我正在使用 Surface View Camera 在 Android 中开发一个项目。我想在相机的 Surface View 上显示一些按钮和一个框架,并使其成为相机捕捉功能。
现在我完成了 SurfaceView 以查看相机上方的帧图像,但是当我添加按钮时,它显示在表面视图之外。下面是我的主要代码:
//这是我的PreviewDemo.java
package com.commonsware.android.camera;
import android.app.Activity;
import android.content.pm.ActivityInfo;
import android.hardware.Camera;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.ViewGroup.LayoutParams;
import android.widget.Toast;
public class PreviewDemo extends Activity {
private SurfaceView preview=null;
private SurfaceHolder previewHolder=null;
private Camera camera=null;
private boolean inPreview=false;
private boolean cameraConfigured=false;
LayoutInflater inflater = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
preview=(SurfaceView)findViewById(R.id.preview);
previewHolder=preview.getHolder();
previewHolder.addCallback(surfaceCallback);
previewHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
inflater = LayoutInflater.from(getBaseContext());
View view = inflater.inflate(R.layout.overlay, null);
LayoutParams layoutParamsControl= new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
this.addContentView(view, layoutParamsControl);
}
@Override
public void onResume() {
super.onResume();
camera=Camera.open();
startPreview();
}
@Override
public void onPause() {
if (inPreview) {
camera.stopPreview();
}
camera.release();
camera=null;
inPreview=false;
super.onPause();
}
private Camera.Size getBestPreviewSize(int width, int height,
Camera.Parameters parameters) {
Camera.Size result=null;
for (Camera.Size size : parameters.getSupportedPreviewSizes()) {
if (size.width<=width && size.height<=height) {
if (result==null) {
result=size;
}
else {
int resultArea=result.width*result.height;
int newArea=size.width*size.height;
if (newArea>resultArea) {
result=size;
}
}
}
}
return(result);
}
private void initPreview(int width, int height) {
if (camera!=null && previewHolder.getSurface()!=null) {
try {
camera.setPreviewDisplay(previewHolder);
}
catch (Throwable t) {
Log.e("PreviewDemo-surfaceCallback",
"Exception in setPreviewDisplay()", t);
Toast
.makeText(PreviewDemo.this, t.getMessage(), Toast.LENGTH_LONG)
.show();
}
if (!cameraConfigured) {
Camera.Parameters parameters=camera.getParameters();
Camera.Size size=getBestPreviewSize(width, height,
parameters);
if (size!=null) {
parameters.setPreviewSize(size.width, size.height);
camera.setParameters(parameters);
cameraConfigured=true;
}
}
}
}
private void startPreview() {
if (cameraConfigured && camera!=null) {
camera.startPreview();
inPreview=true;
}
}
SurfaceHolder.Callback surfaceCallback=new SurfaceHolder.Callback() {
public void surfaceCreated(SurfaceHolder holder) {
// no-op -- wait until surfaceChanged()
}
public void surfaceChanged(SurfaceHolder holder,
int format, int width,
int height) {
initPreview(width, height);
startPreview();
}
public void surfaceDestroyed(SurfaceHolder holder) {
// no-op
}
};
}
//这是我的Overlay.Xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_gravity="fill_vertical"
android:orientation="vertical" >
<SurfaceView
android:id="@+id/surface_camera"
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_gravity="center_horizontal"
android:layout_weight="1"
android:background="@drawable/frame"
android:clickable="true"
android:longClickable="false"
android:padding="@android:dimen/thumbnail_height" />
</LinearLayout>