實現透明進度對話框(Transparent Progress Dialog)

通過自定義對話框, 修改佈局參數的 alpha 屬性, 可以實現透明的進度對話框(Transparent Progress Dialog).



創建 /res/layout/transparentprogressdialog.xml 定義包含進度條(ProgressBar)的對話框.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    android:paddingLeft="100dp"
    android:paddingRight="100dp"
    android:paddingTop="10dp"
    android:paddingBottom="10dp">

 <ProgressBar 
     android:layout_width="wrap_content"
        android:layout_height="wrap_content"/>

</LinearLayout>

修改主活動, 實現自定義對話框.

package com.AndroidProgressDialog;

import android.app.Activity;
import android.app.Dialog;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.SystemClock;
import android.view.View;
import android.view.WindowManager;
import android.widget.Button;

public class AndroidProgressDialog extends Activity {
 
 static final int CUSTOM_PROGRESSDIALOG_ID = 0;
 
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        Button buttonStart = (Button)findViewById(R.id.start);
        
        buttonStart.setOnClickListener(new Button.OnClickListener(){
         @Override
         public void onClick(View arg0) {
          // TODO Auto-generated method stub
          new asyncTaskUpdateProgress().execute(); 
         } 
        });
    }
    
    @Override
 protected Dialog onCreateDialog(int id) {
     Dialog dialog = null;
     switch(id) {
     case CUSTOM_PROGRESSDIALOG_ID:
      dialog = new Dialog(AndroidProgressDialog.this);
      dialog.setContentView(R.layout.transparentprogressdialog);
      dialog.setTitle("ProgressDialog");
      
      WindowManager.LayoutParams params = dialog.getWindow().getAttributes();
      params.alpha = 0.5f;
      dialog.getWindow().setAttributes(params);
      
      break;
     }
     
     return dialog;
 }

 public class asyncTaskUpdateProgress extends AsyncTask<Void, Integer, Void> {
     
     int progress;
        //ProgressDialog progressDialog;
        
        @Override
        protected void onPostExecute(Void result) {
         // TODO Auto-generated method stub 
         dismissDialog(CUSTOM_PROGRESSDIALOG_ID);
        }
        
        @Override
        protected void onPreExecute() {
         // TODO Auto-generated method stub
         progress = 0;
         showDialog(CUSTOM_PROGRESSDIALOG_ID);
        }
        
        @Override
        protected Void doInBackground(Void... arg0) {
         // TODO Auto-generated method stub
         while(progress<100){
          progress++;
          SystemClock.sleep(20);  
         }

         return null;
         
        }    
    }
}

主佈局 main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/hello" />
    <Button
        android:id="@+id/start"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="- Start -" />
    <ImageView
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:src="@drawable/ic_launcher"/>
        
</LinearLayout>