在Android应用程序的webview中加载URL时启动屏幕

Question

我有一个应用程序,它有2个活动,第一个启动第二个将URL加载到webview中.

它工作正常,但是当网址加载时,webview显示为空...然后我想制作一个启动画面或类似的东西,在网址加载时显示它,我在新的活动中做了,但我不知道当网址被加载时,我不知道如何关闭第三个活动...请有人帮助我吗？

这是我的代码......谢谢!

public class Visor extends  Activity {

    WebView mWebView;
    int Result;

    @Override
    public void onCreate (Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        setContentView(R.layout.visor);
        Bundle extras=getIntent().getExtras();
        String s= extras.getString("url");

        mWebView = (WebView) findViewById(R.id.webview);
        mWebView.getSettings().setJavaScriptEnabled(true);
        mWebView.getSettings().setPluginsEnabled(true);
        mWebView.getSettings().setAllowFileAccess(true);

        mWebView.loadUrl(s);
        mWebView.setWebViewClient(new VisorClient());
        mWebView.getSettings().setBuiltInZoomControls(true);

        }

    private class VisorClient extends WebViewClient {

            @Override
            public void onPageStarted(WebView view, String url, Bitmap favicon) {
                lanzarIntro();
            }
            @Override
            public void onPageFinished(WebView view, String url) {
                mWebView.loadUrl(url);
            }
     }

    public void lanzarIntro(){
        Intent i=new Intent (this, Intro.class);

        startActivity(i);


    }



}

Answer 1

我这样做是通过最初显示一个ImageView,然后一旦加载了WebView,就像这样交换它们的可见性

        WebView wv = (WebView) findViewById(R.id.webView1);
        wv.getSettings().setJavaScriptEnabled(true);
        wv.setWebViewClient(new WebViewClient() {

            ...

            @Override
            public void onPageFinished(WebView view, String url) {
                //hide loading image
                findViewById(R.id.imageLoading1).setVisibility(View.GONE);
                //show webview
                findViewById(R.id.webView1).setVisibility(View.VISIBLE);
            }


        });     
        wv.loadUrl("http://yoururlhere.com");

我的xml布局看起来像这样

    <ImageView android:id="@+id/imageLoading1"
        android:layout_height="fill_parent"
        android:layout_width="fill_parent"
        android:visibility="visible"
        android:src="@drawable/vert_loading"
        />
    <WebView android:id="@+id/webView1"
        android:layout_height="fill_parent"
        android:layout_width="fill_parent"
        android:visibility="gone"
        />

Answer 2

我有一项活动.1个xml文件和1个java类.在xml文件里面我有:

1. 的WebView
2. ImageView,我的应用程序的标志,
3. ProgressBar和
4. TextView,应用版本.

main.xml代码:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:a="http://schemas.android.com/apk/res/android"
    a:layout_width="fill_parent"
    a:layout_height="fill_parent"
    a:background="#aaaaaa"
    a:orientation="vertical" >

<WebView
    a:id="@+id/webView1"
    a:layout_width="fill_parent"
    a:layout_height="fill_parent" />

<ImageView
    a:id="@+id/imageView1"
    a:layout_width="wrap_content"
    a:layout_height="wrap_content"
    a:layout_alignParentTop="true"
    a:layout_centerHorizontal="true"
    a:layout_marginTop="46dp"
    a:src="@drawable/logo" />

<ProgressBar
    a:id="@+id/progressBar1"
    a:layout_width="wrap_content"
    a:layout_height="wrap_content"
    a:layout_below="@+id/imageView1"
    a:layout_centerHorizontal="true" />

<TextView
    a:id="@+id/textView1"
    a:layout_width="wrap_content"
    a:layout_height="wrap_content"
    a:layout_alignParentBottom="true"
    a:layout_alignParentRight="true"
    a:layout_marginBottom="13dp"
    a:layout_marginRight="13dp"
    a:text="version 1.0"
    a:textAppearance="?android:attr/textAppearanceSmall"
    a:textColor="#444444" />

</RelativeLayout>

NovcanikActivity.java代码:

package zm.Nocanik;

import android.app.Activity;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.view.View;
import android.webkit.DownloadListener;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ImageView;
import android.widget.ProgressBar;
import android.widget.TextView;


public class NovcanikActivity extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

    WebView webview = (WebView) findViewById(R.id.webView1);

    WebSettings websettings = webview.getSettings();

    websettings.setJavaScriptEnabled(true);
    websettings.setSaveFormData(false);
    websettings.setSavePassword(false);

    webview.loadUrl("http://m.novcanik.net/?appvers=1.0");
    webview.setHorizontalScrollBarEnabled(false);
    webview.setScrollBarStyle(View.SCROLLBARS_OUTSIDE_OVERLAY);
    webview.setBackgroundColor(128);

    webview.setWebViewClient(new NovcanikWebViewClient());

    webview.setDownloadListener(new DownloadListener() {
        public void onDownloadStart(String url, String userAgent,
                String contentDisposition, String mimetype,
                long contentLength) {
            Intent intent = new Intent(Intent.ACTION_VIEW);
            intent.setData(Uri.parse(url));
            startActivity(intent);

        }
    });




}

public void visible(){

    WebView webview = (WebView) findViewById(R.id.webView1);

    ImageView logo = (ImageView) findViewById(R.id.imageView1);

    ProgressBar bar = (ProgressBar) findViewById(R.id.progressBar1);

    TextView version = (TextView) findViewById(R.id.textView1);

    webview.setVisibility(10);

    logo.setVisibility(0);

    bar.setVisibility(0);

    version.setVisibility(0);

}

public void unvisible(){

    WebView webview = (WebView) findViewById(R.id.webView1);

    ImageView logo = (ImageView) findViewById(R.id.imageView1);

    ProgressBar bar = (ProgressBar) findViewById(R.id.progressBar1);

    TextView version = (TextView) findViewById(R.id.textView1);

    webview.setVisibility(0);

    logo.setVisibility(10);

    bar.setVisibility(10);

    version.setVisibility(10);

}


private class NovcanikWebViewClient extends WebViewClient {
    @Override
    public boolean shouldOverrideUrlLoading(WebView webview, String url){
        webview.loadUrl(url);
        return true;
    }

@Override
public void onReceivedError(WebView view, int errorCode,
        String description, String failingUrl) {
    // TODO Auto-generated method stub
    view.loadUrl("file:///android_asset/noconnection.html");
}

@Override
public void onPageStarted(WebView view, String url, Bitmap favicon) {

    visible();

}

@Override
public void onPageFinished(WebView view, String url) {

    unvisible();

}

}

}

对不起,没有说明.如果需要描述,我将详细描述整个代码.