将按钮添加到自定义视图
Add Button to Custom View
我已经尝试扩展 LinearLayout
而不是简单的 View
来添加按钮和 View
的工作子项,但我仍然没有得到任何输出。从概念上讲,我在某个地方错了。
public class TouchEventView extends LinearLayout {
private Paint paint = new Paint();
private Path path = new Path();
private ViewGroup viewGroup;
public TouchEventView(Context ctx) {
super(ctx);
//Button Code Starts Here
LinearLayout touch = new TouchEventView(ctx);
Button bt = new Button(ctx);
bt.setText("A Button");
bt.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT,LayoutParams.WRAP_CONTENT));
touch.addView(bt); //Button Not Working
paint.setAntiAlias(true);
paint.setColor(Color.BLACK);
paint.setStrokeJoin(Paint.Join.ROUND);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(5f);
this.setBackgroundColor(Color.WHITE);
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawPath(path,paint);
}
@Override
public boolean onTouchEvent(MotionEvent event) {
float xPos = event.getX();
float yPos = event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
path.moveTo(xPos,yPos);
return true;
case MotionEvent.ACTION_MOVE:
path.lineTo(xPos,yPos);
break;
case MotionEvent.ACTION_UP:
break;
default:
return false;
}
invalidate();
return true;
}
}
问题是您正在创建一个新的 TouchEventView
并将 Button
添加到那个 View
。相反,您应该将 Button
直接添加到当前的 View
。
如果您希望能够从 XML.
中获取任何属性,您还应该实现 LinearLayout
中的其他构造函数
public class TouchEventView extends LinearLayout {
public TouchEventView(Context context) {
this(context, null);
}
public TouchEventView(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public TouchEventView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init();
}
private void init() {
Button button = new Button(getContext());
button.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT));
addView(button);
}
}
我已经尝试扩展 LinearLayout
而不是简单的 View
来添加按钮和 View
的工作子项,但我仍然没有得到任何输出。从概念上讲,我在某个地方错了。
public class TouchEventView extends LinearLayout {
private Paint paint = new Paint();
private Path path = new Path();
private ViewGroup viewGroup;
public TouchEventView(Context ctx) {
super(ctx);
//Button Code Starts Here
LinearLayout touch = new TouchEventView(ctx);
Button bt = new Button(ctx);
bt.setText("A Button");
bt.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT,LayoutParams.WRAP_CONTENT));
touch.addView(bt); //Button Not Working
paint.setAntiAlias(true);
paint.setColor(Color.BLACK);
paint.setStrokeJoin(Paint.Join.ROUND);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(5f);
this.setBackgroundColor(Color.WHITE);
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawPath(path,paint);
}
@Override
public boolean onTouchEvent(MotionEvent event) {
float xPos = event.getX();
float yPos = event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
path.moveTo(xPos,yPos);
return true;
case MotionEvent.ACTION_MOVE:
path.lineTo(xPos,yPos);
break;
case MotionEvent.ACTION_UP:
break;
default:
return false;
}
invalidate();
return true;
}
}
问题是您正在创建一个新的 TouchEventView
并将 Button
添加到那个 View
。相反,您应该将 Button
直接添加到当前的 View
。
如果您希望能够从 XML.
中获取任何属性,您还应该实现LinearLayout
中的其他构造函数
public class TouchEventView extends LinearLayout {
public TouchEventView(Context context) {
this(context, null);
}
public TouchEventView(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public TouchEventView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init();
}
private void init() {
Button button = new Button(getContext());
button.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT));
addView(button);
}
}