cordova-plugin-camera-dev/doc/index.md
2014-11-06 17:34:12 -05:00

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# org.apache.cordova.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
cordova plugin add org.apache.cordova.camera
## navigator.camera.getPicture
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 method
itself returns a `CameraPopoverHandle` object that can be used to
reposition the file selection popover.
navigator.camera.getPicture( cameraSuccess, cameraError, cameraOptions );
### Description
The `camera.getPicture` function opens the device's default camera
application that allows users to snap pictures. This behavior occurs
by default, 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 below
- Save the data locally (`LocalStorage`, [Lawnchair](http://brianleroux.github.com/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
- Amazon Fire OS
- Android
- BlackBerry 10
- Browser
- Firefox OS
- iOS
- Tizen
- Windows Phone 7 and 8
- Windows 8
### 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 image may not appear when the Cordova activity is restored.
### Browser Quirks
Can only return photos as base64-encoded image.
### Firefox OS Quirks
Camera plugin is currently implemented using [Web Activities](https://hacks.mozilla.org/2013/01/introducing-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`.
### Example
Take a photo and retrieve it as a base64-encoded image:
navigator.camera.getPicture(onSuccess, onFail, { quality: 50,
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);
}
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);
}
## CameraOptions
Optional parameters to customize the camera settings.
{ quality : 75,
destinationType : Camera.DestinationType.DATA_URL,
sourceType : Camera.PictureSourceType.CAMERA,
allowEdit : true,
encodingType: Camera.EncodingType.JPEG,
targetWidth: 100,
targetHeight: 100,
popoverOptions: CameraPopoverOptions,
saveToPhotoAlbum: false };
### Options
- __quality__: Quality of the saved image, expressed as a range of 0-100, where 100 is typically full resolution with no loss from file compression. The default is 50. _(Number)_ (Note that information about the camera's resolution is unavailable.)
- __destinationType__: Choose the format of the return value. The default is FILE_URI. Defined in `navigator.camera.DestinationType` _(Number)_
Camera.DestinationType = {
DATA_URL : 0, // Return image as base64-encoded string
FILE_URI : 1, // Return image file URI
NATIVE_URI : 2 // Return image native URI (e.g., assets-library:// on iOS or content:// on Android)
};
- __sourceType__: Set the source of the picture. The default is CAMERA. Defined in `navigator.camera.PictureSourceType` _(Number)_
Camera.PictureSourceType = {
PHOTOLIBRARY : 0,
CAMERA : 1,
SAVEDPHOTOALBUM : 2
};
- __allowEdit__: Allow simple editing of image before selection. _(Boolean)_
- __encodingType__: Choose the returned image file's encoding. Default is JPEG. Defined in `navigator.camera.EncodingType` _(Number)_
Camera.EncodingType = {
JPEG : 0, // Return JPEG encoded image
PNG : 1 // Return PNG encoded image
};
- __targetWidth__: Width in pixels to scale image. Must be used with __targetHeight__. Aspect ratio remains constant. _(Number)_
- __targetHeight__: Height in pixels to scale image. Must be used with __targetWidth__. Aspect ratio remains constant. _(Number)_
- __mediaType__: Set the type of media to select from. Only works when `PictureSourceType` is `PHOTOLIBRARY` or `SAVEDPHOTOALBUM`. Defined in `nagivator.camera.MediaType` _(Number)_
Camera.MediaType = {
PICTURE: 0, // allow selection of still pictures only. DEFAULT. Will return format specified via DestinationType
VIDEO: 1, // allow selection of video only, WILL ALWAYS RETURN FILE_URI
ALLMEDIA : 2 // allow selection from all media types
};
- __correctOrientation__: Rotate the image to correct for the orientation of the device during capture. _(Boolean)_
- __saveToPhotoAlbum__: Save the image to the photo album on the device after capture. _(Boolean)_
- __popoverOptions__: iOS-only options that specify popover location in iPad. Defined in `CameraPopoverOptions`.
- __cameraDirection__: Choose the camera to use (front- or back-facing). The default is BACK. Defined in `navigator.camera.Direction` _(Number)_
Camera.Direction = {
BACK : 0, // Use the back-facing camera
FRONT : 1 // Use the front-facing camera
};
### Amazon Fire OS Quirks
- Any `cameraDirection` value results in a back-facing photo.
- Ignores the `allowEdit` parameter.
- `Camera.PictureSourceType.PHOTOLIBRARY` and `Camera.PictureSourceType.SAVEDPHOTOALBUM` both display the same photo album.
### Android Quirks
- Any `cameraDirection` value results in a back-facing photo.
- Ignores the `allowEdit` parameter.
- `Camera.PictureSourceType.PHOTOLIBRARY` and `Camera.PictureSourceType.SAVEDPHOTOALBUM` both display the same photo album.
### 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 equals `1` (image file URI)
- Ignores the `allowEdit` parameter.
- Ignores the `PictureSourceType` parameter (user chooses it in a dialog window)
- Ignores the `encodingType`
- Ignores the `targetWidth` and `targetHeight`
- `Camera.MediaType` is not supported.
- Ignores the `correctOrientation` parameter.
- Ignores the `cameraDirection` parameter.
### iOS Quirks
- Set `quality` below 50 to avoid memory errors on some devices.
- 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.
### 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 wp7/8 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 a blocker for your application, you will need to implement the CameraCaptureTask as documented on msdn : [http://msdn.microsoft.com/en-us/library/windowsphone/develop/hh394006.aspx](http://msdn.microsoft.com/en-us/library/windowsphone/develop/hh394006.aspx)
You may also comment or up-vote the related issue in the [issue tracker](https://issues.apache.org/jira/browse/CB-2083)
- Ignores the `mediaType` property of `cameraOptions` as the Windows Phone SDK does not provide a way to choose videos from PHOTOLIBRARY.
## CameraError
onError callback function that provides an error message.
function(message) {
// Show a helpful message
}
### Parameters
- __message__: The message is provided by the device's native code. _(String)_
## cameraSuccess
onSuccess callback function that provides the image data.
function(imageData) {
// Do something with the image
}
### Parameters
- __imageData__: Base64 encoding of the image data, _or_ the image file URI, depending on `cameraOptions` in effect. _(String)_
### Example
// Show image
//
function cameraCallback(imageData) {
var image = document.getElementById('myImage');
image.src = "data:image/jpeg;base64," + imageData;
}
## CameraPopoverHandle
A handle to the popover dialog created by `navigator.camera.getPicture`.
### Methods
- __setPosition__: Set the position of the popover.
### Supported Platforms
- iOS
### setPosition
Set the position of the popover.
__Parameters__:
- `cameraPopoverOptions`: the `CameraPopoverOptions` that specify the new position
### 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);
}
## 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.
{ x : 0,
y : 32,
width : 320,
height : 480,
arrowDir : Camera.PopoverArrowDirection.ARROW_ANY
};
### CameraPopoverOptions
- __x__: x pixel coordinate of screen element onto which to anchor the popover. _(Number)_
- __y__: y pixel coordinate of screen element onto which to anchor the popover. _(Number)_
- __width__: width, in pixels, of the screen element onto which to anchor the popover. _(Number)_
- __height__: height, in pixels, of the screen element onto which to anchor the popover. _(Number)_
- __arrowDir__: Direction the arrow on the popover should point. Defined in `Camera.PopoverArrowDirection` _(Number)_
Camera.PopoverArrowDirection = {
ARROW_UP : 1, // matches iOS UIPopoverArrowDirection constants
ARROW_DOWN : 2,
ARROW_LEFT : 4,
ARROW_RIGHT : 8,
ARROW_ANY : 15
};
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.
## navigator.camera.cleanup
Removes intermediate photos taken by the camera from temporary
storage.
navigator.camera.cleanup( cameraSuccess, cameraError );
### Description
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
### Example
navigator.camera.cleanup(onSuccess, onFail);
function onSuccess() {
console.log("Camera cleanup success.")
}
function onFail(message) {
alert('Failed because: ' + message);
}