/* * Copyright (C) 2007 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.example.android.apis.app; // Need the following import to get access to the app resources, since this // class is in a sub-package. import com.example.android.apis.R; import android.app.Activity; import android.content.Intent; import android.text.Editable; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.TextView; /** * Shows how an activity can send data to its launching activity when done.y. *

This can be used, for example, to implement a dialog alowing the user to pick an e-mail address or image -- the picking activity sends the selected data back to the originating activity when done.

The example here is composed of two activities: ReceiveResult launches the picking activity and receives its results; SendResult allows the user to pick something and sends the selection back to its caller. Implementing this functionality involves the {@link android.app.Activity#setResult setResult()} method for sending a result and {@link android.app.Activity#onActivityResult onActivityResult()} to receive it.

Demo

App/Activity/Receive Result

Source files

src/com.example.android.apis/app/ReceiveResult.java Launches pick activity and receives its result
src/com.example.android.apis/app/SendResult.java Allows user to pick an option and sends it back to its caller
/res/any/layout/receive_result.xml Defines contents of the ReceiveResult screen
/res/any/layout/send_result.xml Defines contents of the SendResult screen
*/ public class ReceiveResult extends Activity { /** * Initialization of the Activity after it is first created. Must at least * call {@link android.app.Activity#setContentView setContentView()} to * describe what is to be displayed in the screen. */ @Override protected void onCreate(Bundle savedInstanceState) { // Be sure to call the super class. super.onCreate(savedInstanceState); // See assets/res/any/layout/hello_world.xml for this // view layout definition, which is being set here as // the content of our screen. setContentView(R.layout.receive_result); // Retrieve the TextView widget that will display results. mResults = (TextView)findViewById(R.id.results); // This allows us to later extend the text buffer. mResults.setText(mResults.getText(), TextView.BufferType.EDITABLE); // Watch for button clicks. Button getButton = (Button)findViewById(R.id.get); getButton.setOnClickListener(mGetListener); } /** * This method is called when the sending activity has finished, with the * result it supplied. * * @param requestCode The original request code as given to * startActivity(). * @param resultCode From sending activity as per setResult(). * @param data From sending activity as per setResult(). */ @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) { // You can use the requestCode to select between multiple child // activities you may have started. Here there is only one thing // we launch. if (requestCode == GET_CODE) { // We will be adding to our text. Editable text = (Editable)mResults.getText(); // This is a standard resultCode that is sent back if the // activity doesn't supply an explicit result. It will also // be returned if the activity failed to launch. if (resultCode == RESULT_CANCELED) { text.append("(cancelled)"); // Our protocol with the sending activity is that it will send // text in 'data' as its result. } else { text.append("(okay "); text.append(Integer.toString(resultCode)); text.append(") "); if (data != null) { text.append(data.getAction()); } } text.append("\n"); } } // Definition of the one requestCode we use for receiving resuls. static final private int GET_CODE = 0; private OnClickListener mGetListener = new OnClickListener() { public void onClick(View v) { // Start the activity whose result we want to retrieve. The // result will come back with request code GET_CODE. Intent intent = new Intent(ReceiveResult.this, SendResult.class); startActivityForResult(intent, GET_CODE); } }; private TextView mResults; }