我正在尝试将图像添加到活动背景，这样如果没有互联网连接，它也会显示全屏图像。我有图像，但我无法显示它。这是我的代码。
public class MainActivity extends Activity {
private WebView webView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
webView = (WebView) findViewById(R.id.webview);
ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
android.net.NetworkInfo wifi = cm
.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
android.net.NetworkInfo datac = cm
.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
if ((wifi != null & datac != null)
&& (wifi.isConnected() | datac.isConnected())) {
CookieManager cookieManager = CookieManager.getInstance();
cookieManager.setAcceptCookie(true);
webView = (WebView) findViewById(R.id.webview);
webView.getSettings().setJavaScriptEnabled(true);
webView.setWebChromeClient(new WebChromeClient() {
public void onProgressChanged(WebView view, int progress) {
MainActivity.this.setProgress(progress * 1000);
}
});
webView.setWebViewClient(new MyWebViewClient() {
public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
Toast.makeText(MainActivity.this, "An error occurred " + description, Toast.LENGTH_LONG).show();
}
});
webView.loadUrl("http://mysite.com/?ma=1");
}
else{
this -----> ImageView iv = new ImageView(this);
iv.setImageResource(R.drawable.noconnect);
iv.setAdjustViewBounds(true);
Toast toast = Toast.makeText(MainActivity.this, "No Internet Connection", Toast.LENGTH_LONG);
toast.show();
}
}
private class MyWebViewClient extends WebViewClient {
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
if (Uri.parse(url).getHost().equals("mysite.com")) {
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) {
if ((keyCode == KeyEvent.KEYCODE_BACK) && webView.canGoBack()) {
webView.goBack();
return true;
}
return super.onKeyDown(keyCode, event);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item)
{
switch (item.getItemId())
{
case R.id.logout:
finish();
return true;
}
return false;
}
}
编辑：这是 XML，这样会导致它在加载时崩溃。
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="@+id/pmlayout" >
<ImageView
android:id="@+id/noconn"
android:background="@drawable/noconnect"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:scaleType="matrix"
android:visibility="visible" >
</ImageView>
<WebView android:id="@+id/webview"
android:layout_width="fill_parent"
android:layout_height="fill_parent"/>
</LinearLayout>
编辑2：
这是我现在遇到的崩溃错误。
04-07 18:51:17.920: E/AndroidRuntime(8113): FATAL EXCEPTION: main
04-07 18:51:17.920: E/AndroidRuntime(8113): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.site.testapp/com.site.testapp.MainActivity}: java.lang.ClassCastException: android.widget.ImageView cannot be cast to android.webkit.WebView
04-07 18:51:17.920: E/AndroidRuntime(8113): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2088)
04-07 18:51:17.920: E/AndroidRuntime(8113): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2113)
04-07 18:51:17.920: E/AndroidRuntime(8113): at android.app.ActivityThread.access$700(ActivityThread.java:139)
04-07 18:51:17.920: E/AndroidRuntime(8113): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1224)
04-07 18:51:17.920: E/AndroidRuntime(8113): at android.os.Handler.dispatchMessage(Handler.java:99)
04-07 18:51:17.920: E/AndroidRuntime(8113): at android.os.Looper.loop(Looper.java:137)
04-07 18:51:17.920: E/AndroidRuntime(8113): at android.app.ActivityThread.main(ActivityThread.java:4918)
04-07 18:51:17.920: E/AndroidRuntime(8113): at java.lang.reflect.Method.invokeNative(Native Method)
04-07 18:51:17.920: E/AndroidRuntime(8113): at java.lang.reflect.Method.invoke(Method.java:511)
04-07 18:51:17.920: E/AndroidRuntime(8113): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1004)
04-07 18:51:17.920: E/AndroidRuntime(8113): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:771)
04-07 18:51:17.920: E/AndroidRuntime(8113): at dalvik.system.NativeStart.main(Native Method)
04-07 18:51:17.920: E/AndroidRuntime(8113): Caused by: java.lang.ClassCastException: android.widget.ImageView cannot be cast to android.webkit.WebView
04-07 18:51:17.920: E/AndroidRuntime(8113): at me.publicize.testapp.MainActivity.onCreate(MainActivity.java:30)
04-07 18:51:17.920: E/AndroidRuntime(8113): at android.app.Activity.performCreate(Activity.java:5048)
04-07 18:51:17.920: E/AndroidRuntime(8113): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1094)
04-07 18:51:17.920: E/AndroidRuntime(8113): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2052)
04-07 18:51:17.920: E/AndroidRuntime(8113): ... 11 more