android DialogFragment简单应用

一个简单的DialogFragment应用 
因为Activity的showDialog(int id)被弃用了,要使用DatePickerDialog,TimePickerDialog,AlterDialog都要继承DialogFragment. 
布局文件就一个Button,就不写出来了. 

MainActivity.java  

 package sky.dialog;

 import android.app.Activity;
 import android.os.Bundle;
 import android.view.View;
 import android.view.View.OnClickListener;
 import android.widget.Button;

 public class MainActivity extends Activity {
     /** Called when the activity is first created. */
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.main);
         Button bt = (Button) findViewById(R.id.showDialog);
         bt.setOnClickListener(new OnClickListener() {

             @Override
             public void onClick(View v) {
                 // TODO Auto-generated method stub
                 showDialog();
             }
         });
     }
     public void showDialog()
     {
         //根据传进的参数来实例化DialogFragment.
         MyDialogFragment newDialog = MyDialogFragment.newInstance(MyDialogFragment.ALTER_DIALOG);
 //      MyDialogFragment newDialog = MyDialogFragment.newInstance(MyDialogFragment.DATE_PICKER_DIALOG);
 //      MyDialogFragment newDialog = MyDialogFragment.newInstance(MyDialogFragment.TIME_PICKER_DiALOG);
         newDialog.show(getFragmentManager(), "alert msg");
     }
 }

MyDialogFragment.java  

 package sky.dialog;

 import android.app.DatePickerDialog;
 import android.app.DatePickerDialog.OnDateSetListener;
 import android.app.AlertDialog;
 import android.app.Dialog;
 import android.app.DialogFragment;
 import android.app.TimePickerDialog;
 import android.app.TimePickerDialog.OnTimeSetListener;
 import android.content.DialogInterface;
 import android.os.Bundle;
 import android.widget.DatePicker;
 import android.widget.TimePicker;

 public class MyDialogFragment extends DialogFragment {
     public static final int DATE_PICKER_DIALOG = 1;
     public static final int ALTER_DIALOG = 2;
     public static final int TIME_PICKER_DiALOG = 3;

     public static MyDialogFragment newInstance(int title) {
         MyDialogFragment myDialogFragment = new MyDialogFragment();
         Bundle bundle = new Bundle();
         bundle.putInt("title", title);
         myDialogFragment.setArguments(bundle);
         return myDialogFragment;
     }

     @Override
     public Dialog onCreateDialog(Bundle savedInstanceState) {
         // TODO Auto-generated method stub
         int args = getArguments().getInt("title");
         //根据传进来的参数选择创建哪种Dialog
         switch (args) {
         case DATE_PICKER_DIALOG:
             return new DatePickerDialog(getActivity(), new OnDateSetListener() {
                 public void onDateSet(DatePicker view, int year, int monthOfYear,
                         int dayOfMonth) {
                     // TODO Auto-generated method stub
                     //月是从0开始的
                     System.out.println( "year-->" + year + "  month-->" + monthOfYear
                             + "  day-->" + dayOfMonth);
                 }
             }, 2012,3, 26);
         case ALTER_DIALOG:
             return new AlertDialog.Builder(getActivity())
                 .setIcon(R.drawable.ic_launcher)
                 .setTitle(getTag())
                 .setPositiveButton("ok",
                         new DialogInterface.OnClickListener() {
                 public void onClick(DialogInterface dialog, int whichButton) {
                     //点击ok触发的事件
                     System.out.println("click ok!");
                 }
                 })
             .setNegativeButton("cancle",
                     new DialogInterface.OnClickListener() {
                 public void onClick(DialogInterface dialog, int whichButton) {
                     //点击cancle触发的时间
                     System.out.println("click cancle");
                 }
                 })
                 .create();
         case TIME_PICKER_DiALOG:
             return new TimePickerDialog(getActivity(),new OnTimeSetListener() {

                 public void onTimeSet(TimePicker view, int hourOfDay, int minute) {
                     // TODO Auto-generated method stub
                     System.out.println("hour-->"+hourOfDay+"  minute-->"+ minute);
                 }
             }, 13, 23, true);
         }
         return null;
     }

 }

=========================================================================================================================

可创建的另一种碎片类型是对话框碎片。一个对话框碎片浮动在活动上方，并且以模态方式显示。当需要获得用户的响应，然后才能继续执行操作的时候，对话框碎片十分有用。为了创建一个对话框碎片，需要扩展DialogFragment基类。

下面的“试一试”展示了创建对话框碎片的方法。

试一试 创建并使用一个对话碎片

DialogFragmentExample.zip代码文件可以在Wrox.com上下载

(1) 使用Eclipse创建一个Android项目，并把它命名为DialogFragmentExample。

(2) 向包里添加一个Java类文件并将其命名为Fragment1。

(3) 使用如下代码填充Fragment1.java文件。
package net.learn2develop.DialogFragmentExample;

import android.app.AlertDialog;
import android.app.Dialog;
import android.app.DialogFragment;
import android.content.DialogInterface;
import android.os.Bundle;

public class Fragment1 extends DialogFragment {

     static Fragment1 newInstance(String title) {
          Fragment1 fragment = new Fragment1();
          Bundle args = new Bundle();
          args.putString("title", title);
          fragment.setArguments(args);
          return fragment;
     }

     @Override
     public Dialog onCreateDialog(Bundle savedInstanceState) {
          String title = getArguments().getString("title");
          return new AlertDialog.Builder(getActivity())
          .setIcon(R.drawable.ic_launcher)
          .setTitle(title)
          .setPositiveButton("OK",
                    new DialogInterface.OnClickListener() {
               public void onClick(DialogInterface dialog,
int whichButton) {
                    ((DialogFragmentExampleActivity)
                              getActivity()).doPositiveClick();
               }
          })
          .setNegativeButton("Cancel",
                    new DialogInterface.OnClickListener() {
               public void onClick(DialogInterface dialog,
                         int whichButton) {
                    ((DialogFragmentExampleActivity)
                              getActivity()).doNegativeClick();
               }
        }).create();
     }       

}

(4) 使用下列粗体显示的代码填充DialogFragmentExampleActivity.java文件。
package net.learn2develop.DialogFragmentExample;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;

public class DialogFragmentExampleActivity extends Activity {
     /** Called when the activity is first created. */
     @Override
     public void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.main);
       
          Fragment1 dialogFragment = Fragment1.newInstance(
                    "Are you sure you want to do this?");
               dialogFragment.show(getFragmentManager(), "dialog");  
     }
   
     public void doPositiveClick() {
          //---perform steps when user clicks on OK---
          Log.d("DialogFragmentExample", "User clicks on OK");
     }

     public void doNegativeClick() {
          //---perform steps when user clicks on Cancel---
          Log.d("DialogFragmentExample", "User clicks on Cancel");
     }

}

(5) 按F11键在Android模拟器上调试应用程序。图4-26所示的碎片在一个警告对话框中显示。单击OK按钮或Cancel按钮，观察显示的消息。

示例说明

为创建一个对话碎片，首先Java类要扩展DialogFragment基类：

public class Fragment1 extends DialogFragment{
}

在本例中，创建了一个警告对话框，这是一个显示一条消息及可选按钮的对话框窗口。在Fragment1类中，定义了newInstance()方法：
    static Fragment1 newInstance(String title) {
         Fragment1 fragment = new Fragment1();
         Bundle args = new Bundle();
         args.putString("title", title);
         fragment.setArguments(args);
         return fragment;
    }

newInstance()方法允许创建碎片的一个新实例，同时它接受一个指定警告对话框中要显示的字符串(title)的参数。title随后存储在一个Bundle对象里供之后使用。

接下来定义了onCreateDialog()方法，该方法在onCreate()之后、onCreateView()之前调用：
@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
     String title = getArguments().getString("title");
        return new AlertDialog.Builder(getActivity())
        .setIcon(R.drawable.ic_launcher)
        .setTitle(title)
        .setPositiveButton("OK",
                  new DialogInterface.OnClickListener() {
             public void onClick(DialogInterface dialog,
                       int whichButton) {
                  ((DialogFragmentExampleActivity)
                            getActivity()).doPositiveClick();
             }
        })
        .setNegativeButton("Cancel",
new DialogInterface.OnClickListener() {
             public void onClick(DialogInterface dialog,
int whichButton) {
                  ((DialogFragmentExampleActivity)
getActivity()).doNegativeClick();
             }
        }).create();
   }     

在这里，创建的警告对话框有两个按钮：OK和Cancel。要在该对话框中显示的字符串从保存在Bundle对象中的title参数中获取。

为了显示对话框碎片，创建它的一个实例并调用它的show()方法：
    Fragment1 dialogFragment = Fragment1.newInstance(
               "Are you sure you want to do this?");
          dialogFragment.show(getFragmentManager(), "dialog"); 
 
还需要实现两种方法：doPostiveClick()和doNegativeClick()，分别用于处理用户单击OK按钮或Cancel按钮的情况。
     public void doPositiveClick() {
          //---perform steps when user clicks on OK---
          Log.d("DialogFragmentExample", "User clicks on OK");
     }

     public void doNegativeClick() {
          //---perform steps when user clicks on Cancel---
          Log.d("DialogFragmentExample", "User clicks on Cancel");
}