Moderator, Bürokraten, Checkuser-Berechtigte, developer, emailconfirmed, Oberflächenadministratoren, Oversighter, Administratoren
11.008
Bearbeitungen
Android Training/Starting Another Activity: Unterschied zwischen den Versionen
Android Training/Starting Another Activity (bearbeiten)
Version vom 20. Dezember 2015, 21:27 Uhr
, 20. Dezember 2015Leerzeichen hinzugefüg
(Diese Seite wurde zum Übersetzen freigegeben) |
(Leerzeichen hinzugefüg) |
||
| Zeile 2: | Zeile 2: | ||
<translate> | <translate> | ||
<!--T:1--> | <!--T:1--> | ||
After completing the [[Spezial:MyLanguage/Android Training/Building a Simple User Interface|previous lesson]], you have an app that shows an activity (a single screen) with a text field and a button. In this lesson, you’ll add some code to<code>MyActivity</code> that starts a new activity when the user clicks the Send button. | After completing the [[Spezial:MyLanguage/Android Training/Building a Simple User Interface|previous lesson]], you have an app that shows an activity (a single screen) with a text field and a button. In this lesson, you’ll add some code to <code>MyActivity</code> that starts a new activity when the user clicks the Send button. | ||
== Respond to the Send Button == <!--T:2--> | == Respond to the Send Button == <!--T:2--> | ||
# In Android Studio, from the <code>res/layout</code> directory, edit the<code>content_my.xml</code> file. | # In Android Studio, from the <code>res/layout</code> directory, edit the <code>content_my.xml</code> file. | ||
# Add the <code>[http://developer.android.com/reference/android/view/View.html#attr_android:onClick android:onClick]</code> attribute to the <code>[http://developer.android.com/reference/android/widget/Button.html <Button>]</code> element.</translate> | # Add the <code>[http://developer.android.com/reference/android/view/View.html#attr_android:onClick android:onClick]</code> attribute to the <code>[http://developer.android.com/reference/android/widget/Button.html <Button>]</code> element.</translate> | ||
#: ''res/layout/content_my.xml''<syntaxhighlight lang="java"> | #: ''res/layout/content_my.xml''<syntaxhighlight lang="java"> | ||
| Zeile 32: | Zeile 32: | ||
== Build an Intent == <!--T:5--> | == Build an Intent == <!--T:5--> | ||
# In <code>MyActivity.java</code>, inside the <code>sendMessage()</code> method, create an <code>Intent</code> to start an activity called<code>DisplayMessageActivity</code> with the following code:</translate> | # In <code>MyActivity.java</code>, inside the <code>sendMessage()</code> method, create an <code>Intent</code> to start an activity called <code>DisplayMessageActivity</code> with the following code:</translate> | ||
#: ''java/com.mycompany.myfirstapp/MyActivity.java''<syntaxhighlight lang="java"> | #: ''java/com.mycompany.myfirstapp/MyActivity.java''<syntaxhighlight lang="java"> | ||
public void sendMessage(View view) { | public void sendMessage(View view) { | ||
| Zeile 77: | Zeile 77: | ||
#: <translate><!--T:10--> | #: <translate><!--T:10--> | ||
For the next activity to query the extra data, you should define the key for your intent's extra using a public constant. It's generally a good practice to define keys for intent extras using your app's package name as a prefix. This ensures the keys are unique, in case your app interacts with other apps. | For the next activity to query the extra data, you should define the key for your intent's extra using a public constant. It's generally a good practice to define keys for intent extras using your app's package name as a prefix. This ensures the keys are unique, in case your app interacts with other apps. | ||
# In the <code>sendMessage()</code> method, to finish the intent, call the <code>startActivity()</code> method, passing it the<code>Intent</code> object created in step 1. | # In the <code>sendMessage()</code> method, to finish the intent, call the <code>startActivity()</code> method, passing it the <code>Intent</code> object created in step 1. | ||
<!--T:11--> | <!--T:11--> | ||
| Zeile 157: | Zeile 157: | ||
</syntaxhighlight> | </syntaxhighlight> | ||
#: <translate><!--T:16--> | #: <translate><!--T:16--> | ||
'''Note:''' If you are using an IDE other than Android Studio, your project does not contain the<code>activity_display_message</code> layout that's requested by <code>[http://developer.android.com/reference/android/app/Activity.html#setContentView(android.view.View) setContentView()]</code>. That's OK because you will update this method later and won't be using that layout. | '''Note:''' If you are using an IDE other than Android Studio, your project does not contain the <code>activity_display_message</code> layout that's requested by <code>[http://developer.android.com/reference/android/app/Activity.html#setContentView(android.view.View) setContentView()]</code>. That's OK because you will update this method later and won't be using that layout. | ||
# To your <code>strings.xml</code> file, add the new activity's title as follows:</translate> | # To your <code>strings.xml</code> file, add the new activity's title as follows:</translate> | ||
#: <syntaxhighlight lang="xml"> | #: <syntaxhighlight lang="xml"> | ||