启动画面不应该从布局文件加载，加载时可能仍然有一些延迟。

最好的方法是为你的SplashScreenActivity创建一个主题，并设置android:windowBackground为一个可绘制的资源。

https://www.bignerdranch.com/blog/splash-screens-the-right-way/

简而言之:

在manifest中声明你的SplashScreenActivity:

<activity
        android:name=".activities.SplashScreenActivity"
        android:theme="@style/SplashTheme"
        android:screenOrientation="portrait">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>

在SplashScreenActivity.java中:

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

    Intent intent = new Intent(this, MainActivity_.class);
    startActivity(intent);
    finish();

}

接下来创建主题背景窗口的资源:

<style name="SplashTheme" parent="Theme.Bumpfie.Base">
    <item name="android:windowBackground">@drawable/splash</item>
</style>

可绘制文件splash.xml:

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:drawable="@android:color/white"/>
    <item>
        <bitmap
            android:gravity="center"
            android:src="@drawable/app_logo"/>
    </item>
</layer-list>

一种方法是通过创建FullScreenActivity/EmptyActivity(例如SplashScreenActivity)，并将其设置为打开应用程序时显示的第一个活动。在AndroidManifest.xml中添加以下内容到您的活动

 <intent-filter>
        <action android:name="android.intent.action.MAIN" />
        <category android:name="android.intent.category.LAUNCHER" />
</intent-filter>

然后，您可以设置一个处理程序，在几秒钟后取消此活动。

new Handler().postDelayed(new Runnable() {
            @Override
            public void run() {
                Intent i= new Intent(SplashScreenActivity.this,MainActivity.class);
                startActivity(i); //start new activity 
                finish();
            }
        }, 3000); //time in milliseconds

其次，如果你不想创建一个单独的活动，你可以在MainActivity上膨胀一个布局，并将布局可见性设置为GONE，或者在几毫秒后在现有的启动画面布局上膨胀主布局。

这是完整的代码

SplashActivity.java

public class SplashActivity extends AppCompatActivity {

private final int SPLASH_DISPLAY_DURATION = 1000;

@Override
public void onCreate(Bundle bundle) {
    super.onCreate(bundle);


    new Handler().postDelayed(new Runnable(){
        @Override
        public void run() {

            Intent mainIntent = new Intent(SplashActivity.this,MainActivity.class);
            SplashActivity.this.startActivity(mainIntent);
            SplashActivity.this.finish();
        }
    }, SPLASH_DISPLAY_DURATION);
}}

在drawables中创建bg_splash.xml

<?xml version="1.0" encoding="utf-8"?><layer-list xmlns:android="http://schemas.android.com/apk/res/android">

<item
    android:drawable="@color/app_color"/>

<item>
    <bitmap
        android:gravity="center"
        android:src="@drawable/ic_in_app_logo_big"/>
</item></layer-list>

在styles.xml中创建一个自定义主题

<style name="SplashTheme" parent="Theme.AppCompat.NoActionBar">
    <item name="android:windowBackground">@drawable/bg_splash</item>
</style>

最后在AndroidManifest.xml中指定活动的主题

<activity
        android:name=".activities.SplashActivity"
        android:label="@string/app_name"
        android:screenOrientation="portrait"
        android:theme="@style/SplashTheme">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

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

欢呼。

这里有一个简单的!

~卢诺克斯

MainActivity.java

package com.example.splashscreen;

import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
}

splashscreen.java

package com.example.splashscreen;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.os.Handler;

public class splashscreen extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.splashscreen);

        //Splash Screen duration
        int secondsDelayed = 1;
        new Handler().postDelayed(new Runnable() {
            public void run() {
                startActivity(new Intent(splashscreen.this, MainActivity.class));
                finish();
            }
        }, secondsDelayed * 3000);
    }
}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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:context=".MainActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</androidx.constraintlayout.widget.ConstraintLayout>

splashscreen.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/splashlogo"

    />

splashlogo.png

splashlogo.png

GitHub

SplashScreen

上面的答案很好，但我想补充一些其他的东西。我是Android的新手，我在开发过程中遇到了这些问题。希望这能帮助到像我这样的人。

The Splash screen is the entry point of my app, so add the following lines in AndroidManifest.xml. <activity android:name=".SplashActivity" android:theme="@android:style/Theme.DeviceDefault.Light.NoActionBar"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> The splash screen should only show once in the app life cycle, I use a boolean variable to record the state of the splash screen, and only show it on the first time. public class SplashActivity extends Activity { private static boolean splashLoaded = false; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); if (!splashLoaded) { setContentView(R.layout.activity_splash); int secondsDelayed = 1; new Handler().postDelayed(new Runnable() { public void run() { startActivity(new Intent(SplashActivity.this, MainActivity.class)); finish(); } }, secondsDelayed * 500); splashLoaded = true; } else { Intent goToMainActivity = new Intent(SplashActivity.this, MainActivity.class); goToMainActivity.setFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT); startActivity(goToMainActivity); finish(); } } }

编码快乐!

启动画面示例:

public class MainActivity extends Activity {
    private ImageView splashImageView;
    boolean splashloading = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        splashImageView = new ImageView(this);
        splashImageView.setScaleType(ScaleType.FIT_XY);
        splashImageView.setImageResource(R.drawable.ic_launcher);
        setContentView(splashImageView);
        splashloading = true;
        Handler h = new Handler();
        h.postDelayed(new Runnable() {
            public void run() {
                splashloading = false;
                setContentView(R.layout.activity_main);
            }

        }, 3000);

    }

}