Paint画笔
public class PaintTest extends Activity{
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(new PaintView(this));
}
}
class PaintView extends SurfaceView implements Callback,Runnable{
private Thread mThread;
private Canvas mCanvas;
private boolean mFlag;
private Paint mPaint;
private SurfaceHolder mSurfaceHolder;
private Bitmap mBitmap;
public PaintView(Context context) {
super(context);
mSurfaceHolder=this.getHolder();
mSurfaceHolder.addCallback(this);
mPaint=new Paint();
mPaint.setColor(Color.WHITE);
mPaint.setAntiAlias(true);
mBitmap=BitmapFactory.decodeResource(getResources(), R.drawable.image);
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height) {
// TODO Auto-generated method stub
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
mFlag=true;
mThread=new Thread(this,"My Thread");
mThread.start();
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
mFlag=false;
}
@Override
public void run() {
while (mFlag) {
long start=System.currentTimeMillis();
myDraw();
logic();
long end=System.currentTimeMillis();
if ((end-start)<50) {
try {
Thread.sleep(50-(end-start));
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
private void logic() {
// TODO Auto-generated method stub
}
private void myDraw() {
try {
mCanvas=mSurfaceHolder.lockCanvas();
if (mCanvas != null) {
mCanvas.drawColor(Color.WHITE);
//Set brush no teeth
Paint paint=new Paint();
mCanvas.drawCircle(40, 30, 20, paint);
paint.setAntiAlias(true);
mCanvas.drawCircle(100, 30, 20, paint);
//Set the transparency of the brush
mCanvas.drawText("No Transparency", 130, 70, paint);
Paint paint2=new Paint();
paint2.setAlpha(0x77);
mCanvas.drawText("Semi-transparency", 20, 70, paint2);
//Set anchor to draw text
mCanvas.drawText("Anchor", 20, 90, new Paint());
Paint paint3=new Paint();
paint3.setTextAlign(Paint.Align.CENTER);
mCanvas.drawText("Anchor", 20, 105, paint3);
//Get text width
Paint paint4=new Paint();
float len=paint4.measureText("TextWidth");
mCanvas.drawText("TextWidth:"+len, 20, 130, paint4);
//Set paint style
mCanvas.drawRect(20, 140, 40, 160, new Paint());
Paint paint5=new Paint();
paint5.setStyle(Paint.Style.STROKE);//Set the brush does not fill
mCanvas.drawRect(60, 140, 80, 160, paint5);
//Set paint color
Paint paint6=new Paint();
paint6.setColor(Color.GRAY);
mCanvas.drawText("Gray", 20, 180, paint6);
//Set brush thickness
mCanvas.drawLine(20, 200, 70, 200, new Paint());
Paint paint7=new Paint();
paint7.setStrokeWidth(7);
mCanvas.drawLine(20, 220, 70, 220, paint7);
//Set text size
Paint paint8=new Paint();
paint8.setTextSize(20);
mCanvas.drawText("TextSize", 20, 260, paint8);
//Set the brush ARGB component
Paint paint9=new Paint();
paint9.setARGB(0x77, 0xff, 0x00, 0x00);
mCanvas.drawText("Translucent red", 20, 280, paint9);
}
} catch (Exception e) {
// TODO: handle exception
}finally{
if (mCanvas != null) {
mSurfaceHolder.unlockCanvasAndPost(mCanvas);
}
}
}
}
问题一：
paint9.setARGB(0x77, 0xff, 0x00, 0x00);
这是按照16进制换算的，ff表示最大，77表示一半，这个合起来表示:红色半透明 Translucent red