Java android studio启动屏幕后的白色屏幕

Java android studio启动屏幕后的白色屏幕,java,android,Java,Android,概述- 每次启动应用程序时,启动活动后都会出现一个白色屏幕,我尝试了许多解决方案,但都没有成功。如果有人知道解决方案,请帮助! 谢谢 清单文件- <application android:allowBackup="true" android:icon="@mipmap/ic_launcher" android:label="@string/app_name"

概述-

每次启动应用程序时,启动活动后都会出现一个白色屏幕,我尝试了许多解决方案,但都没有成功。如果有人知道解决方案,请帮助! 谢谢

清单文件-

    <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"
        android:usesCleartextTraffic="true">
        <activity android:name=".splash_activity"
            android:theme="@style/AppTheme">
            <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>
XML文件-

<resources>
    <!-- Base application theme. -->
    <style name="AppTheme" parent="Theme.AppCompat.NoActionBar">
        <!-- Customize your theme here. -->
        <item name="colorPrimary">@color/colorPrimary</item>
        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
        <item name="colorAccent">@color/colorAccent</item>
        <item name="android:windowDisablePreview">true</item>
        <item name="android:windowBackground">@null</item>
        <item name="android:windowIsTranslucent">true</item>
    </style>


</resources>
在这里输入代码-

Main activity-
package com.cnc.cncapp;

import androidx.appcompat.app.AppCompatActivity;

import android.graphics.Bitmap;
import android.os.Bundle;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;

public class MainActivity extends AppCompatActivity {
    private WebView mywebView;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mywebView=(WebView) findViewById(R.id.webview);
        mywebView.setWebViewClient(new WebViewClient());
        mywebView.loadUrl("https://www.cncrooms.in/");
        WebSettings webSettings=mywebView.getSettings();
        webSettings.setJavaScriptEnabled(true);
    }
    public class mywebClient extends WebViewClient{
        @Override
        public void onPageStarted(WebView view, String url, Bitmap favicon){
            super.onPageStarted(view,url,favicon);
        }
        @Override
        public boolean shouldOverrideUrlLoading(WebView view,String url){
            view.loadUrl(url);
            return true;
        }
    }
    @Override
    public void onBackPressed(){
        if(mywebView.canGoBack()) {
            mywebView.goBack();
        }
        else{
            super.onBackPressed();
        }
    }
}
主活动布局文件

另外,发布你的
MainActivity.java
classPost你的布局文件我已经添加了布局和主活动文件,你到底期望什么,另一个活动正在打开,但没有加载url,还是根本没有打开?白屏是停留很长时间还是几秒钟?应用程序是否挂起(提示用户等待或关闭)?您是否有互联网权限?是的,问题是白色屏幕停留时间长,是的,我有互联网permissions@Thompsonspartaalso,发布你的
MainActivity.java
classPost你的布局文件我已经添加了布局和主活动文件,你到底期望什么,另一个活动正在打开,但没有加载url,还是根本没有打开?白色屏幕是停留很长时间还是几秒钟?应用程序是否挂起(提示用户等待或关闭)?您是否有互联网权限?是的,问题是白色屏幕停留时间长,是的,我有互联网permissions@Thompsonsparta
<resources>
    <!-- Base application theme. -->
    <style name="AppTheme" parent="Theme.AppCompat.NoActionBar">
        <!-- Customize your theme here. -->
        <item name="colorPrimary">@color/colorPrimary</item>
        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
        <item name="colorAccent">@color/colorAccent</item>
        <item name="android:windowDisablePreview">true</item>
        <item name="android:windowBackground">@null</item>
        <item name="android:windowIsTranslucent">true</item>
    </style>


</resources>
    enter code here-
java file-
package com.cnc.cncapp;

import androidx.appcompat.app.AppCompatActivity;

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

public class splash_activity extends AppCompatActivity {

    private Handler mHandler;
    private  Runnable mRunnable;

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

        mRunnable = new Runnable() {
            @Override
            public void run() {
                startActivity(new Intent(getApplicationContext(),MainActivity.class));
            }
        };

        mHandler = new Handler();
        mHandler.postDelayed(mRunnable,2000);
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();

        if(mHandler!=null && mRunnable!=null){
            mHandler.removeCallbacks(mRunnable);
        }
    }
}

Main activity-
package com.cnc.cncapp;

import androidx.appcompat.app.AppCompatActivity;

import android.graphics.Bitmap;
import android.os.Bundle;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;

public class MainActivity extends AppCompatActivity {
    private WebView mywebView;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mywebView=(WebView) findViewById(R.id.webview);
        mywebView.setWebViewClient(new WebViewClient());
        mywebView.loadUrl("https://www.cncrooms.in/");
        WebSettings webSettings=mywebView.getSettings();
        webSettings.setJavaScriptEnabled(true);
    }
    public class mywebClient extends WebViewClient{
        @Override
        public void onPageStarted(WebView view, String url, Bitmap favicon){
            super.onPageStarted(view,url,favicon);
        }
        @Override
        public boolean shouldOverrideUrlLoading(WebView view,String url){
            view.loadUrl(url);
            return true;
        }
    }
    @Override
    public void onBackPressed(){
        if(mywebView.canGoBack()) {
            mywebView.goBack();
        }
        else{
            super.onBackPressed();
        }
    }
}
enter code here-
layout file-
<?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"
    android:background="#000000"
    tools:context=".splash_activity">

    <ImageView
        android:layout_width="228dp"
        android:layout_height="209dp"
        android:layout_marginStart="91dp"
        android:layout_marginLeft="91dp"
        android:layout_marginTop="261dp"
        android:layout_marginEnd="92dp"
        android:layout_marginRight="92dp"
        android:layout_marginBottom="261dp"
        android:src="@drawable/rsz_sitelogo"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent">

    </ImageView>

</androidx.constraintlayout.widget.ConstraintLayout>
enter code here
Main Activity layout file
<?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:context=".MainActivity">


    <WebView
        android:id="@+id/webview"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />
</RelativeLayout>