android開發之歡迎界面

首先你得寫好xml文件，這也是最主要的。

然後，在activity中加入一個線程，延時2秒，用來跳轉到主界面。

activity中線程代碼如下：(順便檢測一下網絡是否打開）

[java] 
@Override 
    protected void onStart() { 
        super.onStart(); 
        if(<SPAN style="COLOR: #ff0000">isNetworkConnected()</SPAN>){ 
            new Thread(){ 
                @Override 
                public void run() { 
                    try { 
                        Thread.sleep(2000); 
                        Intent intent = new Intent(<SPAN style="COLOR: #ff0000">SplashActivity.this</SPAN>,<SPAN style="COLOR: #ff0000">CompusAssistMain.class</SPAN>); 
                        startActivity(intent); 
                        finish(); 
                    } catch (InterruptedException e) { 
                        e.printStackTrace(); 
                    } 
                     
                } 
            }.start(); 
        }else{ 
            //彈出對話框 讓用戶設置網絡  
            AlertDialog.Builder builder = new Builder(this); 
            builder.setTitle("設置網絡"); 
            builder.setMessage("網絡錯誤請設置網絡"); 
            builder.setPositiveButton("設置網絡", new OnClickListener() { 
                public void onClick(DialogInterface dialog, int which) { 
                    Intent intent = new Intent(); 
                    intent.setClassName(<SPAN style="COLOR: #ff6666">"com.android.settings"</SPAN>, <SPAN style="COLOR: #ff6666">"com.android.settings.WirelessSettings"</SPAN>); 
                    startActivity(intent); 
                } 
            }); 
            builder.setNegativeButton("取消", new OnClickListener() { 
                 
                public void onClick(DialogInterface dialog, int which) { 
                    finish(); 
                } 
            }); 
            builder.create().show(); 
        } 
    } 

@Override
 protected void onStart() {
  super.onStart();
  if(isNetworkConnected()){
   new Thread(){
    @Override
    public void run() {
     try {
      Thread.sleep(2000);
      Intent intent = new Intent(SplashActivity.this,CompusAssistMain.class);
      startActivity(intent);
      finish();
     } catch (InterruptedException e) {
      e.printStackTrace();
     }
     
    }
   }.start();
  }else{
   //彈出對話框 讓用戶設置網絡
   AlertDialog.Builder builder = new Builder(this);
   builder.setTitle("設置網絡");
   builder.setMessage("網絡錯誤請設置網絡");
   builder.setPositiveButton("設置網絡", new OnClickListener() {
    public void onClick(DialogInterface dialog, int which) {
     Intent intent = new Intent();
     intent.setClassName("com.android.settings", "com.android.settings.WirelessSettings");
     startActivity(intent);
    }
   });
   builder.setNegativeButton("取消", new OnClickListener() {
    
    public void onClick(DialogInterface dialog, int which) {
     finish();
    }
   });
   builder.create().show();
  }
 }檢測網絡的類isNetWorkConnected():

[java] 
<SPAN style="WHITE-SPACE: pre"> </SPAN>/**
     * 判斷系統的網絡是否可用
     * @return
     */ 
    private boolean isNetworkConnected(){ 
        ConnectivityManager cm =    (ConnectivityManager) getSystemService(CONNECTIVITY_SERVICE); 
        NetworkInfo info =cm.getActiveNetworkInfo(); 
        if(info!=null&&info.isConnected()){ 
            return true; 
        }else { 
            return false ; 
        } 
     

 /**
  * 判斷系統的網絡是否可用
  * @return
  */
 private boolean isNetworkConnected(){
  ConnectivityManager cm = (ConnectivityManager) getSystemService(CONNECTIVITY_SERVICE);
  NetworkInfo info =cm.getActiveNetworkInfo();
  if(info!=null&&info.isConnected()){
   return true;
  }else {
   return false ;
  }
 這樣就完成了一個歡迎界面，給自已的應用加點色彩。當然還要添加配置在Manifest文件中

[html]
<activity 
            android:name="com.yan.compusassist.SplashActivity" 
            android:label="@string/application_name" > 
            <intent-filter> 
                <action android:name="android.intent.action.MAIN" /> 
                <category android:name="android.intent.category.LAUNCHER" /> 
            </intent-filter> 
        </activity> 

<activity
            android:name="com.yan.compusassist.SplashActivity"
            android:label="@string/application_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>這樣它就會打開應用，啟動第一個activity 界面。