Ch16 Listings

android Android

web Web

27-Feb-10 (Created: 27-Feb-10) | More in 'Pro Android 2 Source'

Ch16 Listings

satya - Saturday, February 27, 2010 10:23:46 PM

Listing 16-1


<?xml version="1.0" encoding="utf-8"?>
<!-- This file is res/layout/main.xml -->
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

  <RelativeLayout 
    android:id="@+id/layout1"
    android:tag="trueLayoutTop"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:layout_weight="1"
    >

    <com.androidbook.touch.demo1.TrueButton android:text="returns true" 
    android:id="@+id/trueBtn1"
    android:tag="trueBtnTop"
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" />
    
    <com.androidbook.touch.demo1.FalseButton android:text="returns false"
    android:id="@+id/falseBtn1" 
    android:tag="falseBtnTop"
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content"
    android:layout_below="@id/trueBtn1" />
    
  </RelativeLayout>
  <RelativeLayout 
    android:id="@+id/layout2"
    android:tag="falseLayoutBottom"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:layout_weight="1"
    android:background="#FF00FF"
    >

    <com.androidbook.touch.demo1.TrueButton android:text="returns true" 
    android:id="@+id/trueBtn2"
    android:tag="trueBtnBottom"
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" />
    
    <com.androidbook.touch.demo1.FalseButton android:text="returns false"
    android:id="@+id/falseBtn2" 
    android:tag="falseBtnBottom"
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content"
    android:layout_below="@id/trueBtn2" />
    
  </RelativeLayout>
</LinearLayout>

satya - Saturday, February 27, 2010 10:24:37 PM

Listing 16-2 a


// This file is BooleanButton.java
import android.content.Context;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.widget.Button;

public abstract class BooleanButton extends Button {
    protected boolean myValue() {
        return false;
    }

    public BooleanButton(Context context, AttributeSet attrs) {
        super(context, attrs);
    }
    
    @Override
    public boolean onTouchEvent(MotionEvent event) {
        String myTag = this.getTag().toString();
        Log.v(myTag, "-----------------------------------");
        Log.v(myTag, MainActivity.describeEvent(this, event));
        Log.v(myTag, "super onTouchEvent() returns " + super.onTouchEvent(event));
        Log.v(myTag, "and I'm returning " + myValue());
        event.recycle();
        return(myValue());
    }
}

satya - Saturday, February 27, 2010 10:24:58 PM

Listing 16-2 b


// This file is TrueButton.java
import android.content.Context;
import android.util.AttributeSet;

public class TrueButton extends BooleanButton {
    protected boolean myValue() {
        return true;
    }
    
    public TrueButton(Context context, AttributeSet attrs) {
        super(context, attrs);
    }
}

satya - Saturday, February 27, 2010 10:25:21 PM

Listing 16-2 c


// This file is FalseButton.java
import android.content.Context;
import android.util.AttributeSet;

public class FalseButton extends BooleanButton {

    public FalseButton(Context context, AttributeSet attrs) {
        super(context, attrs);
    }
}

satya - Saturday, February 27, 2010 10:28:03 PM

Listing 16-3


// This file is MainActivity.java
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.Button;
import android.widget.RelativeLayout;

public class MainActivity extends Activity implements OnTouchListener {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        RelativeLayout layout1 = (RelativeLayout) findViewById(R.id.layout1);
        layout1.setOnTouchListener(this);
        Button trueBtn1 = (Button)findViewById(R.id.trueBtn1);
        trueBtn1.setOnTouchListener(this);
        Button falseBtn1 = (Button)findViewById(R.id.falseBtn1);
        falseBtn1.setOnTouchListener(this);

        RelativeLayout layout2 = (RelativeLayout) findViewById(R.id.layout2);
        layout2.setOnTouchListener(this);
        Button trueBtn2 = (Button)findViewById(R.id.trueBtn2);
        trueBtn2.setOnTouchListener(this);
        Button falseBtn2 = (Button)findViewById(R.id.falseBtn2);
        falseBtn2.setOnTouchListener(this);
    }

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        String myTag = v.getTag().toString();
        Log.v(myTag, "-----------------------------");
        Log.v(myTag, "Got view " + myTag + " in onTouch");
        Log.v(myTag, describeEvent(v, event));
        if( "true".equals(myTag.substring(0, 4))) {
            Log.v(myTag, "and I'm returning true");
            return true;
        }
        else {
            Log.v(myTag, "and I'm returning false");
            return false;
        }
    }
    
    protected static String describeEvent(View view, MotionEvent event) {
        StringBuilder result = new StringBuilder(300);
        result.append("Action: ").append(event.getAction()).append("\n");
        result.append("Location: ").append(event.getX()).append(" x ").append(event.getY()).append("\n");
        if(    event.getX() < 0 || event.getX() > view.getWidth() ||
                event.getY() < 0 || event.getY() > view.getHeight()) {
            result.append(">>> Touch has left the view <<<\n");
        }
        result.append("Edge flags: ").append(event.getEdgeFlags()).append("\n");
        result.append("Pressure: ").append(event.getPressure()).append("   ");
        result.append("Size: ").append(event.getSize()).append("\n");
        result.append("Down time: ").append(event.getDownTime()).append("ms\n");
        result.append("Event time: ").append(event.getEventTime()).append("ms");
        result.append("  Elapsed: ").append(event.getEventTime()-event.getDownTime());
        result.append(" ms\n");
        return result.toString();
    }
}

satya - Saturday, February 27, 2010 10:30:34 PM

Listing 16-8


private VelocityTracker vTracker = null;

@Override
public boolean onTouchEvent(MotionEvent event) {
    int action = event.getAction();
    switch(action) {
        case MotionEvent.ACTION_DOWN:
            if(vTracker == null) {
                vTracker = VelocityTracker.obtain();
            }
            else {
                vTracker.clear();
            }
            vTracker.addMovement(event);
            break;
        case MotionEvent.ACTION_MOVE:
            vTracker.addMovement(event);
            vTracker.computeCurrentVelocity(1000);
            Log.v(TAG, "X velocity is " + vTracker.getXVelocity() + " pixels per second");
            Log.v(TAG, "Y velocity is " + vTracker.getYVelocity() + " pixels per second");
            break;
        case MotionEvent.ACTION_UP:
        case MotionEvent.ACTION_CANCEL:
            vTracker.recycle();
            break;
    }
    event.recycle();
    return true;
}

satya - Saturday, February 27, 2010 10:32:02 PM

Listing 16-9


import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;

public class Dot extends View {
    private static final float RADIUS = 20;
    private float x = 30;
    private float y = 30;
    private float initialX;
    private float initialY;
    private float offsetX;
    private float offsetY;
    private Paint backgroundPaint;
    private Paint myPaint;
    
    public Dot(Context context, AttributeSet attrs) {
        super(context, attrs);

        backgroundPaint = new Paint();
        backgroundPaint.setColor(Color.BLUE);

        myPaint = new Paint();
        myPaint.setColor(Color.WHITE);
        myPaint.setAntiAlias(true);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        int action = event.getAction();
        switch(action) {
        case MotionEvent.ACTION_DOWN:
            // Need to remember where the initial starting point
            // center is of our Dot and where our touch starts from
            initialX = x;
            initialY = y;
            offsetX = event.getX();
            offsetY = event.getY();
            break;
        case MotionEvent.ACTION_MOVE:
        case MotionEvent.ACTION_UP:
        case MotionEvent.ACTION_CANCEL:
            x = initialX + event.getX() - offsetX;
            y = initialY + event.getY() - offsetY;
            break;
        }
        event.recycle();
        return(true);
    }

    @Override
    public void draw(Canvas canvas) {
        int width = canvas.getWidth();
        int height = canvas.getHeight();
        canvas.drawRect(0, 0, width, height, backgroundPaint);

        canvas.drawCircle(x, y, RADIUS, myPaint);
        invalidate();
    }
}

satya - Saturday, February 27, 2010 10:32:35 PM

Listing 16-9


<?xml version="1.0" encoding="utf-8"?>
<!-- This file is res/layout/main.xml -->
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >

  <com.androidbook.touch.dragdemo1.Dot
    android:id="@+id/dot"
    android:tag="trueDot"
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" />

</LinearLayout>

satya - Saturday, February 27, 2010 10:33:04 PM

Listing 16-10


// This file is MainActivity.java
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.RelativeLayout;

public class MainActivity extends Activity implements OnTouchListener {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        RelativeLayout layout1 = (RelativeLayout) findViewById(R.id.layout1);
        layout1.setOnTouchListener(this);
    }

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        String myTag = v.getTag().toString();
        Log.v(myTag, "-----------------------------");
        Log.v(myTag, "Got view " + myTag + " in onTouch");
        Log.v(myTag, describeEvent(event));
        if( "true".equals(myTag.substring(0, 4))) {
            Log.v(myTag, "and I'm returning true");
            return true;
        }
        else {
            Log.v(myTag, "and I'm returning false");
            return false;
        }
    }
    
    protected static String describeEvent(MotionEvent event) {
        StringBuilder result = new StringBuilder(500);
        result.append("Action: ").append(event.getAction()).append("\n");
        int numPointers = event.getPointerCount();
        result.append("Number of pointers: ").append(numPointers).append("\n");
        int ptrIdx = 0;
        while (ptrIdx < numPointers) {
            int ptrId = event.getPointerId(ptrIdx);
            result.append("Pointer Index: ").append(ptrIdx);
            result.append(", Pointer Id: ").append(ptrId).append("\n");
            result.append("   Location: ").append(event.getX(ptrIdx));
            result.append(" x ").append(event.getY(ptrIdx)).append("\n");
            result.append("   Pressure: ").append(event.getPressure(ptrIdx));
            result.append("   Size: ").append(event.getSize(ptrIdx)).append("\n");

            ptrIdx++;
        }
        result.append("Downtime: ").append(event.getDownTime()).append("ms\n");
        result.append("Event time: ").append(event.getEventTime()).append("ms");
        result.append("  Elapsed: ").append(event.getEventTime()-event.getDownTime());
        result.append(" ms\n");
        return result.toString();
    }
}

satya - Saturday, February 27, 2010 10:33:33 PM

Listing 16-10 xml


<?xml version="1.0" encoding="utf-8"?>
<!-- This file is /res/layout/main.xml -->
<RelativeLayout  xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/layout1"
    android:tag="trueLayout"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:layout_weight="1"
    >

    <TextView android:text="Touch fingers on the screen and look at LogCat"
    android:id="@+id/message" 
    android:tag="trueText"
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true" />
    
</RelativeLayout>

satya - Saturday, February 27, 2010 10:34:17 PM

Listing 16-12


int action = event.getAction();
    int ptrId = event.getPointerId(0);
    if(event.getPointerCount() > 1)
        ptrId = (action & MotionEvent.ACTION_POINTER_ID_MASK) >>>
                                      MotionEvent.ACTION_POINTER_ID_SHIFT;
    action = action & MotionEvent.ACTION_MASK;
    if(action < 7 && action > 4)
        action = action - 5;
    int ptrIndex = event.findPointerIndex(ptrId);

satya - Saturday, February 27, 2010 10:34:56 PM

Listing 16-13 a


@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.mapview);

        mapView = (MapView)findViewById(R.id.mapview);

        ClickReceiver clickRecvr = new ClickReceiver(this);
        mapView.getOverlays().add(clickRecvr);
    }

satya - Saturday, February 27, 2010 10:44:57 PM

Listing 16-13 b


// This file is ClickReceiver.java
import android.content.Context;
import android.content.Intent;
import android.net.Uri;
import android.util.Log;

import com.google.android.maps.GeoPoint;
import com.google.android.maps.MapView;
import com.google.android.maps.Overlay;

public class ClickReceiver extends Overlay{
    private static final String TAG = "ClickReceiver";
    private Context context;

    public ClickReceiver(Context _context) {
        context = _context;
    }
    
    @Override
    public boolean onTap(GeoPoint p, MapView mapView) {
        Log.v(TAG, "Received a click at this point: " + p);
        
        if(mapView.isStreetView()) {
            Intent myIntent = new Intent(Intent.ACTION_VIEW, Uri.parse
                ("google.streetview:cbll=" +
                (float)p.getLatitudeE6() / 1000000f +
                "," + (float)p.getLongitudeE6() / 1000000f
                +"&cbp=1,180,,0,1.0"
                ));
            context.startActivity(myIntent);
             return true;
        }
        return false;
    }
}

satya - Saturday, February 27, 2010 10:45:29 PM

Listing 16-14


import java.util.ArrayList;
import android.app.Activity;
import android.gesture.Gesture;
import android.gesture.GestureLibraries;
import android.gesture.GestureLibrary;
import android.gesture.GestureOverlayView;
import android.gesture.Prediction;
import android.gesture.GestureOverlayView.OnGesturePerformedListener;
import android.os.Bundle;
import android.util.Log;
import android.widget.Toast;

public class MainActivity extends Activity implements OnGesturePerformedListener {
    private static final String TAG = "Gesture Revealer";
    GestureLibrary gestureLib = null;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

//        gestureLib = GestureLibraries.fromRawResource(this, R.raw.gestures);
        gestureLib = GestureLibraries.fromFile("/sdcard/gestures");
        if (!gestureLib.load()) {
            Toast.makeText(this, "Could not load /sdcard/gestures", Toast.LENGTH_SHORT).~CCC
                        show();
            finish();
        }
        
        // Let's take a look at the gesture library we have work with
        Log.v(TAG, "Library features:");
        Log.v(TAG, "  Orientation style: " + gestureLib.getOrientationStyle());
        Log.v(TAG, "  Sequence type: " + gestureLib.getSequenceType());
        for( String gestureName : gestureLib.getGestureEntries() ) {
            Log.v(TAG, "For gesture " + gestureName);
            int i = 1;
            for( Gesture gesture : gestureLib.getGestures(gestureName) ) {
                Log.v(TAG, "    " + i + ": ID: " + gesture.getID());
                Log.v(TAG, "    " + i + ": Strokes count: " + gesture.getStrokesCount());
                Log.v(TAG, "    " + i + ": Stroke length: " + gesture.getLength());
                i++;
            }
        }
        
        GestureOverlayView gestureView = ~CCC
                (GestureOverlayView) findViewById(R.id.gestureOverlay);
        gestureView.addOnGesturePerformedListener(this);
    }

    @Override
    public void onGesturePerformed(GestureOverlayView view, Gesture gesture) {
        ArrayList<Prediction> predictions = gestureLib.recognize(gesture);

        if (predictions.size() > 0) {
            Prediction prediction = (Prediction) predictions.get(0);
            if (prediction.score > 1.0) {
                Toast.makeText(this, prediction.name, Toast.LENGTH_SHORT).show();
                for(int i=0;i<predictions.size();i++)
                    Log.v(TAG, "prediction " + predictions.get(i).name + 
                            " - score = " + predictions.get(i).score);
            }
        }
    }
}

satya - Saturday, February 27, 2010 10:46:00 PM

Listing 16-14


<?xml version="1.0" encoding="utf-8"?>
<!-- This file is /res/layout/main.xml -->
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="Draw gestures and I'll guess what they are"
    />
    
<android.gesture.GestureOverlayView
    android:id="@+id/gestureOverlay"
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent"
    android:gestureStrokeType="multiple"
    android:fadeOffset="1000" />

</LinearLayout>