fixed e2e and silence warnings

playground/e2e/app.test.js

   });
 
   it('switch to tab based app', () => {
-    elementById('btnSwitchToTabs').tap();
+    elementByLabel('Switch to tab based app').tap();
     expect(elementByLabel('This is a tab screen')).toBeVisible();
   });
 
   xit('switch to tabs with side menus', () => {
-    elementById('btnSwitchToTabsWithMenus').tap();
+    elementByLabel('Switch to tab based app with side menus').tap();
     expect(elementByLabel('This is a tab screen')).toBeVisible();
   });
 });
 function elementByLabel(label) {
   return element(by.label(label));
 }
-
-function elementById(id) {
-  return element(by.id(id));
-}

playground/scripts/ignoreReactWarnings.rb

 
 project = Xcodeproj::Project.open(__dir__ + "/../node_modules/react-native/React/React.xcodeproj")
 
-project.build_configuration_list['Release'].build_settings['WARNING_CFLAGS'] = ['-Wno-shorten-64-to-32','-Wno-unused-parameter','-Wno-unreachable-code','-Wno-deprecated-declarations','-Wno-extra-tokens','-Wno-unused-variable','-Wno-incompatible-pointer-types','-Wno-conditional-uninitialized','-Wno-undeclared-selector','-Wno-objc-protocol-property-synthesis']
+warning_flags = ['-Wno-shorten-64-to-32','-Wno-unused-parameter','-Wno-unreachable-code','-Wno-deprecated-declarations','-Wno-extra-tokens','-Wno-unused-variable','-Wno-incompatible-pointer-types','-Wno-conditional-uninitialized','-Wno-undeclared-selector','-Wno-objc-protocol-property-synthesis']
+
+project.build_configuration_list['Debug'].build_settings['WARNING_CFLAGS'] = warning_flags
+project.build_configuration_list['Release'].build_settings['WARNING_CFLAGS'] = warning_flags
 
 raise "Error: Unable to save Xcode project" unless project.save()

playground/src/containers/WelcomeScreen.js

       <View style={styles.root}>
         <Text style={styles.h1}>{`React Native Navigation!`}</Text>
         <Button
-          testId="btnSwitchToTabs"
           title="Switch to tab based app"
           onPress={this.onClickSwitchToTabs}
         />
         <Button
-          testId="btnSwitchToTabsWithMenus"
           title="Switch to tab based app with side menus"
           onPress={this.onClickSwitchToTabsWithSideMenus}
         />