在Stack Overflow的所有相关问题中进行了大量搜索,但一无所获之后,请尝试帮助我。
我创建了一个捕捉图片的意图。然后,我在onActivityResult()
中看到了不同的行为:如果我没有在Intent中添加任何额外内容(对于小图片),onActivityResult中的Intent是可以的,但是当我在Intent中将额外内容添加到将图片写入文件中时,onActivityCResult中的意图是null
!
意图创建:
Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
// without the following line the intent is ok
takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(f));
startActivityForResult(takePictureIntent, actionCode);
为什么是null,怎么解决?
如果您提供< code>MediaStore,我也会遇到同样的情况。EXTRA_OUTPUT,那么intent为null,但是您将在您提供的文件中拥有照片(< code>Uri.fromFile(f))。
如果不指定< code>MediaStore。EXTRA_OUTPUT然后您将有一个包含相机保存照片的文件的uri的意图。
不知道这是不是一个错误,但它就是这样工作的。
EDIT:所以在onActivityResult()中,如果为空,则不再需要检查数据。以下是我的工作经历:
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
switch (requestCode) {
case PICK_IMAGE_REQUEST://actionCode
if (resultCode == RESULT_OK && data != null && data.getData() != null) {
//For Image Gallery
}
return;
case CAPTURE_IMAGE_REQUEST://actionCode
if (resultCode == RESULT_OK) {
//For CAMERA
//You can use image PATH that you already created its file by the intent that launched the CAMERA (MediaStore.EXTRA_OUTPUT)
return;
}
}
}
希望有帮助
用Kotlin编写的示例。您为相机应用程序创建了一个Uri
,CameraFragment
保存它,直到相机保存图片后返回,并按照您的预期在onActivityResult
中将其返回给您。
充当消费者和相机应用程序之间的中介。将< code>Uri作为输入,并在data Intent
中返回它。
class CameraFragment : Fragment() {
companion object {
val TAG = CameraFragment::class.java.simpleName
private val KEY_URI = ".URI"
fun newInstance(uri: Uri, targetFragment: Fragment, requestCode: Int): CameraFragment {
val args = Bundle()
args.putParcelable(KEY_URI, uri)
val fragment = CameraFragment()
fragment.arguments = args
fragment.setTargetFragment(targetFragment, requestCode)
return fragment
}
}
private lateinit var uri: Uri
private var fired = false
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
retainInstance = true
fired = savedInstanceState?.getBoolean("fired") ?: false
if (!fired) {
val args = arguments
uri = args.getParcelable(KEY_URI)
val i = Intent(MediaStore.ACTION_IMAGE_CAPTURE)
i.putExtra(MediaStore.EXTRA_OUTPUT, uri)
i.addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION)
context.grantUriPermission(i, uri, Intent.FLAG_GRANT_WRITE_URI_PERMISSION)
startActivityForResult(i, targetRequestCode)
fired = true
}
}
override fun onSaveInstanceState(outState: Bundle) {
super.onSaveInstanceState(outState)
outState.putBoolean("fired", fired)
}
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
super.onActivityResult(requestCode, resultCode, data)
if (requestCode == targetRequestCode) {
context.revokeUriPermission(uri, Intent.FLAG_GRANT_WRITE_URI_PERMISSION)
val newData = Intent()
newData.data = uri
targetFragment.onActivityResult(requestCode, resultCode, newData)
dismiss()
}
}
private fun dismiss() {
fragmentManager.beginTransaction().remove(this).commit()
}
}
/** Grant Uri permissions for all camera apps. */
fun Context.grantUriPermission(intent: Intent, uri: Uri, modeFlags: Int) {
val resolvedIntentActivities = packageManager.queryIntentActivities(intent, PackageManager.MATCH_DEFAULT_ONLY);
for (resolvedIntentInfo in resolvedIntentActivities) {
val packageName = resolvedIntentInfo.activityInfo.packageName;
grantUriPermission(packageName, uri, modeFlags);
}
}
这
是应用程序中的一个片段,它将触发相机RC_CAMERA
是此操作的请求代码。
val uri = /* Your output Uri. */
val f = CameraFragment.newInstance(uri, this, RC_CAMERA)
fragmentManager.beginTransaction().add(f, CameraFragment.TAG).commit()
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
super.onActivityResult(requestCode, resultCode, data)
when(requestCode) {
RC_CAMERA -> {
if (resultCode == Activity.RESULT_OK) {
val uri = data?.data
// Do whatever you need.
}
}
}
}
您在哪里为< code>Uri.fromFile(f)创建了< code>f?
它必须是有效的< code>File对象。请尝试在< code>EXTRA_OUTPUT行之前创建它。
File f = new File("valid path");
试试这样的方法:
File file = new File(dataFile);
Uri outFileUri = Uri.fromFile(file);
Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
intent.putExtra(MediaStore.EXTRA_OUTPUT, outFileUri);
startActivityForResult(intent, TAKE_PHOTO);