我尝试在表面上显示相机预览。但它只显示黑色表面。我应该怎么办 ？我把代码放在下面 感谢您的帮助
import android.graphics.PixelFormat;
import android.hardware.Camera;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import java.io.IOException;
public class MainActivity extends ActionBarActivity implements SurfaceHolder.Callback {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
getWindow().setFormat(PixelFormat.UNKNOWN);
SurfaceView surfaceView = (SurfaceView) findViewById(R.id.surfaceView);
SurfaceHolder surfaceHolder = surfaceView.getHolder();
surfaceHolder.addCallback(this);
surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
Camera camera = Camera.open();
try {
camera.setPreviewDisplay(surfaceHolder);
camera.startPreview();
} catch (IOException e) {
e.printStackTrace();
}
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
}
}
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivity">
<SurfaceView
android:id="@+id/surfaceView"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</RelativeLayout>
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="test.frontcamerateststartup" >
<uses-permission android:name="android.permission.CAMERA"/>
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
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最佳答案
将以下代码放入surfaceCreated()
try {
camera.setPreviewDisplay(surfaceHolder);
camera.startPreview();
} catch (IOException e) {
e.printStackTrace();
}
表面需要在使用前设置
关于android - 为什么相机预览不起作用，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/29488481/