3

this is somewhat of of difficult to describe issue but I'll do my very best:

I am developing a an android app that uses a custom camera activity. In this camera activity I use create a surface view programmatically and set it to the framelayout (covers full screen) that was defined in the xml layout file.

My question now is, how can I add other elements to the frame layout? Only programmatically? I am asking because as of now I was only able to add other elements programmatically. Elements that i added in the xml layout didn't appear on screen. Is it possible that they are just behind the surface view that i add to the frame layout? If so, would it be possible to bring them to the front?

Thank you guys!

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2 回答 2

7

当然，您可以添加尽可能多的按钮和其他小部件FrameLayout。由于FrameLayout允许堆叠视图，您在 xml 文件中添加的组件现在位于您以编程方式添加的视图后面。以下是动态创建和添加小部件的方法：

// find your framelayout
frameLayout = (FrameLayout) findViewById(....);

// add these after setting up the camera view        

// create a new Button
Button button1 = new Button(this);

// set button text
button1.setText("....");

// set gravity for text within button
button1.setGravity(Gravity.....);

// set button background
button1.setBackground(getResources().getDrawable(R.drawable.....));

// set an OnClickListener for the button
button1.setOnClickListener(new OnClickListener() {....})

// declare and initialize LayoutParams for the framelayout
FrameLayout.LayoutParams params = new FrameLayout.LayoutParams(
            FrameLayout.LayoutParams.WRAP_CONTENT,
            FrameLayout.LayoutParams.WRAP_CONTENT);

// decide upon the positioning of the button //
// you will likely need to use the screen size to position the
// button anywhere other than the four corners
params.setMargins(.., .., .., ..);

// use static constants from the Gravity class
params.gravity = Gravity.CENTER_HORIZONTAL;

// add the view
fl1.addView(button2, params);

// create and add more widgets

....
....

编辑1：

您可以在这里使用一个技巧：

// Let's say you define an imageview in your layout xml file. Find it in code:
imageView1 = (ImageView) findViewById(....);

// Now you add your camera view.
.........

// Once you add your camera view to the framelayout, the imageview will be 
// behind the frame. Do the following:
framelayout.removeView(imageView1);
framelayout.addView(imageView1);

// That's it. imageView1 will be on top of the camera view, positioned the way
// you defined in xml file

发生这种情况是因为：

子视图在堆栈中绘制，最近添加的子视图在顶部（来自 FrameLayout 上的 android 资源页面）

于 2013-07-29T18:44:00.130 回答
0

http://developer.android.com/reference/android/widget/FrameLayout.html

“FameLayout 旨在阻止屏幕上的一个区域以显示单个项目。通常，应该使用 FrameLayout 来保存单个子视图，因为很难以一种可扩展到不同屏幕尺寸的方式来组织子视图，而无需孩子彼此重叠。但是，您可以将多个孩子添加到 FrameLayout 并通过使用 android:layout_gravity 属性为每个孩子分配重力来控制它们在 FrameLayout 中的位置。

于 2013-07-29T18:11:39.137 回答