我试图让我的应用程序为新的Android M权限更改做好准备，并发现了一些奇怪的行为。我的应用程序使用相机意图机制允许用户从相机获取图片。但是在另一个活动中需要使用具有Camera权限的相机本身（因为需要这个库依赖card.io）。
然而，当我尝试启动Camera意图时，只需要相机意图的活动中的M我看到以下崩溃（如果我从Manifest中删除了Camera权限，则不会发生这种情况），
> 09-25 21:57:55.260 774-8053/? I/ActivityManager: START u0
> {act=android.media.action.IMAGE_CAPTURE flg=0x3000003
> pkg=com.google.android.GoogleCamera
> cmp=com.google.android.GoogleCamera/com.android.camera.CaptureActivity
> (has clip) (has extras)} from uid 10098 on display 0 09-25
> 21:57:55.261 774-8053/? W/ActivityManager: Permission Denial: starting
> Intent { act=android.media.action.IMAGE_CAPTURE flg=0x3000003
> pkg=com.google.android.GoogleCamera
> cmp=com.google.android.GoogleCamera/com.android.camera.CaptureActivity
> (has clip) (has extras) } from null (pid=-1, uid=10098) with revoked
> permission android.permission.CAMERA 09-25 21:57:55.263 32657-32657/?
> E/ResolverActivity: Unable to launch as uid 10098 package
> com.example.me.mycamerselectapp, while running in android:ui 09-25
> 21:57:55.263 32657-32657/? E/ResolverActivity:
> java.lang.SecurityException: Permission Denial: starting Intent {
> act=android.media.action.IMAGE_CAPTURE flg=0x3000003
> pkg=com.google.android.GoogleCamera
> cmp=com.google.android.GoogleCamera/com.android.camera.CaptureActivity
> (has clip) (has extras) } from null (pid=-1, uid=10098) with revoked
> permission android.permission.CAMERA 09-25 21:57:55.263 32657-32657/?
> E/ResolverActivity: at
> android.os.Parcel.readException(Parcel.java:1599) 09-25 21:57:55.263
> 32657-32657/? E/ResolverActivity: at
> android.os.Parcel.readException(Parcel.java:1552) 09-25 21:57:55.263
> 32657-32657/? E/ResolverActivity: at
> android.app.ActivityManagerProxy.startActivityAsCaller(ActivityManagerNative.java:2730)
> 09-25 21:57:55.263 32657-32657/? E/ResolverActivity: at
> android.app.Instrumentation.execStartActivityAsCaller(Instrumentation.java:1725)
> 09-25 21:57:55.263 32657-32657/? E/ResolverActivity: at
> android.app.Activity.startActivityAsCaller(Activity.java:4047) 09-25
> 21:57:55.263 32657-32657/? E/ResolverActivity: at
> com.android.internal.app.ResolverActivity$DisplayResolveInfo.startAsCaller(ResolverActivity.java:983)
> 09-25 21:57:55.263 32657-32657/? E/ResolverActivity: at
> com.android.internal.app.ResolverActivity.safelyStartActivity(ResolverActivity.java:772)
> 09-25 21:57:55.263 32657-32657/? E/ResolverActivity: at
> com.android.internal.app.ResolverActivity.onTargetSelected(ResolverActivity.java:754)
> 09-25 21:57:55.263 32657-32657/? E/ResolverActivity: at
> com.android.internal.app.ChooserActivity.onTargetSelected(ChooserActivity.java:305)
> 09-25 21:57:55.263 32657-32657/? E/ResolverActivity: at
> com.android.internal.app.ResolverActivity.startSelected(ResolverActivity.java:603)
> 09-25 21:57:55.263 32657-32657/? E/ResolverActivity: at
> com.android.internal.app.ChooserActivity.startSelected(ChooserActivity.java:310)
> 09-25 21:57:55.263 32657-32657/? E/ResolverActivity: at
> com.android.internal.app.ChooserActivity$ChooserRowAdapter$2.onClick(ChooserActivity.java:990)
> 09-25 21:57:55.263 32657-32657/? E/ResolverActivity: at
> android.view.View.performClick(View.java:5198) 09-25 21:57:55.263
> 32657-32657/? E/ResolverActivity: at
> android.view.View$PerformClick.run(View.java:21147) 09-25 21:57:55.263
> 32657-32657/? E/ResolverActivity: at
> android.os.Handler.handleCallback(Handler.java:739) 09-25 21:57:55.263
> 32657-32657/? E/ResolverActivity: at
> android.os.Handler.dispatchMessage(Handler.java:95) 09-25 21:57:55.263
> 32657-32657/? E/ResolverActivity: at
> android.os.Looper.loop(Looper.java:148) 09-25 21:57:55.263
> 32657-32657/? E/ResolverActivity: at
> android.app.ActivityThread.main(ActivityThread.java:5417) 09-25
> 21:57:55.263 32657-32657/? E/ResolverActivity: at
> java.lang.reflect.Method.invoke(Native Method) 09-25 21:57:55.263
> 32657-32657/? E/ResolverActivity: at
> com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
> 09-25 21:57:55.263 32657-32657/? E/ResolverActivity: at
> com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616) 09-25
> 21:57:55.286 1159-1159/? I/Keyboard.Facilitator: onFinishInput() 09-25
> 21:57:55.297 32657-32676/? E/Surface: getSlotFromBufferLocked: unknown
> buffer: 0xaec352e0 09-25 21:57:55.344 325-349/? V/RenderScript:
> 0xb3693000 Launching thread(s), CPUs 4 09-25 21:57:57.290 325-349/?
> E/Surface: getSlotFromBufferLocked: unknown buffer: 0xb3f88240
这是Android M的已知问题吗？更重要的是，我该如何解决这个问题？
在清单中我有以下内容，
<uses-permission android:name="android.permission.CAMERA" />
这是我用来让用户用相机点击图片和/或选择图片的代码
public static Intent openImageIntent(Context context, Uri cameraOutputFile) {
// Camera.
final List<Intent> cameraIntents = new ArrayList<Intent>();
final Intent captureIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
final PackageManager packageManager = context.getPackageManager();
final List<ResolveInfo> listCam = packageManager.queryIntentActivities(captureIntent, 0);
for(ResolveInfo res : listCam) {
final String packageName = res.activityInfo.packageName;
final Intent intent = new Intent(captureIntent);
intent.setComponent(new ComponentName(res.activityInfo.packageName, res.activityInfo.name));
intent.setPackage(packageName);
intent.putExtra(MediaStore.EXTRA_OUTPUT, cameraOutputFile);
cameraIntents.add(intent);
}
// Filesystem.
final Intent galleryIntent = new Intent();
galleryIntent.setType("image/*");
galleryIntent.setAction(Intent.ACTION_GET_CONTENT);
// Chooser of filesystem options.
final Intent chooserIntent = Intent.createChooser(galleryIntent, "Take or select pic");
// Add the camera options.
chooserIntent.putExtra(Intent.EXTRA_INITIAL_INTENTS, cameraIntents.toArray(new Parcelable[]{}));
return chooserIntent;
}
我在活动中点击按钮调用openImageIntent()。当我在我的应用程序中没有CAMERA权限时，它可以正常工作，但添加后，我会收到上面发布的异常。
@Override
public void onClick(View v) {
Intent picCaptureIntenet = openImageIntent(MainActivity.this, getTempImageFileUri(MainActivity.this));
try {
startActivityForResult(picCaptureIntenet, 100);
} catch(Exception e) {
Toast.makeText(MainActivity.this, e.getMessage(), Toast.LENGTH_SHORT).show();
}
}
答案 0 :(得分：79)
我遇到了同样的问题，并从谷歌找到这个文档： https://developer.android.com/reference/android/provider/MediaStore.html#ACTION_IMAGE_CAPTURE
“注意：如果您的应用程序定位到M及以上，并声明为使用未授予的CAMERA权限，则尝试使用此操作将导致SecurityException。”
这真的很奇怪。 根本没有意义。 该应用程序声明使用具有IMAGE_CAPTURE操作的意图的Camera权限，只需运行SecurityException。但是，如果您的应用未使用意图使用动作声明相机权限IMAGE_CAPTURE可以毫无问题地启动相机应用。
解决方法是检查应用程序是否包含清单中的相机权限，如果是，请在启动意图之前请求相机权限。
以下是检查清单中是否包含权限的方法，无论是否授予权限都无关紧要。
public boolean hasPermissionInManifest(Context context, String permissionName) {
final String packageName = context.getPackageName();
try {
final PackageInfo packageInfo = context.getPackageManager()
.getPackageInfo(packageName, PackageManager.GET_PERMISSIONS);
final String[] declaredPermisisons = packageInfo.requestedPermissions;
if (declaredPermisisons != null && declaredPermisisons.length > 0) {
for (String p : declaredPermisisons) {
if (p.equals(permissionName)) {
return true;
}
}
}
} catch (NameNotFoundException e) {
}
return false;
}
答案 1 :(得分：20)
如果您使用的是Android M权限模型，则首先需要在运行时检查应用程序是否具有此权限，并且必须在运行时提示用户获取此权限。 您在清单上定义的权限不会在安装时自动授予。
if (checkSelfPermission(Manifest.permission.CAMERA)
!= PackageManager.PERMISSION_GRANTED) {
requestPermissions(new String[]{Manifest.permission.CAMERA},
MY_REQUEST_CODE);
}
MY_REQUEST_CODE是您可以定义的静态常量，它将再次用于requestPermission对话框回调。
您需要回调对话框结果：
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
if (requestCode == MY_REQUEST_CODE) {
if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// Now user should be able to use camera
}
else {
// Your app will not have this permission. Turn off all functions
// that require this permission or it will force close like your
// original question
}
}
}
修改
从堆栈跟踪中读取，看起来Google Camera没有启用CAMERA权限。毕竟，这可能看起来像是一种向后兼容的东西。
我们假设Google相机（或处理您的ACTION意图的任何其他应用程序）需要特定权限。
当您的应用没有CAMERA权限时，只需让Google相机使用旧版权模式即可。
但是，在您的清单中声明了CAMERA权限后，它还会强制使用Google相机（没有Android M权限模型）中的CAMERA权限来使用Android M权限模型（我认为。）
这意味着使用上述方法，您需要在运行时提供您的应用程序权限，这意味着它的子任务（在本例中为Google Camera）现在也具有该权限。
答案 2 :(得分：15)
至于你的问题'这是M中的一个已知问题吗？'谷歌开发人员回复了将此问题报告为错误的人。
以下是来自谷歌人的话：“这是为了避免用户挫败他们从应用程序撤销相机权限并且应用仍然能够通过意图拍摄照片的行为。用户不知道在许可撤销后拍摄的照片是通过不同的机制发生的，并且会质疑权限模型的正确性。这适用于MediaStore.ACTION_IMAGE_CAPTURE，MediaStore.ACTION_VIDEO_CAPTURE和Intent.ACTION_CALL文档，其中记录针对M的应用的行为更改。“
由于Google不介意从用户那里抽象出使用相机的机制，因此您可能会策略性地触发第一个相机权限请求，并引用使用相机作为请求推理的Activity的功能。如果您允许应用在用户只是尝试拍照时首先发出此权限请求，则用户可能会认为您的应用行为异常，因为拍摄照片通常不需要授予权限。
答案 3 :(得分：10)
如果您使用的是Google M，请转到设置 - ＆gt;应用 - ＆gt; 您的应用 - ＆gt;并给予适当的权限。
答案 4 :(得分：3)
我遇到了这个问题，我已经在使用JTY的答案了。问题是，在某些时候，“永不再问”再次检查了请求权限对话框。我正在开发SDK 24。
我处理权限的完整代码（在我的情况下是相机）如下：
public void checksCameraPermission(View view) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
Log.d("MyApp", "SDK >= 23");
if (this.checkSelfPermission(Manifest.permission.CAMERA)
!= PackageManager.PERMISSION_GRANTED) {
Log.d("MyApp", "Request permission");
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.CAMERA},
MY_REQUEST_CODE);
if (! shouldShowRequestPermissionRationale(Manifest.permission.CAMERA)) {
showMessageOKCancel("You need to allow camera usage",
new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
ActivityCompat.requestPermissions(FotoPerfil.this, new String[] {Manifest.permission.CAMERA},
MY_REQUEST_CODE);
}
});
}
}
else {
Log.d("MyApp", "Permission granted: taking pic");
takePicture();
}
}
else {
Log.d("MyApp", "Android < 6.0");
}
}
然后
private void showMessageOKCancel(String message, DialogInterface.OnClickListener okListener) {
new AlertDialog.Builder(this)
.setMessage(message)
.setPositiveButton("OK", okListener)
.setNegativeButton("Cancel", null)
.create()
.show();
}
然后
@Override
public void onRequestPermissionsResult(int requestCode,
String permissions[], int[] grantResults) {
switch (requestCode) {
case MY_REQUEST_CODE: {
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
criarFoto();
} else {
Toast.makeText(this, "You did not allow camera usage :(", Toast.LENGTH_SHORT).show();
noFotoTaken();
}
return;
}
}
}
预期的行为是，如果用户错误地选中了“永不再问”，您的应用程序会被卡住（请求对话框未显示），用户可能会感到沮丧。这样一条消息告诉他他需要这个权限。
答案 5 :(得分：0)
我删除了：
uses-permission android:name="android.permission.CAMERA"
并且只依赖于：
uses-feature android:name="android.hardware.camera" android:required="true"
。
答案 6 :(得分：0)
我的这种方法不仅仅检查Camera但我的应用程序在启动期间所需的所有权限...我在Helper.java文件中有这个，另请注意，对于我正在使用此库的对话框：{{3 }}
///check camera permission
public static boolean hasPermissions(final Activity activity){
//add your permissions here
String[] AppPermissions = {
Manifest.permission.CAMERA,
Manifest.permission.READ_EXTERNAL_STORAGE,
Manifest.permission.WRITE_EXTERNAL_STORAGE
};
//ungranted permissions
ArrayList<String> ungrantedPerms = new ArrayList<String>();
//loop
//lets set a boolean of hasUngrantedPerm to false
Boolean needsPermRequest = false;
//permissionGranted
int permGranted = PackageManager.PERMISSION_GRANTED;
//permission required content
String permRequestStr = activity.getString(R.string.the_following_perm_required);
//loop
for(String permission : AppPermissions){
//check if perm is granted
int checkPerm = ContextCompat.checkSelfPermission(activity,permission);
//if the permission is not granted
if(ContextCompat.checkSelfPermission(activity,permission) != permGranted){
needsPermRequest = true;
//add the permission to the ungranted permission list
ungrantedPerms.add(permission);
//permssion name
String[] splitPerm = permission.split(Pattern.quote("."));
String permName = splitPerm[splitPerm.length-1].concat("\n");
permRequestStr = permRequestStr.concat(permName);
}//end if
}//end loop
//if all permission is granted end exec
//then continue code exec
if(!needsPermRequest) {
return true;
}//end if
//convert array list to array string
final String[] ungrantedPermsArray = ungrantedPerms.toArray(new String[ungrantedPerms.size()]);
//show alert Dialog requesting permission
new MaterialDialog.Builder(activity)
.title(R.string.permission_required)
.content(permRequestStr)
.positiveText(R.string.enable)
.negativeText(R.string.cancel)
.onPositive(new MaterialDialog.SingleButtonCallback(){
@Override
public void onClick(@NonNull MaterialDialog dialog,@NonNull DialogAction which){
//request the permission now
ActivityCompat.requestPermissions(activity,ungrantedPermsArray,0);
}
})
.show();
//return false so that code exec in that script will not be allowed
//to continue
return false;
}//end checkPermissions
所以您将在此处添加或删除您的权限列表：
//add your permissions here
String[] AppPermissions = {
Manifest.permission.CAMERA,
Manifest.permission.READ_EXTERNAL_STORAGE,
Manifest.permission.WRITE_EXTERNAL_STORAGE
};
在我的活动文件中我检查了这样的权限，Helper类是我保存hasPermissions方法的地方
if(Helper.hasPermissions(this) == false){
return;
}//end if
意味着如果没有授予许可，我们不需要继续执行。 同样，我们需要在完成后收听权限请求，为此，将下面的代码添加到您的活动文件中（可选）
//Listen to Permission request completion
//put in your activity file
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults)
{
int permGranted = PackageManager.PERMISSION_GRANTED;
Boolean permissionRequired = false;
for(int perm : grantResults){
if(perm != permGranted){
permissionRequired = true;
}
}
//if permission is still required
if(permissionRequired){
//recheck and enforce permission again
Helper.hasPermissions(this);
}//end if
}//end method
答案 7 :(得分：0)
private static final int CAMERA_REQUEST_CODE = 10;
//TODO add camera opening functionality here.
try {
captureImage();
Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
startActivityForResult(intent,CAMERA_REQUEST_CODE);
} catch (Exception e){
e.printStackTrace();
}
private void captureImage(){
if( ContextCompat.checkSelfPermission(getContext(), android.Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
requestPermissions(new String[]{android.Manifest.permission.CAMERA},
CAMERA_REQUEST_CODE);
}
else {
// Open your camera here.
}
}
}
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
if (requestCode == CAMERA_REQUEST_CODE) {
if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// Now user should be able to use camera
}
else {
// Your app will not have this permission. Turn off all functions
// that require this permission or it will force close like your
// original question
}
}
}
P.S：确保不要复制粘贴被覆盖的方法。
答案 8 :(得分：0)
您必须启用“使用相机的应用程序”权限。我更喜欢添加此方法添加命令来激活相机：
public static async Task<bool> HasPermission()
{
var status = await CrossPermissions.Current.CheckPermissionStatusAsync(Permission.Camera);
if (status == PermissionStatus.Granted) return true;
if (await CrossPermissions.Current.ShouldShowRequestPermissionRationaleAsync(Permission.Camera))
{
ShowDialogOk("Error", "Please allow access to the camera.");//that is my custom method for allert
}
var results = await CrossPermissions.Current.RequestPermissionsAsync(Permission.Camera);
status = results[Permission.Camera];
return status == PermissionStatus.Granted;
}