如何绘制位图的部分通过Canvas DrawBitmap [英] How to Draw Portion of Bitmap via Canvas DrawBitmap
问题描述
我有
:
I have an
:
- FrameLayout红色)
- 源ImageView(黑色)
- 带有OnTouchListener(橙色)的对象(imageview)
通过对象与OnTouchListener,我想显示位图的一部分,填充在imageview(源imageview )。
Via Object with OnTouchListener,i want to show a portion of bitmap,that are filled on imageview(source imageview).
所以这不是一个问题,我这样做:
Bitmap bt = Bitmap.createBitmap(sourceBitmap, event.getX(),event.getY(),250,250);
So it's not a problem,i'm doing like this:
Bitmap bt = Bitmap.createBitmap(sourceBitmap,event.getX(),event.getY(),250,250);
其中:
- SourceBitmap - 是添加到源ImageView的图片
- event.getX() / event.getY()是一个坐标,我开始绘制位图的一部分
- / strong>, 250 - 部分位图的大小(部分)。
- SourceBitmap - is an image that are added to source ImageView
- event.getX() / event.getY() is an coord,where i start to draw portion of bitmap
- 250,250 - its an size of portion bitmap(part).
,结果是:
因此,当我的对象(带touchlistener)进入边框时,会出现问题(我已将橙色对象,与Object.width()/ 2)一起输出。
So the problems occurs,when my object(with touchlistener),going to the border(i have made this possibility for orange object,to go out of border with Object.width()/2).
所以在这种情况下:
如何实现结果:
其中结果为:
So in this case:
how can i achieve this result:
where result of portion will be:
- 部分位图
- 第二部分是framelayout背景的颜色。
$ b b
我现在尝试的:
What i tried at current moment:
public boolean onTouch(View view, MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_MOVE:
//i want to draw bigger portion then corrds
int CurrentX = (int)view.getX() - (view.getWidth());
int CurrentY = (int)view.getY() - (view.getHeight());
//case,when object is going out of border
if(CurrentX <= 0)
{
Paint paint = new Paint();
paint.setStyle( Style.FILL );
paint.setColor( Color.RED );
mBitmap = Bitmap.CreateBitmap(sourceBitmap,(int)view.getX() + Math.abs(CurrentX),(int)view.getY(),250,250);
Canvas canvas = new Canvas(mBitmap);
canvas.drawBitmap(mBitmap,new Rect((int)view.getX()+Math.abs(CurrentX), (int)view.getY(),250-Math.abs(CurrentX),250),new RectF(Math.abs(CurrentX), 0, 250,250),paint);
}
break;
}
return true;
}
}
有任何建议吗?感谢!
推荐答案
由自己解决!
< 复杂,但结果相当不错。
这里我们去:
case (当对象与OnTouchListener可以走出边界在X和Y轴),我已经邮政条件(某种法规)。
Solved by myself!
It was complicated,but result is pretty nice.
Here we go:
So for my case(when object with OnTouchListener can go out of border On X and Y axes),i've made Post Conditions(some kind of regulations).
宽度 = imageView 的宽度,其中我要显示结果。
高度 = imageView的高度显示结果;
Width = Width of imageView,where i want to show result.
Height = Height of imageView,where i want to show result;
- X_Coord ; 0 && Y_Coord - 高度/ 2 0&& Y_Coord Bitmap.Height
这是我们的顶部。 - X_Coord ; 0 && Y_Coord - 高度/ 2 > 0&& Y_Coord Bitmap.Height
这是我们的中区。 - X_Coord < 0 && Y_Coord - 高度/ 2 > 0&& Y_Coord > Bitmap.Height
这是我们的底部区域。
- X_Coord < 0 && Y_Coord - Height / 2 < 0 && Y_Coord < Bitmap.Height
This is our Top Area. - X_Coord < 0 && Y_Coord - Height / 2 > 0 && Y_Coord < Bitmap.Height
This is our Middle Area. - X_Coord < 0 && Y_Coord - Height / 2 > 0 && Y_Coord > Bitmap.Height
This is our Bottom Area.
RightSide
RightSide
- X_Coord > Bitmap.Height && Y_Coord - 高度/ 2 > 0&& Y_Coord Bitmap.Height
这是我们的中区。 - X_Coord > Bitmap.Height && Y_Coord - 高度/ 2 0&& Y_Coord Bitmap.Height
这是我们的顶部区域。 - X_Coord > Bitmap.Height && Y_Coord - 高度/ 2 > 0&& Y_Coord > Bitmap.Height
这是我们的底部区域。
- X_Coord > Bitmap.Height && Y_Coord - Height / 2 > 0 && Y_Coord < Bitmap.Height
This is our Middle Area. - X_Coord > Bitmap.Height && Y_Coord - Height / 2 < 0 && Y_Coord < Bitmap.Height
This is our Top Area. - X_Coord > Bitmap.Height && Y_Coord - Height / 2 > 0 && Y_Coord > Bitmap.Height
This is our Bottom Area.
标准(中间区域,不向左或右侧)
Standart(Area of Middle,that are not going to Left or Right side)
- X_Coord - 宽度/ 2 > 0 & X_Coord < Bitmap.Width &&& Y_Coord - 高度/ 2 0&& Y_Coord Bitmap.Height
这是我们的顶部区域。 - X_Coord - 宽度/ 2 > 0 & X_Coord < Bitmap.Width &&& Y_Coord - 高度/ 2 > 0&& Y_Coord > Bitmap.Height
这是我们的底部区域。 - X_Coord - 宽度/ 2 > 0 & X_Coord < Bitmap.Width &&& Y_Coord - 高度/ 2 > 0&& Y_Coord Bitmap.Height
这是我们的中区。
- X_Coord - Width / 2 > 0 && X_Coord < Bitmap.Width && Y_Coord - Height / 2 < 0 && Y_Coord < Bitmap.Height
This is our Top Area. - X_Coord - Width / 2 > 0 && X_Coord < Bitmap.Width && Y_Coord - Height / 2 > 0 && Y_Coord > Bitmap.Height
This is our Bottom Area. - X_Coord - Width / 2 > 0 && X_Coord < Bitmap.Width && Y_Coord - Height / 2 > 0 && Y_Coord < Bitmap.Height
This is our Middle Area.
所以通过这个条件,我在我的 MotionEvent.ACTION_MOVE $ c上绘制位图的一部分$ c> case。
让我们看一些例子:
So via this "Conditions",i'm drawing portion of bitmap on my MotionEvent.ACTION_MOVE
case.
Let's see some example:
public boolean onTouch(View view, MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_MOVE:
int Width = ResultImgView.getWidth();
int Height = ResultImgView.getHeight();
//paint for our Red background
Paint paint = new Paint();
paint.setStyle( Style.FILL );
paint.setColor( Color.RED );
Bitmap mBitmap = null;
Canvas canvas = null;
//Our Condition
if(view.getX() - Width / 2 >= SourceBitmap.getWidth()
&& view.getY() - Height / 2 > 0 && view.getY() + Height / 2 < SourceBitmap.getHeight())
{
//Nice,we entered here. Seems that we're now located at RightSide at Middle position
//So let's draw part of bitmap.
//our margin for X coords
int Difference = (int)((view.getX() - Width / 2 ) - SourceBitmap.getWidth();
//dont forget to put margin
//BTW we're now took portion of bitmap
mBitmap = Bitmap.createBitmap(SourceBitmap, ((int)view.getX() - Width / 2) - Difference, (int)view.getY() - Height / 2, Width,Height);
canvas = new Canvas(mBitmap);
//draw rect
canvas.drawRect(0,0,mBitmap.getWidth(),mBitmap.getHeight(),paint);
//draw portion of bitmap
canvas.drawBitmap(mBitmap,new Rect(Difference, 0,mBitmap.getWidth(),mBitmap.getHeight()),new Rect(0,0,mBitmap.getWidth() - Difference,mBitmap.getHeight()),null);
//and that's all!
}
//do the same for other condition....etc
break;
}
return true;
}
享受!
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