package com.home.light;import android.app.Activity;import android.hardware.Camera;import android.hardware.Camera.Parameters;import android.os.Bundle;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import com.home.cameralight.R;public class TestActivity extends Activity implements OnClickListener {	Camera camera;	Parameters params;	private Button onBtn;	private Button offBtn;	@Override	protected void onCreate(Bundle savedInstanceState) {		super.onCreate(savedInstanceState);		setContentView(R.layout.main);		camera = Camera.open();		params = camera.getParameters();		findView();	}	private void findView() {		onBtn = (Button) findViewById(R.id.main_btn_on);		onBtn.setOnClickListener(this);		offBtn = (Button) findViewById(R.id.main_btn_off);		offBtn.setOnClickListener(this);	}	@Override	public void onClick(View v) {		if (v == onBtn) {//			open1();			open2();		} else if (v == offBtn) {//			off1();			off2();		}	}		private void open1() {		if (camera == null) {			camera = Camera.open();			params = camera.getParameters();		}		params.setFlashMode(Parameters.FLASH_MODE_TORCH);		camera.setParameters(params);	}	private void off1() {		if (camera == null) {			return;		}		params.setFlashMode(Parameters.FLASH_MODE_OFF);		camera.setParameters(params);		camera.release();		camera = null;	}	private void open2() {		if (camera == null) {			camera = Camera.open();			params = camera.getParameters();		}		params.setFlashMode(Camera.Parameters.FLASH_MODE_TORCH);		camera.setParameters(params);		camera.autoFocus(new Camera.AutoFocusCallback() {			public void onAutoFocus(boolean success, Camera camera) {			}		});		camera.startPreview();	}	private void off2() {		if (camera == null) {			return;		}		camera.stopPreview();		camera.release();		camera = null;	}}

权限：

    <uses-permission android:name="android.permission.FLASHLIGHT" />    <uses-permission android:name="android.permission.CAMERA" />    <uses-feature android:name="android.hardware.camera" />    <uses-feature android:name="android.hardware.autofocus"/>

使用照相机开启闪光灯