Wikizone - Benutzerbeiträge [de]

Android - Cheat Sheet

2013-10-10T14:52:12Z

79.240.23.31: /* Buttons verdrahten */

Hier gibt es nur Code Schnipsel zum Kopieren ohne Erklärung
== Neue Activity ==
MyNameActivity.java // Class
activity_my_name.xml // Layout File
AndroidManifest.xml
strings.xml

=== Activity Class ===

<pre>
package de.webmynet.android.myappname;

import android.app.Activity;
import android.os.Bundle;

public class MyNameActivity extends Activity{

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_my_name);
}
}
</pre>

== Buttons verdrahten ==
<pre>
import android.widget.Button;
public class MyNameActivity extends Activity implements OnClickListener {
Button b1,b2;
...
b1 = (Button)findViewById(R.id.b1);
b2 = (Button)findViewById(R.id.b2);
b1.setOnClickListener(this);
b2.setOnClickListener(this);
...
@Override
public void onClick(View v) {
int id = v.getId();
Intent i = null;
switch (id){
case R.id.b1:
i = new Intent(this,OtherNameActivity.class);
break;
case R.id.b2:
i = new Intent("de.webmynet.appname.OTHERNAME");//Variant with Manifest Activity Name
break;

default:
break;
}
startActivity(i);
}
</pre>

Android - Cheat Sheet

2013-10-10T14:47:53Z

79.240.23.31: /* Layout Buttons verdrahten */

Hier gibt es nur Code Schnipsel zum Kopieren ohne Erklärung
== Neue Activity ==
MyNameActivity.java // Class
activity_my_name.xml // Layout File
AndroidManifest.xml
strings.xml

=== Activity Class ===

<pre>
package de.webmynet.android.myappname;

import android.app.Activity;
import android.os.Bundle;

public class MyNameActivity extends Activity{

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_my_name);
}
}
</pre>

== Buttons verdrahten ==
<pre>
import android.widget.Button;
public class MyNameActivity extends Activity implements OnClickListener {
Button b1,b2;
...
b1 = (Button)findViewById(R.id.b1);
b2 = (Button)findViewById(R.id.b2);
b1.setOnClickListener(this);
b2.setOnClickListener(this);
...
@Override
public void onClick(View v) {
int id = v.getId();
Intent i = null;
switch (id){
case R.id.b1:
i = new Intent(this,SendActivity.class);
break;
case R.id.b2:
i = new Intent(this,SettingsActivity.class);
break;

default:
break;
}
startActivity(i);
}
</pre>

Android - Cheat Sheet

2013-10-10T14:40:01Z

79.240.23.31: /* Neue Activity */

Hier gibt es nur Code Schnipsel zum Kopieren ohne Erklärung
== Neue Activity ==
MyNameActivity.java // Class
activity_my_name.xml // Layout File
AndroidManifest.xml
strings.xml

=== Activity Class ===

<pre>
package de.webmynet.android.myappname;

import android.app.Activity;
import android.os.Bundle;

public class MyNameActivity extends Activity{

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_my_name);
}
}
</pre>

== Layout Buttons verdrahten ==
<pre>
import android.widget.Button;
...
Button b1,b2;
...
b1 = (Button)findViewById(R.id.b1);
b2 = (Button)findViewById(R.id.b2);
b1.setOnClickListener(this);
b2.setOnClickListener(this);
...
@Override
public void onClick(View v) {
int id = v.getId();
Intent i = null;
switch (id){
case R.id.b1:
i = new Intent(this,SendActivity.class);
break;
case R.id.b2:
i = new Intent(this,SettingsActivity.class);
break;

default:
break;
}
startActivity(i);
}
</pre>

Android Location API - Simple Location

2013-10-10T14:33:30Z

79.240.23.31: /* Kompletter Code */

== Einleitung ==

== Projekt ==
1. Android Projekt erstellen Name: Simple Location
== Permissions ==
Zum manifest.xml hinzufügen:
* INTERNET
* ACCESS_FINE_LOCATION
* ACCESS_COARSE_LOCATION

<pre>
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
</pre>

== Layout ==
<pre>
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >

<LinearLayout
android:id="@+id/linearLayout1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="40dip"
android:orientation="horizontal" >

<TextView
android:id="@+id/TextView01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dip"
android:layout_marginRight="5dip"
android:text="Latitude: "
android:textSize="20dip" >
</TextView>

<TextView
android:id="@+id/TextView02"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="unknown"
android:textSize="20dip" >
</TextView>
</LinearLayout>

<LinearLayout
android:id="@+id/linearLayout2"
android:layout_width="match_parent"
android:layout_height="wrap_content" >

<TextView
android:id="@+id/TextView03"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dip"
android:layout_marginRight="5dip"
android:text="Longitute: "
android:textSize="20dip" >
</TextView>

<TextView
android:id="@+id/TextView04"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="unknown"
android:textSize="20dip" >
</TextView>
</LinearLayout>

</LinearLayout>
</pre>

== ShowLocation Activity programmieren ==
1. Einen LocationListener implementieren
import android.location.LocationListener;
...
public class ShowLocationActivity extends Activity''' implements LocationListener''' {
...
Eclipse zeigt daß wir für das Interface diverse Funktionen brauchen:

<pre>
@Override
public void onLocationChanged(Location arg0) {
// TODO Auto-generated method stub

}

@Override
public void onProviderDisabled(String arg0) {
// TODO Auto-generated method stub

}

@Override
public void onProviderEnabled(String arg0) {
// TODO Auto-generated method stub

}

@Override
public void onStatusChanged(String arg0, int arg1, Bundle arg2) {
// TODO Auto-generated method stub

}

</pre>

Dann verdrahten wir die Textfelder des Layouts mit dem Code...
<pre>
public class ShowLocationActivity extends Activity implements LocationListener{
private TextView latitudeField;
private TextView longitudeField;
private LocationManager locationManager;
private String provider;
...

// activity is created...
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_show_location);
latitudeField = (TextView) findViewById(R.id.TextView02);
longitudeField = (TextView) findViewById(R.id.TextView04);
...
</pre>

bei den Textviews haben wir auch schon einen LocationManager definiert und einen String, der den gewählten Provider speichern wird (gps oder network). Auch dieser wird in onCreate instanziiert:

LocationManager Service holen
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
Ein Criteria Objekt erstellen daß unsere Bedingungen an den Service enthält. Da wir nichts setzen sind es hier Standardbedingungen.
Criteria criteria = new Criteria();
Wir Fragen den Location Manager welches der beste Provider für unsere Kriterien sind (false -> auch wenn diese abgeschaltet sind).
provider = locationManager.getBestProvider(criteria, false);
Welches war die letzte bekannte Position ? Diese wir in ein Location Objekt gespeichert.
Location location = locationManager.getLastKnownLocation(provider);
Wenn wir was haben schreiben wir es in die Textfelder.
<pre>
if(location != null){
System.out.println("Provider " + provider + "has been selected.");
onLocationChanged(location);
}else{
tvLatitude.setText("Location is not available");
tvLongitude.setText("Location is not available");
}
</pre>

Wenn die Activity startet (oder resumed wird) soll der LocationManager regelmäßig Updates über den gewählten provider liefern. Es sollen aber mindestens 600ms und 10m zwischen den Updates liegen. Damit wir dann auch etwas übernehmen können wird im letzten Parameter ein locationManager übergeben dessen onLocationChanged Methode aufgerufen werden soll. In diesem Fall übergeben wir ihn sich selbst.
<pre>
/* Request updates at startup */
@Override
protected void onResume() {
super.onResume();
locationManager.requestLocationUpdates(provider, 600, 10, this);
}
</pre>

Wenn die Activity pausiert sollen auch die Updates pausieren
<pre>
/* locationlistener updates stoppen wenn Activity pausiert sonst gibt es Fehler im Log */
@Override
protected void onPause() {
super.onPause();
locationManager.removeUpdates(this);
}
</pre>

Wenn eine neue Position kommt -> Felder updaten:
<pre>
@Override
public void onLocationChanged(Location location) {
int lat = (int) (location.getLatitude());
int lng = (int) (location.getLongitude());
tvLatitude.setText(String.valueOf(lat));
tvLongitude.setText(String.valueOf(lng));
}
</pre>

== Kompletter Code ==
=== Layout ===
<pre>
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >

<LinearLayout
android:id="@+id/linearLayout1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="40dip"
android:orientation="horizontal" >

<TextView
android:id="@+id/TextView01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dip"
android:layout_marginRight="5dip"
android:text="@string/latitude"
android:textSize="20sp" >
</TextView>

<TextView
android:id="@+id/TextView02"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/unknown"
android:textSize="20sp" >
</TextView>
</LinearLayout>

<LinearLayout
android:id="@+id/linearLayout2"
android:layout_width="match_parent"
android:layout_height="wrap_content" >

<TextView
android:id="@+id/TextView03"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dip"
android:layout_marginRight="5dip"
android:text="@string/longitude"
android:textSize="20sp" >
</TextView>

<TextView
android:id="@+id/TextView04"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/unknown"
android:textSize="20sp" >
</TextView>
</LinearLayout>

</LinearLayout>
</pre>

=== SimpleLocation.java ===

Hier die komplette Activity
<pre>
package de.webmynet.android.simplelocation;

//import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
//import android.view.Menu;
import android.widget.TextView;
import android.widget.Toast;

public class ShowLocationActivity extends Activity implements LocationListener{
private TextView tvLatitude;
private TextView tvLongitude;
private LocationManager locationManager;
private String provider;

// activity is created...
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_show_location);

// Text Views abrufen
tvLatitude = (TextView) findViewById(R.id.TextView02);
tvLongitude = (TextView) findViewById(R.id.TextView04);
// LocationManager Service Handle holen
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
// Criteria Objekt für Providerauswahl
//Criteria criteria = new Criteria();
//criteria.setAccuracy(2);
//provider = locationManager.getBestProvider(criteria, false);
provider = "gps";
Location location = locationManager.getLastKnownLocation(provider);
//Location TVs setzen
if(location != null){
System.out.println("Provider " + provider + "has been selected.");
onLocationChanged(location);
}else{
tvLatitude.setText("Location is not available");
tvLongitude.setText("Location is not available");
}

}
/* Location updates liefern wenn die Activity (neu-)startet */
@Override
protected void onResume() {
super.onResume();
Toast.makeText(this, "Selected provider: " + provider, Toast.LENGTH_SHORT).show();
locationManager.requestLocationUpdates(provider, 600, 20, this);
}

/* locationlistener updates stoppen wenn Activity pausiert sonst gibt es Fehler im Log */
@Override
protected void onPause() {
super.onPause();
locationManager.removeUpdates(this);
}

@Override
public void onLocationChanged(Location location) {
float lat = (float) (location.getLatitude());
float lng = (float) (location.getLongitude());
tvLatitude.setText(String.valueOf(lat));
tvLongitude.setText(String.valueOf(lng));
}

@Override
public void onProviderDisabled(String provider) {
Toast.makeText(this, "Provider disabled: " + provider, Toast.LENGTH_SHORT).show();
}

@Override
public void onProviderEnabled(String provider) {
Toast.makeText(this, "New provider enabled: " + provider, Toast.LENGTH_SHORT).show();

}

@Override
public void onStatusChanged(String arg0, int arg1, Bundle arg2) {
// TODO Auto-generated method stub

}
/* @Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.show_location, menu);
return true;
}
*/
}

</pre>

== Code Variante ==
In diesem Beispiel implementiert nicht die Activity das LocationListener Interface, sondern wir nutzen eine separate Klasse LocListenerDisplay, die für den LocationListener und das Anzeigen der Daten zuständig ist.

Dies sorgt für bessere Trennung der Aufgaben und besser wartbaren Code.

<pre>
package de.webmynet.android.simplelocation;

//import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
//import android.view.Menu;
import android.widget.TextView;
import android.widget.Toast;

public class ShowLocationActivity extends Activity{
private TextView tvLatitude;
private TextView tvLongitude;
private LocationManager locManager;
private LocationListener locListenD; //locationListenerDisplay
private String provider;
private Context myContext;

// activity is created...
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_show_location);
myContext = this;
// Text Views abrufen
tvLatitude = (TextView) findViewById(R.id.TextView02);
tvLongitude = (TextView) findViewById(R.id.TextView04);

// LocationManager Service Handle holen
locManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
Location loc = locManager.getLastKnownLocation("gps");

//TVs setzen
if(loc != null){
float lat = (float) (loc.getLatitude());
float lng = (float) (loc.getLongitude());
tvLatitude.setText(String.valueOf(lat));
tvLongitude.setText(String.valueOf(lng));
}else{
tvLatitude.setText("Location is not available");
tvLongitude.setText("Location is not available");
}

// LocationListenerDisplay Objekt initialisieren
locListenD = new LocListenerDisplay();
}

private class LocListenerDisplay implements LocationListener{
@Override
public void onLocationChanged(Location loc) {
float lat = (float) (loc.getLatitude());
float lng = (float) (loc.getLongitude());
tvLatitude.setText(String.valueOf(lat));
tvLongitude.setText(String.valueOf(lng));
}

@Override
public void onProviderDisabled(String provider) {
Toast.makeText(myContext, "onProviderDisabled - disabled provider", Toast.LENGTH_SHORT).show();
}

@Override
public void onProviderEnabled(String provider) {
Toast.makeText(myContext, "onProviderEnebled - New provider: " + provider, Toast.LENGTH_SHORT).show();
}

@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
}

/* Location updates liefern wenn die Activity (neu-)startet */
@Override
protected void onResume() {
super.onResume();
Toast.makeText(this, "RESUME - selected provider: " + provider, Toast.LENGTH_SHORT).show();
locManager.requestLocationUpdates("gps", 600, 20, locListenD);
}

/* locationlistener updates stoppen wenn Activity pausiert sonst gibt es Fehler im Log */
@Override
protected void onPause() {
super.onPause();
locManager.removeUpdates(locListenD);
}
}

</pre>

Android - Cheat Sheet

2013-10-10T14:16:06Z

79.240.23.31:

Hier gibt es nur Code Schnipsel zum Kopieren ohne Erklärung
== Neue Activity ==
=== Activity Class ===
<pre>
package de.webmynet.android.packagename;

import android.app.Activity;
import android.os.Bundle;

public class NameOfActivity extends Activity{

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layoutname);
}
}
</pre>

Android - Cheat Sheet

2013-10-10T14:05:20Z

79.240.23.31: Die Seite wurde neu angelegt: „== Neue Activity ==“

== Neue Activity ==

Android Development - Snippets

2013-10-10T13:50:24Z

79.240.23.31:

== Android Cheat Sheet ==
[[Android - Cheat Sheet]]

== Activities ==
=== Android - Neue Activity anlegen und starten ===
[[Android - Neue Activity]]

== Layouts ==
Lock Portrait or Landscape

fullscreen - requestwindowfeature

=== Handle Orientation ===
[[Android - Handle Orientation]]

== Views ==
=== Vertical Seek Bar ===
[[Android - Vertical Seek Bar]]

== Events ==
[[Android - OnClickListener]]

== Graphic and Animation ==
Bitmap - ressource und input stream

Sprites

== Sound ==
=== Unterstützte Formate ===
* http://developer.android.com/guide/appendix/media-formats.html
=== Links ===
* http://stackoverflow.com/questions/4855874/are-there-any-built-in-default-sounds-that-can-be-utilized-in-an-app
* http://alucard1990.hubpages.com/hub/How-to-Make-a-Simple-Media-Player-for-Android
* http://stackoverflow.com/questions/3747139/how-can-i-show-a-mediacontroller-while-playing-audio-in-android/5265629#5265629

=== Möglichkeiten zur Sound-Ausgabe ===

====SoundPool====

====MediaPlayer====
[[Android - Media Player]]

http://developer.android.com/reference/android/media/MediaPlayer.html

Generate Sound (Midi-Files + PCM Generation mit AudioTrack)
[[Android - rttl Sound File]]
* http://www.speakingcode.com/2012/01/01/playing-with-android-audiotrack-to-generate-sounds/

System Sounds

=== Fortgeschrittene Techniken ===
* http://www.martinhoeller.net/2012/01/13/developing-a-musical-instrument-app-for-android/

* http://docs.gstreamer.com/display/GstSDK/Android+tutorials

* http://www.brokenteapotstudios.com/android-game-development-blog/2011/10/playing-a-wav-pcm-sample-with-audiotrack.html

== Threads ==
* [[Java - Threads]]
* [[Android - Threads]]
* [[Java - Timer und TimerTask]]
* [[Android - Thread Priority]]

== Files, Dateimanagment ==
[[Android - Dateimanagement]]
=== Textdatei erzeugen, speichern, lesen ===
=== Bild erzeugen und speichern ===
http://stackoverflow.com/questions/10278919/android-writing-reading-picture-to-internal-storage?rq=1

[[Android - Bild erzeugen und speichern]]

=== Zugriff auf Ressourcen ===
* http://stackoverflow.com/questions/8340445/how-can-i-specify-the-resource-to-get-from-r-res-drawable-dynamically
Beispiel Speicherkarte:
File.DirRootExternal & "/Music", "titelx.mp3"

==== Ressourcen Pfad herausfinden ====
Ist das richtig ???
Eigentlich muß die Ressource ID in den Filenamen umgewandelt werden.

Using Resource Name

Syntax:

android.resource://[package]/[res type]/[res name]

Example : If icon.png image file is available in res/drawable folder you can get path like :

String PATH="android.resource://com.my.package/drawable/icon";

Using Resource Id

Syntax :
android.resource://[package]/[resource_id]

Example : If icon.png image file is available in res/drawable folder you can get path:

String PATH="android.resource://com.my.package/" + R.drawable.icon;

This were the examples to get the URI of any image file stored in drawable folder.

Similarly you can get URIs of res/raw folder also.

???

== Gestures - Gesten ==
[[Android Development - Gesten]]

== GPS, Geolocation und Maps ==
[[Android Location API]]