我想写一个模块，在点击一个按钮，相机打开，我可以点击和捕捉图像。如果我不喜欢图像，我可以删除它，然后点击另一个图像，然后选择图像，它应该返回并在活动中显示该图像。
当前回答
2021年5月，爪哇
在处理了本文旁边所述的必要权限后， 在manifest中添加:
<uses-permission
android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission
android:name="android.permission.WRITE_EXTERNAL_STORAGE"
android:maxSdkVersion="18" />
<uses-permission android:name="android.permission.CAMERA" />
<uses-feature
android:name="android.hardware.camera"
android:required="true" />
....
<provider
android:name="androidx.core.content.FileProvider"
android:authorities="${applicationId}.fileprovider"
android:exported="false"
android:grantUriPermissions="true">
<meta-data
android:name="android.support.FILE_PROVIDER_PATHS"
android:resource="@xml/provider_paths" />
</provider>
....
其中${applicationId}是应用程序的包名，例如my.app.com。
在res - > xml > provider_paths.xml
<?xml version="1.0" encoding="utf-8"?>
<paths>
<external-files-path name="my_images" path="Pictures" />
<external-path name="external_files" path="."/>
<files-path
name="files" path="." />
<external-cache-path
name="images" path="." />
</paths>
在活动:
private void onClickCaptureButton(View view) {
Intent takePictureIntent_ = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
// 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 photoFile_ = null;
try {
photoFile_ = createImageFile();
} catch (IOException ex) {
}
if(photoFile_!=null){
picturePath=photoFile_.getAbsolutePath();
}
// Continue only if the File was successfully created
if (photoFile_ != null) {
Uri photoURI_ = FileProvider.getUriForFile(this,
"my.app.com.fileprovider", photoFile_);
takePictureIntent_.putExtra(MediaStore.EXTRA_OUTPUT, photoURI_);
startActivityForResult(takePictureIntent_, REQUEST_IMAGE_CAPTURE);
}
}
}
还有三招:
...
private static String picturePath;
private static final int REQUEST_IMAGE_CAPTURE = 2;
...
private File createImageFile() throws IOException {
// Create an image file name
String timeStamp_ = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new
Date());
String imageFileName_ = "JPEG_" + timeStamp_ + "_";
File storageDir_ = getExternalFilesDir(Environment.DIRECTORY_PICTURES);
File image_ = File.createTempFile(
imageFileName_, /* prefix */
".jpg", /* suffix */
storageDir_ /* directory */
);
// Save a file: path for use with ACTION_VIEW intents
picturePath= image_.getAbsolutePath();
return image_;
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if(requestCode == REQUEST_IMAGE_CAPTURE && resultCode == Activity.RESULT_OK
){
try {
File file_ = new File(picturePath);
Uri uri_ = FileProvider.getUriForFile(this,
"my.app.com.fileprovider", file_);
rasm.setImageURI(uri_);
} catch (/*IO*/Exception e) {
e.printStackTrace();
}
}
}
and
@Override
public void onSaveInstanceState(Bundle savedInstanceState) {
savedInstanceState.putString("safar", picturePath);
// Always call the superclass so it can save the view hierarchy state
super.onSaveInstanceState(savedInstanceState);
}
and:
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (savedInstanceState != null) {
picturePath = savedInstanceState.getString("safar");
}
....
}
其他回答
2021年5月，爪哇
在处理了本文旁边所述的必要权限后， 在manifest中添加:
<uses-permission
android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission
android:name="android.permission.WRITE_EXTERNAL_STORAGE"
android:maxSdkVersion="18" />
<uses-permission android:name="android.permission.CAMERA" />
<uses-feature
android:name="android.hardware.camera"
android:required="true" />
....
<provider
android:name="androidx.core.content.FileProvider"
android:authorities="${applicationId}.fileprovider"
android:exported="false"
android:grantUriPermissions="true">
<meta-data
android:name="android.support.FILE_PROVIDER_PATHS"
android:resource="@xml/provider_paths" />
</provider>
....
其中${applicationId}是应用程序的包名，例如my.app.com。
在res - > xml > provider_paths.xml
<?xml version="1.0" encoding="utf-8"?>
<paths>
<external-files-path name="my_images" path="Pictures" />
<external-path name="external_files" path="."/>
<files-path
name="files" path="." />
<external-cache-path
name="images" path="." />
</paths>
在活动:
private void onClickCaptureButton(View view) {
Intent takePictureIntent_ = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
// 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 photoFile_ = null;
try {
photoFile_ = createImageFile();
} catch (IOException ex) {
}
if(photoFile_!=null){
picturePath=photoFile_.getAbsolutePath();
}
// Continue only if the File was successfully created
if (photoFile_ != null) {
Uri photoURI_ = FileProvider.getUriForFile(this,
"my.app.com.fileprovider", photoFile_);
takePictureIntent_.putExtra(MediaStore.EXTRA_OUTPUT, photoURI_);
startActivityForResult(takePictureIntent_, REQUEST_IMAGE_CAPTURE);
}
}
}
还有三招:
...
private static String picturePath;
private static final int REQUEST_IMAGE_CAPTURE = 2;
...
private File createImageFile() throws IOException {
// Create an image file name
String timeStamp_ = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new
Date());
String imageFileName_ = "JPEG_" + timeStamp_ + "_";
File storageDir_ = getExternalFilesDir(Environment.DIRECTORY_PICTURES);
File image_ = File.createTempFile(
imageFileName_, /* prefix */
".jpg", /* suffix */
storageDir_ /* directory */
);
// Save a file: path for use with ACTION_VIEW intents
picturePath= image_.getAbsolutePath();
return image_;
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if(requestCode == REQUEST_IMAGE_CAPTURE && resultCode == Activity.RESULT_OK
){
try {
File file_ = new File(picturePath);
Uri uri_ = FileProvider.getUriForFile(this,
"my.app.com.fileprovider", file_);
rasm.setImageURI(uri_);
} catch (/*IO*/Exception e) {
e.printStackTrace();
}
}
}
and
@Override
public void onSaveInstanceState(Bundle savedInstanceState) {
savedInstanceState.putString("safar", picturePath);
// Always call the superclass so it can save the view hierarchy state
super.onSaveInstanceState(savedInstanceState);
}
and:
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (savedInstanceState != null) {
picturePath = savedInstanceState.getString("safar");
}
....
}
请使用Kotlin和Andoirdx支持来实现这个例子:
button1.setOnClickListener{
file = getPhotoFile()
val uri: Uri = FileProvider.getUriForFile(applicationContext, "com.example.foto_2.filrprovider", file!!)
captureImage.putExtra(MediaStore.EXTRA_OUTPUT, uri)
val camaraActivities: List<ResolveInfo> = applicationContext.getPackageManager().queryIntentActivities(captureImage, PackageManager.MATCH_DEFAULT_ONLY)
for (activity in camaraActivities) {
applicationContext.grantUriPermission(activity.activityInfo.packageName, uri, Intent.FLAG_GRANT_WRITE_URI_PERMISSION)
}
startActivityForResult(captureImage, REQUEST_PHOTO)
}
活动结果:
if (requestCode == REQUEST_PHOTO) {
val uri = FileProvider.getUriForFile(applicationContext, "com.example.foto_2.filrprovider", file!!)
applicationContext.revokeUriPermission(uri, Intent.FLAG_GRANT_WRITE_URI_PERMISSION)
imageView1.viewTreeObserver.addOnGlobalLayoutListener {
width = imageView1.width
height = imageView1.height
imageView1.setImageBitmap(getScaleBitmap(file!!.path , width , height))
}
if(width!=0&&height!=0){
imageView1.setImageBitmap(getScaleBitmap(file!!.path , width , height))
}else{
val size = Point()
this.windowManager.defaultDisplay.getSize(size)
imageView1.setImageBitmap(getScaleBitmap(file!!.path , size.x , size.y))
}
}
您可以在https://github.com/joelmmx/take_photo_kotlin.git上获得更多详细信息
我希望它能帮助你!
你得好好研究一下相机。(我认为要做到你想要的，你必须保存当前的图像到你的应用程序，在那里做选择/删除，然后召回相机再试一次，而不是直接在相机内部重试。)
正如其他人所讨论的，使用data. getextras ().get("data")只会得到低质量的缩略图。
解决方案是通过ACTION_IMAGE_CAPTURE意图传递一个位置，告诉相机在哪里存储全质量图像。
代码是Kotlin，不需要任何权限。
val f = File("${getExternalFilesDir(null)}/imgShot")
val photoURI = FileProvider.getUriForFile(this, "${packageName}.fileprovider", f)
val intent = Intent(MediaStore.ACTION_IMAGE_CAPTURE)
.apply { putExtra(MediaStore.EXTRA_OUTPUT, photoURI) }
startActivityForResult(intent, 1234)
然后对拍摄后的结果进行处理:
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
if (requestCode == 1234 && resultCode == Activity.RESULT_OK) {
val bitmap = BitmapFactory.decodeFile(
File("${getExternalFilesDir(null)}/imgShot").toString()
)
// use imageView.setImageBitmap(bitmap) or whatever
}
}
您还需要像这里描述的那样添加一个外部FileProvider。AndroidManifest.xml:
<manifest>
<application>
<provider
android:name="androidx.core.content.FileProvider"
android:authorities="${applicationId}.fileprovider"
android:exported="false"
android:grantUriPermissions="true">
<meta-data
android:name="android.support.FILE_PROVIDER_PATHS"
android:resource="@xml/provide_paths" />
</provider>
</application>
</manifest>
添加一个新文件app/src/main/res/xml/provide_paths.xml:
<?xml version="1.0" encoding="utf-8"?>
<paths>
<external-path name="external_files" path="." />
</paths>
最后，你应该用你自己的逻辑替换1234来跟踪请求代码(通常是一个包含RequestCode.CAPTURE_IMAGE等成员的枚举)
位图照片=(位图)data. getextras ().get("data");从相机获取缩略图。有一篇文章是关于如何将照片从相机存储到外部存储器中。 有用的链接
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