import android.graphics.drawable.Drawable;
import android.app.Activity;
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.os.Bundle;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;

import android.view.Window;
import android.view.WindowManager;
import android.widget.Button;

public class DrawBoard extends Activity {
	private Bitmap mBitmap;
	private MyView mView;
	private Button leave;
	private Button button;
	private Canvas mCanvas;

	public void onCreate(Bundle bundle) {
		super.onCreate(bundle);
		// remove the title, and display "full screen"
		this.requestWindowFeature(Window.FEATURE_NO_TITLE);
		this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
				WindowManager.LayoutParams.FLAG_FULLSCREEN);
		// get the windows resolution, for bitmap use
		DisplayMetrics dm = new DisplayMetrics();
		getWindowManager().getDefaultDisplay().getMetrics(dm);
		// create a new bitmap for paint

		mBitmap = Bitmap.createBitmap(351, 351, Bitmap.Config.ARGB_8888);
		// mBitmap=getResources().getDrawable(R.drawable.ab123);

		setContentView(R.layout.main);
		mView = new MyView(this);
		// ImageView iv = (ImageView) findViewById(R.id.imageView01);
		button = (Button) findViewById(R.id.button01);
		button.setOnClickListener(new Button.OnClickListener() {
			public void onClick(View v) {
				setContentView(mView);
			}
		});

		leave = (Button) findViewById(R.id.button02);
		leave.setOnClickListener(new Button.OnClickListener() {
			public void onClick(View v) {
				finish();
			}
		});

	}

	private class MyView extends View {

		private Path mPath;
		private Paint mBitmapPaint;
		private Paint mPaint, mPaint1;
		private float new_x, new_y;
		private float old_x, old_y;
		private Drawable PIC1;

		int px = getMeasuredWidth();
		int py = getMeasuredWidth();
		int pz = getWidth();
		DisplayMetrics dm = new DisplayMetrics();

		public MyView(Context context) {
			super(context);

			mCanvas = new Canvas(mBitmap);
			mPath = new Path();
			mBitmapPaint = new Paint(Paint.DITHER_FLAG);
			mPaint = new Paint();
			// mPaint1= new Paint();
			// mPaint1.setColor(Color.BLACK);
			// make paint more smooth
			mPaint.setAntiAlias(true);
			mPaint.setDither(true);
			// (1.FILL 2.FILL_AND_STROKE 3.STROKE)
			mPaint.setStyle(Paint.Style.STROKE);
			// (1.BEVEL 2.MITER 3.ROUND) default is MITER
			mPaint.setStrokeJoin(Paint.Join.ROUND);
			// (1.BUTT 2.ROUND 3.SQUARE) default is BUIT
			mPaint.setStrokeCap(Paint.Cap.ROUND);
			// if set "0", will be a line
			mPaint.setStrokeWidth(4);
			mPaint.setColor(Color.GREEN);
		}

		protected void onDraw(Canvas canvas) {
			/*
			 * getWindowManager().getDefaultDisplay().getMetrics(dm); int width
			 * = dm.widthPixels; int height = dm.heightPixels; PIC1 =
			 * this.getResources().getDrawable(R.drawable.test);
			 * PIC1.setBounds(0,351,351,height);
			 */
			// set background color

			canvas.drawColor(Color.WHITE);

			// canvas.drawLine(0, 0, 300, 300, mPaint);
			// draw the specified bitmap
			canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint);
			// the path will be filled or framed based on the Style in the paint
			canvas.drawPath(mPath, mPaint);
			// PIC1.draw(canvas);

		}

		public boolean onTouchEvent(MotionEvent event) {
			new_x = event.getX();
			new_y = event.getY();

			if (new_y > 351) {
			setContentView(R.layout.main);
			}
			if (event.getAction() == MotionEvent.ACTION_DOWN) {
				// save the previous path, then reset the path
				mPath.reset();
				// start position
				mPath.moveTo(new_x, new_y);
				old_x = new_x;
				old_y = new_y;
				mCanvas.save();
			} else if (event.getAction() == MotionEvent.ACTION_MOVE) {
				float dx = Math.abs(new_x - old_x);
				float dy = Math.abs(new_y - old_y);

				if (dx >= 4 || dy >= 4) {
					// set path from (old_x, old_y) to ((new_x + old_x)/2,
					// (new_y + old_y)/2)
					mPath.quadTo(old_x, old_y, (new_x + old_x) / 2,
							(new_y + old_y) / 2);
					old_x = new_x;
					old_y = new_y;
				}
			} else if (event.getAction() == MotionEvent.ACTION_UP) {
				// unknown, this line like no used
				mPath.lineTo(old_x, old_y);
				// paint the path when "ACTION_UP"

				mCanvas.drawPath(mPath, mPaint);
				// save the paint
				mPath.reset();
			}

			// update the paint, it will recall the onDraw function
			invalidate();
			return true;
		}
	}
}


//下面是XML設計
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <LinearLayout
        android:id="@+id/linearLayout1"
        android:layout_width="246dp"
        android:layout_height="wrap_content" >

        <Button
            android:id="@+id/button01"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="載入畫布" />

        <Button
            android:id="@+id/button02"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="finish" />
    </LinearLayout>

</LinearLayout>