1 /*
2  * Copyright (C) 2007 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.example.android.apis.app;
18 
19 // Need the following import to get access to the app resources, since this
20 // class is in a sub-package.
21 import com.example.android.apis.R;
22 
23 import android.app.Activity;
24 import android.content.Intent;
25 import android.os.Bundle;
26 import android.view.View;
27 import android.view.View.OnClickListener;
28 import android.widget.Button;
29 
30 
31 /**
32  * <p>Example of removing yourself from the history stack after forwarding to
33  * another activity. This can be useful, for example, to implement
34     a confirmation dialog before the user goes on to another activity -- once the
35     user has confirmed this operation, they should not see the dialog again if they
36 go back from it.</p>
37 
38 <p>Note that another way to implement a confirmation dialog would be as
39 an activity that returns a result to its caller.  Either approach can be
40 useful depending on how it makes sense to structure the application.</p>
41 
42 <h4>Demo</h4>
43 App/Activity/Receive Result
44 
45 <h4>Source files</h4>
46 <table class="LinkTable">
47         <tr>
48             <td class="LinkColumn">src/com.example.android.apis/app/Forwarding.java</td>
49             <td class="DescrColumn">Forwards the user to another activity when its button is pressed</td>
50         </tr>
51         <tr>
52             <td class="LinkColumn">/res/any/layout/forwarding.xml</td>
53             <td class="DescrColumn">Defines contents of the Forwarding screen</td>
54         </tr>
55 </table>
56  */
57 public class Forwarding extends Activity
58 {
59     @Override
onCreate(Bundle savedInstanceState)60 	protected void onCreate(Bundle savedInstanceState)
61     {
62         super.onCreate(savedInstanceState);
63 
64         setContentView(R.layout.forwarding);
65 
66         // Watch for button clicks.
67         Button goButton = (Button)findViewById(R.id.go);
68         goButton.setOnClickListener(mGoListener);
69     }
70 
71     private OnClickListener mGoListener = new OnClickListener()
72     {
73         public void onClick(View v)
74         {
75             // Here we start the next activity, and then call finish()
76             // so that our own will stop running and be removed from the
77             // history stack.
78             Intent intent = new Intent();
79             intent.setClass(Forwarding.this, ForwardTarget.class);
80             startActivity(intent);
81             finish();
82         }
83     };
84 }
85 
86