Java 通过意图捕捉照片

Java 通过意图捕捉照片,java,android,Java,Android,我正在尝试制作“拍照”教程,在完成所有步骤之后,我仍然有一个错误。更确切地说,在我拍完照片后,它会显示信息“相机已停止”。我添加了一个按钮,可以在单击时打开相机,并添加了一个imageView来显示照片。我正在尝试在三星Galaxy S7(Android 8.0.0,API 26)上部署该应用程序 这是setOnClickListener: protected void onCreate(Bundle savedInstanceState) { super.onCreate(s

我正在尝试制作“拍照”教程,在完成所有步骤之后,我仍然有一个错误。更确切地说,在我拍完照片后,它会显示信息“相机已停止”。我添加了一个按钮,可以在单击时打开相机,并添加了一个imageView来显示照片。我正在尝试在三星Galaxy S7(Android 8.0.0,API 26)上部署该应用程序

这是setOnClickListener:

 protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Button button = (Button) findViewById((R.id.button));
        ImageView imageView = (ImageView)findViewById(R.id.imageView);

        if (ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
            button.setEnabled(false);
            ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA, Manifest.permission.WRITE_EXTERNAL_STORAGE}, 0);
        }

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                dispatchTakePictureIntent();

            }
        });
    }
这是摄像机的拍摄方法:

private void dispatchTakePictureIntent() {
        Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        takePictureIntent.addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
        // Ensure that there's a camera activity to handle the intent
        if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
            // Create the File where the photo should go
            File imageView = null;
            try {
                imageView = createImageFile();
            } catch (IOException ex) {
                // Error occurred while creating the File
                ex.printStackTrace();
            }
            // Continue only if the File was successfully created
            if (imageView != null) {
                Uri photoURI = FileProvider.getUriForFile(this,
                        "com.example.camapp.fileprovider",
                        imageView);
                takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, photoURI);
                startActivityForResult(takePictureIntent, REQUEST_TAKE_PHOTO);
            }
        }
    }
文件路径:

<paths xmlns:android="http://schemas.android.com/apk/res/android">
        <external-path
            name="my_images"
            path="Android/data/com.example.camapp/files/Pictures" />
</paths>

我想制作一个打开相机的按钮,拍摄一张照片并将其保存在gallery或其他指定目录中,因为我将对该照片进行一些图像处理。我尝试了yt上的几乎所有教程,我真的很难找到解决此问题的方法。我感谢您提供的任何解决方案或建议。谢谢您的支持时间

如果您的应用程序要求相机单击图片,则应询问相机权限

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.app">

<uses-permission android:name="android.permission.CAMERA"/>
<!-- other permissions go here -->
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

<application ...>
    ...
</application>
还可以在清单文件中定义文件提供程序

 <provider
 android:name="android.support.v4.content.FileProvider"
 android:authorities="com.yourPackageName.fileprovider"
 android:exported="false"
 android:grantUriPermissions="true">
<meta-data
    android:name="android.support.FILE_PROVIDER_PATHS"
    android:resource="@xml/file_list"></meta-data>
</provider> 


您是否在清单文件中添加了摄像头权限
以及存储权限?正如@RakhiDhavale所建议的,您可能需要更多权限,否则我认为您应该在OnActivityResult()末尾将调用移动到galleryAddPic()确保您的文件存在并包含您的图片。请发布stacktrace@JohnJoe我添加了stacktrace。谢谢你的建议!好的,我在AndroidManifest中添加了“android.permission.CAMERA”权限,现在我单击按钮后,它会显示消息“CAMERA has stopped”,而不启动摄像头。我还在OnActivityResult()的末尾添加了galleryAddPic()。有可能是activity_main.xml中的错误吗?您是否要求用户在拍照之前,单击按钮授予相机和存储权限?如果您是新手,并且在实施过程中遇到问题,请参考此链接请求权限。请参考此教程链接谢谢您的教程!我将再次尝试从那里执行步骤。现在我有权限,但现在我从一开始就遇到了相同的问题。我拍照后,它会显示消息“摄像头已停止”
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<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.app">

<uses-permission android:name="android.permission.CAMERA"/>
<!-- other permissions go here -->
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

<application ...>
    ...
</application>
if (ContextCompat.checkSelfPermission(YourActivityName.this,
    Manifest.permission.CAMERA)
    != PackageManager.PERMISSION_GRANTED) {

    ActivityCompat.requestPermissions(thisActivity,
            new String[]{Manifest.permission.CAMERA, Manifest.permission.WRITE_EXTERNAL_STORAGE},
            YOUR_PERMISSIONS_REQUEST_CODE);

    // YOUR_PERMISSIONS_REQUEST_CODE is an
    // app-defined int constant. The callback method gets the
    // result of the request.

} else {
// Permission has already been granted
}
 <provider
 android:name="android.support.v4.content.FileProvider"
 android:authorities="com.yourPackageName.fileprovider"
 android:exported="false"
 android:grantUriPermissions="true">
<meta-data
    android:name="android.support.FILE_PROVIDER_PATHS"
    android:resource="@xml/file_list"></meta-data>
</provider>