ProgressDialog 使用
ProgressDialog

[功能]
ProgressDialog 也是一种Dialog
一般 在出现ProgressDialog 后台都会再开辟Thread 来做一些耗时的工作 我演示的是从100数到0 这段时间既不太长 不用浪费时间等待 同时 也能明显地看出效果



[代码]
1. ProgressDialog 使用

public void startProgress(){    //to start Progress    pd = ProgressDialog.show(this, "loop from 100 to 0!", "is looping...", true,    false);    //pd.setIcon(R.drawable.icon);    }

2. 开辟一个Thread来从100数到0 在数完后 关闭ProgressDialog

public class TaskLoop implements Runnable {@Overridepublic void run() {// TODO Auto-generated method stubloop(5000);messageListener.sendEmptyMessage(TASK_LOOP_COMPLETE);}        }public void loop(long i){    long j = i;    while(j>0){    Log.d("tag",j+"");        j = j-1;}    }

3. 运行该Thread

Thread loop = new Thread(new TaskLoop());loop.start();

4.定义一个Handler 用于接受 关闭ProgressDialog 的通知

private Handler messageListener = new Handler(){    public void handleMessage(Message msg) {switch(msg.arg1){case TASK_LOOP_COMPLETE:pd.dismiss();break;}}    };

[所有代码]

public class MyProgressUsage extends Activity {public final static int TASK_LOOP_COMPLETE = 0;ProgressDialog pd;TextView tv;/** Called when the activity is first created. */    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);                findViewById(R.id.start).setOnClickListener(new OnClickListener(){public void onClick(View v) {// TODO Auto-generated method stubstartLoop();}        });    }        public void startLoop(){        startProgress();        Thread loop = new Thread(new TaskLoop());    loop.start();    }            public class TaskLoop implements Runnable {@Overridepublic void run() {// TODO Auto-generated method stubloop(5000);messageListener.sendEmptyMessage(TASK_LOOP_COMPLETE);}        }        public void startProgress(){    //to start Progress    pd = ProgressDialog.show(this, "loop from 100 to 0!", "is looping...", true,    false);    //pd.setIcon(R.drawable.icon);    }        //to do some time-cost task    public void loop(long i){    long j = i;    while(j>0){    Log.d("tag",j+"");        j = j-1;}    }        private Handler messageListener = new Handler(){    public void handleMessage(Message msg) {switch(msg.arg1){case TASK_LOOP_COMPLETE:pd.dismiss();break;}}    };    }

http://dl.iteye.com/upload/picture/pic/52676/11cd6622-cb13-337a-bd52-007185e972c0.png
over!