如何创建一个surfaceview
时间: 2023-05-26 21:07:02 浏览: 58
要创建一个SurfaceView,需要以下步骤:
1. 在布局文件中添加SurfaceView:
```
<SurfaceView
android:id="@+id/surface_view"
android:layout_width="match_parent"
android:layout_height="match_parent" />
```
2. 在代码中获取SurfaceView:
```
SurfaceView surfaceView = findViewById(R.id.surface_view);
```
3. 实现SurfaceHolder.Callback接口,该接口是SurfaceView的接口回调函数,用于处理SurfaceView的创建、销毁、改变等事件:
```
class SurfaceViewCallback implements SurfaceHolder.Callback {
@Override
public void surfaceCreated(SurfaceHolder holder) {
// SurfaceView创建时调用
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
// SurfaceView改变时调用
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
// SurfaceView销毁时调用
}
}
```
4. 给SurfaceView添加Callback:
```
surfaceView.getHolder().addCallback(new SurfaceViewCallback());
```
5. 在SurfaceHolder.Callback的实现中,可以获取到SurfaceHolder对象,使用Canvas来绘制图形:
```
class SurfaceViewCallback implements SurfaceHolder.Callback {
@Override
public void surfaceCreated(SurfaceHolder holder) {
// SurfaceView创建时调用
Canvas canvas = holder.lockCanvas();
// 绘制图形
holder.unlockCanvasAndPost(canvas);
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
// SurfaceView改变时调用
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
// SurfaceView销毁时调用
}
}
```