如何在 WebView 中添加进度/加载栏

Question

我为我的企业家开发了一个网站，我几乎只使用 PHP

所以 Java 语言（和 android studio）对我来说真的是新的

尽管如此，我必须创建一个 APK 才能使用该网站（为了阻止该网站上的 android home）

目前我设法设置了刷新页面，现在我正在尝试向使用 WebView 的应用程序添加进度/加载栏，但它不起作用..

主活动.java

import android.support.v4.widget.SwipeRefreshLayout;
import android.app.Activity;
import android.os.Bundle;
import android.webkit.WebView;
import android.webkit.WebViewClient;

public class MainActivity extends Activity {

    WebView webView;

    SwipeRefreshLayout swipe;

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

        swipe = (SwipeRefreshLayout) findViewById(R.id.swipe);
        swipe.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
            @Override
            public void onRefresh() {
                webView.reload();
            }
        });

        LoadWeb();

    }


    public void LoadWeb(){

        webView = (WebView) findViewById(R.id.webView);
        webView.getSettings().setJavaScriptEnabled(true);
        webView.getSettings().setAppCacheEnabled(true);
        webView.loadUrl("https://www.google.com/");
        swipe.setRefreshing(true);
        webView.setWebViewClient(new WebViewClient(){

            public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {

                webView.loadUrl("file:///android_asset/error.html");
            }

            public  void onLoadResource(WebView view, String url) { //Doesn't work
                swipe.setRefreshing(true);
            }

            public  void  onPageFinished(WebView view, String url){

                //Hide the SwipeReefreshLayout

                swipe.setRefreshing(false);
            }

        });
    }

    @Override
    public void onBackPressed(){

        if (webView.canGoBack()){
            webView.goBack();
        }else {
            finish();
        }
    }
}

Activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.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="eu.test.testappli.MainActivity">

    <android.support.v4.widget.SwipeRefreshLayout
        android:id="@+id/swipe"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

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

    </android.support.v4.widget.SwipeRefreshLayout>

</android.support.constraint.ConstraintLayout>

这可能看起来很简单，但 Java 对我来说仍然很模糊，所以我无法实现我在网上找到的代码片段..

Answer 1

试试这个我对你的代码做了一些改变

import android.support.v4.widget.SwipeRefreshLayout;
import android.webkit.WebChromeClient;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ProgressBar;
import android.support.v7.widget.Toolbar;
public class Main2Activity extends AppCompatActivity {

    WebView webView;

    SwipeRefreshLayout swipe;
    ProgressBar progressBar;
    Toolbar toolbar;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);

        progressBar = (ProgressBar) findViewById(R.id.awv_progressBar);
        swipe = (SwipeRefreshLayout) findViewById(R.id.swipe);
        LoadWeb();

        progressBar.setMax(100);
        progressBar.setProgress(1);


        swipe = (SwipeRefreshLayout) findViewById(R.id.swipe);
        swipe.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
            @Override
            public void onRefresh() {
                webView.reload();
            }
        });

        webView.setWebChromeClient(new WebChromeClient() {
            public void onProgressChanged(WebView view, int progress) {


                progressBar.setProgress(progress);
            }
        });

        webView.setWebViewClient(new WebViewClient() {


            @Override
        public void onPageStarted(WebView view, String url, Bitmap favicon) {
            super.onPageStarted(view, url, favicon);
            progressBar.setVisibility(View.VISIBLE);
        }


            public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {

                webView.loadUrl("file:///android_asset/error.html");
            }

            public void onLoadResource(WebView view, String url) { //Doesn't work
                //swipe.setRefreshing(true);
            }

            public void onPageFinished(WebView view, String url) {

                //Hide the SwipeReefreshLayout
                progressBar.setVisibility(View.GONE);
                swipe.setRefreshing(false);
            }

        });


    }

    public void LoadWeb() {

        webView = (WebView) findViewById(R.id.webView);
        webView.getSettings().setJavaScriptEnabled(true);
        webView.getSettings().setAppCacheEnabled(true);
        webView.loadUrl("https://www.google.com/");
        swipe.setRefreshing(true);
    }

    @Override
    public void onBackPressed() {

        if (webView.canGoBack()) {
            webView.goBack();
        } else {
            finish();
        }
    }

}

布局文件

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:id="@+id/rel_parent"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".Main2Activity">



    <ProgressBar
        android:id="@+id/awv_progressBar"
        style="?android:attr/progressBarStyleHorizontal"
        android:layout_width="match_parent"
        android:layout_height="15dp"
        android:layout_marginTop="7dp"
        android:indeterminate="true" />


    <android.support.v4.widget.SwipeRefreshLayout
        android:id="@+id/swipe"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

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

    </android.support.v4.widget.SwipeRefreshLayout>


</LinearLayout>

将此主题添加到您的活动中

<style name="AppTheme3" 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>

输出