Android[初級教程]第十三章 ProgressDialog控制項

這次我們學習ProgressDialog控制項,還是拿西遊記來說,唐僧被妖怪們抓去了,那悟空得去救啊,但妖怪肯定不讓啦,這就經過了一番打鬥,當然,妖怪肯定打不過悟空啦,我們就用ProgressDialog來類比打妖怪的過程,設定為100隻妖怪,打完這100隻妖怪才能救出師傅.看圖:

 

 

 

呵呵,這次悟空沒出手,讓八戒跟沙僧搶了回頭功,來看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="match_parent" 
    android:layout_height="match_parent"> 
    <Button android:text="悟空去救師傅" android:id="@+id/wukong" 
        android:layout_width="wrap_content" android:layout_height="wrap_content"></Button> 
    <Button android:text="八戒去救師傅" android:id="@+id/bajie" 
        android:layout_width="wrap_content" android:layout_height="wrap_content"></Button> 
    <Button android:text="沙僧去救師傅" android:id="@+id/shaseng" 
        android:layout_width="wrap_content" android:layout_height="wrap_content"></Button> 
 
</LinearLayout> 

還是老樣子,定義了幾個按鈕,接下來看Activity的java源碼:

 
import android.app.Activity; 
import android.app.ProgressDialog; 
import android.os.Bundle; 
import android.os.Handler; 
import android.os.Message; 
import android.view.View; 
import android.view.View.OnClickListener; 
import android.widget.Button; 
import android.widget.Toast; 
 
public class ProgressDialogDemo extends Activity implements OnClickListener 
{ 
    private ProgressDialog Dialog; 
    private Handler mhandler; 
    @Override 
    protected void onCreate(Bundle savedInstanceState) 
    { 
        // TODO Auto-generated method stub 
        super.onCreate(savedInstanceState); 
        setContentView(R.layout.progressdialog); 
 
        Button wukong = (Button) findViewById(R.id.wukong); 
        wukong.setOnClickListener(this); 
 
        Button bajie = (Button) findViewById(R.id.bajie); 
        bajie.setOnClickListener(this); 
 
        Button shaseng = (Button) findViewById(R.id.shaseng); 
        shaseng.setOnClickListener(this); 
    } 
 
    @Override 
    public void onClick(View v) 
    { 
        //設定Handler對象,主要是處理新開線程完畢後交給主線程來處理的資料 
        mhandler = new Handler(){ 
            @Override 
            public void handleMessage(Message msg) 
            { 
                String name =(String)msg.obj; 
                Toast.makeText(ProgressDialogDemo.this, name + "把師傅救出來了", 1).show(); 
            } 
        }; 
        //建立ProgressDialog對象 
        Dialog = new ProgressDialog(this); 
        //設定ProgressDialog的樣式為進度條 
        Dialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL); 
        //設定ProgressDialog的最大值為100,這裡就是100隻小妖怪啦 
        Dialog.setMax(100); 
        //設定ProgressDialog不能取消,你不能半途而廢啊,當然要100隻打完啦 
        Dialog.setCancelable(false); 
         
        String name = null; 
         
        switch (v.getId()) 
        { 
        case R.id.wukong: 
            //設定名字,看是誰在打妖怪啊 
            name = "孫悟空"; 
            Dialog.setTitle(name); 
            //圖片 
            Dialog.setIcon(R.drawable.wukong); 
            //訊息 
            Dialog.setMessage("悟空在打妖怪"); 
            //自訂打鬥的方法 
            doFlight(name); 
 
            break; 
 
        case R.id.bajie: 
             
            //同上 
            name = "豬八戒"; 
            Dialog.setTitle(name); 
            Dialog.setIcon(R.drawable.bajie); 
            Dialog.setMessage("八戒在打妖怪"); 
            doFlight(name); 
 
            break; 
 
        case R.id.shaseng: 
             
            //同上 
            name = "沙和尚"; 
            Dialog.setTitle(name); 
            Dialog.setIcon(R.drawable.shaseng); 
            Dialog.setMessage("沙僧在打妖怪"); 
            doFlight(name); 
 
            break; 
        } 
 
         
 
    } 
 
    private void doFlight(final String name) 
    { 
        //顯示ProgressDialog 
        Dialog.show(); 
         
        //新開一條線程 
        new Thread() 
        { 
            //打完妖怪的數量 
            int count = 0; 
            public void run() 
            { 
                try 
                { 
                    //打完妖怪小於100隻的時候啟動並執行方法 
                    while(count <= 100){ 
                        Dialog.setProgress(count++); 
                        //睡眠0.2秒,你也得讓他們休息一下啊,呵呵 
                        Thread.sleep(200); 
                    } 
                    Dialog.cancel(); 
                     
                    //給handler發送訊息,看是誰在打妖怪,handler是主線程中的 
                    Message message = new Message(); 
                    message.obj = name; 
                    mhandler.sendMessage(message); 
 
                } catch (InterruptedException e) 
                { 
                    Dialog.cancel(); 
                } 
                 
            }; 
 
        }.start(); 
         
    } 
} 

這裡面涉及了子線程和主線程的通訊,通過Handler可以將子線程啟動並執行資料最終交給主線程,線程這一章我們會在接下來講,OK,這一章也講完了,謝謝

 

摘自：kangkangz4的專欄