我正在关注(在 WebView 中构建 Web 应用程序)教程,但是我遇到了(导航网页历史记录)问题,我在我的设备上运行它并点击了一个链接,但是当我点击后退按钮时,应用程序关闭:
那是我的活动:
public class MainActivity extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
WebView myWebView = (WebView) findViewById(R.id.webView1);
myWebView.setWebViewClient(new MyWebViewClient());
myWebView.setWebViewClient(new WebViewClient());
WebSettings webSettings = myWebView.getSettings();
webSettings.setJavaScriptEnabled(true);
myWebView.loadUrl("http://www.google.com");
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
private class MyWebViewClient extends WebViewClient {
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
if (Uri.parse(url).getHost().equals("www.example.com")) {
// This is my web site, so do not override; let my WebView load the page
return false;
}
// Otherwise, the link is not for a page on my site, so launch another Activity that handles URLs
Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
startActivity(intent);
return true;
}
}
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
WebView myWebView = null;
// Check if the key event was the Back button and if there's history
if ((keyCode == KeyEvent.KEYCODE_BACK) && myWebView.canGoBack()) {
myWebView.goBack();
return true;
}
// If it wasn't the Back key or there's no web page history, bubble up to the default
// system behavior (probably exit the activity)
return super.onKeyDown(keyCode, event);
}
}