android_learning:headfirst_android_development_notes:chapter_13
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Table of Contents
Chapter 13
Under development.
p. 544
The File > New > Service menu has changed in Android Studio 1.5.1. Now there are explicit entries for the two Intent classes.
p. 547: Code block
- DelayedMessageService.java
package com.hfad.joke; import android.app.IntentService; import android.content.Intent; import android.util.Log; public class DelayedMessageService extends IntentService { public static final String EXTRA_MESSAGE = "message"; public DelayedMessageService() { super("DelayedMessageService"); } @Override protected void onHandleIntent(Intent intent) { synchronized (this) { try { wait(10000); } catch (InterruptedException e) { e.printStackTrace(); } } String text = intent.getStringExtra(EXTRA_MESSAGE); showText(text); } private void showText(final String text) { Log.v("DelayedMessageService", "The message is: " + text); } }
p. 550: Code block
public void onClick(View view) { Intent intent = new Intent(this, DelayedMessageService.class); intent.putExtra(DelayedMessageService.EXTRA_MESSAGE, getResources().getString(R.string.button_response)); startService(intent); }
p. 553
In other words, while most Intent methods run off the main thread, but onStartCommand() runs on the main thread.
p. 554
- DelayedMessageService.java
package com.hfad.joke; import android.app.IntentService; import android.content.Intent; import android.os.Handler; import android.widget.Toast; public class DelayedMessageService extends IntentService { public static final String EXTRA_MESSAGE = "message"; private Handler handler; public DelayedMessageService() { super("DelayedMessageService"); } @Override public int onStartCommand(Intent intent, int flags, int startId) { // This method runs on the main thread, so the Handler that's // instantiated here will also be running on the main thread. handler = new Handler(); return super.onStartCommand(intent, flags, startId); } @Override protected void onHandleIntent(Intent intent) { synchronized (this) { try { wait(10000); } catch (InterruptedException e) { e.printStackTrace(); } } String text = intent.getStringExtra(EXTRA_MESSAGE); showText(text); } private void showText(final String text) { handler.post(new Runnable() { @Override public void run() { Toast.makeText(getApplicationContext(), text, Toast.LENGTH_LONG).show(); } }); } }
android_learning/headfirst_android_development_notes/chapter_13.1461973596.txt.gz · Last modified: 2016/04/29 23:46 (external edit)