我的应用程序完全正常，直到我添加了一项检查互联网连接可用性的新功能，并在互联网不可用时显示警告对话框。当我在没有检查互联网的情况下在模拟器中运行我的代码时，它运行正常，但是当我使用与我在下面提供的相同代码验证internet connection时它向我显示了一个带有OK按钮的force close对话框我尝试了所有不同的互联网上提供的解决方案但对我没有任何作用我是Android开发的新手，虽然不知道，但根据我的研究，我肯定在我的代码中遗漏了一些内容，但不幸的是我无法弄明白。
这是我的主要活动
package com.testapp.mytestapp;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.graphics.Bitmap;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.net.Uri;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.webkit.WebChromeClient;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.FrameLayout;
import java.io.File;
import static com.testapp.mytestapp.R.*;
public class MyActivity extends Activity {
private WebView webView;
private FrameLayout customViewContainer;
private WebChromeClient.CustomViewCallback customViewCallback;
private View mCustomView;
private myWebChromeClient mWebChromeClient;
private myWebViewClient mWebViewClient;
/**
* Called when the activity is first created.
*/
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ConnectivityManager conMgr = (ConnectivityManager) getApplicationContext().getSystemService(this.CONNECTIVITY_SERVICE);
NetworkInfo netInfo = conMgr.getActiveNetworkInfo();
if (netInfo == null || !netInfo.isConnected() || !netInfo.isAvailable()) {
AlertDialog alertDialog;
alertDialog = new AlertDialog.Builder(this, style.AlertDialogCustom).create();
alertDialog.setTitle("Communication Error");
alertDialog.setMessage("Please make sure that internet connection is active.");
alertDialog.setButton("OK", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
finish();
}
});
alertDialog.show();
} else {
setContentView(R.layout.main);
AppRater appRater = new AppRater(this);
appRater.setDaysBeforePrompt(1);
appRater.setLaunchesBeforePrompt(3);
appRater.setPhrases("Rate This App",
"If you like our App don't forget to rate our application on Google Play. Thanks for your support!",
"Rate Now", "Later", "Ignore");
appRater.setTargetUri("https://play.google.com/store/apps/details?id=" + getApplicationContext().getPackageName());
appRater.show();
customViewContainer = (FrameLayout) findViewById(R.id.customViewContainer);
webView = (WebView) findViewById(R.id.webView);
mWebViewClient = new myWebViewClient();
webView.setWebViewClient(mWebViewClient);
mWebChromeClient = new myWebChromeClient();
webView.setWebChromeClient(mWebChromeClient);
webView.getSettings().setJavaScriptEnabled(true);
webView.getSettings().setAppCacheEnabled(true);
webView.getSettings().setSaveFormData(true);
webView.loadUrl("https://custom-domain-name.com/test-page.html");
}
}
public boolean inCustomView() {
return (mCustomView != null);
}
public void hideCustomView() {
mWebChromeClient.onHideCustomView();
}
@Override
protected void onPause() {
super.onPause(); //To change body of overridden methods use File | Settings | File Templates.
webView.onPause();
}
@Override
protected void onResume() {
super.onResume(); //To change body of overridden methods use File | Settings | File Templates.
webView.onResume();
}
@Override
protected void onStop() {
super.onStop(); //To change body of overridden methods use File | Settings | File Templates.
if (inCustomView()) {
hideCustomView();
}
}
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK) {
if (inCustomView()) {
hideCustomView();
return true;
}
if ((mCustomView == null) && webView.canGoBack()) {
webView.goBack();
return true;
}
}
return super.onKeyDown(keyCode, event);
}
class myWebChromeClient extends WebChromeClient {
private Bitmap mDefaultVideoPoster;
private View mVideoProgressView;
@Override
public void onShowCustomView(View view, int requestedOrientation, CustomViewCallback callback) {
onShowCustomView(view, callback); //To change body of overridden methods use File | Settings | File Templates.
}
@Override
public void onShowCustomView(View view,CustomViewCallback callback) {
// if a view already exists then immediately terminate the new one
if (mCustomView != null) {
callback.onCustomViewHidden();
return;
}
mCustomView = view;
webView.setVisibility(View.GONE);
customViewContainer.setVisibility(View.VISIBLE);
customViewContainer.addView(view);
customViewCallback = callback;
}
@Override
public View getVideoLoadingProgressView() {
if (mVideoProgressView == null) {
LayoutInflater inflater = LayoutInflater.from(MyActivity.this);
mVideoProgressView = inflater.inflate(R.layout.video_progress, null);
}
return mVideoProgressView;
}
@Override
public void onHideCustomView() {
super.onHideCustomView(); //To change body of overridden methods use File | Settings | File Templates.
if (mCustomView == null)
return;
webView.setVisibility(View.VISIBLE);
customViewContainer.setVisibility(View.GONE);
// Hide the custom view.
mCustomView.setVisibility(View.GONE);
// Remove the custom view from its container.
customViewContainer.removeView(mCustomView);
customViewCallback.onCustomViewHidden();
mCustomView = null;
}
}
class myWebViewClient extends WebViewClient {
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
if(Uri.parse(url).getHost().endsWith("custom-domain-name.com")) {
return false;
}
Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
view.getContext().startActivity(intent);
return true;
//return super.shouldOverrideUrlLoading(view, url); //To change body of overridden methods use File | Settings | File Templates.
}
}
@Override
protected void onDestroy() {
super.onDestroy();
try {
trimCache(); //if trimCache is static
} catch (Exception e) {
e.printStackTrace();
}
}
public void trimCache() {
try {
File dir = getCacheDir();
if (dir != null && dir.isDirectory()) {
deleteDir(dir);
}
} catch (Exception e) {
// TODO: handle exception
}
}
public static boolean deleteDir(File dir) {
if (dir != null && dir.isDirectory()) {
String[] children = dir.list();
for (int i = 0; i < children.length; i++) {
boolean success = deleteDir(new File(dir, children[i]));
if (!success) {
return false;
}
}
return dir.delete();
}
return false;
}
}
这是我的 AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.testapp.mytestapp" >
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.CLEAR_APP_CACHE"/>
<application android:label="@string/app_name" android:icon="@drawable/ic_launcher"
android:hardwareAccelerated="true">
<activity android:name=".MyActivity"
android:configChanges="orientation|keyboardHidden"
android:hardwareAccelerated="true"
android:label="@string/app_name"
android:theme="@android:style/Theme.NoTitleBar.Fullscreen">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
</application>
</manifest>
这是我的布局＆＃strong> main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<WebView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="@+id/webView"
android:layout_gravity="center"
/>
<FrameLayout
android:id="@+id/customViewContainer"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:visibility="gone"
/>
</LinearLayout>
以下是我的布局 video_progress.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/progress_indicator"
android:orientation="vertical"
android:layout_centerInParent="true"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ProgressBar android:id="@android:id/progress"
style="?android:attr/progressBarStyleLarge"
android:layout_gravity="center"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
<TextView android:paddingTop="5dip"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="loading"
android:textSize="14sp"
android:textColor="?android:attr/textColorPrimary"/>
</LinearLayout>
这是我的 styles.xml
<resources>
<!-- Base application theme. -->
<color name="basic_blue1">#ffffff</color>
<color name="basic_blue2">#ffffff</color>
<color name="basic_blue3">#9954BB</color>
<color name="basic_orange1">#2780E3</color>
<color name="basic_orange2">#2780E3</color>
<color name="basic_white1">#eeffffff</color>
<color name="basic_white2">#99ffffff</color>
<style name="AlertDialogCustom" parent="@android:style/Theme.Holo">
<item name="android:layout_gravity">center</item>
<item name="android:textSize">22sp</item>
</style>
<style name="app_rater" parent="@android:style/Theme.Holo">
<item name="android:layout_gravity">center</item>
<item name="android:textSize">22sp</item>
</style>
</resources>
答案 0 :(得分：2)
好的崩溃是因为你需要在你的情况之前获得你的观点的参考，因为你在onResume / onPause / onStop方法中使用你的webview对象，所以当你没有互联网时webview对象为空。
在if / else：
之前移动这一行 setContentView(R.layout.main);
customViewContainer = (FrameLayout) findViewById(R.id.customViewContainer);
webView = (WebView) findViewById(R.id.webView);