I'm developing a punch clock in a tablet with Flutter Application and I need this functionality.
I know how to make the camera show and the user make a screenshot, but I searched everywhere how to make an automatic self screenshot after 3 seconds and don't find anything.
Someone has an example, tutorial, or experience to make something like this?
You can use Timer class to do some action after certain time duration as shown below
Timer(Duration(milliseconds: 3000), () {
//after 3 seconds this will be called,
//once this is called take picture or whatever function you need to do
takeScreenshot();
});
And if you want,use this code below to take screenshot as mentioned in this answer Take Screenshot Stackoverflow answer
takeScreenShot() async{
RenderRepaintBoundary boundary =
previewContainer.currentContext.findRenderObject();
ui.Image image = await boundary.toImage();
final directory = (await getApplicationDocumentsDirectory()).path;
ByteData byteData = await image.toByteData(format: ui.ImageByteFormat.png);
Uint8List pngBytes = byteData.buffer.asUint8List();
print(pngBytes);
File imgFile =new File('$directory/screenshot.png');
imgFile.writeAsBytes(pngBytes);
}
Hope this helps!
Related
I have a floating action button that I want a user to click to take a picture with their camera and then have that image replace the camera icon on the floating action bar button.
Here is the code for my FAB, and including uploading the image to firestore storage.
floatingActionButton: FloatingActionButton.large(
heroTag: "add image",
backgroundColor: const Color(0xFF93C3B9),
child: (imageURL == ' ')
? const Icon(Icons.add_a_photo_outlined)
: Image.network(imageURL),
//open add gear page
onPressed: () async {
// todo: upload an image to Firebase Storage
//Take picture
ImagePicker imagePicker = ImagePicker();
XFile? file = await imagePicker.pickImage(source: ImageSource.camera);
if (file == null) return;
String uniqueFileName =
DateTime.now().millisecondsSinceEpoch.toString();
//Get reference to storage root
Reference referenceRoot = FirebaseStorage.instance.ref();
Reference referenceDirImages = referenceRoot.child('images/$userID');
Reference referenceImageToUpload =
referenceDirImages.child(uniqueFileName);
try {
//upload image
await referenceImageToUpload.putFile(File(file.path));
//get download URL
setState(() async {
imageURL = await referenceImageToUpload.getDownloadURL();
print(imageURL);
});
//upload path to fireStore database
} catch (error) {}
},
),
After the image uploads it's like the set state is not working to replace the icon with the image. The odd part is is I crtl-s and save in Visual Studio Code then the widgets seem to rebuild and then the image is visible there...
So after playing around with my code a bit I decided to edit the above code and take tha await function out of the setState() and make setState() not async anymore:
//get download URL
String tempUrl = await referenceImageToUpload.getDownloadURL();
setState(() {
print("--------- Set State -----------");
imageURL = tempUrl;
print("--------- Set State end -----------");
});
print("New image url $imageURL ------------");
not sure why it works, but this solves my issue.
By your description of the issue, I think you might be using StatelessWidget instead of StatefulWidget.
You see the button change when performing a hotreload because the value of imageURL is correctly changing internally, but you need a StatefulWidget to update the UI also.
Hope it helps!
In Flutter, how do you get a screenshot for an arbitrary screen resolution? I.e. for a screen resolution that's different from the resolution the app is running in?
Is there a way to tell the Flutter engine to paint a single frame into a buffer with a specific resolution?
What I'm trying to accomplish is to generate the screenshots for the various app stores from within the app, but without scaling and cropping screenshots that were taken for different devices/resolutions.
How would you tackle that requirement?
Any advise is welcome,
Thank you!
if you are talking about taking a screenshot of a particular widget and saving it
the you have to use renderrepaint boundry with key .
dependencies - path provider
Image gallery saver ..
takeScreenshot(BuildContext context,GlobalKey _key,String slug) async {
RenderRepaintBoundary boundary = _key.currentContext.findRenderObject();
ui.Image image = await boundary.toImage(pixelRatio: 3.0);
final snackBar = SnackBar(content: Text("Image saved to gallery"));
ScaffoldMessenger.of(context).showSnackBar(snackBar);
final directory = (await getApplicationDocumentsDirectory()).path;
ByteData byteData = await image.toByteData(format: ui.ImageByteFormat.png);
final result = await ImageGallerySaver.saveImage(
byteData.buffer.asUint8List(),
name: "name.jpg");
}
Here is the code I use to do a screenshot.
First, I placed the widget inside RepaintBoundary.
RepaintBoundary(
key: widgetKey,
child: childWidget,
),
Then somewhere else in the code, we initiate a screenshot with the following code.
/// Note: Delay added to the actual code ensuring widget finish rendering.
final RenderRepaintBoundary boundary =
widgetKey.currentContext!.findRenderObject() as RenderRepaintBoundary;
final image = await boundary.toImage(pixelRatio: pixelRatio);
final byteData = await image.toByteData(format: ui.ImageByteFormat.png);
The above code works for any widget except PlatformView widgets, which return an empty picture.
I've read the issues on Github #25306 and #83856.
They are closed, but the problem persists.
I've added a 2 seconds delay, but it still doesn't work.
Can someone help? Thanks
I have an image with a container on it. I want to be able to edit the TextField inside the container and save the image as an image to the device.
My current setup is a stack where I have the image and a container on top of each other. How can I save that as an image?
Note that I don't want to save the whole screen, just the image and whatever on it.
Future<File> createWave(BuildContext context, GlobalKey screen) async {
RenderRepaintBoundary boundary = screen.currentContext.findRenderObject();
ui.Image image = await boundary.toImage();
ByteData byteData = await image.toByteData(format: ui.ImageByteFormat.png);
Uint8List pngBytes = byteData.buffer.asUint8List();
final directory = (await getApplicationDocumentsDirectory()).path;
File imgFile = File('$directory/screenshot.png');
await imgFile.writeAsBytes(pngBytes);
return imgFile;
}
Thankfully since flutter uses skia to render it's graphics, we are able to take screenshots of widgets and there is already a really good article that does somethings similar. Basically you wrap your widget in a RepaintBoundary and assign it a key then use the key to call the RenderObject.toImage method. Here is another simple example to do this. It's amazing how simple it is :D
I'm using a native surface view in a flutter When I take a screenshot using a repaint boundary widget. black screen issue occurs.
My code :
RenderRepaintBoundary boundary =_globalKey.currentContext.findRenderObject();
ui.Image image = await boundary.toImage(pixelRatio: 3.0);
ByteData byteData =
await image.toByteData(format: ui.ImageByteFormat.png);
Please guide me for solution