如何正确实现Android启动屏画面的方法（避免白屏）

<?xml version="1.0" encoding="utf-8"?><layer-list xmlns:android="http://schemas.android.com/apk/res/android">  <item android:drawable="@color/colorPrimary"/>  <item android:gravity="center" android:width="100dp" android:height="100dp">    <bitmap      android:gravity="fill_horizontal|fill_vertical"      android:src="@drawable/logo"/>  </item></layer-list>

<resources>  <!-- Base application theme. -->  <style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">    <!-- Customize your theme here. -->    <item name="colorPrimary">@color/colorPrimary</item>    <item name="colorPrimaryDark">@color/colorPrimaryDark</item>    <item name="colorAccent">@color/colorAccent</item>  </style>  <style name="SplashTheme" parent="Theme.AppCompat.Light.NoActionBar">    <item name="android:windowBackground">@drawable/splash_background</item>  </style></resources>

package com.example.jtdan.goodSplash;import android.content.Intent;import android.os.Bundle;import android.support.v7.app.AppCompatActivity;public class SplashActivity extends AppCompatActivity {  @Override  protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    //switch from splash activity to main activity    Intent intent = new Intent(this, MainActivity.class);    startActivity(intent);    finish();  }}

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"  package="com.example.jtdan.goodSplash">  <application    android:allowBackup="true"    android:icon="@mipmap/ic_launcher"    android:label="goodSplash"    android:roundIcon="@mipmap/ic_launcher_round"    android:supportsRtl="true"    android:theme="@style/AppTheme">    <activity android:name="com.example.jtdan.goodSplash.SplashActivity" android:theme="@style/SplashTheme">      <intent-filter>        <action android:name="android.intent.action.MAIN" />        <category android:name="android.intent.category.LAUNCHER" />      </intent-filter>    </activity>    <activity android:name="com.example.jtdan.goodSplash.MainActivity"></activity>  </application></manifest>