Develop Reference

A reset Button on canvas

I need to make a Button that cleans my canvas and also a safe button.
I would like that the Activity stays like it is . And just Path what was drawn would be deleted.Thank you so much for any help. My Code:
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
public class TouchEventDraw extends View {
//Variable
private Paint paint = new Paint();
private Path path = new Path();
//Konstruktor
public TouchEventDraw(Context context, AttributeSet attrset) {
super(context, attrset);
paint.setAntiAlias(true);
paint.setColor(Color.BLACK);
paint.setStrokeJoin(Paint.Join.MITER);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(5f);
}
/**
* The most important step in drawing a custom view is to override the
* #param canvas object that the view can use to draw itself. */
#Override
protected void onDraw(Canvas canvas) {
if(path.isEmpty())
canvas.drawColor(Color.WHITE);
else
canvas.drawPath(path, paint);
}
/**
* Method to handle touch screen motion events.
* #param event The motion event
* #return True if the event was handled, false otherwise.*/
#Override
public boolean onTouchEvent(MotionEvent event) {
float xPos = event.getX();
float yPos = event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
path.moveTo(xPos,yPos);
return true;
case MotionEvent.ACTION_MOVE:
path.lineTo(xPos,yPos);
break;
case MotionEvent.ACTION_UP:
break;
default:
return false;
}
invalidate();
return true;
}
public void clear(){
path = new Path();
invalidate();
}
}
And my Activity with Buttons:
import android.graphics.Canvas;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
public class DrawingScreen extends AppCompatActivity {
Button btn;
TouchEventDraw ted;
Canvas canva;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ted=new TouchEventDraw(this,null);
setContentView(R.layout.activity_drawing_screen);
btn=(Button) findViewById(R.id.button);
btn.setOnClickListener(onClickListener);
}
private final View.OnClickListener onClickListener=new View.OnClickListener() {
#Override
public void onClick(View v) {
ted.clear();
ted.invalidate();
}
};
}

You need to add a method to your TouchEventDraw class, and call the following in it
canva.drawColor(Color.WHITE);
Then on your button click, call the method you created.
You should be able to implement the solution with the information I supplied.
I think there are more fatal issues through your code though, as I see the following:
The view is never being put on screen.
You extend View, rather than SurfaceView.
Another way, you should be able to create a method, and instead set path empty
public void clear(){
path = new Path();
}
then change your draw to
#Override
protected void onDraw(Canvas canvas) {
if(path.isEmpty())
canvas.drawColor(Color.WHITE);
else
canvas.drawPath(path, paint);
}
and call View.invalidate();

Android triangle custom buttons

I want to make 2 diagonal triangle buttons like in this question.
How can I achieve this? Should I make a drawable xml with a rectangle and rotate it somehow? Should I make an image and make it clickable only on the triangle parts with the help of mathematics?

package com.example.buttonsView;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.Path.FillType;
import android.graphics.Point;
import android.graphics.RectF;
import android.graphics.Region;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
public class TwoButtons extends View {
private Path path;
private Path path1;
private Region region;
private Region region1;
private static int GAP=10;
private ButtonClickEvents buttonClickEvent;
public interface ButtonClickEvents{
public void redButtonClick();
public void blueButtonClick();
}
public void setOnButtonClickEvent(ButtonClickEvents buttonClickEvent) {
this.buttonClickEvent=buttonClickEvent;
}
public TwoButtons(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
private void init() {
}
#Override
protected void onDraw(Canvas canvas) {
// TODO Auto-generated method stub
super.onDraw(canvas);
canvas.drawColor(Color.GRAY);
Paint paint = new Paint();
paint.setColor(android.graphics.Color.BLACK);
canvas.drawPaint(paint);
paint.setStrokeWidth(0);
paint.setColor(android.graphics.Color.RED);
paint.setStyle(Paint.Style.FILL_AND_STROKE);
paint.setAntiAlias(true);
Point a = new Point(GAP, GAP);
Point b = new Point(GAP, getHeight()-2*GAP);
Point c = new Point(getWidth()-2*GAP, GAP);
path = new Path();
path.setFillType(FillType.EVEN_ODD);
path.moveTo(a.x, a.y);
path.lineTo(b.x, b.y);
path.lineTo(c.x, c.y);
path.close();
canvas.drawPath(path, paint);
RectF rectF = new RectF();
path.computeBounds(rectF, true);
region = new Region();
region.setPath(path, new Region((int) rectF.left, (int) rectF.top, (int) rectF.right, (int) rectF.bottom));
paint.setColor(Color.BLUE);
Point a1 = new Point(getWidth()-GAP, getHeight()-GAP);
Point b1 = new Point(getWidth()-GAP, 2*GAP);
Point c1 = new Point(2*GAP, getHeight()-GAP);
path1 = new Path();
path1.setFillType(FillType.EVEN_ODD);
path1.moveTo(a1.x, a1.y);
path1.lineTo(b1.x, b1.y);
path1.lineTo(c1.x, c1.y);
path1.close();
canvas.drawPath(path1, paint);
RectF rectF1 = new RectF();
path1.computeBounds(rectF1, true);
region1 = new Region();
region1.setPath(path1, new Region((int) rectF1.left, (int) rectF1.top, (int) rectF1.right, (int) rectF1.bottom));
}
#Override
public boolean onTouchEvent(MotionEvent event) {
// TODO Auto-generated method stub
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
Point point = new Point();
point.x = (int) event.getX();
point.y = (int) event.getY();
invalidate();
if(region.contains((int)point.x,(int) point.y))
{
if(buttonClickEvent!=null)
buttonClickEvent.redButtonClick();
}else if(region1.contains((int)point.x,(int) point.y))
{
if(buttonClickEvent!=null)
buttonClickEvent.blueButtonClick();
}
return true;
}
return false;
}
}
activity_main.xml
<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:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.example.buttonsView.MainActivity" >
<com.example.buttonsView.TwoButtons
android:id="#+id/twoButtons1"
android:layout_width="200dp"
android:layout_height="200dp"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true" />
</RelativeLayout>
MainActivity.java
package com.example.buttonsView;
import android.app.Activity;
import android.os.Bundle;
import android.widget.Toast;
import com.afbb.preferencessample.R;
import com.example.buttonsView.TwoButtons.ButtonClickEvents;
public class MainActivity extends Activity {
TwoButtons buttons;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
buttons = (TwoButtons) findViewById(R.id.twoButtons1);
buttons.setOnButtonClickEvent(new ButtonClickEvents() {
#Override
public void redButtonClick() {
// TODO Auto-generated method stub
Toast.makeText(getApplicationContext(), "red",
Toast.LENGTH_SHORT).show();
}
#Override
public void blueButtonClick() {
// TODO Auto-generated method stub
Toast.makeText(getApplicationContext(), "blue",
Toast.LENGTH_SHORT).show();
}
});
}
}
output :

Changing path color without changing previous paths

I made straight lines with the canvas.drawPath command. But now I want that the color is selectable. So you click on a button and afterwards, the path is in this color, but the previous paths remain in their colors.. The thin with the button comes later, the colour is random at the moment...
I did it, i changed the code from here! Change path color without changing previous paths
Main Activity
package com.example.drawproject;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.app.ActionBar;
import android.support.v4.app.Fragment;
import android.app.Activity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.os.Build;
public class MainActivity extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
DrawArea da = new DrawArea(this);
setContentView(da);
}
}
Draw Activity
import android.content.Context;
import android.graphics.*;
import android.util.SparseArray;
import android.view.MotionEvent;
import android.view.View;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
public class DrawArea extends View {
private List<Stroke> _allStrokes; //all strokes that need to be drawn
private SparseArray<Stroke> _activeStrokes; //use to retrieve the currently drawn strokes
private Random _rdmColor = new Random();
int count = 1;
public DrawArea(Context context) {
super(context);
_allStrokes = new ArrayList<Stroke>();
_activeStrokes = new SparseArray<Stroke>();
setFocusable(true);
setFocusableInTouchMode(true);
}
public void onDraw(Canvas canvas) {
if (_allStrokes != null) {
for (Stroke stroke: _allStrokes) {
if (stroke != null) {
Path path = stroke.getPath();
Paint painter = stroke.getPaint();
if ((path != null) && (painter != null)) {
if(count%2 != 0){
canvas.drawPath(path, painter);
}
}
}
}
}
}
#Override
public boolean onTouchEvent(MotionEvent event) {
final int action = event.getActionMasked();
final int pointerCount = event.getPointerCount();
switch (action) {
case MotionEvent.ACTION_DOWN: {
count++;
if(count%2 != 1)
{pointDown((int)event.getX(), (int)event.getY(), event.getPointerId(0));
break;
}
if (count%2 != 0){
for (int pc = 0; pc < pointerCount; pc++) {
pointDown((int)event.getX(pc), (int)event.getY(pc), event.getPointerId(pc));
}
}
}
case MotionEvent.ACTION_MOVE: {
break;
}
case MotionEvent.ACTION_UP: {
break;
}
}
invalidate();
return true;
}
private void pointDown(int x, int y, int id) {
if(count%2 !=1){
//create a paint with random color
Paint paint = new Paint();
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(10);
paint.setColor(_rdmColor.nextInt());
//create the Stroke
Point pt = new Point(x, y);
Stroke stroke = new Stroke(paint);
stroke.addPoint(pt);
_activeStrokes.put(id, stroke);
_allStrokes.add(stroke);
}
if (count%2 != 0){
//retrieve the stroke and add new point to its path
Stroke stroke = _activeStrokes.get(id);
if (stroke != null) {
Point pt = new Point(x, y);
stroke.addPoint(pt);
}
}
}
}
Lines
package com.example.drawproject;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.Point;
public class Stroke {
private Path _path;
private Paint _paint;
public Stroke (Paint paint) {
_paint = paint;
}
public Path getPath() {
return _path;
}
public Paint getPaint() {
return _paint;
}
public void addPoint(Point pt) {
if (_path == null) {
_path = new Path();
_path.moveTo(pt.x, pt.y);
} else {
_path.lineTo(pt.x, pt.y);
}
}
}

For each path declare separate paint object and change paint object of the path that you want to change.
canvas.drawPath(path1, paint1);
canvas.drawPath(path2, paint2);
canvas.drawPath(path3, paint3);
canvas.drawPath(path4, paint4);
The main idea:
public class temp extends View{
private Map<Path,Paint> MyMap = new HashMap<Path,Paint>();
public ViewFeld(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
init();
}
private void init() {
for (int i = 0; i < number of pathes ; i++) {
Path path = new Path();
paint = new Paint();
paint.setColor(Color.MAGENTA);
paint.setStrokeWidth(2);
paint.setStyle(Paint.Style.FILL);
MyMap.put(path, paint);
}
}
protected void onDraw(Canvas canvas) {
for (Path p : MyMap.keySet()) {
canvas.drawPath(p, MyMap.get(p));
}
}
#Override
public boolean onTouchEvent(MotionEvent event) {
float eventX = event.getX();
float eventY = event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
Paint p = MyMap.get(path you want to change the color);
// change the color of p
case MotionEvent.ACTION_MOVE:
break;
case MotionEvent.ACTION_UP:
// nothing to do
break;
default:
return false;
}
// Schedules a repaint.
invalidate();
return true;
}

How to clear canvas in android on button click

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
public class SingleTouchEventView extends View {
private Paint paint = new Paint();
private Path path = new Path();
public boolean cc = false;
public SingleTouchEventView(Context context, AttributeSet attrs) {
super(context, attrs);
paint.setAntiAlias(true);
paint.setStrokeWidth(18f);
paint.setColor(Color.LTGRAY);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeJoin(Paint.Join.ROUND);
paint.setStrokeCap(Paint.Cap.ROUND);
}
#Override
protected void onDraw(Canvas canvas) {
if(cc)
{
Bitmap back = BitmapFactory.decodeResource(getResources(), R.drawable.black_square);
Bitmap cb = Bitmap.createScaledBitmap(back, 0, 0, false);
canvas.drawBitmap(cb,0,0,null);
cc = false;
}
canvas.drawPath(path, paint);
}
public void clearCanvas()
{
cc =true;
invalidate();
}
#Override
public boolean onTouchEvent(MotionEvent event) {
float eventX = event.getX();
float eventY = event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
path.moveTo(eventX, eventY);
return true;
case MotionEvent.ACTION_MOVE:
path.lineTo(eventX, eventY);
break;
case MotionEvent.ACTION_UP:
// nothing to do
break;
default:
return false;
}
// Schedules a repaint.
invalidate();
return true;
}
}
The above file is my SingleTouchEventView.Java
Here is my MainActivity.java
public class MainActivity extends Activity {
Button reset;;
LinearLayout canvasAlphabets;
SingleTouchEventView myView;
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
reset = (Button)findViewById(R.id.reset_canvas);
myView = new SingleTouchEventView(this, null);
canvasAlphabets = (LinearLayout)findViewById(R.id.canvas_Alphabets);
canvasAlphabets.addView(myView);
reset.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
}
});
}
}
My question is what code should I use in reset button to delete all contents of canvas.
Please help me
I have tried implementing myView.clearCanvas() but that doesn't help. If I add this code to reset buutons on Click it causes FC
Thanks

path = new Path();
Paint clearPaint = new Paint();
clearPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.CLEAR));
canvas.drawRect(0, 0, 0, 0, clearPaint);
cc = false;
I got it fixed with above code

Maybe I do not understand what you want to draw, but have you tried this:
protected void onDraw(Canvas canvas)
{
if (cc)
{
Bitmap back = BitmapFactory.decodeResource(getResources(), R.drawable.black_square);
Bitmap cb = Bitmap.createScaledBitmap(back, 0, 0, false);
canvas.drawBitmap(cb,0,0,null);
cc = false;
}
else
canvas.drawPath(path, paint);
}
}
Otherwise, if you want to erase all, you can use this new paint:
Paint transparent = new Paint();
transparent.setAlpha(0);

You can panit everything with a transparent color, to clear everything.

Android:How to add a button in surface view

I'm drawing some graphics and i would like to add a couple of buttons to it. But with the surface view how do we add these buttons programatically ?

Enclose your surfaceView with a FrameLayout in your xml Layout. Then add your buttons to the same FrameLayout. Make sure they are placed below the surface view so they get drawn on top of it. (Might be a good idea to bundle them in another Layout and add that to the FrameLayout.)
<FrameLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<SurfaceView android:id="#+id/surfaceView1" android:layout_width="wrap_content" android:layout_height="wrap_content"></SurfaceView>
<LinearLayout android:id="#+id/linearLayout1" android:layout_width="wrap_content" android:layout_height="wrap_content">
<Button android:text="Button" android:id="#+id/button1" android:layout_width="wrap_content" android:layout_height="wrap_content"></Button>
<Button android:text="Button" android:id="#+id/button2" android:layout_width="wrap_content" android:layout_height="wrap_content"></Button>
</LinearLayout>
</FrameLayout>

Thank you so much Androidica..
Your xml has helped me to figure out the following solution programatically without using any xml..
public class LudoActivity extends Activity implements OnClickListener {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
FrameLayout game = new FrameLayout(this);
GameView gameView = new GameView (this);
LinearLayout gameWidgets = new LinearLayout (this);
Button endGameButton = new Button(this);
TextView myText = new TextView(this);
endGameButton.setWidth(300);
endGameButton.setText("Start Game");
myText.setText("rIZ..i");
gameWidgets.addView(myText);
gameWidgets.addView(endGameButton);
game.addView(gameView);
game.addView(gameWidgets);
setContentView(game);
endGameButton.setOnClickListener(this);
}
public void onClick(View v) {
Intent intent = new Intent(this, LudoActivity.class);
startActivity(intent);
// re-starts this activity from game-view. add this.finish(); to remove from stack
}
}
while GameView is;
public class GameView extends SurfaceView {
public GameView(Context context) {
super(context);
/*
* your code
*/
}
}

Make your own button:
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.RectF;
public class GButton
{
public Matrix btn_matrix = new Matrix();
public RectF btn_rect;
float width;
float height;
Bitmap bg;
public GButton(float width, float height, Bitmap bg)
{
this.width = width;
this.height = height;
this.bg = bg;
btn_rect = new RectF(0, 0, width, height);
}
public void setPosition(float x, float y)
{
btn_matrix.setTranslate(x, y);
btn_matrix.mapRect(btn_rect);
}
public void draw(Canvas canvas)
{
canvas.drawBitmap(bg, btn_matrix, null);
}
}
on touch event:
float x = ev.getX();
float y = ev.getY();
if (my_button.btn_rect.contains(x, y))
{
// handle on touch here
}
alternatively, even better, if you want to also rotate the button it will not be axis-aligned, then use the invert matrix, instead of mapRect map the touch points x,y:
float pts[] = {x, y};
my_button.invert_matrix.mapPoints(pts);
if (my_button.btn_rect.contains(pts[0], pts[1])
{
// handle on touch here
}

We can use frame layout for surface view drawing very easily .
like this
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<FrameLayout
android:id="#+id/frameLayout"
android:layout_width="fill_parent"
android:layout_height="430dp"/>
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="50dp"
android:gravity="center_horizontal"
android:layout_gravity="bottom"
android:background="#c2300f">
<Button
android:id="#+id/buttonColor"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Color" />
</LinearLayout>
</LinearLayout>
And Main activity is
package com.example.surfacetuto;
import android.app.Activity;
import android.graphics.Paint;
import android.graphics.Point;
import android.os.Bundle;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.FrameLayout;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends Activity implements OnClickListener{
DrawingSurface ds;
FrameLayout frm;
Button btnC;
int color=0xfff00000;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ds=new DrawingSurface(this);
setContentView(R.layout.activity_main);
frm=(FrameLayout)findViewById(R.id.frameLayout);
frm.addView(ds);
btnC=(Button)findViewById(R.id.buttonColor);
btnC.setOnClickListener(this);
}
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
switch (v.getId()) {
case R.id.buttonColor:
Toast.makeText(getApplicationContext(), "Color", 2).show();
ds.colorNew();
break;
default:
break;
}
}
}
And Drawing Surface class is
package com.example.surfacetuto;
import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.Paint.Cap;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.MotionEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;
import android.widget.Toast;
public class DrawingSurface extends SurfaceView implements SurfaceHolder.Callback {
Canvas cacheCanvas;
Bitmap backBuffer;
int width, height, clientHeight;
Paint paint;
Context context;
SurfaceHolder mHolder;
public DrawingSurface(Context context) {
super(context);
this.context = context;
init();
}
public DrawingSurface(Context context, AttributeSet attrs) {
super(context, attrs);
this.context = context;
init();
}
private void init() {
mHolder = getHolder();
mHolder.addCallback(this);
}
int lastX, lastY, currX, currY;
boolean isDeleting;
#Override
public boolean onTouchEvent(MotionEvent event) {
super.onTouchEvent(event);
int action = event.getAction();
switch(action & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
lastX = (int) event.getX();
lastY = (int) event.getY();
break;
case MotionEvent.ACTION_MOVE:
if(isDeleting) break;
currX = (int) event.getX();
currY = (int) event.getY();
cacheCanvas.drawLine(lastX, lastY, currX, currY, paint);
lastX = currX;
lastY = currY;
break;
case MotionEvent.ACTION_UP:
if(isDeleting) isDeleting = false;
break;
case MotionEvent.ACTION_POINTER_DOWN:
cacheCanvas.drawColor(Color.WHITE);
isDeleting = true;
break;
case MotionEvent.ACTION_POINTER_UP:
break;
}
draw();
return true;
}
protected void draw() {
if(clientHeight==0) {
clientHeight = getClientHeight();
height = clientHeight;
backBuffer = Bitmap.createBitmap( width, height, Bitmap.Config.ARGB_8888);
cacheCanvas.setBitmap(backBuffer);
cacheCanvas.drawColor(Color.WHITE);
}
Canvas canvas = null;
try{
canvas = mHolder.lockCanvas(null);
canvas.drawBitmap(backBuffer, 0,0, paint);
}catch(Exception ex){
ex.printStackTrace();
}finally{
if(mHolder!=null) mHolder.unlockCanvasAndPost(canvas);
}
}
private int getClientHeight() {
Rect rect= new Rect();
Window window = ((Activity)context).getWindow();
window.getDecorView().getWindowVisibleDisplayFrame(rect);
int statusBarHeight= rect.top;
int contentViewTop= window.findViewById(Window.ID_ANDROID_CONTENT).getTop();
int titleBarHeight= contentViewTop - statusBarHeight;
return ((Activity)context).getWindowManager().getDefaultDisplay().
getHeight() - statusBarHeight - titleBarHeight;
}
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height) {
}
public void surfaceCreated(SurfaceHolder holder) {
width = getWidth();
height = getHeight();
cacheCanvas = new Canvas();
backBuffer = Bitmap.createBitmap( width, height, Bitmap.Config.ARGB_8888);
cacheCanvas.setBitmap(backBuffer);
cacheCanvas.drawColor(Color.WHITE);
paint = new Paint();
paint.setColor(Color.BLUE);
paint.setStrokeWidth(10);
paint.setStrokeCap(Paint.Cap.ROUND);
paint.setStrokeJoin(Paint.Join.ROUND);
draw();
}
public void surfaceDestroyed(SurfaceHolder holder) {
boolean retry = true;
thread.setRunning(false);
while (retry) {
try {
thread.join();
retry = false;
} catch (InterruptedException e) {
// we will try it again and again...
}
}
}
public void colorNew() {
// TODO Auto-generated method stub
paint.setColor(Color.GRAY);
}
}