我的主类中有一个Bitmap对象.我需要将此位图发送到我的自定义视图类,以将其设置为在画布上进一步处理的背景.
例如,有一个名为setPicture的方法,它接收位图作为参数.那么,如何在画布上绘制这个位图呢？
请参阅以下代码：
public class TouchView extends View {
final int MIN_WIDTH = 75;
final int MIN_HEIGHT = 75;
final int DEFAULT_COLOR = Color.RED;
int _color;
final int STROKE_WIDTH = 2;
private Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
private float x,y;
private boolean touching = false;
public TouchView(Context context,AttributeSet attrs,int defStyle) {
super(context,attrs,defStyle);
// TODO Auto-generated constructor stub
init();
}
public TouchView(Context context,AttributeSet attrs) {
super(context,attrs);
// TODO Auto-generated constructor stub
init();
}
public TouchView(Context context) {
super(context);
// TODO Auto-generated constructor stub
init();
}
private void init() {
setMinimumWidth(MIN_WIDTH);
setMinimumHeight(MIN_HEIGHT);
_color = DEFAULT_COLOR;
}
@Override
protected void onMeasure(int widthMeasureSpec,int heightMeasureSpec) {
// TODO Auto-generated method stub
setMeasuredDimension(MeasureSpec.getSize(widthMeasureSpec),MeasureSpec.getSize(heightMeasureSpec));
}
@Override
protected void onDraw(Canvas canvas) {
// TODO Auto-generated method stub
super.onDraw(canvas);
if (touching) {
paint.setStrokeWidth(STROKE_WIDTH);
paint.setColor(_color);
paint.setStyle(Paint.Style.FILL);
canvas.drawCircle(x,y,75f,paint);
}
}
public void setPicture (Bitmap bitmap) {
///////
This method must receive my bitmap to draw it on canvas!!!!!!!!!!!!!!!
///////
}
public void setColor(int color) {
_color = color;
}
@Override
public boolean onTouchEvent(MotionEvent motionEvent) {
// TODO Auto-generated method stub
switch (motionEvent.getAction()) {
case MotionEvent.ACTION_MOVE:
case MotionEvent.ACTION_DOWN:
x = motionEvent.getX();
y = motionEvent.getY();
touching = true;
break;
default:
touching = false;
}
invalidate();
return true;
}
}
我应该如何将此位图发送到onDraw？
解决方法
在你的onDraw()方法里面,
做就是了
canvas.drawBitmap(myBitmap,null);
myBitmap是你的位图变量.
0,0指的是绘制的坐标,即左上角.
还有其他的Apis,可以吸引到某些地区等.
More info can be found here in the api docs.
或者：改为扩展ImageView,并使用setImageBitmap(Bitmap src);实现这一目标的方法.
