Android之WebView與URLConnection
阿新 • • 發佈:2019-01-03
demo
java程式碼:
public class MainActivity extends Activity implements View.OnClickListener {
private TextView mTextViewDetail;
private TextView mTextViewFalse;
private ProgressBar mProgressBarWeb;
private Button mButtonDetail;
private Button mButtonUrl;
//網頁的載入需要ConnectivityManager
private ConnectivityManager mManager;
private WebView mWebView;
private WebSettings mWs;
public static final int GET_URL_MESSAGE = 0x99;
//handler用於接收URLConnection傳遞的訊息
private Handler mHandler = new Handler(){
@Override
public void handleMessage(Message msg) {
switch (msg.what){
case GET_URL_MESSAGE:
mTextViewDetail.setText(msg.obj.toString());
break;
}
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mTextViewDetail = (TextView) findViewById(R.id.text_detail);
mTextViewFalse = (TextView) findViewById(R.id.text_web_false);
mProgressBarWeb = (ProgressBar) findViewById(R.id.progressBar_web);
mButtonDetail = (Button) findViewById(R.id.button_detail);
mManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
mButtonDetail.setOnClickListener(this );
mButtonUrl = (Button) findViewById(R.id.button_url);
mButtonUrl.setOnClickListener(this);
//WebView用來顯示網頁
mWebView = (WebView) findViewById(R.id.webView_test);
//mWs的作用是載入一個Zoom,功能是放大或縮小網頁
mWs = mWebView.getSettings();
mWs.setSupportZoom(true);
mWs.setBuiltInZoomControls(true);
//監聽網頁載入前後和網頁載入錯誤的事件
mWebView.setWebViewClient(new WebViewClient() {
@Override
public void onPageStarted(WebView view, String url, Bitmap favicon) {
super.onPageStarted(view, url, favicon);
mProgressBarWeb.setVisibility(View.VISIBLE);
}
@Override
public void onPageFinished(WebView view, String url) {
super.onPageFinished(view, url);
mProgressBarWeb.setVisibility(View.INVISIBLE);
}
@Override
public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
//super.onReceivedError(view, errorCode, description, failingUrl);
mWebView.setVisibility(View.GONE);
mTextViewFalse.setVisibility(View.VISIBLE);
Toast.makeText(getApplicationContext(), "同步載入失敗", Toast.LENGTH_SHORT).show();
}
});
//網頁載入中的監聽需要呼叫此方法
mWebView.setWebChromeClient(new WebChromeClient() {
@Override
public void onProgressChanged(WebView view, int newProgress) {
super.onProgressChanged(view, newProgress);
mProgressBarWeb.setProgress(newProgress);
}
});
}
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK) {
if (mWebView.canGoBack()) {
mWebView.goBack();
return true;
} else {
MainActivity.this.finish();
}
}
return super.onKeyDown(keyCode, event);
}
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.button_detail:
//loadUrl中傳入網頁地址
mWebView.loadUrl("http://www.bjlingzhuo.com/");
//NetWorkInfo用來得到網頁的一些資訊
NetworkInfo info = mManager.getActiveNetworkInfo();
if (info != null && info.isConnected()) {
mTextViewDetail.setText("網路型別:" + info.getTypeName());
} else {
mTextViewDetail.setText("無網路連線");
}
break;
case R.id.button_url:
new Thread(new Runnable() {
@Override
public void run() {
urlConnectServerLet();
}
}).start();
break;
default:
break;
}
}
/**
* URLConnection載入網頁的方法
*/
private void urlConnectServerLet() {
try {
URL url = new URL("http://www.bjlingzhuo.com");
//需要一個URLConnection開啟網頁
URLConnection connection = url.openConnection();
InputStream is = connection.getInputStream();
BufferedReader br = new BufferedReader(new InputStreamReader(is));
String line = br.readLine();
StringBuffer buffer = new StringBuffer();
while (line != null) {
buffer.append(line);
line = br.readLine();
}
is.close();
Message message = mHandler.obtainMessage();
message.what = GET_URL_MESSAGE;
message.obj = buffer.toString().trim();
mHandler.sendMessage(message);
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}
佈局:
ScrollView 中最多隻能載入一個控制元件
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<Button
android:id="@+id/button_detail"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="網路連線"/>
<Button
android:id="@+id/button_url"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="開啟Url連線"/>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="@+id/text_detail"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text=""/>
<ProgressBar
android:id="@+id/progressBar_web"
style="@style/Base.Widget.AppCompat.ProgressBar.Horizontal"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:visibility="invisible"/>
<TextView
android:id="@+id/text_web_false"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center"
android:text="載入失敗"
android:visibility="invisible"/>
<WebView
android:id="@+id/webView_test"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:visibility="visible">
</WebView>
</FrameLayout>
</LinearLayout>
</ScrollView>
結果演示:
WebView
URLConnection