閃光燈的使用---製作手電筒

項目Demo地址:http://download.csdn.net/detail/hello_12413/8748065

編碼方式:UTF-8

記得當時從網上下的，看着簡介說沒廣告，然後忘了爲什麼自己很不爽，然後反編譯了，取了資源，自己寫一個。

效果圖如下：

權限不能忘了：

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

代碼很少，如下所示：

package com.example.flashlight;

import android.app.Activity;
import android.hardware.Camera;
import android.hardware.Camera.Parameters;
import android.os.Bundle;
import android.view.View;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.CompoundButton.OnCheckedChangeListener;
import android.widget.ImageView;
import android.widget.Toast;

public class MainActivity extends Activity implements OnCheckedChangeListener {
	private Camera mCamera;
	private Camera.Parameters parameters;
	private ImageView imageView1;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		((CheckBox) findViewById(R.id.checkBox1)).setOnCheckedChangeListener(this);
		imageView1 = (ImageView)findViewById(R.id.imageView1);
		imageView1.setVisibility(View.INVISIBLE);
		mCamera = Camera.open();
		parameters = mCamera.getParameters();
	}

	private void openLight() {
		parameters.setFlashMode(Parameters.FLASH_MODE_TORCH);
		mCamera.setParameters(parameters);
		mCamera.startPreview();
	}

	private void closeLight() {
		parameters.setFlashMode(Parameters.FLASH_MODE_OFF);
		mCamera.setParameters(parameters);
	}

	@Override
	public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
		if (isChecked) {
			imageView1.setVisibility(View.VISIBLE);
			openLight();
		} else {
			imageView1.setVisibility(View.INVISIBLE);
			closeLight();
		}
	}

	private long exitTime = 0;

	@Override
	public void onBackPressed() {
		long times = System.currentTimeMillis();
		if ((times - exitTime) > 2000) {
			Toast.makeText(getApplicationContext(), "再點擊一次退出應用", Toast.LENGTH_SHORT).show();
			exitTime = System.currentTimeMillis();
		} else {
			super.onBackPressed();
			finish();
			System.exit(0);
		}
	}

	@Override
	protected void onDestroy() {
		super.onDestroy();
		closeLight();
	}

}