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How can i set onClickListener and onTouchListenere Both on View Class in android

How can i set onClickListener and onTouchListenere Both on View Class in android?
my code:
package com.example.circledemo.second;
import java.util.ArrayList;
import android.app.Dialog; import android.content.Context; import android.graphics.Bitmap; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.graphics.Path; import android.graphics.RectF; import android.view.MotionEvent; import android.view.View; import android.view.Window; import android.widget.ImageView; import android.widget.TextView;
import com.example.circledemo.R;
public class SecondTCanvas extends View {
public Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG); Context contextData; int layoutWidth, layoutHeight;
private Bitmap canvasBitmap;
public SecondTCanvas(Context context, float[] values, int width, int height) { super(context); contextData = context; layoutHeight = height; layoutWidth = width;
System.out.println("=== Layout .... Width : " + layoutWidth + " Height : " + layoutHeight); }
public void onDraw(Canvas c) {
paint.setColor(Color.BLACK); c.drawRect(0, 0, getWidth(), getHeight(), paint); buildDrawingCache(true); canvasBitmap = getDrawingCache(true); }
#Override public boolean onTouchEvent(MotionEvent event) { if (event.getAction() == MotionEvent.ACTION_DOWN) { // Get x and y coordinates of where the finger touched int pixelX = (int) (Math.floor(event.getX())); int pixelY = (int) (Math.floor(event.getY()));
if (canvasBitmap != null) { }
invalidate(); }
// If the finger is off the screen if (event.getAction() == MotionEvent.ACTION_UP) { // alphaIndex = -1; //This is a flag to reset the view alphas to // normal invalidate(); }
return true;
// return super.onTouchEvent(event); }
}

While using OnTouchListner use return False now you can handle the click in click listner.

draw arrows with Path in Android

I read the article on http://www.curious-creature.org/2013/12/21/android-recipe-4-path-tracing/
Trying to draw arrows with Path which mentioned in the article, but with the following code, I got the half arrow, I already read articles about how to draw arrows on android. This question is more about "what's wrong with the following code." Thanks in advance.
package com.example.linepractice;
import android.os.Bundle;
import android.app.Activity;
import android.view.LayoutInflater;
import android.widget.LinearLayout;
import android.widget.LinearLayout.LayoutParams;
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
PracticeLineView pl = new PracticeLineView(this);
LayoutInflater mInflater = LayoutInflater.from(this);
LinearLayout mainView = (LinearLayout) mInflater.inflate(R.layout.activity_main, null);
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
params.setMargins(120, 120, 120, 120);
pl.setLayoutParams(params);
mainView.addView(pl);
setContentView(mainView);
}
}
package com.example.linepractice;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Path;
import android.view.View;
public class PracticeLineView extends View {
private Paint mPaint;
public PracticeLineView(Context context) {
super(context);
mPaint = new Paint();
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.translate(getPaddingLeft(), getPaddingTop() - getPaddingBottom());
canvas.drawPath(makeArrow(140,140), mPaint);
}
private static Path makeArrow(float length, float height) {
Path p = new Path();
p.moveTo(-2.0f, -height / 2.0f);
p.lineTo(length, 0.0f);
p.lineTo(-2.0f, height / 2.0f);
p.lineTo(-2.0f, -height / 2.0f);
p.close();
return p;
}
}
pic:

private static Path makeArrow(float length, float height) {
Path p = new Path();
p.moveTo(-2.0f, 0.0f);
p.lineTo(length, height / 2.0f);
p.lineTo(-2.0f, height);
p.lineTo(-2.0f, 0.0f);
p.close();
return p;
}

SurfaceView showing blank white screen

I am trying to draw an oval to the screen but all I am getting is a blank white canvas. Not only am I unsure whether I am drawing the oval correctly, but also am getting nothing to the screen. Does anyone know why this is happening, I think the problem is that it isnt getting to the drawing section of the thread...
package hidden;
import android.app.Activity;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.PixelFormat;
import android.graphics.PorterDuff;
import android.graphics.RectF;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.shapes.OvalShape;
import android.os.Bundle;
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.view.View.OnTouchListener;
public class Surface extends Activity implements OnTouchListener
{
SurfaceView v;
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.activity_main);
setRequestedOrientation(1);
v = new SView(this);
v.setOnTouchListener(this);
v.setZOrderOnTop(true);
setContentView(v);
}
public class SView extends SurfaceView implements Runnable
{
Thread t1 = null;
SurfaceHolder holder;
boolean isItOk = false;
public SView(Context context)
{
super(context);
holder = getHolder();
holder.setFormat(PixelFormat.TRANSPARENT);
}
public void run()
{
while(isItOk)
{
if(!holder.getSurface().isValid())
{
continue;
}
Canvas c = holder.lockCanvas();
Paint p = new Paint();
p.setColor(Color.BLUE);
//OvalShape oval = new OvalShape();
//oval.draw(c, p);
Paint paint = new Paint();
paint.setColor(Color.GREEN);
paint.setStyle(Paint.Style.STROKE);
float leftx = 20;
float topy = 20;
float rightx = 50;
float bottomy = 100;
RectF ovalBounds = new RectF(leftx, topy, rightx, bottomy);
c.drawOval(ovalBounds, paint);
holder.unlockCanvasAndPost(c);
}
}
public void pause()
{
isItOk = false;
while(true)
{
try
{
t1.join();
}
catch(InterruptedException e)
{
e.printStackTrace();
}
break;
}
t1 = null;
}
public void resume()
{
isItOk = true;
t1 = new Thread(this);
t1.start();
}
}
public boolean onTouch(View arg0, MotionEvent arg1)
{
return false;
}
}

Increase speed to redraw the Android Screen

I am new to Android.My application requires to redraw a canvas circle over and over again. However, the speed of redraw is less than what I want. How may I increase the same.
My code is as follows:
--> ImagePracActivity.java
package com.pkg.ImagPrac;
import android.app.Activity;
import android.os.Bundle;
import android.view.Window;
import android.view.WindowManager;
public class ImagePracActivity extends Activity {
//DrawView drawView;
movement mv;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Set full screen view
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
requestWindowFeature(Window.FEATURE_NO_TITLE);
mv=new movement(getApplicationContext());
setContentView(mv);
mv.requestFocus();
}
}
--> movement.java
package com.pkg.ImagPrac;
import android.content.Context;
import android.content.Intent;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.util.Log;
import android.view.Display;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.view.WindowManager;
public class movement extends View implements OnTouchListener{
Display display;
float x=0,y=0;
Paint paint=new Paint();
private boolean flag;
public movement(Context context) {
super(context);
setFocusable(true);
setFocusableInTouchMode(true);
this.setOnTouchListener(this);
paint.setColor(Color.BLUE);
paint.setAntiAlias(true);
display = ((WindowManager)
context.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
x = 0;
y = display.getHeight();
}
#Override
protected void onDraw(Canvas canvas) {
if(x<(display.getWidth()/2))
{
canvas.drawCircle(x++, y--, 5, paint);
}
else if(x<(display.getWidth()))
{
canvas.drawCircle(x++, y++, 5, paint);
}
this.invalidate();
}
public boolean onTouch(View arg0, MotionEvent arg1) {
// TODO Auto-generated method stub
return false;
}
}

A would advice you to use SurfaceView class instead of View, because SurfaceView faster and allows you to have all drawing logic in separate thread. Read more about SurfaceView : http://developer.android.com/guide/topics/graphics/2d-graphics.html

try this
mPaint = new Paint();
mPaint.setAntiAlias(true);
mPaint.setDither(true);
mPaint.setColor(Color.BLUE);
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setStrokeJoin(Paint.Join.ROUND);
mPaint.setStrokeCap(Paint.Cap.ROUND);
mPaint.setStrokeWidth(5);

Android On Touch

I have been trying to make a program draw circles as I touch the screen with no luck, can anyone please tell me how I can do this? or GOOD tutorial that shows me how... I keep getting errors in my code
import android.content.Context;
import android.content.Intent;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.text.format.Time;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import java.lang.Math;
public class GameView extends View{
private final float x;
private final float y;
private final int r;
private final Paint mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
public GameView(Context context, float x, float y, int r) {
super(context);
setFocusable(true);
mPaint.setColor(0xFFFF0000);
this.x = x;
this.y = y;
this.r = r;
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawCircle(x, y, r, mPaint);
}
}
GameActivity.java
import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.Display;
import android.view.MotionEvent;
import android.view.View;
import android.view.WindowManager;
import android.widget.FrameLayout;
public class GameActivity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
FrameLayout main = (FrameLayout) findViewById(R.id.my_view);
main.setOnTouchListener(new View.OnTouchListener() {
public boolean onTouch(final View v, MotionEvent e) {
final float x = e.getX();
final float y = e.getY();
final Handler handler = new Handler()
{
public void handleMessage(Message msg) {
}
};
Thread graphicThread = new Thread()
{
public void run() {
try {
//Do the drop
FrameLayout flView = (FrameLayout) v;
GameView gm = new GameView(getParent(), x,y,25);
flView.addView(gm);
Thread.sleep(1000);
handler.sendMessage(handler.obtainMessage());
}
catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
};
boolean isRunning=true;
graphicThread.start();
return true;
}
});
}
}

You shouldn't be using getParent() in your activity if it's not a child Activity.
Use this instead:
GameView gm = new GameView(this, x, y, 25);

As the NPE question is already answered, I want to provide an answer for the tutorial question. I have written a series (which is partly updated) which you can find here: I have written a tutorial about 2d graphics for a game. Read this: http://www.droidnova.com/2d-tutorial-series