Android 最简单的调用摄像头

配置是少不了的：

<provider
    android:name="android.support.v4.content.FileProvider"
    android:authorities="你的包名.provider"
    android:exported="false"
    android:grantUriPermissions="true">
    <meta-data
        android:name="android.support.FILE_PROVIDER_PATHS"
        android:resource="@xml/file_paths" />
</provider>

<uses-permission android:name="android.permission.CAMERA"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

res/xml/file_paths.xml

<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <files-path path="Android/data/com.example.package.name/files/Pictures/OriPicture/" name="images" />
    <external-path path="Android/data/com.example.package.name/files/Pictures/OriPicture/" name="images" />
    <external-files-path path="files/Pictures/OriPicture" name="images"/>
    <root-path path="" name="images"/>
    <root-path path="" name="images"/>
    <external-path name="external_files" path="."/>
</paths>

最好在代码里写入权限请求：

int cameraPermission = ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.CAMERA);
if (cameraPermission != PackageManager.PERMISSION_GRANTED) {
    String[] PERMISSIONS_CAMERA_AND_STORAGE = {
           Manifest.permission.READ_EXTERNAL_STORAGE,
           Manifest.permission.WRITE_EXTERNAL_STORAGE,
           Manifest.permission.CAMERA};
    ActivityCompat.requestPermissions(MainActivity.this, PERMISSIONS_CAMERA_AND_STORAGE, 0x001);
 } else {
    openCamera();
}

第一种开启方式：

Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(intent,0x002);

第一种接收方式：

if (resultCode == RESULT_OK) {
    if (requestCode == 0x002) {
        Bundle bundle = data.getExtras();
        Bitmap bitmap = (Bitmap) bundle.get("data");
        iv.setImageBitmap(bitmap);
    }
}

这种出来的图像是缩略图；

第二种开启方式：

private String PhotoPath;
PhotoPath = Environment.getExternalStorageDirectory() + "/Image_" + System.currentTimeMillis() + ".jpg";

Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
Uri photoUri;
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
    photoUri = FileProvider.getUriForFile(this, getPackageName() + ".provider", new File(PhotoPath));
} else {
    photoUri = Uri.fromFile(new File(PhotoPath));
}
intent.putExtra(MediaStore.EXTRA_OUTPUT, photoUri);
startActivityForResult(intent, 0x002);

第二种接收方式：

if (resultCode == RESULT_OK) {
    if (requestCode == 0x002) {
        try {
            FileInputStream fis = new FileInputStream(PhotoPath);
            Bitmap bitmap = BitmapFactory.decodeStream(fis);
            iv.setImageBitmap(bitmap);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
    }
}

使用系统相机：

使用系统Intent：ACTION_IMAGE_CAPTURE

注册Camera功能：

Android摄像头基础