四、融入多媒体元素

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/bglight" >
<TableLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true" >
<TableRow
android:id="@+id/tableRow1"
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="1" >
<ImageView
android:id="@+id/imagenumber"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:src="@drawable/no0" />
TableRow>
<TableRow
android:id="@+id/tableRow2"
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="1" >
<ImageButton
android:id="@+id/btnprevious"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:src="@drawable/prev" />
<ImageButton
android:id="@+id/btninfo"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:src="@drawable/info" />
<ImageButton
android:id="@+id/btnsound"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:src="@drawable/sound" />
<ImageButton
android:id="@+id/btnnext"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:src="@drawable/next" />
TableRow>
TableLayout>
RelativeLayout>


public class SimpleNumb3r5 extends Activity implements OnClickListener


//initialize all widgets
private ImageView imagenumber;
private ImageButton btnprevious, btninfo, btnsound, btnnext;
//define variables to track screen number, start from 0
private int screennumber=0;
//define a sound controller
private MediaPlayer mp;
//define an array for the sound files
private String[] soundfile={"0.mp3","1.mp3","2.mp3","3.mp3",
"4.mp3","5.mp3","6.mp3","7.mp3","8.mp3","9.mp3"};


public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_simple_numb3r5);
imagenumber=(ImageView)findViewById(R.id.imagenumber);
//create the object for the button
btnprevious=(ImageButton)findViewById(R.id.btnprevious);
//this button will initially be disabled
btnprevious.setEnabled(false);
//add listener to the button
btnprevious.setOnClickListener(this);
btninfo=(ImageButton)findViewById(R.id. btninfo);
btninfo.setOnClickListener(this);
btnsound=(ImageButton)findViewById(R.id.btnsound);
btnsound.setOnClickListener(this);
btnnext=(ImageButton)findViewById(R.id.btnnext);
btnnext.setOnClickListener(this);
}//end onCreate


//this method is to handle button click
public void onClick(View arg0) {
//when btnprevious is clicked
if(arg0.getId()==R.id.btnprevious){
screennumber--;// Decrement 1 to the screennumber
changeNumber(screennumber);
if(screennumber==0){
// Disable previous Button
btnprevious.setEnabled(false);
}else{
// Enable back disabled Button.
btnprevious.setEnabled(true);
}
changeNumber(screennumber);
btnnext.setEnabled(true);
}
//when btnnext is clicked
else if(arg0.getId()==R.id.btnnext){
screennumber++;//add 1 to the screennumber
changeNumber(screennumber);
if(screennumber==9){
Disable no screen available next
btnnext.setEnabled(false);
}else{
/ Only prevoius screen available
btnnext.setEnabled(true);
}
changeNumber(screennumber);
btnprevious.setEnabled(true);
}
//when btnplay is clicked
else if(arg0.getId()==R.id.btnsound){
//playSound - will implement later
}
else if(arg0.getId()==R.id.btninfo){
//display info will implement later
}
}//end onClick


//this method is to change the number that appears on the screen
// after the navigation button is clicked
// as R.id retuns int so we use switch
private void changeNumber(int screen){
switch (screen){
case 0: imagenumber.setImageResource(R.drawable.no0);
break;
case 1: imagenumber.setImageResource(R.drawable.no1);
break;
case 2: imagenumber.setImageResource(R.drawable.no2);
break;
case 3: imagenumber.setImageResource(R.drawable.no3);
break;
case 4: imagenumber.setImageResource(R.drawable.no4);
break;
case 5: imagenumber.setImageResource(R.drawable.no5);
break;
case 6: imagenumber.setImageResource(R.drawable.no6);
break;
case 7: imagenumber.setImageResource(R.drawable.no7);
break;
case 8: imagenumber.setImageResource(R.drawable.no8);
break;
case 9: imagenumber.setImageResource(R.drawable.no9);
break;
}
}//end changeNumber


//when btnplay is clicked
else if(arg0.getId()==R.id.btnsound){
//call the method playSound
playSound(soundfile[screennumber].toString());
}//end btnsound clicked


public void playSound(String soundName){
Boolean mpPlayingStatus;
try{//try to check MediaPlayer status
mpPlayingStatus=mp.isPlaying();
}
catch (Exception e){
mpPlayingStatus=false;
}
//if the MediaPlayer is playing a sound, stop it to play new voice
if(mp.isPlaying()){
mp.stop(); //stop the sound
mp.release(); //remove sound from the memory
}
else{
try{
mp = new MediaPlayer();
AssetFileDescriptor afd = getAssets().openFd(soundName);
//set the sound source file
FileDescriptor fd = afd.getFileDescriptor();
mp.setDataSource(fd);
mp.prepare(); // prepare for playback
mp.start(); //play the sound
}//try block
catch(IOException e) {
//display the error message in debug
Log.i("Error playing sound: ", e.toString());
}
}
}//end playSound


package net.kerul.simplenumb3r5;
import android.app.Activity;
import android.os.Bundle;
import android.webkit.WebView;
public class Info extends Activity {
private WebView webinfo;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_info);
webinfo=(WebView)findViewById(R.id.webinfo);
//provide the URL path pointing to info.html
webinfo.loadUrl("file:///android_asset/info.html");
}
}


else if(arg0.getId()==R.id.btninfo){
//invoke the Info activity
Intent info = new Intent(this, Info.class);
startActivity(info);
}Adding Activity in Manifest file


<activity
android:name=".Info"
android:label="@string/title_activity_info" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category
android:name="android.intent.category.LAUNCHER" />
intent-filter>
activity>


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