Question

我有一个来自Activity类的对象：

 CustomPaint customCanvasPaint=(CustomPaint) dialog.findViewById(R.id.customCanvasPaint);

如何将此对象传递给类：

public class CustomPaint extends CanvasView {
  public CustomPaint(Context context) {
    super(context);
    initialize(context);
  }

  public CustomPaint(Context context, AttributeSet attrs) {
    super(context, attrs);
    initialize(context);
  }


  public void initialize(Context context){
    LayoutInflater inflater=(LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    View view=inflater.inflate(R.layout.custom_paint,null);
    CanvasView canvasView = (CanvasView) view.findViewById(R.id.customCanvasView);
    canvasView.setPaintStrokeColor(Color.RED);
    canvasView.setPaintStrokeWidth(12f);
  }
}

我想在初始化方法中自定义对象，但是绘制颜色和绘制宽度不会改变。我该怎么办？谢谢。

Answer 1

public class CustomPaint extends CanvasView {
 CanvasView mCanvasView;
 public CustomPaint(Context context,CanvasView canvasView) {
    super(context);
    this.mCanvasView = canvasView;
    initialize(context);
  }

  public CustomPaint(Context context, AttributeSet attrs,CanvasView canvasView) {
    super(context, attrs);
    this.mCanvasView = canvasView;
    initialize(context);
  }

public void initialize(Context context){

canvasView.setPaintStrokeColor(Color.RED);
canvasView.setPaintStrokeWidth(12f);
 }
  }

表单活动

 CanvasView canvasPaint=(CanvasView) dialog.findViewById(R.id.canvasPaint);
CustomPaint mCustomPaint = new CustomPaint(this,canvasPaint);

Answer 2

您可以在子类中进行必要的更改，并将此子类添加到.xml布局文件中。

 CustomPaint canvasPaint=(CustomPaint) dialog.findViewById(R.id.customPaint);

为了对此视图进行更改，您应该在传递画布上将onDraw()绘制方法覆盖到onDraw（）方法。看一下这个https://developer.android.com/training/custom-views/custom-drawing.html。

Answer 3

您可以通过在类中创建setter方法来传递对象：

这是你的活动：

@Override
protected void onCreate(Bundle bundle) {
   // 

   CustomPaint view = (CustomPaint) findViewById(R.id.customPaint);
   MyObject object = new MyObject("This is a test object");
   view.setData(object);
   view.postInvalidate();
}

从您的自定义类：

public CustomPaint extends View {
   private MyObject mData;

   //... Constructor and others ... 

   public void setData(MyObject data) {
      mData = data;
   }
}

将Activity对象传递给android

3 个答案: