Android 如何在第一次启动屏幕之前实现介绍滑块？

清单文件

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="demo.com.xapp">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".IntroActivity"></activity>
        <activity android:name=".SplashActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity android:name=".MainActivity"></activity>
    </application>

</manifest>

启动屏幕活动-

public class SplashActivity extends AppCompatActivity {

        public void onAttachedToWindow() {
            super.onAttachedToWindow();
            Window window = getWindow();
            window.setFormat(PixelFormat.RGBA_8888);
        }
        /** Called when the activity is first created. */
        Thread splashTread;
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_splash);
            StartAnimations();
        }
        private void StartAnimations() {
            Animation anim = AnimationUtils.loadAnimation(this, R.anim.alpha);
            anim.reset();
            LinearLayout l=(LinearLayout) findViewById(R.id.lin_lay);
            l.clearAnimation();
            l.startAnimation(anim);

            anim = AnimationUtils.loadAnimation(this, R.anim.translate);
            anim.reset();
            TextView iv = (TextView) findViewById(R.id.splash);
            iv.clearAnimation();
            iv.startAnimation(anim);

            splashTread = new Thread() {
                @Override
                public void run() {
                    try {
                        int waited = 0;
                        // Splash screen pause time
                        while (waited < 6000) {
                            sleep(100);
                            waited += 100;
                        }
                        Intent intent = new Intent(SplashActivity.this,
                                MainActivity.class);
                        intent.setFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
                        startActivity(intent);
                        SplashActivity.this.finish();
                    } catch (InterruptedException e) {
                        // do nothing
                    } finally {
                        SplashActivity.this.finish();
                    }

                }
            };
            splashTread.start();

        }

    }

公共类SplashActivity扩展了AppCompatActivity{
公共空间和附加的Towindow（）{
super.onAttachedToWindow（）；
Window=getWindow（）；
setFormat（PixelFormat.RGBA_8888）；
}
/**在首次创建活动时调用*/
线溅胎面；
@凌驾
创建时的公共void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
setContentView（R.layout.activity_splash）；
StartAnimations（）；
}
私有void StartAnimations（）{
Animation anim=AnimationUtils.loadAnimation（this，R.anim.alpha）；
动画重置（）；
LinearLayout l=（LinearLayout）findViewById（R.id.Linu lay）；
l、 clearAnimation（）；
l、 startAnimation（anim）；
anim=AnimationUtils.loadAnimation（this，R.anim.translate）；
动画重置（）；
TextView iv=（TextView）findViewById（R.id.splash）；
iv.清晰动画（）；
iv.启动动画（动画）；
splashTread=新线程（）{
@凌驾
公开募捐{
试一试{
int=0；
//启动屏幕暂停时间
while（等待时间<6000）{
睡眠（100）；
平均值+=100；
}
意向意向=新意向（SplashActivity.this，
主要活动（课堂）；
intent.setFlags（intent.FLAG\u活动\u无\u动画）；
星触觉（意向）；
SplashActivity.this.finish（）；
}捕捉（中断异常e）{
//无所事事
}最后{
SplashActivity.this.finish（）；
}
}
};
splashTread.start（）；
}
}

---

我们如何在第一次安装应用程序时在启动屏幕前显示简介滑块。第二次仅启动屏幕不显示简介滑块。我是android新手，请帮我解决这个问题。

您可以使用SharedReference保存一些值，每次用户将进入您的应用程序时，检查保存的SharedReference的值，看看这是否是第一次。

首先创建一个方法以返回正确的布尔值（如果这是用户的第一次或不是第一次）：

 //check if this is the user first time in the app and if it not - do not show tutorial
public static Boolean checkPref(Context context ,String prefKey){
    SharedPreferences sharedPreferences = context.getSharedPreferences("prefs",MODE_PRIVATE);
    Boolean firstStart = sharedPreferences.getBoolean(prefKey,true);
    //if this is the users first time return true
    if(firstStart){
        return  true;
    }else{
        return false;
    }
}

 if(checkPref(Context,"yourkey")){
        //the user is logged in for the first time
        callFirstTimeMethod();
    }

现在创建一种方法来更改用户首次登录应用程序时的共享参考信息

  public static void changePrefs(Context context,String key){
    //this part will change the first time loging boolean fron true to false(this will make sure that the user wont see the tutorial again )
    SharedPreferences sharedPreferences = context.getSharedPreferences("prefs",MODE_PRIVATE);
    SharedPreferences.Editor editor = sharedPreferences.edit();
    editor.putBoolean(key,false);
    editor.apply();
}

当用户进入你的应用程序时，检查这是否是他的第一次：

 //check if this is the user first time in the app and if it not - do not show tutorial
public static Boolean checkPref(Context context ,String prefKey){
    SharedPreferences sharedPreferences = context.getSharedPreferences("prefs",MODE_PRIVATE);
    Boolean firstStart = sharedPreferences.getBoolean(prefKey,true);
    //if this is the users first time return true
    if(firstStart){
        return  true;
    }else{
        return false;
    }
}

 if(checkPref(Context,"yourkey")){
        //the user is logged in for the first time
        callFirstTimeMethod();
    }

在用户第一次登录后，您需要更改您的SharedReference值，这样您就知道他不是第一次登录（以后登录时）

WelcomeActivity.java

import android.content.Context;
import android.content.Intent;
import android.graphics.Color;
import android.os.Build;
import android.os.Bundle;
import android.text.Html;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.TextView;

import androidx.appcompat.app.AppCompatActivity;
import androidx.viewpager.widget.PagerAdapter;
import androidx.viewpager.widget.ViewPager;

import com.example.pagatodo.Common.PrefManager;
import com.example.pagatodo.R;
import com.example.pagatodo.SplashScreenActivity;

public class WelcomeActivity extends AppCompatActivity {

    private ViewPager viewPager;
    private MyViewPagerAdapter myViewPagerAdapter;
    private LinearLayout dotsLayout;
    private TextView[] dots;
    private int[] layouts;
    private Button btnSkip, btnNext;
    private PrefManager prefManager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // Checking for first time launch - before calling setContentView()
        prefManager = new PrefManager(this);
        if (!prefManager.isFirstTimeLaunch()) {
            launchHomeScreen();
            finish();
        }

        // Making notification bar transparent
        if (Build.VERSION.SDK_INT >= 21) {
            getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
        }

        setContentView(R.layout.activity_welcome);

        viewPager = (ViewPager) findViewById(R.id.view_pager);
        dotsLayout = (LinearLayout) findViewById(R.id.layoutDots);
        btnSkip = (Button) findViewById(R.id.btn_skip);
        btnNext = (Button) findViewById(R.id.btn_next);

        layouts = new int[]{
                R.layout.welcome_slide1,
                R.layout.welcome_slide2,
//                R.layout.welcome_slide3,
                R.layout.welcome_slide4};

        // adding bottom dots
        addBottomDots(0);

        // making notification bar transparent
        changeStatusBarColor();

        myViewPagerAdapter = new MyViewPagerAdapter();
        viewPager.setAdapter(myViewPagerAdapter);
        viewPager.addOnPageChangeListener(viewPagerPageChangeListener);

        btnSkip.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                launchHomeScreen();
            }
        });

        btnNext.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // checking for last page
                // if last page home screen will be launched
                int current = getItem(+1);
                if (current < layouts.length) {
                    // move to next screen
                    viewPager.setCurrentItem(current);
                } else {
                    launchHomeScreen();
                }
            }
        });
    }

    private void addBottomDots(int currentPage) {
        dots = new TextView[layouts.length];

        int[] colorsActive = getResources().getIntArray(R.array.array_dot_active);
        int[] colorsInactive = getResources().getIntArray(R.array.array_dot_inactive);

        dotsLayout.removeAllViews();
        for (int i = 0; i < dots.length; i++) {
            dots[i] = new TextView(this);
            dots[i].setText(Html.fromHtml("&#8226;"));
            dots[i].setTextSize(35);
            dots[i].setTextColor(colorsInactive[currentPage]);
            dotsLayout.addView(dots[i]);
        }

        if (dots.length > 0)
            dots[currentPage].setTextColor(colorsActive[currentPage]);
    }

    private int getItem(int i) {
        return viewPager.getCurrentItem() + i;
    }

    private void launchHomeScreen() {
        prefManager.setFirstTimeLaunch(false);
        startActivity(new Intent(WelcomeActivity.this, SplashScreenActivity.class));
        finish();
    }

    //  viewpager change listener
    ViewPager.OnPageChangeListener viewPagerPageChangeListener = new ViewPager.OnPageChangeListener() {

        @Override
        public void onPageSelected(int position) {
            addBottomDots(position);

            // changing the next button text 'NEXT' / 'GOT IT'
            if (position == layouts.length - 1) {
                // last page. make button text to GOT IT
                btnNext.setText(getString(R.string.start));
                btnSkip.setVisibility(View.GONE);
            } else {
                // still pages are left
                btnNext.setText(getString(R.string.next));
                btnSkip.setVisibility(View.VISIBLE);
            }
        }

        @Override
        public void onPageScrolled(int arg0, float arg1, int arg2) {

        }

        @Override
        public void onPageScrollStateChanged(int arg0) {

        }
    };

    /**
     * Making notification bar transparent
     */
    private void changeStatusBarColor() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
            Window window = getWindow();
            window.addFlags(WindowManager.LayoutParams.FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS);
            window.setStatusBarColor(Color.TRANSPARENT);
        }
    }

    /**
     * View pager adapter
     */
    public class MyViewPagerAdapter extends PagerAdapter {
        private LayoutInflater layoutInflater;

        public MyViewPagerAdapter() {
        }

        @Override
        public Object instantiateItem(ViewGroup container, int position) {
            layoutInflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);

            View view = layoutInflater.inflate(layouts[position], container, false);
            container.addView(view);

            return view;
        }

        @Override
        public int getCount() {
            return layouts.length;
        }

        @Override
        public boolean isViewFromObject(View view, Object obj) {
            return view == obj;
        }


        @Override
        public void destroyItem(ViewGroup container, int position, Object object) {
            View view = (View) object;
            container.removeView(view);
        }
    }
}

导入android.content.Context；
导入android.content.Intent；
导入android.graphics.Color；
导入android.os.Build；
导入android.os.Bundle；
导入android.text.Html；
导入android.view.LayoutInflater；
导入android.view.view；
导入android.view.ViewGroup；
导入android.view.Window；
导入android.view.WindowManager；
导入android.widget.Button；
导入android.widget.LinearLayout；
导入android.widget.TextView；
导入androidx.appcompat.app.appcompat活动；
导入androidx.viewpager.widget.PagerAdapter；
导入androidx.viewpager.widget.viewpager；
导入com.example.pagatodo.Common.PrefManager；
导入com.example.pagatodo.R；
导入com.example.pagatodo.SplashScreenActivity；
公共类WelcomeActivity扩展了AppCompatActivity{
私人视页机视页机；
私人MyViewPagerAdapter MyViewPagerAdapter；
私人线路布局点slayout；
私有文本视图[]点；
私人int[]布局；
专用按钮btnSkip，btnNext；
私人理财经理；
@凌驾
创建时受保护的void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
//正在检查首次启动-在调用setContentView（）之前
prefManager=新的prefManager（此）；
如果（！prefManager.isFirstTimeLaunch（））{
启动主屏幕（）；
完成（）；
}
//使通知栏透明
如果（Build.VERSION.SDK_INT>=21）{
getWindow（）.getDecorView（）.SetSystemMivibility（View.SYSTEM_UI_FLAG_LAYOUT_STABLE | View.SYSTEM_UI_FLAG_LAYOUT_全屏）；
}
setContentView（R.layout.activity_welcome）；
viewPager=（viewPager）findViewById（R.id.view\u pager）；
dotsLayout=（LinearLayout）findViewById（R.id.layoutDots）；
btnSkip=（按钮）findViewById（R.id.btn\u skip）；
btnNext=（按钮）findViewById（R.id.btn_next）；
布局=新int[]{
R.layout.welcome_幻灯片1，
R.layout.welcome_幻灯片2，
//R.layout.welcome_幻灯片3，
R.layout.welcome_slide4}；
//添加底点
添加点（0）；
//使通知栏透明
changeStatusBarColor（）；
myViewPagerAdapter=新的myViewPagerAdapter（）；
设置适配器（myViewPagerAdapter）；
viewPager.addOnPageChangeListener（viewPagerPageChangeListener）；
btnSkip.setOnClickListener（新视图.OnClickListener（）{
@凌驾
公共void onClick（视图v）{
启动主屏幕（）；
}
});
btnNext.setOnClickListener（新视图.OnClickListener（）{
@凌驾
公共void onClick（视图v）{
//检查最后一页
//如果最后一页主页将启动
int current=getIt
private void callFirstTimeMethod() {
    //your code goes here for the first time

    changePrefs(Context,"yourkey");

}

import android.content.Context;
import android.content.Intent;
import android.graphics.Color;
import android.os.Build;
import android.os.Bundle;
import android.text.Html;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.TextView;

import androidx.appcompat.app.AppCompatActivity;
import androidx.viewpager.widget.PagerAdapter;
import androidx.viewpager.widget.ViewPager;

import com.example.pagatodo.Common.PrefManager;
import com.example.pagatodo.R;
import com.example.pagatodo.SplashScreenActivity;

public class WelcomeActivity extends AppCompatActivity {

    private ViewPager viewPager;
    private MyViewPagerAdapter myViewPagerAdapter;
    private LinearLayout dotsLayout;
    private TextView[] dots;
    private int[] layouts;
    private Button btnSkip, btnNext;
    private PrefManager prefManager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // Checking for first time launch - before calling setContentView()
        prefManager = new PrefManager(this);
        if (!prefManager.isFirstTimeLaunch()) {
            launchHomeScreen();
            finish();
        }

        // Making notification bar transparent
        if (Build.VERSION.SDK_INT >= 21) {
            getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
        }

        setContentView(R.layout.activity_welcome);

        viewPager = (ViewPager) findViewById(R.id.view_pager);
        dotsLayout = (LinearLayout) findViewById(R.id.layoutDots);
        btnSkip = (Button) findViewById(R.id.btn_skip);
        btnNext = (Button) findViewById(R.id.btn_next);

        layouts = new int[]{
                R.layout.welcome_slide1,
                R.layout.welcome_slide2,
//                R.layout.welcome_slide3,
                R.layout.welcome_slide4};

        // adding bottom dots
        addBottomDots(0);

        // making notification bar transparent
        changeStatusBarColor();

        myViewPagerAdapter = new MyViewPagerAdapter();
        viewPager.setAdapter(myViewPagerAdapter);
        viewPager.addOnPageChangeListener(viewPagerPageChangeListener);

        btnSkip.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                launchHomeScreen();
            }
        });

        btnNext.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // checking for last page
                // if last page home screen will be launched
                int current = getItem(+1);
                if (current < layouts.length) {
                    // move to next screen
                    viewPager.setCurrentItem(current);
                } else {
                    launchHomeScreen();
                }
            }
        });
    }

    private void addBottomDots(int currentPage) {
        dots = new TextView[layouts.length];

        int[] colorsActive = getResources().getIntArray(R.array.array_dot_active);
        int[] colorsInactive = getResources().getIntArray(R.array.array_dot_inactive);

        dotsLayout.removeAllViews();
        for (int i = 0; i < dots.length; i++) {
            dots[i] = new TextView(this);
            dots[i].setText(Html.fromHtml("&#8226;"));
            dots[i].setTextSize(35);
            dots[i].setTextColor(colorsInactive[currentPage]);
            dotsLayout.addView(dots[i]);
        }

        if (dots.length > 0)
            dots[currentPage].setTextColor(colorsActive[currentPage]);
    }

    private int getItem(int i) {
        return viewPager.getCurrentItem() + i;
    }

    private void launchHomeScreen() {
        prefManager.setFirstTimeLaunch(false);
        startActivity(new Intent(WelcomeActivity.this, SplashScreenActivity.class));
        finish();
    }

    //  viewpager change listener
    ViewPager.OnPageChangeListener viewPagerPageChangeListener = new ViewPager.OnPageChangeListener() {

        @Override
        public void onPageSelected(int position) {
            addBottomDots(position);

            // changing the next button text 'NEXT' / 'GOT IT'
            if (position == layouts.length - 1) {
                // last page. make button text to GOT IT
                btnNext.setText(getString(R.string.start));
                btnSkip.setVisibility(View.GONE);
            } else {
                // still pages are left
                btnNext.setText(getString(R.string.next));
                btnSkip.setVisibility(View.VISIBLE);
            }
        }

        @Override
        public void onPageScrolled(int arg0, float arg1, int arg2) {

        }

        @Override
        public void onPageScrollStateChanged(int arg0) {

        }
    };

    /**
     * Making notification bar transparent
     */
    private void changeStatusBarColor() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
            Window window = getWindow();
            window.addFlags(WindowManager.LayoutParams.FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS);
            window.setStatusBarColor(Color.TRANSPARENT);
        }
    }

    /**
     * View pager adapter
     */
    public class MyViewPagerAdapter extends PagerAdapter {
        private LayoutInflater layoutInflater;

        public MyViewPagerAdapter() {
        }

        @Override
        public Object instantiateItem(ViewGroup container, int position) {
            layoutInflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);

            View view = layoutInflater.inflate(layouts[position], container, false);
            container.addView(view);

            return view;
        }

        @Override
        public int getCount() {
            return layouts.length;
        }

        @Override
        public boolean isViewFromObject(View view, Object obj) {
            return view == obj;
        }


        @Override
        public void destroyItem(ViewGroup container, int position, Object object) {
            View view = (View) object;
            container.removeView(view);
        }
    }
}

    <?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:showIn="@layout/activity_welcome">


    <androidx.viewpager.widget.ViewPager
        android:id="@+id/view_pager"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <LinearLayout
        android:id="@+id/layoutDots"
        android:layout_width="match_parent"
        android:layout_height="@dimen/dots_height"
        android:layout_alignParentBottom="true"
        android:layout_marginBottom="@dimen/dots_margin_bottom"
        android:gravity="center"
        android:orientation="horizontal"></LinearLayout>

    <View
        android:layout_width="match_parent"
        android:layout_height="1dp"
        android:alpha=".5"
        android:layout_above="@id/layoutDots"
        android:background="@android:color/white" />

    <Button
        android:id="@+id/btn_next"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_alignParentRight="true"
        android:background="@null"
        android:text="@string/next"
        android:textColor="@android:color/white" />

    <Button
        android:id="@+id/btn_skip"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_alignParentLeft="true"
        android:background="@null"
        android:text="@string/skip"
        android:textColor="@android:color/white" />

</RelativeLayout>