[Wi-Fi DPP] Improve TalkBack information for events

Title and summary may be changed after user operations or Wi-Fi Easy connect handshake,
setAccessibilityLiveRegion could specify accessibility services to announce these changes.

In WifiDppAddDeviceFragment, I set title before summary for correct TalkBack announce sequence.

Bug: 137069941
Test: manual
Change-Id: Id032cfcb86c350feeac808f070665ac26261ceb8

res/layout/wifi_dpp_add_device_fragment.xml

@@ -35,7 +35,8 @@
             android:layout_height="wrap_content"
             android:layout_marginStart="?attr/sudMarginSides"
             android:layout_marginEnd="?attr/sudMarginSides"
-            android:textAlignment="center"/>
+            android:textAlignment="center"
+            android:accessibilityLiveRegion="polite"/>
 
         <LinearLayout
             android:layout_width="match_parent"

res/layout/wifi_dpp_choose_saved_wifi_network_fragment.xml

@@ -35,7 +35,8 @@
             android:layout_height="wrap_content"
             android:layout_marginStart="?attr/sudMarginSides"
             android:layout_marginEnd="?attr/sudMarginSides"
-            android:textAlignment="center"/>
+            android:textAlignment="center"
+            android:accessibilityLiveRegion="polite"/>
 
         <LinearLayout android:id="@+id/wifi_network_list_container"
             android:layout_width="match_parent"

res/layout/wifi_dpp_qrcode_generator_fragment.xml

@@ -35,7 +35,8 @@
             android:layout_height="wrap_content"
             android:layout_marginStart="?attr/sudMarginSides"
             android:layout_marginEnd="?attr/sudMarginSides"
-            android:textAlignment="center"/>
+            android:textAlignment="center"
+            android:accessibilityLiveRegion="polite"/>
 
         <LinearLayout
             android:layout_width="match_parent"

res/layout/wifi_dpp_qrcode_scanner_fragment.xml

@@ -35,7 +35,8 @@
             android:layout_height="wrap_content"
             android:layout_marginStart="?attr/sudMarginSides"
             android:layout_marginEnd="?attr/sudMarginSides"
-            android:textAlignment="center"/>
+            android:textAlignment="center"
+            android:accessibilityLiveRegion="polite"/>
 
         <LinearLayout
             android:layout_width="match_parent"

src/com/android/settings/wifi/dpp/WifiDppAddDeviceFragment.java

@@ -100,21 +100,24 @@ public class WifiDppAddDeviceFragment extends WifiDppQrCodeBaseFragment {
     }
 
     private void showErrorUi(int code, boolean isConfigurationChange) {
+        CharSequence summaryCharSequence;
         switch (code) {
             case EasyConnectStatusCallback.EASY_CONNECT_EVENT_FAILURE_INVALID_URI:
-                mSummary.setText(R.string.wifi_dpp_qr_code_is_not_valid_format);
+                summaryCharSequence = getText(R.string.wifi_dpp_qr_code_is_not_valid_format);
                 break;
 
             case EasyConnectStatusCallback.EASY_CONNECT_EVENT_FAILURE_AUTHENTICATION:
-                mSummary.setText(R.string.wifi_dpp_failure_authentication_or_configuration);
+                summaryCharSequence = getText(
+                        R.string.wifi_dpp_failure_authentication_or_configuration);
                 break;
 
             case EasyConnectStatusCallback.EASY_CONNECT_EVENT_FAILURE_NOT_COMPATIBLE:
-                mSummary.setText(R.string.wifi_dpp_failure_not_compatible);
+                summaryCharSequence = getText(R.string.wifi_dpp_failure_not_compatible);
                 break;
 
             case EasyConnectStatusCallback.EASY_CONNECT_EVENT_FAILURE_CONFIGURATION:
-                mSummary.setText(R.string.wifi_dpp_failure_authentication_or_configuration);
+                summaryCharSequence = getText(
+                        R.string.wifi_dpp_failure_authentication_or_configuration);
                 break;
 
             case EasyConnectStatusCallback.EASY_CONNECT_EVENT_FAILURE_BUSY:
@@ -135,15 +138,16 @@ public class WifiDppAddDeviceFragment extends WifiDppQrCodeBaseFragment {
                 return;
 
             case EasyConnectStatusCallback.EASY_CONNECT_EVENT_FAILURE_TIMEOUT:
-                mSummary.setText(R.string.wifi_dpp_failure_timeout);
+                summaryCharSequence = getText(R.string.wifi_dpp_failure_timeout);
                 break;
 
             case EasyConnectStatusCallback.EASY_CONNECT_EVENT_FAILURE_GENERIC:
-                mSummary.setText(R.string.wifi_dpp_failure_generic);
+                summaryCharSequence = getText(R.string.wifi_dpp_failure_generic);
                 break;
 
             case EasyConnectStatusCallback.EASY_CONNECT_EVENT_FAILURE_NOT_SUPPORTED:
-                mSummary.setText(getString(R.string.wifi_dpp_failure_not_supported, getSsid()));
+                summaryCharSequence = getString(
+                        R.string.wifi_dpp_failure_not_supported, getSsid());
                 break;
 
             case EasyConnectStatusCallback.EASY_CONNECT_EVENT_FAILURE_INVALID_NETWORK:
@@ -155,6 +159,7 @@ public class WifiDppAddDeviceFragment extends WifiDppQrCodeBaseFragment {
         }
 
         setHeaderTitle(R.string.wifi_dpp_could_not_add_device);
+        mSummary.setText(summaryCharSequence);
         mWifiApPictureView.setImageResource(R.drawable.wifi_dpp_error);
         mChooseDifferentNetwork.setVisibility(View.INVISIBLE);
         if (hasRetryButton(code)) {

src/com/android/settings/wifi/dpp/WifiDppQrCodeBaseFragment.java

@@ -72,6 +72,9 @@ public abstract class WifiDppQrCodeBaseFragment extends InstrumentedFragment {
                     .build();
             mGlifLayout.getMixin(FooterBarMixin.class).setPrimaryButton(mRightButton);
         }
+
+        mGlifLayout.getHeaderTextView().setAccessibilityLiveRegion(
+                View.ACCESSIBILITY_LIVE_REGION_POLITE);
     }
 
     protected void setHeaderIconImageResource(@DrawableRes int iconResId) {