examples: Android helloworld to pass Google lint (#10518)

These changes allow the Android helloworld example to pass the lint
checks of the Google internal build system.

examples/android/helloworld/app/src/main/java/io/grpc/helloworldexample/HelloworldActivity.java

@@ -50,6 +50,13 @@ protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_helloworld);
  sendButton = (Button) findViewById(R.id.send_button);
+ sendButton.setOnClickListener(
+ new View.OnClickListener() {
+ @Override
+ public void onClick(View v) {
+ sendMessage(v);
+ }
+ });
  hostEdit = (EditText) findViewById(R.id.host_edit_text);
  portEdit = (EditText) findViewById(R.id.port_edit_text);
  messageEdit = (EditText) findViewById(R.id.message_edit_text);

examples/android/helloworld/app/src/main/res/layout/activity_helloworld.xml

@@ -13,6 +13,7 @@
  android:layout_weight="2"
  android:layout_width="0dp"
  android:layout_height="wrap_content"
+ android:inputType="text"
  android:hint="Enter Host" />
  <EditText
  android:id="@+id/port_edit_text"
@@ -28,13 +29,13 @@
  android:id="@+id/message_edit_text"
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
+ android:inputType="text"
  android:hint="Enter message to send" />
 
  <Button
  android:id="@+id/send_button"
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
- android:onClick="sendMessage"
  android:text="Send Grpc Request" />
 
  <TextView