Android开发中Dialog对话框的使用

Android开发中Dialog对话框的使用

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 " ? >< LinearLayoutxmlns:android = " http://schemas.android.com/apk/res/android " android:orientation = " horizontal " android:layout_width = " fill_parent " android:layout_height = " fill_parent " > < ImageViewandroid: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 >

　　

　　到这里自定义对话框的创建就结束了，想要什么样子的对话框完全凭你自己的想像。