Question

我画了一条从A点（始终为零）开始并在B点结束的行 canvas.drawLine（xStart，yStart，xEnd，yEnd）;

但是B点是可拖动的，所以我想在拖动时将画布线xEnd和yEnd更新为B位置。问题在于，当我更新线路编码时，只需1行解释就会出现错误：

“致命信号11（SIGSEGV），代码1，故障地址0x10c in tid 5638（xample.launcher）”它说xample.launcher但我的packageName是com.example.launcher，我不知道问题是否存在

这是我的代码。

DrawView（B点）

import android.app.Activity;
import android.view.View;

public class DrawView {

String label;
int color, direction, x, y;
View view;
DrawPath path;

public DrawView(){

}

public DrawView(String label, int color, int direction, int x, int y, View view){
    this.label = label;
    this.color = color;
    this.direction = direction;
    this.x = x;
    this.y = y;
    this.view = view;
}

public String getLabel() {
    return label;
}

public void setLabel(String label) {
    this.label = label;
}

public int getColor() {
    return color;
}

public void setColor(int color) {
    this.color = color;
}

public int getDirection() {
    return direction;
}

public void setDirection(int direction) {
    this.direction = direction;
}

public int getX() {
    return x;
}

public void setX(int x) {
    this.x = x;
}

public int getY() {
    return y;
}

public void setY(int y) {
    this.y = y;
}
public View getView() {
    return view;
}
public void setView(View view) {
    this.view = view;
}
public DrawPath getPath() {
    return path;
}
public void setPath(DrawPath path) {
    this.path = path;
}



}

DrawPath（A点到B点之间的线）

    package com.example.launcher;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.util.Log;
import android.view.View;

    public class DrawPath extends View{

    int color, x, y;
    Canvas canvas;
    Paint paint;

    public DrawPath(Context context) {
        super(context);
        // TODO Auto-generated constructor stub
    }

    @Override
    protected void onDraw(Canvas canvas) {
        // TODO Auto-generated method stub
        super.onDraw(canvas);
        this.canvas = canvas;
        paint = new Paint();
        paint.setColor(color);
        paint.setStrokeWidth(10);

        Log.e("THIS X, THIS Y", this.x + " " + this.y);
        canvas.drawLine(0, 0, this.x, this.y, paint);
        invalidate();
    }


    public void setColor(int color){
        this.color = color;
    }

    public int getColor(){
        return this.color;
    }

    public void setXValue(int x){
        this.x = x;
        if(canvas != null){
            canvas.drawLine(0, 0, this.x, this.y, paint);
            invalidate();
        }
    }

    public float getXValue(){
        return this.x;
    }

    public void setYValue(int y){
        this.y = y;
        if(canvas != null){
            canvas.drawLine(0, 0, this.x, this.y, paint);
            invalidate();
        }

    }

    public float getYValue(){
        return this.y;
    }



    }

最后是我的onTouch活动

@Override
    public boolean onTouch(View v, MotionEvent event) {
        // TODO Auto-generated method stub

        RelativeLayout.LayoutParams params = (RelativeLayout.LayoutParams)myView.getLayoutParams();
        final int X = (int)event.getRawX();
        final int Y = (int)event.getRawY();


        switch(event.getAction()){
            case MotionEvent.ACTION_DOWN:
                xDelta = X - (draw.getX());
                yDelta = Y - (draw.getY());
                break;
            case MotionEvent.ACTION_MOVE:   

                params.setMargins((X - xDelta), (Y - yDelta), 0, 0);
                draw.getPath().setXValue((X - xDelta));
                draw.getPath().setYValue((Y - yDelta));
                myView.setLayoutParams(params); 


                break;
            }

        return true;
    }

Android Canvas更新线coords

0 个答案: