当我尝试构建我的android项目时，出现此错误

错误：（8，37）错误：包android.support.design.widget不存在错误：（18，9）错误：找不到符号类TabLayout错误：（18，32）错误：找不到符号类TabLayout错误：
（21，33）错误：找不到符号变量TabLayout错误：（27，56）错误：软件包TabLayout不存在错误：（48，36）错误：找不到符号变量菜单错误：（28，57）错误：软件包TabLayout不存在错误：任务’：app：compileDebugJavaWithJavac’的执行失败。

编译失败；有关详细信息，请参见编译器错误输出。错误：（55，23）错误：找不到符号变量action_settings

这是我的代码

package com.chaos.creativo;

import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.support.design.widget.TabLayout;

/**
 * Created by ahmed on 3/7/2016.
 */
public class Signin_up extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.signing_up);
        TabLayout tabLayout = (TabLayout) findViewById(R.id.tab_layout);
        tabLayout.addTab(tabLayout.newTab().setText("SIGN IN"));
        tabLayout.addTab(tabLayout.newTab().setText("SIGN UP"));
        tabLayout.setTabGravity(TabLayout.GRAVITY_FILL);

        final ViewPager viewPager = (ViewPager) findViewById(R.id.pager);
        final PageAdapter adapter = new PageAdapter(getSupportFragmentManager(),tabLayout.getTabCount());

        viewPager.setAdapter(adapter);
        viewPager.addOnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener(tabLayout));
        tabLayout.setOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
            @Override
            public void onTabSelected(TabLayout.Tab tab) {
                viewPager.setCurrentItem(tab.getPosition());
            }

            @Override
            public void onTabUnselected(TabLayout.Tab tab) {

            }

            @Override
            public void onTabReselected(TabLayout.Tab tab) {

            }
        });
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.menu_main,menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }
}

我的build.gradle

> apply plugin: 'com.android.application'
> 
> android {
>     compileSdkVersion 23
>     buildToolsVersion "23.0.2"
> 
>     defaultConfig {
>         applicationId "com.chaos.creativo"
>         minSdkVersion 18
>         targetSdkVersion 23
>         versionCode 1
>         versionName "1.0"
>     }
>     buildTypes {
>         release {
>             minifyEnabled false
>             proguardFiles getDefaultProguardFile('proguard-android.txt'),'proguard-rules.pro'
>         }
>     } }
> 
> dependencies {
>     compile fileTree(dir: 'libs',include: ['*.jar'])
>     testCompile 'junit:junit:4.12'
>     compile 'com.android.support:appcompat-v7:23.1.1'
>     compile 'com.google.android.gms:play-services-ads:8.4.0'
>     compile 'com.google.android.gms:play-services-identity:8.4.0'
>     compile 'com.firebase:firebase-client-android:2.3.1'
>     compile 'com.google.android.gms:play-services-gcm:8.4.0'
>     compile 'com.android.support:support-v4:23.2'
>     compile 'com.android.support:design:23.2' }