我正在尝试开发一个简单的QR扫描仪应用程序。我已经按照教程here进行了操作，但它似乎无法正常工作。
以下是我的 build.gradle（应用级别）
apply plugin: 'com.android.application'
android {
compileSdkVersion 24
buildToolsVersion "24.0.3"
defaultConfig {
applicationId "qrcode.auro.com.qrreaderexample"
minSdkVersion 16
targetSdkVersion 24
versionCode 1
versionName "1.0"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
exclude group: 'com.android.support', module: 'support-annotations'
})
compile 'com.android.support:appcompat-v7:24.2.1'
compile 'com.google.android.gms:play-services-vision:9.6.1'
compile fileTree(dir: 'libs', include: ['*.jar'])
testCompile 'junit:junit:4.12'
}
的AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="qrcode.auro.com.qrreaderexample">
<uses-permission android:name="android.permission.CAMERA"/>
<uses-feature
android:name="android.hardware.camera2"
android:required="true"/>
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<meta-data android:name="com.google.android.gms.vision.DEPENDENCIES" android:value="barcode"/>
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
activity_main.xml中
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="qrcode.auro.com.qrreaderexample.MainActivity">
<TextView
android:id="@+id/barcode_text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_alignParentTop="true"
android:text="READING BARCODE...."/>
<SurfaceView
android:id="@+id/surface_view"
android:layout_width="300dp"
android:layout_height="300dp"
android:layout_centerInParent="true"/>
<Button
android:id="@+id/scanner_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="SCAN"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"/>
</RelativeLayout>
MainActivity.java
package qrcode.auro.com.qrreaderexample;
import android.Manifest;
import android.content.pm.PackageManager;
import android.graphics.Camera;
import android.support.v4.app.ActivityCompat;
import android.support.v4.util.SparseArrayCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.SparseArray;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import com.google.android.gms.vision.CameraSource;
import com.google.android.gms.vision.Detector;
import com.google.android.gms.vision.barcode.Barcode;
import com.google.android.gms.vision.barcode.BarcodeDetector;
import java.io.IOException;
public class MainActivity extends AppCompatActivity {
private SurfaceView surfaceView;
private Button button;
private TextView barcodeText;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
surfaceView = (SurfaceView) findViewById(R.id.surface_view);
button = (Button) findViewById(R.id.scanner_button);
barcodeText = (TextView) findViewById(R.id.barcode_text);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
createCameraSource();
}
});
}
private void createCameraSource() {
BarcodeDetector barcodeDetector = new BarcodeDetector.Builder(this).build();
final CameraSource cameraSource = new CameraSource.Builder(this, barcodeDetector)
.setAutoFocusEnabled(true)
.setRequestedPreviewSize(500, 500)
.build();
surfaceView.getHolder().addCallback(new SurfaceHolder.Callback() {
@Override
public void surfaceCreated(SurfaceHolder holder) {
if (ActivityCompat.checkSelfPermission(getApplicationContext(), Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
return;
}
try {
cameraSource.start(surfaceView.getHolder());
} catch (IOException e) {
e.printStackTrace();
}
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
cameraSource.stop();
}
});
barcodeDetector.setProcessor(new Detector.Processor<Barcode>() {
@Override
public void release() {
}
@Override
public void receiveDetections(Detector.Detections<Barcode> detections) {
final SparseArray<Barcode> barcodes = detections.getDetectedItems();
if (barcodes.size() > 0) {
barcodeText.setText(barcodes.valueAt(0).displayValue);
} else
barcodeText.setText("NO BARCODES FOUND!!!!");
}
});
}
}
我在这里有一个按钮（R.id.scanner_button）应该打开相机并开始阅读代码，但它没有。
每次点击按钮，我都会在 logcat 中获得以下内容：
10-21 13:16:55.370 25722-25722/qrcode.auro.com.qrreaderexample W/DynamiteModule: Local module descriptor class for com.google.android.gms.vision.dynamite not found.
10-21 13:16:55.373 25722-25722/qrcode.auro.com.qrreaderexample I/DynamiteModule: Considering local module com.google.android.gms.vision.dynamite:0 and remote module com.google.android.gms.vision.dynamite:8
10-21 13:16:55.374 25722-25722/qrcode.auro.com.qrreaderexample I/DynamiteModule: Selected remote version of com.google.android.gms.vision.dynamite, version >= 8
我在这里缺少什么？