Fix bug WRITE_EXTERNAL_STORAGE permission missing

app/src/main/AndroidManifest.xml

@@ -4,8 +4,7 @@
 
     <uses-permission android:name="android.permission.INTERNET" />
     <uses-permission android:name="com.google.android.c2dm.permission.RECEIVE" />
-    <uses-permission android:name="android.permission.USE_CREDENTIALS" />
-    <uses-permission android:name="android.permission.GET_ACCOUNTS" />
+    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
 
     <permission
         android:name="${applicationId}.permission.C2D_MESSAGE"

app/src/main/java/com/xfrocks/api/androiddemo/common/AndroidPermissions.java

@@ -0,0 +1,69 @@
+package com.xfrocks.api.androiddemo.common;
+
+import android.content.Context;
+import android.content.pm.PackageManager;
+import android.os.Build;
+import android.support.v4.app.Fragment;
+import android.support.v4.content.ContextCompat;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+public class AndroidPermissions {
+    // https://gist.github.com/gotev/67c300c563bdf68a502c
+
+    private final Context mContext;
+    private final String[] mRequiredPermissions;
+    private final ArrayList<String> mPermissionsToRequest = new ArrayList<>();
+
+    public AndroidPermissions(Context context, String... requiredPermissions) {
+        mContext = context;
+        mRequiredPermissions = requiredPermissions;
+    }
+
+    public boolean needRequesting() {
+        if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.LOLLIPOP_MR1) {
+            return false;
+        }
+
+        mPermissionsToRequest.clear();
+
+        for (String permission : mRequiredPermissions) {
+            if (ContextCompat.checkSelfPermission(mContext, permission) != PackageManager.PERMISSION_GRANTED) {
+                mPermissionsToRequest.add(permission);
+            }
+        }
+
+        return !mPermissionsToRequest.isEmpty();
+
+    }
+
+    public void requestPermissions(Fragment fragment, int requestCode) {
+        String[] permissions = mPermissionsToRequest.toArray(new String[mPermissionsToRequest.size()]);
+        fragment.requestPermissions(permissions, requestCode);
+    }
+
+    public boolean areAllRequiredPermissionsGranted(String[] permissions, int[] grantResults) {
+        if (permissions == null || permissions.length == 0
+                || grantResults == null || grantResults.length == 0) {
+            return false;
+        }
+
+        LinkedHashMap<String, Integer> perms = new LinkedHashMap<>();
+
+        for (int i = 0; i < permissions.length; i++) {
+            if (!perms.containsKey(permissions[i])
+                    || (perms.containsKey(permissions[i]) && perms.get(permissions[i]) == PackageManager.PERMISSION_DENIED))
+                perms.put(permissions[i], grantResults[i]);
+        }
+
+        for (Map.Entry<String, Integer> entry : perms.entrySet()) {
+            if (entry.getValue() != PackageManager.PERMISSION_GRANTED) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+}

app/src/main/java/com/xfrocks/api/androiddemo/common/ArrayUtils.java

@@ -2,7 +2,7 @@
 
 import java.lang.reflect.Array;
 
-public class ArrayUtils {
+class ArrayUtils {
     public static <T> T[] concat(T[] first, T[] second, Class<T> type) {
         int len1 = first.length;
         int len2 = second.length;

app/src/main/java/com/xfrocks/api/androiddemo/common/ReflectionUtils.java

@@ -5,7 +5,7 @@
 
 import java.lang.reflect.Field;
 
-public class ReflectionUtils {
+class ReflectionUtils {
 
     public static Field[] getFieldsUpTo(@NonNull Class<?> type, @Nullable Class<?> exclusiveParent) {
         // https://github.com/dancerjohn/LibEx/blob/master/libex/src/main/java/org/libex/reflect/ReflectionUtils.java

app/src/main/java/com/xfrocks/api/androiddemo/discussion/QuickReplyFragment.java

@@ -1,11 +1,13 @@
 package com.xfrocks.api.androiddemo.discussion;
 
+import android.Manifest;
 import android.app.Activity;
 import android.content.Context;
 import android.content.Intent;
 import android.graphics.Bitmap;
 import android.net.Uri;
 import android.os.Bundle;
+import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.support.v4.app.Fragment;
 import android.support.v7.widget.LinearLayoutManager;
@@ -27,6 +29,7 @@
 import com.bumptech.glide.request.target.SimpleTarget;
 import com.xfrocks.api.androiddemo.App;
 import com.xfrocks.api.androiddemo.R;
+import com.xfrocks.api.androiddemo.common.AndroidPermissions;
 import com.xfrocks.api.androiddemo.common.ApiConstants;
 import com.xfrocks.api.androiddemo.common.ChooserIntent;
 import com.xfrocks.api.androiddemo.common.model.ApiAccessToken;
@@ -48,6 +51,8 @@
 public class QuickReplyFragment extends Fragment {
 
     private static final int RC_PICK_FILE = 1;
+    private static final int RC_ATTEMPT_ATTACH = 2;
+    private static final int RC_ATTEMPT_CAMERA = 3;
 
     private LinearLayout mExtra;
     private ImageButton mAttach;
@@ -58,9 +63,17 @@ public class QuickReplyFragment extends Fragment {
     private ApiDiscussion mDiscussion;
     private Listener mListener;
 
+    private AndroidPermissions mUploadPermissions;
     private AttachmentsAdapter mPendingAttachments;
     private String mPendingMessage;
 
+    @Override
+    public void onCreate(@Nullable Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+
+        mUploadPermissions = new AndroidPermissions(getContext(), Manifest.permission.WRITE_EXTERNAL_STORAGE);
+    }
+
     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
@@ -137,6 +150,24 @@ public void onActivityResult(int requestCode, int resultCode, Intent data) {
         }
     }
 
+    @Override
+    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
+        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
+
+        switch (requestCode) {
+            case RC_ATTEMPT_ATTACH:
+                if (mUploadPermissions.areAllRequiredPermissionsGranted(permissions, grantResults)) {
+                    attemptAttachStep2();
+                }
+                break;
+            case RC_ATTEMPT_CAMERA:
+                if (mUploadPermissions.areAllRequiredPermissionsGranted(permissions, grantResults)) {
+                    attemptCameraStep2();
+                }
+                break;
+        }
+    }
+
     void setup(ApiDiscussion discussion, Listener listener) {
         mDiscussion = discussion;
         mListener = listener;
@@ -210,11 +241,29 @@ private void toggleExtraPanel() {
     }
 
     private void attemptAttach() {
+        if (mUploadPermissions.needRequesting()) {
+            mUploadPermissions.requestPermissions(this, RC_ATTEMPT_ATTACH);
+            return;
+        }
+
+        attemptAttachStep2();
+    }
+
+    private void attemptAttachStep2() {
         Intent chooserIntent = ChooserIntent.create(getContext(), R.string.pick_file_to_attach, "*/*");
         startActivityForResult(chooserIntent, RC_PICK_FILE);
     }
 
     private void attemptCamera() {
+        if (mUploadPermissions.needRequesting()) {
+            mUploadPermissions.requestPermissions(this, RC_ATTEMPT_CAMERA);
+            return;
+        }
+
+        attemptCameraStep2();
+    }
+
+    private void attemptCameraStep2() {
         Intent[] cameraIntents = ChooserIntent.buildCameraIntents(getContext());
         if (cameraIntents.length == 0) {
             // TODO: device without camera?