我有一些按钮的主要活动和一个带有画布的子视图。当我在按钮后面绘制某些内容时,如果我想在这些按钮之上绘制该怎么办?
acitvity_main.xml
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<com.name.www.app.MyImageView
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/image_view"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
<ImageButton
android:id="@+id/test_button"
android:layout_width="56dp"
android:layout_height="56dp"
android:background="@drawable/background"
android:src="@drawable/edit_reference"/>
</android.support.design.widget.CoordinatorLayout>
MyImageView.java
public class MyImageView extends android.support.v7.widget.AppCompatImageView {
public MyImageView(Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
init();
}
@Override
public boolean onTouchEvent(MotionEvent event) {
int action = event.getAction();
Pos.x = event.getX();
Pos.y = event.getY();
switch (action) {
case MotionEvent.ACTION_DOWN:
this.invalidate();
break;
case MotionEvent.ACTION_MOVE:
this.invalidate();
break;
default:
break;
}
return true;
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawCircle(Pos.x,Pos.y,100,mPaint);
}
}
图像按钮通常位于ImageView的顶部,但是如何使绘制圆环回到按钮的顶部?
这是因为自定义视图已添加到xml中的按钮之前:
尝试一下:
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ImageButton
android:id="@+id/test_button"
android:layout_width="56dp"
android:layout_height="56dp"
android:background="@drawable/background"
android:src="@drawable/edit_reference"/>
<com.name.www.app.MyImageView
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/image_view"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</android.support.design.widget.CoordinatorLayout>