Android 手电筒源代码

近期因为公司须要，做了一个手电筒，事实上手电筒原理非常easy，就是调用照相机的闪光灯，控制闪光灯的开关，就能够实现手电筒的效果，

强调一下，代码中一定要注意在结束的时候对闪光灯进行释放，否则就会导致使用照相机的时候出现——无法连接到相机 这个问题

手电筒APK下载地址：点击打开下载链接

手电筒项目源代码下载：点击打开下载链接

主要代码例如以下：

package com.techainsh.flashlight;

import java.util.List;

import android.hardware.Camera;

import android.hardware.Camera.Parameters;

import android.os.Bundle;

import android.os.Handler;

import android.os.Looper;

import android.os.Message;

import android.os.PowerManager;

import android.os.Vibrator;

import android.app.Activity;

import android.content.Context;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.ImageView;

import android.widget.RelativeLayout;

import android.widget.Toast;

public class MainActivity extends Activity implements OnClickListener {

	public ImageView btnimageView = null;

	public RelativeLayout bgmageView = null;

	private Camera camera;

	private boolean isOpen = true;

	public final static int OPEN_CAMERA = 1011;

	public final static int OPEN_LIGHT = 1012;

	public final static int CLOSE_LIGHT = 1013;

	private Vibrator vibrator;

	long[] pattern = { 100, 200 };

	PowerManager.WakeLock wakeLock;

	@Override

	protected void onCreate(Bundle savedInstanceState) {

		super.onCreate(savedInstanceState);

		setContentView(R.layout.activity_main);

		handler.sendEmptyMessage(OPEN_CAMERA);

		vibrator = (Vibrator) getSystemService(Context.VIBRATOR_SERVICE);

		btnimageView = (ImageView) findViewById(R.id.btn_image);

		bgmageView = (RelativeLayout) findViewById(R.id.bg_image);

		bgmageView.setBackgroundResource(R.drawable.bg_flashlight_off);

		btnimageView.setImageResource(R.drawable.btn_flash_light_off);

		btnimageView.setOnClickListener(this);

		bgmageView.setBackgroundResource(R.drawable.bg_flashlight_on);

		btnimageView.setImageResource(R.drawable.btn_flash_light_on);

		handler.sendEmptyMessage(OPEN_LIGHT);

		vibrator.vibrate(pattern, -1);

	}

	Handler handler = new Handler(Looper.getMainLooper()) {

		@Override

		public void handleMessage(Message msg) {

			switch (msg.what) {

			case OPEN_CAMERA:

				camera = Camera.open();

				break;

			case OPEN_LIGHT:

				Parameters params = camera.getParameters();

				List<String> list = params.getSupportedFlashModes();

				if (list.contains(Parameters.FLASH_MODE_TORCH)) {

					params.setFlashMode(Parameters.FLASH_MODE_TORCH);

				} else {

					Toast.makeText(getApplicationContext(), "此设备不支持闪光灯模式",

							Toast.LENGTH_SHORT).show();

				}

				camera.setParameters(params);

				camera.startPreview();

				isOpen = true;

				break;

			case CLOSE_LIGHT:

				if (isOpen) {

					Parameters closepParameters = camera.getParameters();

					closepParameters

							.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);

					camera.setParameters(closepParameters);

					camera.stopPreview();

					// camera.release();

					isOpen = false;

					// sendEmptyMessage(OPEN_CAMERA);

				}

				break;

			default:

				break;

			}

		}

	};

	@Override

	protected void onDestroy() {

		super.onDestroy();

		if (null != camera) {

			camera.release();

			camera = null;

		}

	}

	public void onStop() {

		super.onStop();

		vibrator.cancel();

		if (null != camera) {

			camera.release();

			camera = null;

		}

		MainActivity.this.finish();

	}

	@Override

	protected void onResume() {

		// TODO Auto-generated method stub

		super.onResume();

		PowerManager pm = (PowerManager) getSystemService(POWER_SERVICE);

		wakeLock = pm.newWakeLock(PowerManager.SCREEN_BRIGHT_WAKE_LOCK

				| PowerManager.ON_AFTER_RELEASE, "test");

		wakeLock.acquire();

	}

	@Override

	protected void onPause() {

		// TODO Auto-generated method stub

		super.onPause();

		if (wakeLock != null)

			wakeLock.release();

	}

	@Override

	public void onClick(View v) {

		switch (v.getId()) {

		case R.id.btn_image:

			if (isOpen) {

				bgmageView.setBackgroundResource(R.drawable.bg_flashlight_off);

				btnimageView.setImageResource(R.drawable.btn_flash_light_off);

				handler.sendEmptyMessage(CLOSE_LIGHT);

				vibrator.vibrate(pattern, -1);

			} else {

				bgmageView.setBackgroundResource(R.drawable.bg_flashlight_on);

				btnimageView.setImageResource(R.drawable.btn_flash_light_on);

				handler.sendEmptyMessage(OPEN_LIGHT);

				vibrator.vibrate(pattern, -1);

			}

			break;

		default:

			break;

		}

	}

}

须要用到的权限例如以下：

 <uses-permission android:name="android.permission.CAMERA" />

    <uses-permission android:name="android.permission.FLASHLIGHT" />

    <uses-feature android:name="android.hardware.camera" />

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

    <uses-feature android:name="android.hardware.camera.flash" />

    <uses-permission android:name="android.permission.VIBRATE" />

    <uses-permission android:name="android.permission.WAKE_LOCK" /> 

界面布局例如以下：

<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:background="@drawable/bg_flashlight" >

    <RelativeLayout

        android:id="@+id/bg_image"

        android:layout_width="match_parent"

        android:layout_height="match_parent"

        android:background="@drawable/bg_flashlight_off" >

        <ImageView

            android:id="@+id/btn_image"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

           android:layout_centerHorizontal="true"

             android:layout_alignParentBottom="true"

             android:layout_marginBottom="100dip"

            android:src="@drawable/btn_flash_light_on" />

    </RelativeLayout>

</RelativeLayout>

实现的效果例如以下：