AlertDialog详解
AlertDialog,对话框,用于给用户提示信息或者做出一些选择,同时它也是其他Dialog的的父类:比如ProgressDialog,TimePickerDialog等。
AlertDialog的父类是:Dialog。
AlertDialog在使用时并不能像其他的控件一样,例如Toast和Notification,这些控件是new出来的,但是AlertDialog不能通过new来使用,而是需要使用到该类中的一个静态内部类:public static class Builder,然后来调用AlertDialog里的相关方法,来对AlertDialog进行设置,最后调用show()方法来显示我们的AlertDialog对话框。
使用对话框的步骤:
1.创建AlertDialog.Builder对象
2.给对话框添加内容,icon,title,message,button等等
3.调用AlertDialog.Builder对象的creat()方法,创建这个对话框对象,并用show()方法显示。
实践一下:
先定义一个布局文件,添加几个button,用于点击显示对话框:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"xmlns:tools="http://schemas.android.com/tools"android:id="@+id/activity_main5"android:layout_width="match_parent"android:layout_height="match_parent"android:orientation="vertical"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="com.quaie.wms.myapplication.Main5Activity">
<!--对话框选择--><Buttonandroid:id="@+id/AlertDialog01"android:layout_width="match_parent"android:layout_height="40dp"android:layout_gravity="center"android:text="一个基本的对话框" /><Buttonandroid:id="@+id/AlertDialog02"android:layout_width="match_parent"android:layout_height="40dp"android:layout_gravity="center"android:text="在对话框中添加一个列表" /><Buttonandroid:id="@+id/AlertDialog03"android:layout_width="match_parent"android:layout_height="40dp"android:layout_gravity="center"android:text="在对话框中添加单选列表" /><Buttonandroid:id="@+id/AlertDialog04"android:layout_width="match_parent"android:layout_height="40dp"android:layout_gravity="center"android:text="在对话框中添加复选列表" /><Buttonandroid:id="@+id/AlertDialog05"android:layout_width="match_parent"android:layout_height="40dp"android:layout_gravity="center"android:text="显示一个自定义的对话框" /></LinearLayout>
在activity中声明这些控件,此处省略千行。
声明对话框对象:
private AlertDialog mDialog = null;private AlertDialog.Builder mBuilder = null;
显示一个基本的对话框,包括icon,标题,包含的信息还有三个按钮,积极的,消极的,中立的:
//开始默念mDialog = null;//第一步mBuilder = new AlertDialog.Builder(Main5Activity.this);//第二步mDialog = mBuilder.setIcon(R.mipmap.iv_lol_icon1).setTitle("系统提示:").setMessage("你已经进入对话框范围。").setPositiveButton("确定", new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {Toast.makeText(Main5Activity.this, "你点击了确定按钮", Toast.LENGTH_SHORT).show();}}).setNegativeButton("取消", new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {Toast.makeText(Main5Activity.this, "你点击了取消按钮", Toast.LENGTH_SHORT).show();}}).setNeutralButton("One More", new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {Toast.makeText(Main5Activity.this, "你点击了中立按钮", Toast.LENGTH_SHORT).show();}})//第三步.create();mDialog.show();
在对话框中添加一个列表,其实很简单,不需要listview也能实现,用android自带的setItems()就可以。下面是代码:
//准备数据源final String[] names = new String[]{"Teemo", "Noble", "Able", "Bear", "Pen", "Sibley", "Haber", "Teemo", "Noble", "Able", "Bear", "Pen", "Sibley", "Haber", "Teemo", "Noble", "Able", "Bear", "Pen", "Sibley", "Haber"};//默念三部mDialog = null;mBuilder = new AlertDialog.Builder(Main5Activity.this);mDialog = mBuilder.setIcon(R.mipmap.iv_lol_icon2).setTitle("取一个你喜欢的名字吧")//这里添加一个列表.setItems(names, new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {Toast.makeText(Main5Activity.this, "你选取的名字是:" + names[which], Toast.LENGTH_SHORT).show();}}).create();mDialog.show();
同样的,在对话框中添加一个单选列表,用setSingleChoiceItems():
final String[] names03 = new String[]{"Teemo", "Noble", "Able", "Bear", "Pen", "Sibley", "Haber", "Teemo", "Noble", "Able", "Bear", "Pen", "Sibley", "Haber", "Teemo", "Noble", "Able", "Bear", "Pen", "Sibley", "Haber"};mDialog = null;mBuilder = new AlertDialog.Builder(Main5Activity.this);mDialog = mBuilder.setIcon(R.mipmap.iv_lol_icon3).setTitle("再来选择一次吧").setSingleChoiceItems(names03, 0, new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {Toast.makeText(Main5Activity.this, "你选取的名字是:" + names03[which], Toast.LENGTH_SHORT).show();}}).setPositiveButton("确定", new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {Toast.makeText(Main5Activity.this, "确定", Toast.LENGTH_SHORT).show();}}).create();mDialog.show();
复选列表只是多了一个给按钮初始化的步骤:
final String[] names04 = new String[]{"Teemo", "Noble", "Able", "Bear", "Pen", "Sibley", "Haber","Teemo1", "Noble1", "Able1", "Bear1", "Pen1", "Sibley1", "Haber1"};//给复选按钮赋初始值boolean[] checkItems = new boolean[names04.length];for (int i = 0; i < names04.length; i++) {if (i < names04.length / 2) {checkItems[i] = false;} else {checkItems[i] = true;}}mDialog = null;mBuilder = new AlertDialog.Builder(Main5Activity.this);mDialog = mBuilder.setIcon(R.mipmap.iv_lol_icon3).setTitle("再来选择一次吧").setMultiChoiceItems(names04, checkItems, new DialogInterface.OnMultiChoiceClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which, boolean isChecked) {Toast.makeText(Main5Activity.this, "你选取的名字是:" + names04[which], Toast.LENGTH_SHORT).show();}}).setPositiveButton("确定", new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {Toast.makeText(Main5Activity.this, "确定", Toast.LENGTH_SHORT).show();}}).create();mDialog.show();
在进行自定义对话框之前,需要自定义一个对话框布局,就想平常的布局一样:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="match_parent"android:layout_height="match_parent"android:background="#d3d3d3"android:orientation="vertical">
<!--自定义的对话框--><RelativeLayoutandroid:layout_width="match_parent"android:layout_height="wrap_content"><TextViewandroid:id="@+id/dialog_title"android:layout_width="match_parent"android:layout_height="40dp"android:gravity="center_vertical"android:text="这里是显示标题的地方。"android:textSize="18sp"android:textStyle="bold" /><Buttonandroid:id="@+id/dialog_close"android:layout_width="40dp"android:layout_height="40dp"android:layout_alignParentEnd="true"android:background="@mipmap/button_close" /></RelativeLayout><Viewandroid:layout_width="match_parent"android:layout_height="1dp"android:background="#fff"></View><TextViewandroid:id="@+id/dialog_message"android:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_marginLeft="10dp"android:layout_marginTop="20dp"android:text="这里是显示信息的地方。"android:textColor="#000"android:textSize="18sp" /><LinearLayoutandroid:layout_width="match_parent"android:layout_height="wrap_content"android:layout_marginTop="10dp"android:orientation="horizontal"><Buttonandroid:id="@+id/dialog_ok"android:layout_width="0dp"android:layout_height="40dp"android:layout_margin="5dp"android:layout_weight="1"android:background="#000"android:text="ok"android:textColor="#ffffff"android:textSize="16sp"android:textStyle="bold" /><Buttonandroid:id="@+id/dialog_notok"android:layout_width="0dp"android:layout_height="40dp"android:layout_margin="5dp"android:layout_weight="1"android:background="#000"android:text="notok"android:textColor="#ffffff"android:textSize="16sp"android:textStyle="bold" /></LinearLayout>
</LinearLayout>
在activity中,给对话框进行操作:
mDialog = null;mBuilder = new AlertDialog.Builder(Main5Activity.this);//加载布局加载器LayoutInflater inflater = getLayoutInflater();//后面需要用这个view进行find等一系列操作View view_custom = inflater.inflate(R.layout.dialogview, null, false);//加载自定义布局mBuilder.setView(view_custom);//点击非对话框区域对话框不会消失,默认是会消失mBuilder.setCancelable(false);mDialog = mBuilder.create();view_custom.findViewById(R.id.dialog_close).setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {mDialog.dismiss();}});view_custom.findViewById(R.id.dialog_ok).setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {Toast.makeText(Main5Activity.this, "ok", Toast.LENGTH_SHORT).show();mDialog.dismiss();}});view_custom.findViewById(R.id.dialog_notok).setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {Toast.makeText(Main5Activity.this, "not ok", Toast.LENGTH_SHORT).show();mDialog.dismiss();}});TextView title = (TextView) view_custom.findViewById(R.id.dialog_title);TextView message = (TextView) view_custom.findViewById(R.id.dialog_message);title.setText("我是后来加的标题。");message.setText("我是后来加的新信息。");mDialog.show();
over
这只是基本用法。