<h2 dir="auto">Steps to Reproduce</h2>
<p dir="auto">I am learning how to create mobile apps at the moment. I cannot give an in-depth bug report. I am reporting a bug because similar code does not render.</p>
<p dir="auto">In lib/views/main.dart, setting the TabBarView seems to fail in one application but succeed in another. Of course, I can manually create a widget list and not use a switch and map statements. I wonder if this code is worthy of a bug report.</p>
<p dir="auto">working build</p>
<p dir="auto"><a href="https://github.com/hungrymonkey/pregnant_watermelon/tree/567712d47f31e26b53eb6ebc203f73324e404248">https://github.com/hungrymonkey/pregnant_watermelon/tree/567712d47f31e26b53eb6ebc203f73324e404248</a></p>
<p dir="auto"><a href="https://github.com/hungrymonkey/pregnant_watermelon/blob/567712d47f31e26b53eb6ebc203f73324e404248/lib/main.dart">https://github.com/hungrymonkey/pregnant_watermelon/blob/567712d47f31e26b53eb6ebc203f73324e404248/lib/main.dart</a></p>
<p dir="auto">failed build</p>
<p dir="auto"><a href="https://github.com/hungrymonkey/weather_app/blob/df30be259af667ffd06546eb73795031a5b7a881/lib/main.dart">https://github.com/hungrymonkey/weather_app/blob/df30be259af667ffd06546eb73795031a5b7a881/lib/main.dart</a></p>
<p dir="auto"><a href="https://github.com/hungrymonkey/weather_app/tree/df30be259af667ffd06546eb73795031a5b7a881">https://github.com/hungrymonkey/weather_app/tree/df30be259af667ffd06546eb73795031a5b7a881</a></p>
<p dir="auto">Step to repoduce</p>
<ol dir="auto">
<li>download weather_app project</li>
<li>Build it</li>
<li>Run it</li>
<li>TabBarView fails and leave a blank page</li>
<li>Error is thrown</li>
</ol>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="I/flutter (31980): ══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY ╞═════════════════════════════════════════════════════════
I/flutter (31980): The following assertion was thrown during performLayout():
I/flutter (31980): 'package:flutter/src/widgets/sliver.dart': Failed assertion: line 215: 'child != null': is not true.
I/flutter (31980): 
I/flutter (31980): Either the assertion indicates an error in the framework itself, or we should provide substantially
I/flutter (31980): more information in this error message to help you determine and fix the underlying cause.
I/flutter (31980): In either case, please report this assertion by filing a bug on GitHub:
I/flutter (31980):   https://github.com/flutter/flutter/issues/new"><pre class="notranslate"><code class="notranslate">I/flutter (31980): ══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY ╞═════════════════════════════════════════════════════════
I/flutter (31980): The following assertion was thrown during performLayout():
I/flutter (31980): 'package:flutter/src/widgets/sliver.dart': Failed assertion: line 215: 'child != null': is not true.
I/flutter (31980): 
I/flutter (31980): Either the assertion indicates an error in the framework itself, or we should provide substantially
I/flutter (31980): more information in this error message to help you determine and fix the underlying cause.
I/flutter (31980): In either case, please report this assertion by filing a bug on GitHub:
I/flutter (31980):   https://github.com/flutter/flutter/issues/new
</code></pre></div>
<p dir="auto">Expected Results<br>
Reproduce the same steps with pregnant watermelon commit 7fbb55828d3b0986fcee559bde351a119803bf1b</p>
<p dir="auto">The TabBarView renders properly.</p>
<p dir="auto">I am wondering what am I doing differently between pregnant_watermelon and  weather_app. The code is almost the same but one fails and the other succeeds. The pages does not matter because I change the page in pregnant_watermelon to the same all MyHomePage and it succeeded.</p>
<p dir="auto">Either throw warning sign in pregnant_watermelon or throw a better error in my_weather app to figure out what is going on.</p>
<h2 dir="auto">Logs</h2>
<p dir="auto">Run your application with <code class="notranslate">flutter run</code> and attach all the log output.</p>
<p dir="auto">Run <code class="notranslate">flutter analyze</code> and attach any output of that command also.</p>
<p dir="auto"><a href="https://github.com/flutter/flutter/files/1156094/flutter_run_log.txt">flutter_run_log.txt</a></p>
<p dir="auto"><a href="https://github.com/flutter/flutter/files/1156100/analyze_log.txt">analyze_log.txt</a></p>
<h2 dir="auto">Flutter Doctor</h2>
<p dir="auto">Paste the output of running <code class="notranslate">flutter doctor</code> here.</p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content=" [✓] Flutter (on Linux, locale en_US.UTF-8, channel alpha)
    • Flutter at /home/rice/flutter
    • Framework revision d36e2f6191 (4 weeks ago), 2017-06-21 15:09:10 -0700
    • Engine revision b0dee695ec
    • Tools Dart version 1.24.0-dev.6.7

[✓] Android toolchain - develop for Android devices (Android SDK 26.0.0)
    • Android SDK at /home/rice/Android/Sdk
    • Platform android-26, build-tools 26.0.0
    • Java binary at: /opt/android-studio/jre/bin/java
    • Java version OpenJDK Runtime Environment (build 1.8.0_112-release-b06)

[✓] Android Studio (version 2.3)
    • Android Studio at /opt/android-studio
    • Gradle version 3.2
    • Java version OpenJDK Runtime Environment (build 1.8.0_112-release-b06)

[✓] IntelliJ IDEA Community Edition (version 2017.1)
    • Flutter plugin version 15.1
    • Dart plugin version 171.4694.29

[✓] Connected devices
    • SM G900P • 8e90eeee • android-arm • Android 7.1.2 (API 25)"><pre class="notranslate"><code class="notranslate"> [✓] Flutter (on Linux, locale en_US.UTF-8, channel alpha)
    • Flutter at /home/rice/flutter
    • Framework revision d36e2f6191 (4 weeks ago), 2017-06-21 15:09:10 -0700
    • Engine revision b0dee695ec
    • Tools Dart version 1.24.0-dev.6.7

[✓] Android toolchain - develop for Android devices (Android SDK 26.0.0)
    • Android SDK at /home/rice/Android/Sdk
    • Platform android-26, build-tools 26.0.0
    • Java binary at: /opt/android-studio/jre/bin/java
    • Java version OpenJDK Runtime Environment (build 1.8.0_112-release-b06)

[✓] Android Studio (version 2.3)
    • Android Studio at /opt/android-studio
    • Gradle version 3.2
    • Java version OpenJDK Runtime Environment (build 1.8.0_112-release-b06)

[✓] IntelliJ IDEA Community Edition (version 2017.1)
    • Flutter plugin version 15.1
    • Dart plugin version 171.4694.29

[✓] Connected devices
    • SM G900P • 8e90eeee • android-arm • Android 7.1.2 (API 25)
</code></pre></div>
<blockquote>
<p dir="auto">For more information about diagnosing and reporting Flutter bugs, please see <a href="https://flutter.io/bug-reports/" rel="nofollow">https://flutter.io/bug-reports/</a>.</p>
</blockquote>
<p dir="auto">Can't seem to get a project working with both plugins on iOS and Android.  If I remove one or the other I can build and run the project.</p>
<h2 dir="auto">Steps to Reproduce</h2>
<p dir="auto">add <code class="notranslate">firebase_database: "^0.1.0"</code> to <code class="notranslate">pubspec.yaml</code><br>
add <code class="notranslate">firebase_firestore: "^0.0.1+1"</code> to <code class="notranslate">pubspec.yaml</code><br>
try to build/run to a device.  haven't tried simulators/emulators but I assume it would be the same issue.</p>
<h2 dir="auto">Logs</h2>
<p dir="auto">on iOS i see</p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="duplicate symbol _getQuery in:
        /Users/KG/Developer/Posse/flutterfirestore/flutterfirestore/build/ios/Release-iphoneos/firebase_database/libfirebase_database.a(FirebaseDatabasePlugin.o)
        /Users/KG/Developer/Posse/flutterfirestore/flutterfirestore/build/ios/Release-iphoneos/firebase_firestore/libfirebase_firestore.a(FirestorePlugin.o)
    ld: 1 duplicate symbol for architecture arm64
    clang: error: linker command failed with exit code 1 (use -v to see invocation)"><pre class="notranslate"><code class="notranslate">duplicate symbol _getQuery in:
        /Users/KG/Developer/Posse/flutterfirestore/flutterfirestore/build/ios/Release-iphoneos/firebase_database/libfirebase_database.a(FirebaseDatabasePlugin.o)
        /Users/KG/Developer/Posse/flutterfirestore/flutterfirestore/build/ios/Release-iphoneos/firebase_firestore/libfirebase_firestore.a(FirestorePlugin.o)
    ld: 1 duplicate symbol for architecture arm64
    clang: error: linker command failed with exit code 1 (use -v to see invocation)
</code></pre></div>
<p dir="auto">on Android<br>
<code class="notranslate">&gt; com.android.build.api.transform.TransformException: com.android.ide.common.process.ProcessException: java.util.concurrent.ExecutionException: com.android.dex.DexException: Multiple dex files define Lcom/google/android/gms/internal/zzbco;</code></p>
<h2 dir="auto">Flutter Doctor</h2>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="[✓] Flutter (on Mac OS X 10.12.6 16G29, locale en-US, channel master)
    • Flutter at /Users/KG/Developer/Flutter/flutter
    • Framework revision dc41544793 (29 hours ago), 2017-10-10 12:04:29 -0400
    • Engine revision 459f722b86
    • Tools Dart version 1.25.0-dev.11.0

[✓] Android toolchain - develop for Android devices (Android SDK 26.0.2)
    • Android SDK at /Users/KG/Library/Android/sdk
    • Platform android-26, build-tools 26.0.2
    • ANDROID_HOME = /Users/KG/Library/Android/sdk
    • Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 1.8.0_112-release-b06)

[✓] iOS toolchain - develop for iOS devices (Xcode 9.0)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Xcode 9.0, Build version 9A235
    • ios-deploy 1.9.2
    • CocoaPods version 1.2.1

[✓] Android Studio
    • Android Studio at /Applications/Android Studio 3.0 Preview.app/Contents
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-915-b01)

[✓] Android Studio (version 2.3)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Java version OpenJDK Runtime Environment (build 1.8.0_112-release-b06)

[✓] IntelliJ IDEA Community Edition (version 2017.2.5)
    • Flutter plugin version 18.1
    • Dart plugin version 172.4155.35"><pre class="notranslate"><code class="notranslate">[✓] Flutter (on Mac OS X 10.12.6 16G29, locale en-US, channel master)
    • Flutter at /Users/KG/Developer/Flutter/flutter
    • Framework revision dc41544793 (29 hours ago), 2017-10-10 12:04:29 -0400
    • Engine revision 459f722b86
    • Tools Dart version 1.25.0-dev.11.0

[✓] Android toolchain - develop for Android devices (Android SDK 26.0.2)
    • Android SDK at /Users/KG/Library/Android/sdk
    • Platform android-26, build-tools 26.0.2
    • ANDROID_HOME = /Users/KG/Library/Android/sdk
    • Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 1.8.0_112-release-b06)

[✓] iOS toolchain - develop for iOS devices (Xcode 9.0)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Xcode 9.0, Build version 9A235
    • ios-deploy 1.9.2
    • CocoaPods version 1.2.1

[✓] Android Studio
    • Android Studio at /Applications/Android Studio 3.0 Preview.app/Contents
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-915-b01)

[✓] Android Studio (version 2.3)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Java version OpenJDK Runtime Environment (build 1.8.0_112-release-b06)

[✓] IntelliJ IDEA Community Edition (version 2017.2.5)
    • Flutter plugin version 18.1
    • Dart plugin version 172.4155.35
</code></pre></div>