Android中编写简单的手电筒小应用的实例教程
作者：剑萧舞蝶
这篇文章主要介绍了Android中编写简单的手电筒小应用的实例教程,简单粗暴地控制手机闪光灯的开闭,效果拔群XD 需要的朋友可以参考下
主要实现两个步骤：
1、实现打开和关闭闪光灯；而实现操作闪光灯主要通过Camera类
Camera camera = Camera.open(); Parameters mParameters = camera.getParameters(); mParameters.setFlashMode(Camera.Parameters.FLASH_MODE_TORCH);//打开Camera.Parameters.FLASH_MODE_OFF
则为关闭
amera.setParameters(mParameters)
2、自定义闪光灯的按钮；自定义控件主要是设置设置view的大小
onMeasure(int widthMeasureSpec, int heightMeasureSpec)
效果如下：
源码如下：
<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:gravity="center"
android:background="@drawable/light"
tools:context=".MainActivity" >
<com.android.xiong.xionglight.LightBkView
android:id="@+id/light1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</RelativeLayout>
<uses-permission android:name="android.permission.CAMERA" />
package com.android.xiong.xionglight;
import android.app.Activity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.Menu;
public class MainActivity extends Activity {
private LightBkView light1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
light1 = (LightBkView) findViewById(R.id.light1);
//定义单击事件
light1.setOnClickListener(light1);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
package com.android.xiong.xionglight;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.hardware.Camera;
import android.hardware.Camera.Parameters;
import android.util.AttributeSet;
import android.view.View;
import android.view.View.OnClickListener;
public class LightBkView extends View implements OnClickListener {
Camera camera = Camera.open();
// 定义画皮
Paint paint = new Paint();
Paint paint1 = new Paint();
int x = 0;
int y = 0;
// 打开闪光灯
boolean islight;
public LightBkView(Context context, AttributeSet set) {
super(context, set);
}
@Override
protected void onDraw(Canvas canvas) {
// 获取控件的宽度和高度
int width = this.getWidth();
int heigth = this.getHeight();
// 圆点的坐标
x = width / 2;
y = heigth / 2;
//更换开关背景
if(!islight){
paint.setColor(Color.BLUE);
canvas.drawCircle(x, y, 60, paint);
paint1.setColor(Color.RED);
paint1.setTextSize(20);
canvas.drawText("打开闪光灯", x-50, y, paint1);
invalidate();
}else{
paint.setColor(Color.WHITE);
canvas.drawCircle(x, y, 60, paint);
paint1.setColor(Color.RED);
paint1.setTextSize(20);
canvas.drawText("关闭闪光灯", x-50, y, paint1);
invalidate();
}
}
// 定义View的大小
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
setMeasuredDimension(getWidth(widthMeasureSpec),
getHeight(heightMeasureSpec));
}
//定义view的宽度
public int getWidth(int widthMeasureSpec) {
int reslut = 0;
int widthMode = MeasureSpec.getMode(widthMeasureSpec);
if (widthMode == MeasureSpec.AT_MOST) {
reslut = 120;
}
if (widthMode == MeasureSpec.EXACTLY) {
reslut = MeasureSpec.getSize(widthMeasureSpec);
}
return reslut;
}
//定义view的高度
public int getHeight(int heightMeasureSpec) {
int reslut = 0;
int heightMode = MeasureSpec.getMode(heightMeasureSpec);
if (heightMode == MeasureSpec.AT_MOST) {
reslut = 120;
}
if (heightMode == MeasureSpec.EXACTLY) {
reslut = MeasureSpec.getSize(heightMeasureSpec);
}
return reslut;
}
// 实现闪光灯的的开关
@Override
public void onClick(View v) {
if (!islight) {
Parameters mParameters = camera.getParameters();
mParameters.setFlashMode(Camera.Parameters.FLASH_MODE_TORCH);
camera.setParameters(mParameters);
islight = true;
} else {
Parameters mParameters = camera.getParameters();
mParameters.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);
camera.setParameters(mParameters);
islight = false;
}
}
}