我开始在 android 11 上使用字符串“com.android.camera.action.CROP”进行裁剪的隐式意图。首次安装应用程序时，无法通过此代码解析其活动。
Intent intent = new Intent("com.android.camera.action.CROP");
intent.setType("image/*");
//to check whether there is an cropping app present or not
List<ResolveInfo> resInfoList = getPackageManager().queryIntentActivities(
intent, MATCH_DEFAULT_ONLY);
它不是第一次解决，而是第二次运行，它获得了可以处理意图的活动。
就我而言，我<queries>在 AndroidManifest.xml 中使用以下配置并且它可以工作。
<manifest>
// ...
<queries>
<intent>
<action android:name="com.android.camera.action.CROP" />
<data android:scheme="content"
android:mimeType="image/*"/>
</intent>
</queries>
</manifest>
和resolveActivity：
val intent = Intent("com.android.camera.action.CROP").apply {
type = "image/*"
data = photoUri
}
if (intent.resolveActivity(context.packageManager) != null) {
// grant uri permission here
}
经过一番测试，我发现关键是android:mimeTypequeries必须与typeIntent 中设置的一致。
此代码是从相机应用程序或图库应用程序捕获或导入图像并继续进行裁剪的代码。
MainActivity.java
public class MainActivity extends AppCompatActivity {
public final String APP_TAG = "crop";
public String intermediateName = "1.jpg";
public String resultName = "2.jpg";
Uri intermediateProvider;
Uri resultProvider;
ActivityResultLauncher<Intent> cameraActivityResultLauncher;
ActivityResultLauncher<Intent> galleryActivityResultLauncher;
ActivityResultLauncher<Intent> cropActivityResultLauncher;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button buttonCamera = findViewById(R.id.buttonCamera);
buttonCamera.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
onLaunchCamera();
}
});
Button buttonGallery = findViewById(R.id.buttonGallery);
buttonGallery.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
onPickPhoto();
}
});
cameraActivityResultLauncher = registerForActivityResult(
new ActivityResultContracts.StartActivityForResult(),
result -> {
if (result.getResultCode() == Activity.RESULT_OK) {
Bitmap takenImage = loadFromUri(intermediateProvider);
ImageView ivPreview = findViewById(R.id.originView);
ivPreview.setImageBitmap(getResizedBitmap(takenImage, 400));
onCropImage();
}
});
galleryActivityResultLauncher = registerForActivityResult(
new ActivityResultContracts.StartActivityForResult(),
result -> {
if (result.getResultCode() == Activity.RESULT_OK && result.getData() != null) {
saveBitmapFileToIntermediate(result.getData().getData());
Bitmap selectedImage = loadFromUri(intermediateProvider);
ImageView ivPreview = findViewById(R.id.originView);
ivPreview.setImageBitmap(getResizedBitmap(selectedImage, 400));
onCropImage();
}
});
cropActivityResultLauncher = registerForActivityResult(
new ActivityResultContracts.StartActivityForResult(),
result -> {
if (result.getResultCode() == Activity.RESULT_OK) {
Bitmap cropImage = loadFromUri(resultProvider);
ImageView ivPreview = findViewById(R.id.resultView);
ivPreview.setImageBitmap(getResizedBitmap(cropImage, 400));
}
});
}
public void onLaunchCamera() {
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
File photoFile = getPhotoFileUri(intermediateName);
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.N)
intermediateProvider = FileProvider.getUriForFile(MainActivity.this, "com.photostream.crop.fileprovider", photoFile);
else
intermediateProvider = Uri.fromFile(photoFile);
intent.putExtra(MediaStore.EXTRA_OUTPUT, intermediateProvider);
if (intent.resolveActivity(getPackageManager()) != null) {
cameraActivityResultLauncher.launch(intent);
}
}
// Trigger gallery selection for a photo
public void onPickPhoto() {
Intent intent = new Intent(Intent.ACTION_PICK, MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
if (intent.resolveActivity(getPackageManager()) != null) {
galleryActivityResultLauncher.launch(intent);
}
}
private void onCropImage() {
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
grantUriPermission("com.android.camera", intermediateProvider, Intent.FLAG_GRANT_WRITE_URI_PERMISSION | Intent.FLAG_GRANT_READ_URI_PERMISSION);
Intent intent = new Intent("com.android.camera.action.CROP");
intent.setDataAndType(intermediateProvider, "image/*");
List<ResolveInfo> list = getPackageManager().queryIntentActivities(intent, 0);
int size = 0;
if(list != null) {
grantUriPermission(list.get(0).activityInfo.packageName, intermediateProvider, Intent.FLAG_GRANT_WRITE_URI_PERMISSION | Intent.FLAG_GRANT_READ_URI_PERMISSION);
size = list.size();
}
if (size == 0) {
Toast.makeText(this, "Error, wasn't taken image!", Toast.LENGTH_SHORT).show();
} else {
intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
intent.addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
intent.putExtra("crop", "true");
intent.putExtra("scale", true);
File photoFile = getPhotoFileUri(resultName);
// wrap File object into a content provider
// required for API >= 24
// See https://guides.codepath.com/android/Sharing-Content-with-Intents#sharing-files-with-api-24-or-higher
resultProvider = FileProvider.getUriForFile(MainActivity.this, "com.photostream.crop.fileprovider", photoFile);
intent.putExtra("return-data", false);
intent.putExtra(MediaStore.EXTRA_OUTPUT, resultProvider);
intent.putExtra("outputFormat", Bitmap.CompressFormat.JPEG.toString());
Intent cropIntent = new Intent(intent);
ResolveInfo res = list.get(0);
cropIntent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
cropIntent.addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
grantUriPermission(res.activityInfo.packageName, resultProvider, Intent.FLAG_GRANT_WRITE_URI_PERMISSION | Intent.FLAG_GRANT_READ_URI_PERMISSION);
cropIntent.setComponent(new ComponentName(res.activityInfo.packageName, res.activityInfo.name));
cropActivityResultLauncher.launch(cropIntent);
}
} else {
File photoFile = getPhotoFileUri(resultName);
resultProvider = Uri.fromFile(photoFile);
Intent intentCrop = new Intent("com.android.camera.action.CROP");
intentCrop.setFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
intentCrop.setFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
intentCrop.setDataAndType(intermediateProvider, "image/*");
intentCrop.putExtra("crop", "true");
intentCrop.putExtra("scale", true);
intentCrop.putExtra("outputFormat", Bitmap.CompressFormat.JPEG.toString());
intentCrop.putExtra("noFaceDetection", true);
intentCrop.putExtra("return-data", false);
intentCrop.putExtra(MediaStore.EXTRA_OUTPUT, resultProvider);
cropActivityResultLauncher.launch(intentCrop);
}
}
// Returns the File for a photo stored on disk given the fileName
public File getPhotoFileUri(String fileName) {
File mediaStorageDir = new File(getExternalFilesDir(""), APP_TAG);
if (!mediaStorageDir.exists() && !mediaStorageDir.mkdirs()){
Log.d(APP_TAG, "failed to create directory");
}
File file = new File(mediaStorageDir.getPath() + File.separator + fileName);
return file;
}
public Bitmap loadFromUri(Uri photoUri) {
Bitmap image = null;
try {
if(Build.VERSION.SDK_INT > Build.VERSION_CODES.O_MR1){
// on newer versions of Android, use the new decodeBitmap method
ImageDecoder.Source source = ImageDecoder.createSource(this.getContentResolver(), photoUri);
image = ImageDecoder.decodeBitmap(source);
} else {
// support older versions of Android by using getBitmap
image = MediaStore.Images.Media.getBitmap(this.getContentResolver(), photoUri);
}
} catch (IOException e) {
e.printStackTrace();
}
return image;
}
private void saveBitmapFileToIntermediate(Uri sourceUri) {
try {
Bitmap bitmap = loadFromUri(sourceUri);
File imageFile = getPhotoFileUri(intermediateName);
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.N)
intermediateProvider = FileProvider.getUriForFile(MainActivity.this, "com.photostream.crop.fileprovider", imageFile);
else
intermediateProvider = Uri.fromFile(imageFile);
OutputStream out = new FileOutputStream(imageFile);
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, out);
out.close();
} catch (Exception e) {
e.printStackTrace();
}
}
public Bitmap getResizedBitmap(Bitmap image, int maxSize) {
int width = image.getWidth();
int height = image.getHeight();
float bitmapRatio = (float)width / (float) height;
if (bitmapRatio > 1) {
width = maxSize;
height = (int) (width / bitmapRatio);
} else {
height = maxSize;
width = (int) (height * bitmapRatio);
}
return Bitmap.createScaledBitmap(image, width, height, true);
}
}
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
package="com.photostream.crop">
<queries>
<intent>
<action android:name="android.media.action.IMAGE_CAPTURE" />
</intent>
<intent>
<action android:name="com.android.camera.action.CROP" />
</intent>
<intent>
<action android:name="android.intent.action.PICK" />
<data android:mimeType="vnd.android.cursor.dir/image" />
</intent>
</queries>
<application
android:allowBackup="true"
android:largeHeap="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/Theme.Test">
<activity
android:name=".MainActivity"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<provider
android:name="androidx.core.content.FileProvider"
android:authorities="com.photostream.crop.fileprovider"
android:exported="false"
android:grantUriPermissions="true">
<meta-data
android:name="android.support.FILE_PROVIDER_PATHS"
android:resource="@xml/fileprovider" />
</provider>
</application>
</manifest>
它在 Android 11 上运行良好。您也可以参考 Github 上的关注项目。 https://github.com/bigant02/image-crop
我假设您以 Android 11 (API 30) 为目标，这要求您在 AndroidManifest.xml 内的节点中指定外部应用程序的所有意图，queries如下所示：
<queries>
...
<intent>
<action android:name="com.android.camera.action.CROP" />
</intent>
...
</queries>
注意：意图com.android.camera.action.CROP基于 AOSP 的相机应用程序，可能在某些设备上丢失，请参阅 Commonsware 的旧博客文章：https ://commonsware.com/blog/2013/01/23/no-android-does -not-have-crop-intent.html