話不多說,代碼:
XML布局檔案,只是一個Demo,所以就一個Button.
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:paddingBottom="@dimen/activity_vertical_margin" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" tools:context=".MainActivity" > <Button android:id="@+id/button_id" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="@string/button_text" /></RelativeLayout>
JAVA代碼:
package com.example.dialog_alpha_demo;import android.os.Bundle;import android.app.Activity;import android.app.AlertDialog;import android.view.Gravity;import android.view.Menu;import android.view.View;import android.view.View.OnClickListener;import android.view.Window;import android.view.WindowManager;import android.widget.Button;public class MainActivity extends Activity {private Button mButton;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);mButton = (Button) this.findViewById(R.id.button_id);mButton.setOnClickListener(listener);}@Overridepublic boolean onCreateOptionsMenu(Menu menu) {// Inflate the menu; this adds items to the action bar if it is present.getMenuInflater().inflate(R.menu.main, menu);return true;}View.OnClickListener listener = new OnClickListener() {@Overridepublic void onClick(View v) {// TODO Auto-generated method stubShowDialog();}};private void ShowDialog() {AlertDialog mDialog = new AlertDialog.Builder(this).setIcon(R.drawable.ic_launcher).setTitle("溫馨提示").setMessage("透明對話方塊").setPositiveButton("確定", null).create();// 擷取對話方塊的Window對象Window mWindow = mDialog.getWindow();WindowManager.LayoutParams lp = mWindow.getAttributes();// 透明度的範圍為:0.0f-1.0f;0.0f表示完全透明,1.0f表示完全不透明(系統預設的就是這個)。lp.alpha = 0.35f;//設定對話方塊在螢幕的底部顯示,當然還有上下左右,任意位置//mWindow.setGravity(Gravity.LEFT);mWindow.setGravity(Gravity.BOTTOM); /* * * 這裡是設定位移量,這裡的x,y並不是相對於螢幕的絕對座標,而是相對於對話方塊在中心位置(預設的對話方塊一般顯示在螢幕的中心)而言的lp.x = -20;// 設定水平位移量lp.y = -90;// 設定豎直位移量*/// 設定Window的屬性mWindow.setAttributes(lp);mDialog.show();}}
顯示結果為: