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      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.text.Editable;
     26 import android.os.Bundle;
     27 import android.view.View;
     28 import android.view.View.OnClickListener;
     29 import android.widget.Button;
     30 import android.widget.TextView;
     31 
     32 /**
     33  * Shows how an activity can send data to its launching activity when done.y.
     34  * <p>This can be used, for example, to implement a dialog alowing the user to
     35 pick an e-mail address or image -- the picking activity sends the selected
     36 data back to the originating activity when done.</p>
     37 
     38 <p>The example here is composed of two activities: ReceiveResult launches
     39 the picking activity and receives its results; SendResult allows the user
     40 to pick something and sends the selection back to its caller.  Implementing
     41 this functionality involves the
     42 {@link android.app.Activity#setResult setResult()} method for sending a
     43 result and
     44 {@link android.app.Activity#onActivityResult onActivityResult()} to
     45 receive it.</p>
     46 
     47 <h4>Demo</h4>
     48 App/Activity/Receive Result
     49 
     50 <h4>Source files</h4>
     51 <table class="LinkTable">
     52         <tr>
     53             <td class="LinkColumn">src/com.example.android.apis/app/ReceiveResult.java</td>
     54             <td class="DescrColumn">Launches pick activity and receives its result</td>
     55         </tr>
     56         <tr>
     57             <td class="LinkColumn">src/com.example.android.apis/app/SendResult.java</td>
     58             <td class="DescrColumn">Allows user to pick an option and sends it back to its caller</td>
     59         </tr>
     60         <tr>
     61             <td class="LinkColumn">/res/any/layout/receive_result.xml</td>
     62             <td class="DescrColumn">Defines contents of the ReceiveResult screen</td>
     63         </tr>
     64         <tr>
     65             <td class="LinkColumn">/res/any/layout/send_result.xml</td>
     66             <td class="DescrColumn">Defines contents of the SendResult screen</td>
     67         </tr>
     68 </table>
     69 
     70  */
     71 public class ReceiveResult extends Activity {
     72     /**
     73      * Initialization of the Activity after it is first created.  Must at least
     74      * call {@link android.app.Activity#setContentView setContentView()} to
     75      * describe what is to be displayed in the screen.
     76      */
     77     @Override
     78 	protected void onCreate(Bundle savedInstanceState) {
     79         // Be sure to call the super class.
     80         super.onCreate(savedInstanceState);
     81 
     82         // See assets/res/any/layout/hello_world.xml for this
     83         // view layout definition, which is being set here as
     84         // the content of our screen.
     85         setContentView(R.layout.receive_result);
     86 
     87         // Retrieve the TextView widget that will display results.
     88         mResults = (TextView)findViewById(R.id.results);
     89 
     90         // This allows us to later extend the text buffer.
     91         mResults.setText(mResults.getText(), TextView.BufferType.EDITABLE);
     92 
     93         // Watch for button clicks.
     94         Button getButton = (Button)findViewById(R.id.get);
     95         getButton.setOnClickListener(mGetListener);
     96     }
     97 
     98     /**
     99      * This method is called when the sending activity has finished, with the
    100      * result it supplied.
    101      *
    102      * @param requestCode The original request code as given to
    103      *                    startActivity().
    104      * @param resultCode From sending activity as per setResult().
    105      * @param data From sending activity as per setResult().
    106      */
    107     @Override
    108 	protected void onActivityResult(int requestCode, int resultCode,
    109 		Intent data) {
    110         // You can use the requestCode to select between multiple child
    111         // activities you may have started.  Here there is only one thing
    112         // we launch.
    113         if (requestCode == GET_CODE) {
    114 
    115             // We will be adding to our text.
    116             Editable text = (Editable)mResults.getText();
    117 
    118             // This is a standard resultCode that is sent back if the
    119             // activity doesn't supply an explicit result.  It will also
    120             // be returned if the activity failed to launch.
    121             if (resultCode == RESULT_CANCELED) {
    122                 text.append("(cancelled)");
    123 
    124             // Our protocol with the sending activity is that it will send
    125             // text in 'data' as its result.
    126             } else {
    127                 text.append("(okay ");
    128                 text.append(Integer.toString(resultCode));
    129                 text.append(") ");
    130                 if (data != null) {
    131                     text.append(data.getAction());
    132                 }
    133             }
    134 
    135             text.append("\n");
    136         }
    137     }
    138 
    139     // Definition of the one requestCode we use for receiving resuls.
    140     static final private int GET_CODE = 0;
    141 
    142     private OnClickListener mGetListener = new OnClickListener() {
    143         public void onClick(View v) {
    144             // Start the activity whose result we want to retrieve.  The
    145             // result will come back with request code GET_CODE.
    146             Intent intent = new Intent(ReceiveResult.this, SendResult.class);
    147             startActivityForResult(intent, GET_CODE);
    148         }
    149     };
    150 
    151     private TextView mResults;
    152 }
    153 
    154