Add user selectable Default Browser feature

- add Default Apps section in Apps / Advanced
- follow UX spec

This change depends on a Framework change which adds new APIs in PackageMaager
for setting and getting the default Browser App package name.

See bug #20144393

Change-Id: I2ff456eeaced9f740f4dd6fb6bccea6de6ea1308

src/com/android/settings/applications/ManageDefaultApps.java

@@ -0,0 +1,99 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings.applications;
+
+import android.annotation.Nullable;
+import android.content.Intent;
+import android.content.pm.PackageManager;
+import android.content.pm.ResolveInfo;
+import android.os.Bundle;
+import android.os.UserHandle;
+import android.preference.Preference;
+import android.text.TextUtils;
+import android.util.Log;
+import android.view.View;
+import com.android.settings.InstrumentedFragment;
+import com.android.settings.SettingsPreferenceFragment;
+
+import com.android.settings.R;
+
+public class ManageDefaultApps extends SettingsPreferenceFragment
+        implements Preference.OnPreferenceClickListener {
+
+    private static final String TAG = ManageDefaultApps.class.getSimpleName();
+
+    private static final String KEY_DEFAULT_BROWSER = "default_browser";
+
+    private DefaultBrowserPreference mDefaultBrowserPreference;
+    private PackageManager mPm;
+    private int myUserId;
+
+    @Override
+    public void onCreate(Bundle icicle) {
+        super.onCreate(icicle);
+
+        addPreferencesFromResource(R.xml.default_apps);
+
+        mPm = getPackageManager();
+        myUserId = UserHandle.myUserId();
+
+        mDefaultBrowserPreference = (DefaultBrowserPreference) findPreference(KEY_DEFAULT_BROWSER);
+        mDefaultBrowserPreference.setOnPreferenceClickListener(
+                new Preference.OnPreferenceClickListener() {
+                    @Override
+                    public boolean onPreferenceClick(Preference preference) {
+                        final CharSequence packageName = mDefaultBrowserPreference.getValue();
+                        if (TextUtils.isEmpty(packageName)) {
+                            return false;
+                        }
+                        return mPm.setDefaultBrowserPackageName(packageName.toString(), myUserId);
+                    }
+        });
+    }
+
+    @Override
+    public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
+        super.onViewCreated(view, savedInstanceState);
+
+        String packageName = getPackageManager().getDefaultBrowserPackageName(
+                UserHandle.myUserId());
+        if (!TextUtils.isEmpty(packageName)) {
+            // Check if the package is still there
+            Intent intent = new Intent();
+            intent.setPackage(packageName);
+            ResolveInfo info = mPm.resolveActivityAsUser(intent, 0, myUserId);
+            if (info != null) {
+                mDefaultBrowserPreference.setValue(packageName);
+            } else {
+                // Otherwise select the first one
+                mDefaultBrowserPreference.setValueIndex(0);
+            }
+        } else {
+            Log.d(TAG, "Cannot set empty default Browser value!");
+        }
+    }
+
+    @Override
+    protected int getMetricsCategory() {
+        return InstrumentedFragment.VIEW_CATEGORY_DEFAULT_APPS;
+    }
+
+    @Override
+    public boolean onPreferenceClick(Preference preference) {
+        return false;
+    }
+}