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- Architectural overview of Cordova platform
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- Config.xml
- 事件
- CLI Reference
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- Plugin.xml reference documentation
- Battery Status
- Camera
- Console
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- Device Motion
- Device Orientation
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- File
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- Geolocation
- Globalization
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- Media
- Media Capture
- Network Information
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- Vibration
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- Whitelist
- Legacy Whitelist
Camera
This plugin defines a global navigator.camera
object, which provides an API for taking pictures and for choosing images from the system's image library.
Although the object is attached to the global scoped navigator
, it is not available until after the deviceready
event.
document.addEventListener("deviceready", onDeviceReady, false);
function onDeviceReady() {
console.log(navigator.camera);
}
Installation
This requires cordova 5.0+
cordova plugin add cordova-plugin-camera
Older versions of cordova can still install via the deprecated id
cordova plugin add org.apache.cordova.camera
It is also possible to install via repo url directly ( unstable )
cordova plugin add https://github.com/apache/cordova-plugin-camera.git
How to Contribute
Contributors are welcome! And we need your contributions to keep the project moving forward. You can report bugs, improve the documentation, or contribute code.
There is a specific contributor workflow we recommend. Start reading there. More information is available on our wiki.
:warning: Found an issue? File it on JIRA issue tracker.
Have a solution? Send a Pull Request.
In order for your changes to be accepted, you need to sign and submit an Apache ICLA (Individual Contributor License Agreement). Then your name will appear on the list of CLAs signed by non-committers or Cordova committers.
And don't forget to test and document your code.
This documentation is generated by a tool
:warning: Run npm install
in the plugin repo to enable automatic docs generation if you plan to send a PR.
jsdoc-to-markdown is used to generate the docs.
Documentation consists of template and API docs produced from the plugin JS code and should be regenerated before each commit (done automatically via husky, running npm run gen-docs
script as a precommit
hook - see package.json
for details).
camera
- .getPicture(successCallback, errorCallback, options)
- .cleanup()
- .onError :
function
- .onSuccess :
function
- .CameraOptions :
Object
Camera
- .DestinationType :
enum
- .EncodingType :
enum
- .MediaType :
enum
- .PictureSourceType :
enum
- .PopoverArrowDirection :
enum
- .Direction :
enum
- .DestinationType :
CameraPopoverHandle
CameraPopoverOptions
camera
camera.getPicture(successCallback, errorCallback, options)
Takes a photo using the camera, or retrieves a photo from the device's image gallery. The image is passed to the success callback as a Base64-encoded String
, or as the URI for the image file.
The camera.getPicture
function opens the device's default camera application that allows users to snap pictures by default - this behavior occurs, when Camera.sourceType
equals Camera.PictureSourceType.CAMERA
. Once the user snaps the photo, the camera application closes and the application is restored.
If Camera.sourceType
is Camera.PictureSourceType.PHOTOLIBRARY
or Camera.PictureSourceType.SAVEDPHOTOALBUM
, then a dialog displays that allows users to select an existing image. The camera.getPicture
function returns a CameraPopoverHandle
object, which can be used to reposition the image selection dialog, for example, when the device orientation changes.
The return value is sent to the cameraSuccess
callback function, in one of the following formats, depending on the specified cameraOptions
:
A
String
containing the Base64-encoded photo image.A
String
representing the image file location on local storage (default).
You can do whatever you want with the encoded image or URI, for example:
Render the image in an
<img>
tag, as in the example belowSave the data locally (
LocalStorage
, Lawnchair, etc.)Post the data to a remote server
NOTE: Photo resolution on newer devices is quite good. Photos selected from the device's gallery are not downscaled to a lower quality, even if a quality
parameter is specified. To avoid common memory problems, set Camera.destinationType
to FILE_URI
rather than DATA_URL
.
Supported Platforms
- Android
- BlackBerry
- Browser
- Firefox
- FireOS
- iOS
- Windows
- WP8
- Ubuntu
More examples here. Quirks here.
Kind: static method of camera
Param | Type | Description |
---|---|---|
successCallback | onSuccess | |
errorCallback | onError | |
options | CameraOptions | CameraOptions |
Example
navigator.camera.getPicture(cameraSuccess, cameraError, cameraOptions);
camera.cleanup()
Removes intermediate image files that are kept in temporary storage after calling camera.getPicture
. Applies only when the value of Camera.sourceType
equals Camera.PictureSourceType.CAMERA
and the Camera.destinationType
equals Camera.DestinationType.FILE_URI
.
Supported Platforms
- iOS
Kind: static method of camera
Example
navigator.camera.cleanup(onSuccess, onFail);
function onSuccess() {
console.log("Camera cleanup success.")
}
function onFail(message) {
alert('Failed because: ' + message);
}
camera.onError : function
Callback function that provides an error message.
Kind: static typedef of camera
Param | Type | Description |
---|---|---|
message | string | The message is provided by the device's native code. |
camera.onSuccess : function
Callback function that provides the image data.
Kind: static typedef of camera
Param | Type | Description |
---|---|---|
imageData | string | Base64 encoding of the image data, or the image file URI, depending on cameraOptions in effect. |
Example
// Show image
//
function cameraCallback(imageData) {
var image = document.getElementById('myImage');
image.src = "data:image/jpeg;base64," + imageData;
}
camera.CameraOptions : Object
Optional parameters to customize the camera settings.
- Quirks
Kind: static typedef of camera
Properties
Name | Type | Default | Description |
---|---|---|---|
quality | number | 50 | Quality of the saved image, expressed as a range of 0-100, where 100 is typically full resolution with no loss from file compression. (Note that information about the camera's resolution is unavailable.) |
destinationType | DestinationType | FILE_URI | Choose the format of the return value. |
sourceType | PictureSourceType | CAMERA | Set the source of the picture. |
allowEdit | Boolean | true | Allow simple editing of image before selection. |
encodingType | EncodingType | JPEG | Choose the returned image file's encoding. |
targetWidth | number | Width in pixels to scale image. Must be used with targetHeight . Aspect ratio remains constant. | |
targetHeight | number | Height in pixels to scale image. Must be used with targetWidth . Aspect ratio remains constant. | |
mediaType | MediaType | PICTURE | Set the type of media to select from. Only works when PictureSourceType is PHOTOLIBRARY or SAVEDPHOTOALBUM . |
correctOrientation | Boolean | Rotate the image to correct for the orientation of the device during capture. | |
saveToPhotoAlbum | Boolean | Save the image to the photo album on the device after capture. | |
popoverOptions | CameraPopoverOptions | iOS-only options that specify popover location in iPad. | |
cameraDirection | Direction | BACK | Choose the camera to use (front- or back-facing). |
Camera
Camera.DestinationType : enum
Kind: static enum property of Camera
Properties
Name | Type | Default | Description |
---|---|---|---|
DATA_URL | number | 0 | Return base64 encoded string. DATAURL can be very memory intensive and cause app crashes or out of memory errors. Use FILEURI or NATIVE_URI if possible |
FILE_URI | number | 1 | Return file uri (content://media/external/images/media/2 for Android) |
NATIVE_URI | number | 2 | Return native uri (eg. asset-library://... for iOS) |
Camera.EncodingType : enum
Kind: static enum property of Camera
Properties
Name | Type | Default | Description |
---|---|---|---|
JPEG | number | 0 | Return JPEG encoded image |
PNG | number | 1 | Return PNG encoded image |
Camera.MediaType : enum
Kind: static enum property of Camera
Properties
Name | Type | Default | Description |
---|---|---|---|
PICTURE | number | 0 | Allow selection of still pictures only. DEFAULT. Will return format specified via DestinationType |
VIDEO | number | 1 | Allow selection of video only, ONLY RETURNS URL |
ALLMEDIA | number | 2 | Allow selection from all media types |
Camera.PictureSourceType : enum
Kind: static enum property of Camera
Properties
Name | Type | Default | Description |
---|---|---|---|
PHOTOLIBRARY | number | 0 | Choose image from picture library (same as SAVEDPHOTOALBUM for Android) |
CAMERA | number | 1 | Take picture from camera |
SAVEDPHOTOALBUM | number | 2 | Choose image from picture library (same as PHOTOLIBRARY for Android) |
Camera.PopoverArrowDirection : enum
Matches iOS UIPopoverArrowDirection constants to specify arrow location on popover.
Kind: static enum property of Camera
Properties
Name | Type | Default |
---|---|---|
ARROW_UP | number | 1 |
ARROW_DOWN | number | 2 |
ARROW_LEFT | number | 4 |
ARROW_RIGHT | number | 8 |
ARROW_ANY | number | 15 |
Camera.Direction : enum
Kind: static enum property of Camera
Properties
Name | Type | Default | Description |
---|---|---|---|
BACK | number | 0 | Use the back-facing camera |
FRONT | number | 1 | Use the front-facing camera |
CameraPopoverOptions
iOS-only parameters that specify the anchor element location and arrow direction of the popover when selecting images from an iPad's library or album. Note that the size of the popover may change to adjust to the direction of the arrow and orientation of the screen. Make sure to account for orientation changes when specifying the anchor element location.
Param | Type | Default | Description |
---|---|---|---|
[x] | Number | 0 | x pixel coordinate of screen element onto which to anchor the popover. |
[y] | Number | 32 | y pixel coordinate of screen element onto which to anchor the popover. |
[width] | Number | 320 | width, in pixels, of the screen element onto which to anchor the popover. |
[height] | Number | 480 | height, in pixels, of the screen element onto which to anchor the popover. |
[arrowDir] | PopoverArrowDirection | ARROW_ANY | Direction the arrow on the popover should point. |
CameraPopoverHandle
A handle to an image picker popover.
Supported Platforms
- iOS
Example
var cameraPopoverHandle = navigator.camera.getPicture(onSuccess, onFail,
{
destinationType: Camera.DestinationType.FILE_URI,
sourceType: Camera.PictureSourceType.PHOTOLIBRARY,
popoverOptions: new CameraPopoverOptions(300, 300, 100, 100, Camera.PopoverArrowDirection.ARROW_ANY)
});
// Reposition the popover if the orientation changes.
window.onorientationchange = function() {
var cameraPopoverOptions = new CameraPopoverOptions(0, 0, 100, 100, Camera.PopoverArrowDirection.ARROW_ANY);
cameraPopoverHandle.setPosition(cameraPopoverOptions);
}
camera.getPicture
Errata
Example
Take a photo and retrieve the image's file location:
navigator.camera.getPicture(onSuccess, onFail, { quality: 50,
destinationType: Camera.DestinationType.FILE_URI });
function onSuccess(imageURI) {
var image = document.getElementById('myImage');
image.src = imageURI;
}
function onFail(message) {
alert('Failed because: ' + message);
}
Take a photo and retrieve it as a Base64-encoded image:
/**
* Warning: Using DATA_URL is not recommended! The DATA_URL destination
* type is very memory intensive, even with a low quality setting. Using it
* can result in out of memory errors and application crashes. Use FILE_URI
* or NATIVE_URI instead.
*/
navigator.camera.getPicture(onSuccess, onFail, { quality: 25,
destinationType: Camera.DestinationType.DATA_URL
});
function onSuccess(imageData) {
var image = document.getElementById('myImage');
image.src = "data:image/jpeg;base64," + imageData;
}
function onFail(message) {
alert('Failed because: ' + message);
}
Preferences (iOS)
CameraUsesGeolocation (boolean, defaults to false). For capturing JPEGs, set to true to get geolocation data in the EXIF header. This will trigger a request for geolocation permissions if set to true.
<preference name="CameraUsesGeolocation" value="false" />
Amazon Fire OS Quirks
Amazon Fire OS uses intents to launch the camera activity on the device to capture images, and on phones with low memory, the Cordova activity may be killed. In this scenario, the image may not appear when the Cordova activity is restored.
Android Quirks
Android uses intents to launch the camera activity on the device to capture images, and on phones with low memory, the Cordova activity may be killed. In this scenario, the result from the plugin call will be delivered via the resume event. See the Android Lifecycle guide for more information. The pendingResult.result
value will contain the value that would be passed to the callbacks (either the URI/URL or an error message). Check the pendingResult.pluginStatus
to determine whether or not the call was successful.
Browser Quirks
Can only return photos as Base64-encoded image.
Firefox OS Quirks
Camera plugin is currently implemented using Web Activities.
iOS Quirks
Including a JavaScript alert()
in either of the callback functions can cause problems. Wrap the alert within a setTimeout()
to allow the iOS image picker or popover to fully close before the alert displays:
setTimeout(function() {
// do your thing here!
}, 0);
Windows Phone 7 Quirks
Invoking the native camera application while the device is connected via Zune does not work, and triggers an error callback.
Tizen Quirks
Tizen only supports a destinationType
of Camera.DestinationType.FILE_URI
and a sourceType
of Camera.PictureSourceType.PHOTOLIBRARY
.
CameraOptions
Errata
Amazon Fire OS Quirks
Any
cameraDirection
value results in a back-facing photo.Ignores the
allowEdit
parameter.Camera.PictureSourceType.PHOTOLIBRARY
andCamera.PictureSourceType.SAVEDPHOTOALBUM
both display the same photo album.
Android Quirks
Any
cameraDirection
value results in a back-facing photo.allowEdit
is unpredictable on Android and it should not be used! The Android implementation of this plugin tries to find and use an application on the user's device to do image cropping. The plugin has no control over what application the user selects to perform the image cropping and it is very possible that the user could choose an incompatible option and cause the plugin to fail. This sometimes works because most devices come with an application that handles cropping in a way that is compatible with this plugin (Google Plus Photos), but it is unwise to rely on that being the case. If image editing is essential to your application, consider seeking a third party library or plugin that provides its own image editing utility for a more robust solution.Camera.PictureSourceType.PHOTOLIBRARY
andCamera.PictureSourceType.SAVEDPHOTOALBUM
both display the same photo album.Ignores the
encodingType
parameter if the image is unedited (i.e.quality
is 100,correctOrientation
is false, and notargetHeight
ortargetWidth
are specified). TheCAMERA
source will always return the JPEG file given by the native camera and thePHOTOLIBRARY
andSAVEDPHOTOALBUM
sources will return the selected file in its existing encoding.
BlackBerry 10 Quirks
Ignores the
quality
parameter.Ignores the
allowEdit
parameter.Camera.MediaType
is not supported.Ignores the
correctOrientation
parameter.Ignores the
cameraDirection
parameter.
Firefox OS Quirks
Ignores the
quality
parameter.Camera.DestinationType
is ignored and equals1
(image file URI)Ignores the
allowEdit
parameter.Ignores the
PictureSourceType
parameter (user chooses it in a dialog window)Ignores the
encodingType
Ignores the
targetWidth
andtargetHeight
Camera.MediaType
is not supported.Ignores the
correctOrientation
parameter.Ignores the
cameraDirection
parameter.
iOS Quirks
When using
destinationType.FILE_URI
, photos are saved in the application's temporary directory. The contents of the application's temporary directory is deleted when the application ends.When using
destinationType.NATIVE_URI
andsourceType.CAMERA
, photos are saved in the saved photo album regardless on the value ofsaveToPhotoAlbum
parameter.
Tizen Quirks
options not supported
always returns a FILE URI
Windows Phone 7 and 8 Quirks
Ignores the
allowEdit
parameter.Ignores the
correctOrientation
parameter.Ignores the
cameraDirection
parameter.Ignores the
saveToPhotoAlbum
parameter. IMPORTANT: All images taken with the WP8/8 Cordova camera API are always copied to the phone's camera roll. Depending on the user's settings, this could also mean the image is auto-uploaded to their OneDrive. This could potentially mean the image is available to a wider audience than your app intended. If this is a blocker for your application, you will need to implement the CameraCaptureTask as documented on MSDN. You may also comment or up-vote the related issue in the issue tracker.Ignores the
mediaType
property ofcameraOptions
as the Windows Phone SDK does not provide a way to choose videos from PHOTOLIBRARY.
Sample: Take Pictures, Select Pictures from the Picture Library, and Get Thumbnails
The Camera plugin allows you to do things like open the device's Camera app and take a picture, or open the file picker and select one. The code snippets in this section demonstrate different tasks including:
- Open the Camera app and take a Picture
- Take a picture and return thumbnails (resized picture)
- Take a picture and generate a FileEntry object
- Select a file from the picture library
- Select a JPEG image and return thumbnails (resized image)
- Select an image and generate a FileEntry object
Take a Picture
Before you can take a picture, you need to set some Camera plugin options to pass into the Camera plugin's getPicture
function. Here is a common set of recommendations. In this example, you create the object that you will use for the Camera options, and set the sourceType
dynamically to support both the Camera app and the file picker.
function setOptions(srcType) {
var options = {
// Some common settings are 20, 50, and 100
quality: 50,
destinationType: Camera.DestinationType.FILE_URI,
// In this app, dynamically set the picture source, Camera or photo gallery
sourceType: srcType,
encodingType: Camera.EncodingType.JPEG,
mediaType: Camera.MediaType.PICTURE,
allowEdit: true,
correctOrientation: true //Corrects Android orientation quirks
}
return options;
}
Typically, you want to use a FILEURI instead of a DATAURL to avoid most memory issues. JPEG is the recommended encoding type for Android.
You take a picture by passing in the options object to getPicture
, which takes a CameraOptions object as the third argument. When you call setOptions
, pass Camera.PictureSourceType.CAMERA
as the picture source.
function openCamera(selection) {
var srcType = Camera.PictureSourceType.CAMERA;
var options = setOptions(srcType);
var func = createNewFileEntry;
navigator.camera.getPicture(function cameraSuccess(imageUri) {
displayImage(imageUri);
// You may choose to copy the picture, save it somewhere, or upload.
func(imageUri);
}, function cameraError(error) {
console.debug("Unable to obtain picture: " + error, "app");
}, options);
}
Once you take the picture, you can display it or do something else. In this example, call the app's displayImage
function from the preceding code.
function displayImage(imgUri) {
var elem = document.getElementById('imageFile');
elem.src = imgUri;
}
To display the image on some platforms, you might need to include the main part of the URI in the Content-Security-Policy element in index.html. For example, on Windows 10, you can include ms-appdata:
in your element. Here is an example.
<meta http-equiv="Content-Security-Policy" content="default-src 'self' data: gap: ms-appdata: https://ssl.gstatic.com 'unsafe-eval'; style-src 'self' 'unsafe-inline'; media-src *">
Take a Picture and Return Thumbnails (Resize the Picture)
To get smaller images, you can return a resized image by passing both targetHeight
and targetWidth
values with your CameraOptions object. In this example, you resize the returned image to fit in a 100px by 100px box (the aspect ratio is maintained, so 100px is either the height or width, whichever is greater in the source).
function openCamera(selection) {
var srcType = Camera.PictureSourceType.CAMERA;
var options = setOptions(srcType);
var func = createNewFileEntry;
if (selection == "camera-thmb") {
options.targetHeight = 100;
options.targetWidth = 100;
}
navigator.camera.getPicture(function cameraSuccess(imageUri) {
// Do something
}, function cameraError(error) {
console.debug("Unable to obtain picture: " + error, "app");
}, options);
}
Select a File from the Picture Library
When selecting a file using the file picker, you also need to set the CameraOptions object. In this example, set the sourceType
to Camera.PictureSourceType.SAVEDPHOTOALBUM
. To open the file picker, call getPicture
just as you did in the previous example, passing in the success and error callbacks along with CameraOptions object.
function openFilePicker(selection) {
var srcType = Camera.PictureSourceType.SAVEDPHOTOALBUM;
var options = setOptions(srcType);
var func = createNewFileEntry;
navigator.camera.getPicture(function cameraSuccess(imageUri) {
// Do something
}, function cameraError(error) {
console.debug("Unable to obtain picture: " + error, "app");
}, options);
}
Select an Image and Return Thumbnails (resized images)
Resizing a file selected with the file picker works just like resizing using the Camera app; set the targetHeight
and targetWidth
options.
function openFilePicker(selection) {
var srcType = Camera.PictureSourceType.SAVEDPHOTOALBUM;
var options = setOptions(srcType);
var func = createNewFileEntry;
if (selection == "picker-thmb") {
// To downscale a selected image,
// Camera.EncodingType (e.g., JPEG) must match the selected image type.
options.targetHeight = 100;
options.targetWidth = 100;
}
navigator.camera.getPicture(function cameraSuccess(imageUri) {
// Do something with image
}, function cameraError(error) {
console.debug("Unable to obtain picture: " + error, "app");
}, options);
}
Take a picture and get a FileEntry Object
If you want to do something like copy the image to another location, or upload it somewhere using the FileTransfer plugin, you need to get a FileEntry object for the returned picture. To do that, call window.resolveLocalFileSystemURL
on the file URI returned by the Camera app. If you need to use a FileEntry object, set the destinationType
to Camera.DestinationType.FILE_URI
in your CameraOptions object (this is also the default value).
Note You need the File plugin to call
window.resolveLocalFileSystemURL
.
Here is the call to window.resolveLocalFileSystemURL
. The image URI is passed to this function from the success callback of getPicture
. The success handler of resolveLocalFileSystemURL
receives the FileEntry object.
function getFileEntry(imgUri) {
window.resolveLocalFileSystemURL(imgUri, function success(fileEntry) {
// Do something with the FileEntry object, like write to it, upload it, etc.
// writeFile(fileEntry, imgUri);
console.log("got file: " + fileEntry.fullPath);
// displayFileData(fileEntry.nativeURL, "Native URL");
}, function () {
// If don't get the FileEntry (which may happen when testing
// on some emulators), copy to a new FileEntry.
createNewFileEntry(imgUri);
});
}
In the example shown in the preceding code, you call the app's createNewFileEntry
function if you don't get a valid FileEntry object. The image URI returned from the Camera app should result in a valid FileEntry, but platform behavior on some emulators may be different for files returned from the file picker.
Note To see an example of writing to a FileEntry, see the File plugin README.
The code shown here creates a file in your app's cache (in sandboxed storage) named tempFile.jpeg
. With the new FileEntry object, you can copy the image to the file or do something else like upload it.
function createNewFileEntry(imgUri) {
window.resolveLocalFileSystemURL(cordova.file.cacheDirectory, function success(dirEntry) {
// JPEG file
dirEntry.getFile("tempFile.jpeg", { create: true, exclusive: false }, function (fileEntry) {
// Do something with it, like write to it, upload it, etc.
// writeFile(fileEntry, imgUri);
console.log("got file: " + fileEntry.fullPath);
// displayFileData(fileEntry.fullPath, "File copied to");
}, onErrorCreateFile);
}, onErrorResolveUrl);
}
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