：Android Market的 Loading效果

在Android中,要实现Loading效果，一般情况下都使用ProgressDialog控件。ApiDemos/src/com/example/android/apis/view/ProgressBar3.java 提供两个demo:

仔细看了Android Market，发现却是不一样的，请看截图:

那到底如何实现呢？首先，我们创建一个布局文件,

res/layout/fullscreen_loading_indicator.xml, 其内容如下:

 

<? xml version = " 1.0 "  encoding = " utf-8 " ?>
< LinearLayout
  xmlns:android = " http://schemas.android.com/apk/res/android "
      android:gravity = " center_vertical|center_horizontal "
    android:orientation = " horizontal "
    android:id = " @+id/fullscreen_loading_style "
    
    android:layout_width = " fill_parent "
    android:layout_height = " fill_parent "   
   >
   < ProgressBar 
  android:layout_gravity = " center_vertical "
android:layout_width = " wrap_content "
android:layout_height = " wrap_content "
style = " ?android:attr/progressBarStyleSmall "
/>

< TextView
    android:id = " @+id/current_action "
    android:layout_width = " wrap_content "
    android:layout_height = " wrap_content "
    android:layout_marginLeft = " 5.0dip "
    android:text = " @+string/loading "
/>
</ LinearLayout >

然后在main.xml 把它include 进来

<? xml version = " 1.0 "  encoding = " utf-8 " ?>
< LinearLayout xmlns:android = " http://schemas.android.com/apk/res/android "
    android:orientation = " vertical "  android:layout_width = " fill_parent "
    android:layout_height = " fill_parent " >
     < LinearLayout android:orientation = " vertical "  
        android:id = " @+id/main_info "
        android:visibility = " gone "  
        android:layout_width = " fill_parent "
        android:layout_height = " fill_parent " >
         < TextView android:layout_width = " fill_parent "
        android:layout_height = " fill_parent "
        android:text = " abc " ></ TextView >
     </ LinearLayout >
     < LinearLayout android:orientation = " vertical "  
        android:id = " @+id/main_Loading "
        
        android:layout_width = " fill_parent "
        android:layout_height = " fill_parent " >
         < include android:visibility = " visible "  
            android:layout_width = " fill_parent "
            android:layout_height = " fill_parent "  
            layout = " @layout/fullscreen_loading_style "   />
     </ LinearLayout >
</ LinearLayout >

主程序：

package  com.tymx.fullloading;

import  android.app.Activity;
import  android.os.Bundle;
import  android.os.Handler;
import  android.os.Message;
import  android.view.View;
import  android.widget.LinearLayout;

public   class  myFullLoading  extends  Activity {
     /**  Called when the activity is first created.  */
     private  LinearLayout mLoadingLayout;

    @Override
     public   void  onCreate(Bundle savedInstanceState) {
         super .onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
         final  Handler handler  =   new  Handler(){

            @Override
             public   void  handleMessage(Message msg) {
                 //  TODO Auto-generated method stub
                 super .handleMessage(msg);
                 if  (msg.what == 1 ){
                    mLoadingLayout  =  (LinearLayout)findViewById(R.id.fullscreen_loading_style);
                    mLoadingLayout.setVisibility(View.GONE);
                    
                    LinearLayout mMain  =  (LinearLayout)findViewById(R.id.main_info);
                    mMain.setVisibility(View.VISIBLE);
                }                
                
            }
            
        };
         new  Thread(){
             public   void  run(){
                 for  ( int  i = 0 ;i < 1000 ;i ++ ){
                    System.out.print(i + "" );
                }
                Message msg  =  handler.obtainMessage( 1 , " flash " );
                handler.sendMessage(msg);
            }            
        }.start();
            
    }
}

运行的效果为: