Webview - 如何在Rotate上保留当前页面
Posted
tags:
篇首语:本文由小常识网(cha138.com)小编为大家整理,主要介绍了Webview - 如何在Rotate上保留当前页面相关的知识,希望对你有一定的参考价值。
我为我的企业开发了一个网站,我几乎完全使用php
所以Java语言(和android studio)对我来说真的很新。尽管如此我必须创建一个APK来使用该网站(为了阻止这个网站上的Android主页)
但是当我转动屏幕时,webview会显示主页而不是当前页面。
我做了一些研究,并整合了我在这里看到的:Android - Preventing WebView reload on Rotate
但这不起作用,我不明白为什么我总是回到“Google.com”
main activity.Java
package eu.test.chrome;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.webkit.WebChromeClient;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ProgressBar;
public class MainActivity extends AppCompatActivity {
WebView webView;
SwipeRefreshLayout swipe;
ProgressBar progressBar;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
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 onPageFinished(WebView view, String url) {
//Don't show ProgressBar
progressBar.setVisibility(View.GONE);
//Hide the SwipeRefreshLayout
swipe.setRefreshing(false);
}
});
}
/* I integrated what I saw here: https://stackoverflow.com/questions/12131025/android-preventing-webview-reload-on-rotate but that does not work
@Override
protected void onSaveInstanceState(Bundle outState )
{
super.onSaveInstanceState(outState);
webView.saveState(outState);
}
@Override
protected void onRestoreInstanceState(Bundle savedInstanceState)
{
super.onRestoreInstanceState(savedInstanceState);
webView.restoreState(savedInstanceState);
}*/
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();
}
}
}
activity_main.xml中
<?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=".MainActivity">
<ProgressBar
android:id="@+id/awv_progressBar"
style="?android:attr/progressBarStyleHorizontal"
android:layout_width="match_parent"
android:layout_height="26dp"
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>
表现
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="eu.test.chrome">
<uses-permission android:name="android.permission.INTERNET"/>
<application
android:hardwareAccelerated="false"
android:configChanges="orientation|screenSize"
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">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
答案
试试这个
import android.graphics.Bitmap;
import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.support.v4.widget.SwipeRefreshLayout;
import android.webkit.WebChromeClient;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ProgressBar;
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);
LoadWeb();
progressBar = (ProgressBar) findViewById(R.id.awv_progressBar);
progressBar.setMax(100);
progressBar.setProgress(1);
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("https://stackoverflow.com/questions/47885592/how-to-add-a-progress-loading-bar-in-webview/47885692#47885692");
}
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() {
swipe = (SwipeRefreshLayout) findViewById(R.id.swipe);
webView = (WebView) findViewById(R.id.webView);
webView.getSettings().setJavaScriptEnabled(true);
webView.getSettings().setAppCacheEnabled(true);
webView.loadUrl("http://dev.ncryptedprojects.com/bistrostays_v3/");
swipe.setRefreshing(true);
}
@Override
protected void onSaveInstanceState(Bundle outState )
{
super.onSaveInstanceState(outState);
webView.saveState(outState);
}
@Override
protected void onRestoreInstanceState(Bundle savedInstanceState)
{
super.onRestoreInstanceState(savedInstanceState);
webView.restoreState(savedInstanceState);
}
@Override
public void onBackPressed() {
if (webView.canGoBack()) {
webView.goBack();
} else {
finish();
}
}
}
并在您的清单文件中
<activity android:name=".MainActivity"
android:configChanges="orientation|screenSize">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
另一答案
为了在旋转前加载Url,您需要进行一些添加。
public class MainActivity extends AppCompatActivity {
WebView webView;
SwipeRefreshLayout swipe;
ProgressBar progressBar;
private final String CACHE_URL_KEY = "CACHE_URL";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
progressBar = (ProgressBar) findViewById(R.id.awv_progressBar);
swipe = (SwipeRefreshLayout) findViewById(R.id.swipe);
LoadWeb(savedInstanceState);
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 onPageFinished(WebView view, String url) {
//Don't show ProgressBar
progressBar.setVisibility(View.GONE);
//Hide the SwipeRefreshLayout
swipe.setRefreshing(false);
}
});
}
@Override
protected void onSaveInstanceState(Bundle outState )
{
outState.putString(CACHE_URL_KEY,webView.getUrl());
super.onSaveInstanceState(outState);
}
public void LoadWeb(Bundle savedInstanceState) {
webView = (WebView) findViewById(R.id.webView);
webView.getSettings().setJavaScriptEnabled(true);
webView.getSettings().setAppCacheEnabled(true);
if (savedInstanceState != null) {
String savedUrl = savedInstanceState.getString(CACHE_URL_KEY);
webView.loadUrl(savedUrl);
}else {
webView.loadUrl("https://www.google.com/");
}
swipe.setRefreshing(true);
}
@Override
public void onBackPressed() {
if (webView.canGoBack()) {
webView.goBack();
} else {
finish();
}
}
}
以下是制作的步骤:
- 您需要创建密钥以标识已保存的URL
private final String CACHE_URL_KEY = "CACHE_URL";
- 每次旋转时都需要保存URL
@Override protected void onSaveInstanceState(Bundle outState ) { outState.putString(CACHE_URL_KEY,webView.getUrl()); super.onSaveInstanceState(outState); }
- 您需要检查是否存在旋转。如果是,则savedInstanceState将不为null,因此检索Url并加载它。 Else Load Default页面
if (savedInstanceState != null) { String savedUrl = savedInstanceState.getString(CACHE_URL_KEY); webView.loadUrl(savedUrl); }else { webView.loadUrl("https://www.google.com/"); }
- 另外,将保存的状态传递给LoadWeb方法
另一答案
在Android中创建方法,如:
@JavascriptInterface
public boolean CallByMobApp(){
return true;
}
在JavaScript
中创建调用函数:
$(window).load(function () {
IsCallByMobileApp = false;
try {
IsCallByMobileApp = app.CallByMobApp();/*Is call by android app*/
} catch (e) {
IsCallByMobileApp = false;
}
}
根据此方法,您可以管理要打开的页面。
另一答案
您每次都调用LoadWeb方法。您需要检查savedInstanceState == null然后调用LoadWeb。如果savedInstanceState!= null,则不要调用LoadWeb
以上是关于Webview - 如何在Rotate上保留当前页面的主要内容,如果未能解决你的问题,请参考以下文章