Android實作webView元件

Android實作webView元件

程式碼:

public class MainActivity extends Activity {

     @Override

     public void onBackPressed() {

         // TODO Auto-generated method stub

         // mwv.goBack(); //回上一頁

         // super.onBackPressed(); //離開

         if (mwv.canGoBack())

              mwv.goBack();

         else

              System.exit(0);

     }

     private WebView mwv;

     private ProgressDialog pd;

     private Button mbtn;

     private Button mbtn2;

     @Override

     protected void onCreate(Bundle savedInstanceState) {

         super.onCreate(savedInstanceState);

         setContentView(R.layout.activity_main);

         mwv = (WebView) findViewById(R.id.webView1);

         // 瀏覽網路需要權限 android.permission.INTERNET

         // String url = "http://www.tcfst.org.tw";

         // mwv.loadUrl(url);

         mwv.setWebViewClient(new myvebviewclient()); // 設定 web client

         pd = new ProgressDialog(this);// 設定progress bar

         mbtn = (Button) findViewById(R.id.button1);

         mbtn.setOnClickListener(new Button.OnClickListener() {

              @Override

              public void onClick(View v) {

                  // TODO Auto-generated method stub

                  Log.e("but1", "onClick");

                  pd.setMessage("Loading...");

                  pd.setCanceledOnTouchOutside(false); // 設定 使用者無法 按到旁邊而關掉

                  pd.show();

                  String url = "http://tw.yahoo.com";

                  // String url = "file:///android_asset/demo.html";

                  // //瀏覽使用設定的html檔案

                  mwv.loadUrl(url);

              }

         });

     mbtn2 = (Button) findViewById(R.id.button2);

         mbtn2.setOnClickListener(new Button.OnClickListener() {

              @Override

              public void onClick(View v) {

                  // TODO Auto-generated method stub

                  Log.e("but2", "onClick");

                  pd.setMessage("Loading...");

                  pd.setCanceledOnTouchOutside(false); // 設定 使用者無法 按到旁邊而關掉

                  pd.show();

                  // String url = "http://tw.yahoo.com";

                  String url = "file:///android_asset/demo.html"; // 瀏覽使用設定的html檔案

                  mwv.loadUrl(url);

              }

         });

     }

private class myvebviewclient extends WebViewClient {

         @Override

         public boolean shouldOverrideUrlLoading(WebView view, String url) {

              // TODO Auto-generated method stub

              view.loadUrl(url);

              return true;

         }

         @Override

         public void onPageFinished(WebView view, String url) {

              // TODO Auto-generated method stub

              // super.onPageFinished(view, url);

              if (pd.isShowing())

                  pd.dismiss();

         }

     }

}

說明:

1.  需開啟網路使用權限; <uses-permission android:name="android.permission.INTERNET"/>

2.      需建立一個繼承WebViewClient的類別,使用該類別來當使用者存取網址及webView的中介

3.      點選Button1及Button2會各自開啟兩個不同的網頁,並將其呈現於webView上

4.      若不使用WebViewClient則系統會詢問使用者,要使用目前系統上的哪一個瀏覽器來開啟網頁

利用intent呼叫Activity及傳送資料

利用intent呼叫Activity及傳送資料

 

Activity1程式碼

public class Activity1 extends Activity

{

     private Button bt1;

     @Override

     protected void onCreate(Bundle savedInstanceState)

     {

         super.onCreate(savedInstanceState);

         setContentView(R.layout.activity_activity1);

       

        

         bt1 = (Button) findViewById(R.id.button1);

         bt1.setOnClickListener(new Button.OnClickListener()

         {

              @Override

              public void onClick(View v)

              {

                  // TODO Auto-generated method stub

                  Intent it = new Intent();

                  it.setClass(Activity1.this, Activity2.class);

                  it.putExtra("pass", "ispassword");

                  it.putExtra("user", "ZCFang");

                  startActivity(it);

              }

         });

     }

}

說明:

1.使用intent.setClass設定欲開啟的Activity

2.使用intent.putExtra 放入欲傳送的資訊,若資料量很大也可以選擇使用Bundle物件加入資訊,再藉由intent傳送

3.使用startActivity傳送intent並開啟指定的Activity

Activity2程式碼

public class Activity2 extends Activity

{

     private Button bt2;

     @Override

     protected void onCreate(Bundle savedInstanceState)

     {

         super.onCreate(savedInstanceState);

         setContentView(R.layout.activity_activity2);

        

         Bundle b = getIntent().getExtras();

         String str = b.getString("user") + " : " + b.getString("pass");

         Toast.makeText(this, str, Toast.LENGTH_LONG).show();

         bt2 = (Button) findViewById(R.id.button2);

         bt2.setOnClickListener(new Button.OnClickListener()

         {

              @Override

              public void onClick(View v)

              {

                  // TODO Auto-generated method stub

                  Intent it = new Intent();

                  it.setClass(Activity2.this, Activity1.class);

                  startActivity(it);

              }

         });

     }

}

說明:

1.使用Bundle接收使用者傳送過來的資訊

2.再依資料型別從Bundle物件中取出資料