我目前正在我的应用程序中绘制到屏幕上。用户可以绘制一个代表他们家的房间的矩形,但目前它们仅限于初始空间。
使屏幕简单地成为更大画布上的“窗口”的最佳方法是什么,用户可以在绘图时滚动、缩放等?(我很欣赏必须有一个“绘图”触摸模式和一个“移动”触摸模式)
此外,画布是一个自定义视图类:
class HomerView extends View { // the custom View for drawing on
// set up Bitmap, canvas, path and paint
private Bitmap myBitmap; // the initial image we turn into our canvas
private Canvas myCanvas; // the canvas we are drawing on
private Rect myRect; // the mathematical path of the lines we draw
private Paint myBitmapPaint; // the paint we use to draw the bitmap
// get the width of the entire tablet screen
private int screenWidth = getContext().getResources()
.getDisplayMetrics().widthPixels;
// get the height of the entire tablet screen
private int screenHeight = getContext().getResources()
.getDisplayMetrics().heightPixels;
public HomerView(Context context) { // constructor of HomerView
super(context);
myBitmap = Bitmap.createBitmap(screenWidth, screenHeight,
Bitmap.Config.ARGB_8888); // set our drawable space - the bitmap which becomes the canvas we draw on
myCanvas = new Canvas(myBitmap); // set our canvas to our bitmap which we just set up
myRect = new Rect(); // make a new rect
myBitmapPaint = new Paint(Paint.DITHER_FLAG); // set dither to ON in our saved drawing - gives better color interaction
}
protected void onDraw(Canvas canvas) { // method used when we want to draw something to our canvas
canvas.drawColor(Color.TRANSPARENT); // sets canvas colour
canvas.drawBitmap(myBitmap, 0, 0, myBitmapPaint); // save the canvas to bitmap - the numbers are the x, y coords we are drawing from
canvas.drawRect(myRect, myPaint); // draw the rectangle that the user has drawn using the paint we set up
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) { // if screen size changes, alter the bitmap size
super.onSizeChanged(w, h, oldw, oldh);
/*myBitmap = Bitmap.createBitmap(screenWidth, screenHeight,
Bitmap.Config.ARGB_8888);
myCanvas = new Canvas(myBitmap);*/
}
public void drawApplianceIcon() {
myCanvas.drawBitmap(bmp, iX - 50, iY - 50, myBitmapPaint);
makeToast("Lamp Drawn To Canvas");
}
// these variables are needed in touch listening
private int mX, mY, iX, iY; // current x,y and initial x,y
private static final float TOUCH_TOLERANCE = 4;
private void touch_start {} // touch methods
private void touch_move {}
private void touch_up {}
这在 onCreate 中声明如下:
View drawingAreaView = new HomerView(this);
setContentView(drawingAreaView);
如何调整我的代码以使其成为可滚动窗口?