对于Android编程来说,我仍然是一个不可思议的新手(比如3周大),但我慢慢得到了一些东西。我已经在不同的网站上寻找答案,但我还没有找到任何答案。
到目前为止我的Java代码(至少是相关的):
view = (ImageView)findViewById(R.id.imageView3);
backgroundImageName = String.valueOf(view.getTag());
view.setOnTouchListener(new View.OnTouchListener() {
public boolean onTouch(View v, MotionEvent event) {
int myNewX = (int)event.getX(); //this line and the next get the X & Y coordinates of wherever the mouse clicked
int myNewY = (int)event.getY();
Button button = (Button)findViewById(R.id.add_text);
// find a way to keep the button within the borders of the white square
if (event.getAction() == MotionEvent.ACTION_UP) { //checks if the mouse click was released
button.setVisibility(View.VISIBLE);
button.setX(myNewX - 160); //this line and the next set the coordinates of the button (plus the adjustment)
button.setY(myNewY + 70); //to make the button by above and in the middle of where the mouse clicked
}
else
{
button.setVisibility(View.INVISIBLE);
}
return true;
}
});
到目前为止和我的XML代码(至少是相关的):
<ImageView
android:id="@+id/imageView3"
android:layout_width="450dp"
android:layout_height="450dp"
android:layout_marginBottom="8dp"
android:layout_marginLeft="8dp"
android:layout_marginRight="8dp"
android:layout_marginTop="8dp"
android:contentDescription="@string/white_background"
android:tag="white"
android:visibility="invisible"
app:layout_constraintBottom_toBottomOf="@+id/button"
app:layout_constraintLeft_toLeftOf="@+id/imageView2"
app:layout_constraintRight_toRightOf="@+id/imageView2"
app:layout_constraintTop_toTopOf="@+id/textView"
app:srcCompat="@mipmap/white" />
<Button
android:id="@+id/add_text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/add_text"
android:visibility="invisible"
tools:ignore="MissingConstraints"
tools:layout_editor_absoluteY="71dp"
tools:layout_editor_absoluteX="16dp" />
我想要做的是将按钮保持在图片中显示的边界内,但我不知道该怎么做。我已经知道它应该如何工作:
If mouseclick (the event) is outside the border {
set the x coordinate of the button to the edge of the border
and the same for the y coordinate
}
我一直试图让它正常工作,但它只是拒绝。如果有人能帮我弄清楚我需要的代码,我会非常感谢你的帮助。
谢谢
答案 0 :(得分:1)
首先创建边界检查,然后执行任务:
<android.support.design.widget.TextInputLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<EditText
android:id="@+id/name_edit_text"
android:background="@drawable/edit_text_design"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="Name"/>
</android.support.design.widget.TextInputLayout>
});
注意:从API 14开始,您可以使用:Android MotionEvent&#39; ACTION_HOVER_ENTER: https://developer.android.com/reference/android/view/MotionEvent.html#ACTION_HOVER_ENTER