Android绘图实现

package com.demo.android.helloactivity; import android.content.Context; import android.graphics.Bitmap; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Matrix; import android.graphics.Paint; import android.graphics.Path; import android.graphics.RectF; import android.graphics.Bitmap.Config; import android.graphics.Path.Direction; import android.util.AttributeSet; import android.view.View; public class CreateBitmap extends View { private Bitmap bitmap = null; private static final String drawContent = "Android画bitmap，显示文字内容。"; private Paint mPaint; public CreateBitmap(Context context, AttributeSet attrs){ super(context,attrs); mPaint = new Paint(); } public CreateBitmap(Context context, AttributeSet arrts, int defStyle){ super(context,arrts,defStyle); mPaint = new Paint(); } public boolean initCreateBitmap(int w, int h, int color){ bitmap = Bitmap.createBitmap(w, h, Config.ARGB_8888); Canvas canvas = new Canvas(bitmap); canvas.drawColor(Color.WHITE); Paint p = new Paint(); p.setColor(Color.BLUE); p.setTextSize(22); //canvas.drawText(drawContent, 0, 100, p); Paint cPaint = new Paint(); cPaint.setColor(Color.YELLOW); Path path = new Path(); path.addOval(new RectF(20,20,300,200), Direction.CW); canvas.drawPath(path, cPaint); canvas.drawTextOnPath( "Android开发有一段日子了，感觉是基础太差，所以现在是付出和付利息的时候了", path, 0, 22, p); return true; } @Override public void onDraw(Canvas canvas){ Matrix matrix = new Matrix(); //matrix.setRotate(degrees, px, py) //canvas.drawBitmap(bitmap, matrix, mPaint); canvas.drawBitmap(bitmap, 0, 0, mPaint); } }