我有意向通过打开相机拍照的程序。 这重要的一部分工作正常了。 不过,我希望它保存到特定的文件夹与某个文件名(文件名是可选的,但它会真的帮助)。
因此,这里是我到目前为止所。
下面是代码,打开相机行:
//TODO camera stuff.
Intent openCam = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
//The two lines of code below were commented out at first.
//They were eventually added when I tried to save it with a custom name and destination
fileUri = getOutputMediaFileUri(MEDIA_TYPE_IMAGE); // create a file to save the image
openCam.putExtra(MediaStore.EXTRA_OUTPUT, fileUri); // set the image file name
startActivityForResult(openCam, CAPTURE_IMAGE_ACTIVITY_REQUEST_CODE);
结果处理放在这里:
//TODO handle result
if (requestCode == CAPTURE_IMAGE_ACTIVITY_REQUEST_CODE) {
if (resultCode == RESULT_OK) {
// Image captured and saved to fileUri specified in the Intent
Toast.makeText(this, "Image saved to:\n" +
data.getData(), Toast.LENGTH_LONG).show();
System.out.println("I am here");
}
else if (resultCode == RESULT_CANCELED) {
// User cancelled the image capture
}
else {
// Image capture failed, advise user
}
}
之前我实现下面的两种方法,代码是工作的罚款。 然而,它被保存到使用默认的文件名(时间戳版本)的默认文件夹。 显示吐司“成像保存到:空”,因为我没有设置这部分呢。
因此,这里有它们被认为可以处理自定义文件名和目的地的方法
/** Create a file Uri for saving an image or video */
private static Uri getOutputMediaFileUri(int type){
return Uri.fromFile(getOutputMediaFile(type));
}
/** Create a File for saving an image or video */
private static File getOutputMediaFile(int type){
// To be safe, you should check that the SDCard is mounted
// using Environment.getExternalStorageState() before doing this.
Environment.getExternalStorageState();
File mediaStorageDir = new File(Environment.getExternalStoragePublicDirectory(
Environment.DIRECTORY_PICTURES), "MyCameraApp");
// This location works best if you want the created images to be shared
// between applications and persist after your app has been uninstalled.
// Create the storage directory if it does not exist
if (! mediaStorageDir.exists()){
if (! mediaStorageDir.mkdirs()){
Log.d("MyCameraApp", "failed to create directory");
return null;
}
}
// Create a media file name
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
File mediaFile;
if (type == MEDIA_TYPE_IMAGE){
mediaFile = new File(mediaStorageDir.getPath() + File.separator +
"IMG_"+ timeStamp + ".jpg");
} else {
return null;
}
return mediaFile;
}
*这些代码是从developer.android.com相机指南解除。
上面的代码管理打开摄像头,拍照并保存。 但是,当用户决定停止拍照,然后按返回键出现问题。 什么情况是,该应用程序强制关闭给这个错误:
10-21 12:44:33.699: E/AndroidRuntime(13016): FATAL EXCEPTION: main
10-21 12:44:33.699: E/AndroidRuntime(13016): java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=100, result=-1, data=null} to activity {com.AIC.QRCodeScanner/com.AIC.QRCodeScanner.QRCodeScanner}: java.lang.NullPointerException
10-21 12:44:33.699: E/AndroidRuntime(13016): at android.app.ActivityThread.deliverResults(ActivityThread.java:2536)
10-21 12:44:33.699: E/AndroidRuntime(13016): at android.app.ActivityThread.handleSendResult(ActivityThread.java:2578)
10-21 12:44:33.699: E/AndroidRuntime(13016): at android.app.ActivityThread.access$2000(ActivityThread.java:117)
10-21 12:44:33.699: E/AndroidRuntime(13016): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:965)
10-21 12:44:33.699: E/AndroidRuntime(13016): at android.os.Handler.dispatchMessage(Handler.java:99)
10-21 12:44:33.699: E/AndroidRuntime(13016): at android.os.Looper.loop(Looper.java:123)
10-21 12:44:33.699: E/AndroidRuntime(13016): at android.app.ActivityThread.main(ActivityThread.java:3691)
10-21 12:44:33.699: E/AndroidRuntime(13016): at java.lang.reflect.Method.invokeNative(Native Method)
10-21 12:44:33.699: E/AndroidRuntime(13016): at java.lang.reflect.Method.invoke(Method.java:507)
10-21 12:44:33.699: E/AndroidRuntime(13016): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:847)
10-21 12:44:33.699: E/AndroidRuntime(13016): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:605)
10-21 12:44:33.699: E/AndroidRuntime(13016): at dalvik.system.NativeStart.main(Native Method)
10-21 12:44:33.699: E/AndroidRuntime(13016): Caused by: java.lang.NullPointerException
10-21 12:44:33.699: E/AndroidRuntime(13016): at com.AIC.QRCodeScanner.QRCodeScanner.onActivityResult(QRCodeScanner.java:379)
10-21 12:44:33.699: E/AndroidRuntime(13016): at android.app.Activity.dispatchActivityResult(Activity.java:3934)
10-21 12:44:33.699: E/AndroidRuntime(13016): at android.app.ActivityThread.deliverResults(ActivityThread.java:2532)
10-21 12:44:33.699: E/AndroidRuntime(13016):
... 11 more
该生产线是指向将是此行(行379): data.getData(), Toast.LENGTH_LONG
然而,这些文件都保存在文件夹/Pictures/MyCameraApp
与拍摄的照片的Instagram一起。
所以问题是:1,有没有一种方法,使onActivityResult正常工作? 我知道我可以诉诸为了不杀应用程序中使用startActivity。 2.有没有办法只能拿一个相机所拍摄? 因此,用户保存的照片后,应用程序可以追溯到主要活动。 3.另外,我可以将它保存到我自己的文件夹? 我不知道为什么它会保存照片/Pictures/MyCameraApp
,我希望它只保存到/MyCameraApp
。
我想我错过了简单的东西在这里。