java - 无法实例化以下类： - com.wonderkiln.camerakit.CameraView
问题描述
我正在使用 0.13.1 CameraKit 依赖项，它给出了以下异常。我已经尝试了几乎所有可能的方法。无法将此依赖项更改为最新的 1.0.0 版本，因为那样我将不得不编辑整个代码并更改它，因为他们在新版本中更改了很多内容，我尝试更改它但无法更改整个代码和所有必需的部分。
CameraKit 无法实例化并给出 NUllPointerException：
java.lang.NullPointerException
at android.hardware.Camera.getCameraInfo(Camera.java:295)
at com.wonderkiln.camerakit.Camera1.frontCameraOnly(Camera1.java:648)
at com.wonderkiln.camerakit.CameraView.<init>(CameraView.java:140)
at com.wonderkiln.camerakit.CameraView.<init>(CameraView.java:99)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
at org.jetbrains.android.uipreview.ViewLoader.createNewInstance(ViewLoader.java:404)
at org.jetbrains.android.uipreview.ViewLoader.loadClass(ViewLoader.java:187)
at org.jetbrains.android.uipreview.ViewLoader.loadView(ViewLoader.java:145)
at com.android.tools.idea.rendering.LayoutlibCallbackImpl.loadView(LayoutlibCallbackImpl.java:309)
at android.view.BridgeInflater.loadCustomView(BridgeInflater.java:417)
at android.view.BridgeInflater.loadCustomView(BridgeInflater.java:428)
at android.view.BridgeInflater.createViewFromTag(BridgeInflater.java:332)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:961)
at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:1123)
at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:72)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:1097)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:1084)
at android.view.LayoutInflater.inflate(LayoutInflater.java:682)
at android.view.LayoutInflater.inflate(LayoutInflater.java:501)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.inflate(RenderSessionImpl.java:328)
at com.android.layoutlib.bridge.Bridge.createSession(Bridge.java:396)
at com.android.tools.idea.layoutlib.LayoutLibrary.createSession(LayoutLibrary.java:209)
at com.android.tools.idea.rendering.RenderTask.createRenderSession(RenderTask.java:608)
at com.android.tools.idea.rendering.RenderTask.lambda$inflate$6(RenderTask.java:734)
at java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1590)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
这是我的 XML 文件
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<com.wonderkiln.camerakit.CameraView
android:id="@+id/camera_View"
android:layout_width="match_parent"
android:layout_height="689dp"
android:adjustViewBounds="true"
/>
<com.waqad.facedetectionmodule.Helper.GraphicOverlay
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/graphic_overlay"
android:layout_above="@id/detectFace"/>
<Button
android:id="@+id/detectFace"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_below="@id/camera_View"
android:text="@string/detect_face_btnText"
android:background="@color/colorPrimary"
android:textColor="@color/common_google_signin_btn_text_dark_default"/>
</RelativeLayout>
这是 MainActivity.java 类
package com.waqad.facedetectionmodule;
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import dmax.dialog.SpotsDialog;
import android.app.AlertDialog;
import android.graphics.Bitmap;
import android.graphics.Rect;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;
import com.google.android.gms.tasks.OnFailureListener;
import com.google.android.gms.tasks.OnSuccessListener;
import com.google.firebase.ml.vision.FirebaseVision;
import com.google.firebase.ml.vision.common.FirebaseVisionImage;
import com.google.firebase.ml.vision.face.FirebaseVisionFace;
import com.google.firebase.ml.vision.face.FirebaseVisionFaceDetector;
import com.google.firebase.ml.vision.face.FirebaseVisionFaceDetectorOptions;
import com.waqad.facedetectionmodule.Helper.GraphicOverlay;
import com.waqad.facedetectionmodule.Helper.RectOverlay;
import com.wonderkiln.camerakit.CameraKitError;
import com.wonderkiln.camerakit.CameraKitEvent;
import com.wonderkiln.camerakit.CameraKitEventListener;
import com.wonderkiln.camerakit.CameraKitImage;
import com.wonderkiln.camerakit.CameraKitVideo;
import com.wonderkiln.camerakit.CameraView;
import java.util.List;
public class MainActivity extends AppCompatActivity {
private Button faceDetectButton;
private GraphicOverlay graphicOverlay;
private CameraView cameraView;
AlertDialog alertDialog;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
faceDetectButton = findViewById(R.id.detectFace);
graphicOverlay = findViewById(R.id.graphic_overlay);
cameraView = findViewById(R.id.camera_View);
alertDialog = new SpotsDialog.Builder()
.setContext(this)
.setMessage("Please wait, Processing ...")
.setCancelable(false)
.build();
faceDetectButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
cameraView.start();
cameraView.captureImage();
graphicOverlay.clear();
}
});
cameraView.addCameraKitListener(new CameraKitEventListener() {
@Override
public void onEvent(CameraKitEvent cameraKitEvent) {
}
@Override
public void onError(CameraKitError cameraKitError) {
}
@Override
public void onImage(CameraKitImage cameraKitImage) {
alertDialog.show();
Bitmap bitmap =cameraKitImage.getBitmap();
bitmap = Bitmap.createScaledBitmap(bitmap, cameraView.getWidth(), cameraView.getHeight(), false);
cameraView.stop();
processFaceDatection(bitmap);
}
@Override
public void onVideo(CameraKitVideo cameraKitVideo) {
}
});
}
private void processFaceDatection(Bitmap bitmap) {
FirebaseVisionImage firebaseVisionImage = FirebaseVisionImage.fromBitmap(bitmap);
FirebaseVisionFaceDetectorOptions firebaseVisionFaceDetectorOptions =
new FirebaseVisionFaceDetectorOptions.Builder().build();
FirebaseVisionFaceDetector firebaseVisionFaceDetector = FirebaseVision.getInstance()
.getVisionFaceDetector(firebaseVisionFaceDetectorOptions);
firebaseVisionFaceDetector.detectInImage(firebaseVisionImage).addOnSuccessListener(new OnSuccessListener<List<FirebaseVisionFace>>() {
@Override
public void onSuccess(List<FirebaseVisionFace> firebaseVisionFaces) {
getFaceResults(firebaseVisionFaces);
}
}).addOnFailureListener(new OnFailureListener() {
@Override
public void onFailure(@NonNull Exception e) {
Toast.makeText(MainActivity.this,"Error! " + e.getMessage(),Toast.LENGTH_SHORT)
.show();
}
});
}
private void getFaceResults(List<FirebaseVisionFace> firebaseVisionFaces) {
int counter=0;
for (FirebaseVisionFace face : firebaseVisionFaces){
Rect rect = face.getBoundingBox();
RectOverlay rectOverlay = new RectOverlay(graphicOverlay, rect);
graphicOverlay.add(rectOverlay);
counter += 1;
}
alertDialog.dismiss();
}
@Override
protected void onResume() {
super.onResume();
cameraView.start();
}
@Override
protected void onPause() {
super.onPause();
cameraView.stop();
}
}
我的应用程序级别（build.gradle）
apply plugin: 'com.android.application'
apply plugin: 'com.google.gms.google-services'
android {
compileSdkVersion 28
defaultConfig {
applicationId "com.waqad.facedetectionmodule"
minSdkVersion 16
targetSdkVersion 28
versionCode 1
versionName "1.0"
testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation 'androidx.appcompat:appcompat:1.1.0'
implementation 'com.wonderkiln:camerakit:0.13.1'
implementation 'com.google.firebase:firebase-analytics:17.3.0'
implementation 'com.github.d-max:spots-dialog:1.1@aar'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
implementation 'com.google.firebase:firebase-ml-vision:24.0.1'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'androidx.test.ext:junit:1.1.1'
androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
}
[enter image description here][1]
解决方案
这不是应用程序中的运行时错误。这是 IDE 中的错误，来自图形布局编辑器。除了避免图形布局编辑器之外，您无能为力。这可能已在较新版本的库中得到修复，但您似乎反对升级，所以......
正在发生的事情是，像这样的自定义小部件CameraView需要一些逻辑来避免在图形布局编辑器 ( isInEditMode()) 中执行任何异常操作，因为 IDE 实际上正在运行真正的小部件代码来呈现预览。CameraView没有那个逻辑，所以它会尝试访问一个不存在的相机。但是，尽管有此投诉，您应该能够运行该项目，并且此特定问题不会影响您的应用程序的运行时行为。
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