我试图拍摄一张照片，然后使用这张照片。以下是我的操作步骤：
我的设备是Nexus 6P (Android 7.1.1)。
首先，我创建了一个Uri：
Uri mPicPath = UriUtil.fromFile(this, UriUtil.createTmpFileForPic());
//Uri mPicPath = UriUtil.fromFile(this, UriUtil.createFileForPic());
然后，我开始使用 Intent：
Intent intent = ActivityUtils.getTakePicIntent(mPicPath);
if (intent.resolveActivity(getPackageManager()) != null) {
startActivityForResult(intent, RequestCode.TAKE_PIC);
}
最后，我在onActivityResult中处理了这个Uri：
if (requestCode == RequestCode.TAKE_PIC) {
if (resultCode == RESULT_OK && mPicPath != null) {
Bitmap requireBitmap = BitmapFactory.decodeFile(mPicPath.getPath());
//path is like this: /Download/Android/data/{@applicationId}/files/Pictures/JPEG_20170216_173121268719051242.jpg
requireBitmap.recycle();//Here NPE was thrown.
}
}
同时，这里是UriUtil：
public class UriUtil {
public static File createFileForPic() throws IOException {
String fileName = "JPEG_" + new SimpleDateFormat("yyyyMMdd_HHmmssSSS", Locale.getDefault()).format(new Date()) + ".jpg";
File storageDic = SPApplication.getInstance().getExternalFilesDir(Environment.DIRECTORY_PICTURES);
return new File(storageDic, fileName);
}
public static File createTmpFileForPic() throws IOException {
String fileName = "JPEG_" + new SimpleDateFormat("yyyyMMdd_HHmmssSSS", Locale.getDefault()).format(new Date());
File storageDic = SPApplication.getInstance().getExternalFilesDir(Environment.DIRECTORY_PICTURES);
return File.createTempFile(fileName, ".jpg", storageDic);
}
public static Uri fromFile(@NonNull Context context, @NonNull File file) {
if (context == null || file == null) {
throw new RuntimeException("context or file can't be null");
}
if (ActivityUtils.requireSDKInt(Build.VERSION_CODES.N)) {
return FileProvider.getUriForFile(context, BuildConfig.APPLICATION_ID + ".file_provider", file);
} else {
return Uri.fromFile(file);
}
}
}
还有 getTakePicIntent(Uri):
public static Intent getTakePicIntent(Uri mPicPath) {
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
intent.putExtra(MediaStore.EXTRA_OUTPUT, mPicPath);
if (!ActivityUtils.requireSDKInt(Build.VERSION_CODES.KITKAT_WATCH)) {//in pre-KitKat devices, manually grant uri permission.
List<ResolveInfo> resInfoList = SPApplication.getInstance().getPackageManager().queryIntentActivities(intent, PackageManager.MATCH_DEFAULT_ONLY);
for (ResolveInfo resolveInfo : resInfoList) {
String packageName = resolveInfo.activityInfo.packageName;
SPApplication.getInstance().grantUriPermission(packageName, mPicPath, Intent.FLAG_GRANT_WRITE_URI_PERMISSION | Intent.FLAG_GRANT_READ_URI_PERMISSION);
}
} else {
intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
intent.addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
}
return intent;
}
并且 requireSDKInt：
public static boolean requireSDKInt(int sdkInt) {
return Build.VERSION.SDK_INT >= sdkInt;
}
除了Android Nougat（7.x.x）之外，各种不同的Android API都可以正常工作。即使提供了“FileProvider”，“requireBitmap”始终返回为“null”。
在阅读日志后，从“BitmapFactory”中抛出了“FileNotFoundException”。就像这样：
BitmapFactory: Unable to decode stream: java.io.FileNotFoundException: /Download/Android/data/{@applicationId}/files/Pictures/JPEG_20170216_1744551601425984925.jpg (No such file or directory)
看起来一切都很清楚，但我仍然不理解。
怎么会这样？明明我创建了一个文件！我该怎么解决呢？有什么想法吗？
File.createTempFile。不要创建临时文件，只需创建文件名即可。该文件将由相机应用程序创建。 - greenappsUri mPicPath和mUri.getPath())？？？？？mUri 是从哪里来的？ - greenappsstorageDic目录是否存在。完整路径永远不能以 /Download/... 开头。SPApplication.getInstance().getExternalFilesDir()的实现有误。 - greenapps