三个类：
第一个核心类代码：（PermissionsManager.java）
import android.Manifest;
import android.app.Activity;
import android.content.Context;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.os.Build;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.app.ActivityCompat;
import android.support.v4.app.Fragment;
import android.util.Log;
import java.lang.ref.WeakReference;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
/**
* A class to help you manage your permissions simply.
*/
public class PermissionsManager {
private static final String TAG = PermissionsManager.class.getSimpleName();
private final Set<String> mPendingRequests = new HashSet<String>(1);
private final Set<String> mPermissions = new HashSet<String>(1);
private final List<WeakReference<PermissionsResultAction>> mPendingActions = new ArrayList<WeakReference<PermissionsResultAction>>(1);
private static PermissionsManager mInstance = null;
public static PermissionsManager getInstance() {
if (mInstance == null) {
mInstance = new PermissionsManager();
}
return mInstance;
}
private PermissionsManager() {
initializePermissionsMap();
}
/**
* This method uses reflection to read all the permissions in the Manifest class.
* This is necessary because some permissions do not exist on older versions of Android,
* since they do not exist, they will be denied when you check whether you have permission
* which is problematic since a new permission is often added where there was no previous
* permission required. We initialize a Set of available permissions and check the set
* when checking if we have permission since we want to know when we are denied a permission
* because it doesn't exist yet.
*/
private synchronized void initializePermissionsMap() {
Field[] fields = Manifest.permission.class.getFields();
for (Field field : fields) {
String name = null;
try {
name = (String) field.get("");
} catch (IllegalAccessException e) {
Log.e(TAG, "Could not access field", e);
}
mPermissions.add(name);
}
}
/**
* This method retrieves all the permissions declared in the application's manifest.
* It returns a non null array of permisions that can be declared.
*
* @param activity the Activity necessary to check what permissions we have.
* @return a non null array of permissions that are declared in the application manifest.
*/
@NonNull
private synchronized String[] getManifestPermissions(@NonNull final Activity activity) {
PackageInfo packageInfo = null;
List<String> list = new ArrayList<String>(1);
try {
Log.d(TAG, activity.getPackageName());
packageInfo = activity.getPackageManager().getPackageInfo(activity.getPackageName(), PackageManager.GET_PERMISSIONS);
} catch (PackageManager.NameNotFoundException e) {
Log.e(TAG, "A problem occurred when retrieving permissions", e);
}
if (packageInfo != null) {
String[] permissions = packageInfo.requestedPermissions;
if (permissions != null) {
for (String perm : permissions) {
Log.d(TAG, "Manifest contained permission: " + perm);
list.add(perm);
}
}
}
return list.toArray(new String[list.size()]);
}
/**
* This method adds the {@link PermissionsResultAction} to the current list
* of pending actions that will be completed when the permissions are
* received. The list of permissions passed to this method are registered
* in the PermissionsResultAction object so that it will be notified of changes
* made to these permissions.
*
* @param permissions the required permissions for the action to be executed.
* @param action the action to add to the current list of pending actions.
*/
private synchronized void addPendingAction(@NonNull String[] permissions,
@Nullable PermissionsResultAction action) {
if (action == null) {
return;
}
action.registerPermissions(permissions);
mPendingActions.add(new WeakReference<PermissionsResultAction>(action));
}
/**
* This method removes a pending action from the list of pending actions.
* It is used for cases where the permission has already been granted, so
* you immediately wish to remove the pending action from the queue and
* execute the action.
*
* @param action the action to remove
*/
private synchronized void removePendingAction(@Nullable PermissionsResultAction action) {
for (Iterator<WeakReference<PermissionsResultAction>> iterator = mPendingActions.iterator();
iterator.hasNext(); ) {
WeakReference<PermissionsResultAction> weakRef = iterator.next();
if (weakRef.get() == action || weakRef.get() == null) {
iterator.remove();
}
}
}
/**
* This static method can be used to check whether or not you have a specific permission.
* It is basically a less verbose method of using {@link ActivityCompat#checkSelfPermission(Context, String)}
* and will simply return a boolean whether or not you have the permission. If you pass
* in a null Context object, it will return false as otherwise it cannot check the permission.
* However, the Activity parameter is nullable so that you can pass in a reference that you
* are not always sure will be valid or not (e.g. getActivity() from Fragment).
*
* @param context the Context necessary to check the permission
* @param permission the permission to check
* @return true if you have been granted the permission, false otherwise
*/
@SuppressWarnings("unused")
public synchronized boolean hasPermission(@Nullable Context context, @NonNull String permission) {
return context != null && (ActivityCompat.checkSelfPermission(context, permission)
== PackageManager.PERMISSION_GRANTED || !mPermissions.contains(permission));
}
/**
* This static method can be used to check whether or not you have several specific permissions.
* It is simpler than checking using {@link ActivityCompat#checkSelfPermission(Context, String)}
* for each permission and will simply return a boolean whether or not you have all the permissions.
* If you pass in a null Context object, it will return false as otherwise it cannot check the
* permission. However, the Activity parameter is nullable so that you can pass in a reference
* that you are not always sure will be valid or not (e.g. getActivity() from Fragment).
*
* @param context the Context necessary to check the permission
* @param permissions the permissions to check
* @return true if you have been granted all the permissions, false otherwise
*/
@SuppressWarnings("unused")
public synchronized boolean hasAllPermissions(@Nullable Context context, @NonNull String[] permissions) {
if (context == null) {
return false;
}
boolean hasAllPermissions = true;
for (String perm : permissions) {
hasAllPermissions &= hasPermission(context, perm);
}
return hasAllPermissions;
}
/**
* This method will request all the permissions declared in your application manifest
* for the specified {@link PermissionsResultAction}. The purpose of this method is to enable
* all permissions to be requested at one shot. The PermissionsResultAction is used to notify
* you of the user allowing or denying each permission. The Activity and PermissionsResultAction
* parameters are both annotated Nullable, but this method will not work if the Activity
* is null. It is only annotated Nullable as a courtesy to prevent crashes in the case
* that you call this from a Fragment where {@link Fragment#getActivity()} could yield
* null. Additionally, you will not receive any notification of permissions being granted
* if you provide a null PermissionsResultAction.
*
* @param activity the Activity necessary to request and check permissions.
* @param action the PermissionsResultAction used to notify you of permissions being accepted.
*/
@SuppressWarnings("unused")
public synchronized void requestAllManifestPermissionsIfNecessary(final @Nullable Activity activity,
final @Nullable PermissionsResultAction action) {
if (activity == null) {
return;
}
String[] perms = getManifestPermissions(activity);
requestPermissionsIfNecessaryForResult(activity, perms, action);
}
/**
* This method should be used to execute a {@link PermissionsResultAction} for the array
* of permissions passed to this method. This method will request the permissions if
* they need to be requested (i.e. we don't have permission yet) and will add the
* PermissionsResultAction to the queue to be notified of permissions being granted or
* denied. In the case of pre-Android Marshmallow, permissions will be granted immediately.
* The Activity variable is nullable, but if it is null, the method will fail to execute.
* This is only nullable as a courtesy for Fragments where getActivity() may yeild null
* if the Fragment is not currently added to its parent Activity.
*
* @param activity the activity necessary to request the permissions.
* @param permissions the list of permissions to request for the {@link PermissionsResultAction}.
* @param action the PermissionsResultAction to notify when the permissions are granted or denied.
*/
@SuppressWarnings("unused")
public synchronized void requestPermissionsIfNecessaryForResult(@Nullable Activity activity,
@NonNull String[] permissions,
@Nullable PermissionsResultAction action) {
if (activity == null) {
return;
}
addPendingAction(permissions, action);
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) {
doPermissionWorkBeforeAndroidM(activity, permissions, action);
} else {
List<String> permList = getPermissionsListToRequest(activity, permissions, action);
if (permList.isEmpty()) {
//if there is no permission to request, there is no reason to keep the action int the list
removePendingAction(action);
} else {
String[] permsToRequest = permList.toArray(new String[permList.size()]);
mPendingRequests.addAll(permList);
ActivityCompat.requestPermissions(activity, permsToRequest, 1);
}
}
}
/**
* This method should be used to execute a {@link PermissionsResultAction} for the array
* of permissions passed to this method. This method will request the permissions if
* they need to be requested (i.e. we don't have permission yet) and will add the
* PermissionsResultAction to the queue to be notified of permissions being granted or
* denied. In the case of pre-Android Marshmallow, permissions will be granted immediately.
* The Fragment variable is used, but if {@link Fragment#getActivity()} returns null, this method
* will fail to work as the activity reference is necessary to check for permissions.
*
* @param fragment the fragment necessary to request the permissions.
* @param permissions the list of permissions to request for the {@link PermissionsResultAction}.
* @param action the PermissionsResultAction to notify when the permissions are granted or denied.
*/
@SuppressWarnings("unused")
public synchronized void requestPermissionsIfNecessaryForResult(@NonNull Fragment fragment,
@NonNull String[] permissions,
@Nullable PermissionsResultAction action) {
Activity activity = fragment.getActivity();
if (activity == null) {
return;
}
addPendingAction(permissions, action);
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) {
doPermissionWorkBeforeAndroidM(activity, permissions, action);
} else {
List<String> permList = getPermissionsListToRequest(activity, permissions, action);
if (permList.isEmpty()) {
//if there is no permission to request, there is no reason to keep the action int the list
removePendingAction(action);
} else {
String[] permsToRequest = permList.toArray(new String[permList.size()]);
mPendingRequests.addAll(permList);
fragment.requestPermissions(permsToRequest, 1);
}
}
}
/**
* This method notifies the PermissionsManager that the permissions have change. If you are making
* the permissions requests using an Activity, then this method should be called from the
* Activity callback onRequestPermissionsResult() with the variables passed to that method. If
* you are passing a Fragment to make the permissions request, then you should call this in
* the {@link Fragment#onRequestPermissionsResult(int, String[], int[])} method.
* It will notify all the pending PermissionsResultAction objects currently
* in the queue, and will remove the permissions request from the list of pending requests.
*
* @param permissions the permissions that have changed.
* @param results the values for each permission.
*/
@SuppressWarnings("unused")
public synchronized void notifyPermissionsChange(@NonNull String[] permissions, @NonNull int[] results) {
int size = permissions.length;
if (results.length < size) {
size = results.length;
}
Iterator<WeakReference<PermissionsResultAction>> iterator = mPendingActions.iterator();
while (iterator.hasNext()) {
PermissionsResultAction action = iterator.next().get();
for (int n = 0; n < size; n++) {
if (action == null || action.onResult(permissions[n], results[n])) {
iterator.remove();
break;
}
}
}
for (int n = 0; n < size; n++) {
mPendingRequests.remove(permissions[n]);
}
}
/**
* When request permissions on devices before Android M (Android 6.0, API Level 23)
* Do the granted or denied work directly according to the permission status
*
* @param activity the activity to check permissions
* @param permissions the permissions names
* @param action the callback work object, containing what we what to do after
* permission check
*/
private void doPermissionWorkBeforeAndroidM(@NonNull Activity activity,
@NonNull String[] permissions,
@Nullable PermissionsResultAction action) {
for (String perm : permissions) {
if (action != null) {
if (!mPermissions.contains(perm)) {
action.onResult(perm, Permissions.NOT_FOUND);
} else if (ActivityCompat.checkSelfPermission(activity, perm)
!= PackageManager.PERMISSION_GRANTED) {
action.onResult(perm, Permissions.DENIED);
} else {
action.onResult(perm, Permissions.GRANTED);
}
}
}
}
/**
* Filter the permissions list:
* If a permission is not granted, add it to the result list
* if a permission is granted, do the granted work, do not add it to the result list
*
* @param activity the activity to check permissions
* @param permissions all the permissions names
* @param action the callback work object, containing what we what to do after
* permission check
* @return a list of permissions names that are not granted yet
*/
@NonNull
private List<String> getPermissionsListToRequest(@NonNull Activity activity,
@NonNull String[] permissions,
@Nullable PermissionsResultAction action) {
List<String> permList = new ArrayList<String>(permissions.length);
for (String perm : permissions) {
if (!mPermissions.contains(perm)) {
if (action != null) {
action.onResult(perm, Permissions.NOT_FOUND);
}
} else if (ActivityCompat.checkSelfPermission(activity, perm) != PackageManager.PERMISSION_GRANTED) {
if (!mPendingRequests.contains(perm)) {
permList.add(perm);
}
} else {
if (action != null) {
action.onResult(perm, Permissions.GRANTED);
}
}
}
return permList;
}
}第二个类核心代码：（PermissionsResultAction.java）
import android.content.pm.PackageManager;
import android.os.Handler;
import android.os.Looper;
import android.support.annotation.CallSuper;
import android.support.annotation.NonNull;
import android.util.Log;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
/**
* This abstract class should be used to create an if/else action that the PermissionsManager
* can execute when the permissions you request are granted or denied. Simple use involves
* creating an anonymous instance of it and passing that instance to the
* requestPermissionsIfNecessaryForResult method. The result will be sent back to you as
* either onGranted (all permissions have been granted), or onDenied (a required permission
* has been denied). Ideally you put your functionality in the onGranted method and notify
* the user what won't work in the onDenied method.
*/
public abstract class PermissionsResultAction {
private static final String TAG = PermissionsResultAction.class.getSimpleName();
private final Set<String> mPermissions = new HashSet<String>(1);
private Looper mLooper = Looper.getMainLooper();
/**
* Default Constructor
*/
public PermissionsResultAction() {}
/**
* Alternate Constructor. Pass the looper you wish the PermissionsResultAction
* callbacks to be executed on if it is not the current Looper. For instance,
* if you are making a permissions request from a background thread but wish the
* callback to be on the UI thread, use this constructor to specify the UI Looper.
*
* @param looper the looper that the callbacks will be called using.
*/
@SuppressWarnings("unused")
public PermissionsResultAction(@NonNull Looper looper) {mLooper = looper;}
/**
* This method is called when ALL permissions that have been
* requested have been granted by the user. In this method
* you should put all your permissions sensitive code that can
* only be executed with the required permissions.
*/
public abstract void onGranted();
/**
* This method is called when a permission has been denied by
* the user. It provides you with the permission that was denied
* and will be executed on the Looper you pass to the constructor
* of this class, or the Looper that this object was created on.
*
* @param permission the permission that was denied.
*/
public abstract void onDenied(String permission);
/**
* This method is used to determine if a permission not
* being present on the current Android platform should
* affect whether the PermissionsResultAction should continue
* listening for events. By default, it returns true and will
* simply ignore the permission that did not exist. Usually this will
* work fine since most new permissions are introduced to
* restrict what was previously allowed without permission.
* If that is not the case for your particular permission you
* request, override this method and return false to result in the
* Action being denied.
*
* @param permission the permission that doesn't exist on this
* Android version
* @return return true if the PermissionsResultAction should
* ignore the lack of the permission and proceed with exection
* or false if the PermissionsResultAction should treat the
* absence of the permission on the API level as a denial.
*/
@SuppressWarnings({"WeakerAccess", "SameReturnValue"})
public synchronized boolean shouldIgnorePermissionNotFound(String permission) {
Log.d(TAG, "Permission not found: " + permission);
return true;
}
@SuppressWarnings("WeakerAccess")
@CallSuper
protected synchronized final boolean onResult(final @NonNull String permission, int result) {
if (result == PackageManager.PERMISSION_GRANTED) {
return onResult(permission, Permissions.GRANTED);
} else {
return onResult(permission, Permissions.DENIED);
}
}
/**
* This method is called when a particular permission has changed.
* This method will be called for all permissions, so this method determines
* if the permission affects the state or not and whether it can proceed with
* calling onGranted or if onDenied should be called.
*
* @param permission the permission that changed.
* @param result the result for that permission.
* @return this method returns true if its primary action has been completed
* and it should be removed from the data structure holding a reference to it.
*/
@SuppressWarnings("WeakerAccess")
@CallSuper
protected synchronized final boolean onResult(final @NonNull String permission, Permissions result) {
mPermissions.remove(permission);
if (result == Permissions.GRANTED) {
if (mPermissions.isEmpty()) {
new Handler(mLooper).post(new Runnable() {
@Override
public void run() {
onGranted();
}
});
return true;
}
} else if (result == Permissions.DENIED) {
new Handler(mLooper).post(new Runnable() {
@Override
public void run() {
onDenied(permission);
}
});
return true;
} else if (result == Permissions.NOT_FOUND) {
if (shouldIgnorePermissionNotFound(permission)) {
if (mPermissions.isEmpty()) {
new Handler(mLooper).post(new Runnable() {
@Override
public void run() {
onGranted();
}
});
return true;
}
} else {
new Handler(mLooper).post(new Runnable() {
@Override
public void run() {
onDenied(permission);
}
});
return true;
}
}
return false;
}
/**
* This method registers the PermissionsResultAction object for the specified permissions
* so that it will know which permissions to look for changes to. The PermissionsResultAction
* will then know to look out for changes to these permissions.
*
* @param perms the permissions to listen for
*/
@SuppressWarnings("WeakerAccess")
@CallSuper
protected synchronized final void registerPermissions(@NonNull String[] perms) {
Collections.addAll(mPermissions, perms);
}
}enum Permissions {
GRANTED,
DENIED,
NOT_FOUND
}已拍照和读取内存卡权限为例
申请权限的代码：
//todo 头像设置
PermissionsManager.getInstance().requestPermissionsIfNecessaryForResult(MainActivity.this, new String[]{Manifest.permission.CAMERA, Manifest.permission.WRITE_EXTERNAL_STORAGE},
new PermissionsResultAction() {
@Override
public void onGranted() {
//弹框，具体逻辑处理
HeadPortraitUtil.showHeadPortraitDialog(MainActivity.this);
}
@Override
public void onDenied(String permission) {
if (permission.equals("android.permission.CAMERA")) {
Toast.makeText(MainActivity.this, "该功能需要获取拍照权限。", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(MainActivity.this, "该功能需要获取读取内存卡权限。", Toast.LENGTH_SHORT).show();
}
}
}); //权限申请回调
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
PermissionsManager.getInstance().notifyPermissionsChange(permissions, grantResults);
}