设置AlertBox标题栏背景颜色

如何更改警报框标题栏的背景颜色？

AlertDialog.Builder alert=new AlertDialog.Builder(getParent());
alert.setTitle("sample");
alert.show();

最简单的方法是通过创建一个扩展对话框的类来子类化对话框并实现以样式为参数的构造函数。然后对其进行自定义布局。

显示对话框的代码：

private void showDialog()
{
    Custom_Dialog dialog = new Custom_Dialog(this, R.style.myCoolDialog);

    dialog.setContentView(R.layout.custom_dialog);
    dialog.setTitle("Custom Dialog");

    TextView text = (TextView) dialog.findViewById(R.id.text);
    text.setText("Hello, this is a custom dialog!");
    ImageView image = (ImageView) dialog.findViewById(R.id.image);
    image.setImageResource(R.drawable.icon);

    dialog.show();  
}

子类的代码：

package com.stackoverflow;

import android.app.Dialog;
import android.content.Context;

public class Custom_Dialog extends Dialog {

    protected Custom_Dialog(Context context, int theme) {
        super(context, theme);
        // TODO Auto-generated constructor stub
    }

}

the style：myCoolDialog.xml

<resources>
    <style name="myCoolDialog" parent="android:Theme.Dialog"> 
        <item name="android:windowBackground">@drawable/blue</item>
        <item name="android:colorForeground">#f0f0</item> 
     </style> 
</resources>

并最后layout:custom_dialog.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:id="@+id/layout_root"
              android:orientation="horizontal"
              android:layout_width="fill_parent"
              android:layout_height="fill_parent"
              android:padding="10dp"
              >
    <ImageView android:id="@+id/image"
               android:layout_width="wrap_content"
               android:layout_height="fill_parent"
               android:layout_marginRight="10dp"
               />
    <TextView android:id="@+id/text"
              android:layout_width="wrap_content"
              android:layout_height="fill_parent"
              android:textColor="#FFF"
              />
</LinearLayout>