可以使用Android Studio中的Camera API来调用照相机。以下是调用照相机的步骤：
1. 在AndroidManifest.xml文件中添加相机权限：
```xml
<uses-permission android:name="android.permission.CAMERA" />
```
2. 在布局文件中添加一个按钮，用于触发照相机：
```xml
<Button
android:id="@+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Take a photo" />
```
3. 在Activity中添加以下代码：
```java
private static final int REQUEST_IMAGE_CAPTURE=1;
private Button mButton;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mButton=findViewById(R.id.button);
mButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
dispatchTakePictureIntent();
}
});
}
private void dispatchTakePictureIntent() {
Intent takePictureIntent=new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
if (takePictureIntent.resolveActivity(getPackageManager()) !=null) {
startActivityForResult(takePictureIntent, REQUEST_IMAGE_CAPTURE);
}
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode==REQUEST_IMAGE_CAPTURE && resultCode==RESULT_OK) {
Bundle extras=data.getExtras();
Bitmap imageBitmap=(Bitmap) extras.get("data");
// Do something with the imageBitmap
}
}
```
4. 运行应用程序并单击按钮以调用照相机。
