android 弹出对话框之 AlertDialog

1.在测试时,如何实现一个提示

可以使用

Toast.makeText(this, "这是一个提示", Toast.LENGTH_SHORT).show(); 
 //从资源文件string.xml 里面取提示信息
   Toast.makeText(this, getString(R.string.welcome), Toast.LENGTH_SHORT).show();
 这个提示会几秒钟后消失

2.可以使用AlertDialog.Builder 才产生一个提示框.

new AlertDialog.Builder(this)
     .setTitle("Android 提示")
     .setMessage("这是一个提示,请确定")
     .show();
 带一个确定的对话框new AlertDialog.Builder(this)
          .setMessage("这是第二个提示")
          .setPositiveButton("确定",
                          new DialogInterface.OnClickListener(){
                                  public void onClick(DialogInterface dialoginterface, int i){
                                      //按钮事件
                                  }
                          })
         AlertDialog.Builder 还有很多复杂的用法,有确定和取消的对话框
new AlertDialog.Builder(this)
         .setTitle("提示")
         .setMessage("确定退出?")
         .setIcon(R.drawable.quit)
         .setPositiveButton("确定", new DialogInterface.OnClickListener() {
         public void onClick(DialogInterface dialog, int whichButton) {
         setResult(RESULT_OK);//确定按钮事件
         finish();
         }
         })
         .setNegativeButton("取消", new DialogInterface.OnClickListener() {
         public void onClick(DialogInterface dialog, int whichButton) {
          //取消按钮事件
         }
         })
        
实例代码如下
public class AlertDialogBuilderSample extends Activity {
  View myView;
  EditText passWord, userName;@Override
  public void onCreate(Bundle icicle) {
   super.onCreate(icicle);
   setContentView(R.layout.test); LayoutInflater factory = LayoutInflater.from(this);
   myView = factory.inflate(R.layout.userinfo, null);// 获取布局文件；
   passWord = (EditText) myView.findViewById(R.id.password);
   // 获取自定义布局文件中的用户名编辑框组件
   userName = (EditText) myView.findViewById(R.id.usernameEdit);
   // 获取自定义文件中的密码编辑框组件 final Button btnQuit = (Button) findViewById(R.id.button1);
   btnQuit.setOnClickListener(new Button.OnClickListener() {
    public void onClick(View v) {
     new AlertDialog.Builder(AlertDialogBuilderSample.this).setView(
       myView).setTitle("Question").setMessage(
       "自定义弹出框例子").setIcon(
       R.drawable.icon).setPositiveButton("Yes",
       new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog,
          int whichButton) {
         setResult(RESULT_OK);
         finish();
        }
       }).setNegativeButton("No",
       new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog,
          int whichButton) {
         Log.v("tag","pws"+passWord.getText());
         Log.v("tag","name"+userName.getText());
        }
       }).show();
    }
   });
   final Button btnTravels = (Button) findViewById(R.id.button2);
   btnTravels.setOnClickListener(new Button.OnClickListener() {
    public void onClick(View v) {
     new AlertDialog.Builder(AlertDialogBuilderSample.this)
       .setTitle("I want to go to").setItems(
         R.array.items_indide_dialog,
         new DialogInterface.OnClickListener() {
          public void onClick(DialogInterface dialog,
            int whichcountry) {
           String[] travelcountries = getResources()
             .getStringArray(
               R.array.items_indide_dialog);
           new AlertDialog.Builder(
             AlertDialogBuilderSample.this)
             .setMessage(
               "I’m going to "
                 + travelcountries[whichcountry])
             .setNeutralButton(
               "Cancel",
               new DialogInterface.OnClickListener() {
                public void onClick(
                  DialogInterface dialog,
                  int whichButton) {
                }
               }).show();
          }
         }).show();
    }
   });
  }
 }
 userinfo.xml<?xml version="1.0" encoding="UTF-8"?>
 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  >
  <LinearLayout
      android:id="@+id/usernamelayout"
      android:layout_width="fill_parent"
      android:layout_height="wrap_content"
   android:orientation="horizontal"
   android:layout_marginTop="10dip">
   <TextView
       android:id="@+id/usernameText"
       android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:gravity="center"
    android:layout_centerInParent="true"
    android:layout_weight="3"
    android:text="用户名"/>
   <EditText
       android:id="@+id/usernameEdit"
       android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:layout_weight="1"
    android:maxLength="20"/>
  </LinearLayout>
  
  <!-- 地区 -->
  <LinearLayout
      android:id="@+id/arealayout"
      android:layout_width="fill_parent"
      android:layout_height="wrap_content"
   android:orientation="horizontal"
   android:layout_below="@+id/usernamelayout">
   <TextView
       android:id="@+id/passwordTitle"
       android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:gravity="center"
    android:layout_centerInParent="true"
    android:layout_weight="3"
    android:text="密码"/>
   <EditText
       android:id="@+id/password"
       android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:layout_weight="1"
    android:maxLength="20"/>
  </LinearLayout>
 </RelativeLayout>