resource bundle entries.
*/
public static void shareText(Activity activity,
CharSequence text,
int stringTitle,
int stringMessage,
int stringButtonYes,
int stringButtonNo) {
shareText(activity,
text,
activity.getString(stringTitle),
activity.getString(stringMessage),
activity.getString(stringButtonYes),
activity.getString(stringButtonNo));
}
/**
* 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 stringTitle title of dialog prompting user to download Barcode Scanner
* @param stringMessage text of dialog prompting user to download Barcode Scanner
* @param stringButtonYes text of button user clicks when agreeing to download
* Barcode Scanner (e.g. "Yes")
* @param stringButtonNo text of button user clicks when declining to download
* Barcode Scanner (e.g. "No")
*/
public static void shareText(Activity activity,
CharSequence text,
CharSequence stringTitle,
CharSequence stringMessage,
CharSequence stringButtonYes,
CharSequence stringButtonNo) {
Intent intent = new Intent();
intent.setAction("com.google.zxing.client.android.ENCODE");
intent.putExtra("ENCODE_TYPE", "TEXT_TYPE");
intent.putExtra("ENCODE_DATA", text);
try {
activity.startActivity(intent);
} catch (ActivityNotFoundException e) {
showDownloadDialog(activity, stringTitle, stringMessage, stringButtonYes, stringButtonNo);
}
}
}
IntentResult.java
/**
* 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 tw.com.envimac.dieselreceiver;
import tw.com.envimac.dieselreceiver.IntentIntegrator;
/**
* Encapsulates the result of a barcode scan invoked through {@link IntentIntegrator}.
*
* @author Sean Owen
*/
public final class IntentResult {
private final String contents;
private final String formatName;
IntentResult(String contents, String formatName) {
this.contents = contents;
this.formatName = formatName;
}
/**
* @return raw content of barcode
*/
public String getContents() {
return contents;
}
/**
* @return name of format, like "QR_CODE", "UPC_A". See BarcodeFormat
for more format names.
*/
public String getFormatName() {
return formatName;
}
}
在頁面增加一個Button啟動條碼掃描的功能與顯示條碼內容。
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.scan_bar_code);
intent = this.getIntent();
final TextView tv1 = (TextView) ScanBarCodeActivity.this.findViewById(R.id.tvFormat);
tv1.setText("");
// 掃描條碼
final Button b1 = (Button) this.findViewById(R.id.btnScan);
b1.setOnClickListener(new Button.OnClickListener() {
public void onClick(View v) {
IntentIntegrator.initiateScan(ScanBarCodeActivity.this,
"提示",
"ZXing Barcode Scanner is not installed, download?",
"Yes", "No",
"PRODUCT_MODE");
}
});
}
public void onActivityResult(int requestCode, int resultCode, Intent intent) {
switch (requestCode) {
case IntentIntegrator.REQUEST_CODE:
if (resultCode == Activity.RESULT_OK) {
IntentResult intentResult =
IntentIntegrator.parseActivityResult(requestCode, resultCode, intent);
if (intentResult != null) {
String contents = intentResult.getContents();
String format = intentResult.getFormatName();
// 顯示條碼格式
final TextView tv1 = (TextView) ScanBarCodeActivity.this.findViewById(R.id.tvFormat);
tv1.setText(format);
// 顯示條碼內容
final EditText tv2 = (EditText) this.findViewById(R.id.edtCarNo);
tv2.setText(contents);
}
}
}
}
參考來源:
http://stackoverflow.com/questions/12074316/how-to-create-for-intentintegrator-in-android-with-zxing