Dialog是android开发过程中最常用到的组件之一，它包括以下几种类型：
- 警告对话框：Alertialog
- 进度对话框：ProgressDialog
- 日期选择对话框：DatePickerDialog
- 时间选择对话框：TimePickerDialog
- 自定义对话框：从Dialog继承
Dialog的创建方式有两种：
一是直接new一个Dialog对象，然后调用Dialog对象的show和dismiss方法来控制对话框的显示和隐藏。
二是在Activity的onCreateDialog(int id)方法中创建Dialog对象并返回，然后调用Activty的showDialog(int id)和dismissDialog(int id)来显示和隐藏对话框。
区别在于通过第二种方式创建的对话框会继承Activity的属性，比如获得Activity的menu事件等。
使用AlertDialog可以创建普通对话框、带列表的对话框以及带单选按钮和多选按钮的对话框。
普通对话框
效果如下：
代码：
//创建builder
AlertDialog.Builder builder = new AlertDialog.Builder(DialogSampleActivity.this);
builder.setTitle("普通对话框") //标题
.setIcon(R.drawable.ic_launcher) //icon
.setCancelable(false) //不响应back按钮
.setMessage("这是一个普通对话框") //对话框显示内容
//设置按钮
.setPositiveButton("确定", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
Toast.makeText(DialogSampleActivity.this, "点击了确定按钮", Toast.LENGTH_SHORT).show();
}
})
.setNeutralButton("中立", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
Toast.makeText(DialogSampleActivity.this, "点击了中立按钮", Toast.LENGTH_SHORT).show();
}
})
.setNegativeButton("取消", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
Toast.makeText(DialogSampleActivity.this, "点击了取消按钮", Toast.LENGTH_SHORT).show();
}
});
//创建Dialog对象
AlertDialog dlg = builder.create();
return dlg;
带列表的对话框
效果图：
代码：
final CharSequence[] items = { "Item1", "Item2", "Item3" };
// 创建builder
AlertDialog.Builder builder = new AlertDialog.Builder(
DialogSampleActivity.this);
builder.setTitle("列表对话框") // 标题
.setIcon(R.drawable.ic_launcher) // icon
.setCancelable(false) // 不响应back按钮
.setItems(items, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
Toast.makeText(DialogSampleActivity.this,
"选择了" + items[which], Toast.LENGTH_SHORT)
.show();
}
});
// 创建Dialog对象
AlertDialog dlg = builder.create();
return dlg;
带单选按钮的列表对话框
只需将setItems替换为：
.setSingleChoiceItems(items, -1, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
Toast.makeText(DialogSampleActivity.this,
"选择了" + items[which], Toast.LENGTH_SHORT)
.show();
}
});
这里多了一个参数-1，代表默认选中第几项，-1表示默认不选中
带复选框的列表对话框
只需将setItems替换为：
.setMultiChoiceItems(items, checked, new DialogInterface.OnMultiChoiceClickListener() {
@Override
public void onClick(DialogInterface dialog, int which, boolean isChecked) {
Toast.makeText(DialogSampleActivity.this,
"选择了" + items[which], Toast.LENGTH_SHORT)
.show();
}
});
参数checked伟boolean数组，表示默认哪些复选框是被选中的。
另外，如果你想要获取list中哪些项是被选中的，你需要：
//获得ListView
ListView list = dlg.getListView();
//判断第i项是否被选中，为真表示被选中，为假表示没有选中
list.getCheckedItemPositions().get(i)
日期选择对话框
效果图：
代码：
Calendar calendar = Calendar.getInstance();
DatePickerDialog.OnDateSetListener dateListener =
new DatePickerDialog.OnDateSetListener() {
@Override
public void onDateSet(DatePicker datePicker,
int year, int month, int dayOfMonth) {
Toast.makeText(DialogSampleActivity.this,
year + "年" + (month+1) + "月" + dayOfMonth + "日", Toast.LENGTH_SHORT)
.show();
}
};
DatePickerDialog dlg = new DatePickerDialog(
DialogSampleActivity.this,
dateListener,
calendar.get(Calendar.YEAR),
calendar.get(Calendar.MONTH),
calendar.get(Calendar.DAY_OF_MONTH));
return dlg;
时间选择对话框
效果图：
代码：
Calendar calendar = Calendar.getInstance();
TimePickerDialog.OnTimeSetListener timeListener =
new TimePickerDialog.OnTimeSetListener() {
@Override
public void onTimeSet(TimePicker timePicker, int hourOfDay, int minute) {
Toast.makeText(DialogSampleActivity.this,
hourOfDay + ":" + minute, Toast.LENGTH_SHORT).show();
}
};
TimePickerDialog dlg = new TimePickerDialog(
DialogSampleActivity.this,
timeListener,
calendar.get(Calendar.HOUR_OF_DAY),
calendar.get(Calendar.MINUTE),
true);
return dlg;
自定义对话框
效果图：
步骤：
1、创建对话框的布局文件
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<!-- 标题栏 -->
<LinearLayout
android:id="@+id/dlg_priority_titlebar"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true">
<ImageView
android:src="@drawable/star_gray"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="5dip"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="选择任务优先级"
android:layout_gravity="center_vertical"/>
</LinearLayout>
<!-- 任务优先级 -->
<ListView
android:id="@+id/dlg_priority_lvw"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@id/dlg_priority_titlebar"
android:background="@drawable/layout_home_bg">
</ListView>
</RelativeLayout>
2、因为该布局中使用了自定义的ListView，所以再为ListView创建布局文件
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<ImageView
android:id="@+id/list_priority_img"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:layout_margin="5dip"
/>
<TextView
android:id="@+id/list_priority_value"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:textSize="28dip"
android:textColor="@drawable/black"/>
</LinearLayout>
3、创建自定义Dialog类PriorityDlg继承自Dialog
public class PriorityDlg extends Dialog {
private Context context;
private ListView dlg_priority_lvw = null;
public PriorityDlg(Context context) {
super(context);
this.context = context;
// TODO Auto-generated constructor stub
}
public PriorityDlg(Context context, int theme) {
super(context, theme);
this.context = context;
}
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
//设置对话框使用的布局文件
this.setContentView(R.layout.dlg_priority);
dlg_priority_lvw = (ListView) findViewById(R.id.dlg_priority_lvw);
// 设置ListView的数据源
SimpleAdapter adapter = new SimpleAdapter(context, getPriorityList(),
R.layout.lvw_priority, new String[] { "list_priority_img",
"list_priority_value" }, new int[] {
R.id.list_priority_img, R.id.list_priority_value });
dlg_priority_lvw.setAdapter(adapter);
// 为ListView设置监听器
dlg_priority_lvw
.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> arg0, View arg1,
int arg2, long arg3) {
}
});
}
/**
* 得到ListView数据源
*
* @return
*/
private List<HashMap<String, Object>> getPriorityList() {
List<HashMap<String, Object>> priorityList = new ArrayList<HashMap<String, Object>>();
HashMap<String, Object> map1 = new HashMap<String, Object>();
map1.put("list_priority_img", R.drawable.priority_not_important);
map1.put("list_priority_value", context.getResources().getString(
R.string.dlg_priority_not_important));
priorityList.add(map1);
HashMap<String, Object> map2 = new HashMap<String, Object>();
map2.put("list_priority_img", R.drawable.priority_general);
map2.put("list_priority_value", context.getResources().getString(
R.string.dlg_priority_general));
priorityList.add(map2);
HashMap<String, Object> map3 = new HashMap<String, Object>();
map3.put("list_priority_img", R.drawable.priority_important);
map3.put("list_priority_value", context.getResources().getString(
R.string.dlg_priority_important));
priorityList.add(map3);
HashMap<String, Object> map4 = new HashMap<String, Object>();
map4.put("list_priority_img", R.drawable.priority_very_important);
map4.put("list_priority_value", context.getResources().getString(
R.string.dlg_priority_very_important));
priorityList.add(map4);
return priorityList;
}
}
4、创建自定义对话框
PriorityDlg dlg = new PriorityDlg(SimpleTaskActivity.this, R.style.dlg_priority);
return dlg;
这里的R.style.dlg_priority设置了对话框使用的样式文件，只是让对话框去掉标题栏，当然你也可以通过代码来完成这种效果：
<?xml version="1.0" encoding="utf-8"?>
<resources>
<!-- 对话框样式 -->
<style name="dlg_priority" parent="@android:Theme.Dialog">
<item name="android:windowNoTitle">true</item>
</style>
</resources>