Android 打开关闭闪光灯(里程碑2.1)

不同的手机，开启闪光灯的方法不一样，这里以摩托罗拉里程碑的手机为例

main.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >
    <Button
        android:id="@+id/open"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/open" />
    <Button
        android:id="@+id/close"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/close" />
</LinearLayout>

Activity代码：

package com.android.flashlight;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class AndroidFlashLightActivity extends Activity {
    /** Called when the activity is first created. */

    private Button mBtnOpen,mBtnClose;
    private MyFlashLight myFlashLight;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        mBtnOpen = (Button) findViewById(R.id.open);
        mBtnClose = (Button) findViewById(R.id.close);

        try {
            myFlashLight = new MyFlashLight();
        } catch (Exception e) {
            e.printStackTrace();
        }

        mBtnOpen.setOnClickListener(new Button.OnClickListener(){

            @Override
            public void onClick(View v) {
                if(myFlashLight.isEnabled() == false){
                    myFlashLight.enable(true);
                }
            }
        });

        mBtnClose.setOnClickListener(new Button.OnClickListener(){

            @Override
            public void onClick(View v) {
                if(myFlashLight.isEnabled() == true){
                    myFlashLight.enable(false);
                }
            }
        });
    }
}

封装的方法：

package com.android.flashlight;

import java.lang.reflect.Method;
import android.os.IBinder;

public class MyFlashLight {
    private Object svc = null;
    private Method getFlashlightEnabled = null;
    private Method setFlashlightEnabled = null;

    @SuppressWarnings("unchecked")
    public MyFlashLight() throws Exception{
        try {
            // call ServiceManager.getService("hardware") to get an IBinder for the service.
            // this appears to be totally undocumented and not exposed in the SDK whatsoever.
            Class sm = Class.forName("android.os.ServiceManager");
            Object hwBinder = sm.getMethod("getService", String.class).invoke(null, "hardware");

            // get the hardware service stub. this seems to just get us one step closer to the proxy
            Class hwsstub = Class.forName("android.os.IHardwareService$Stub");
            Method asInterface = hwsstub.getMethod("asInterface", android.os.IBinder.class);
            svc = asInterface.invoke(null, (IBinder) hwBinder);

            // grab the class (android.os.IHardwareService$Stub$Proxy) so we can reflect on its methods
            Class proxy = svc.getClass();

            // save methods
            getFlashlightEnabled = proxy.getMethod("getFlashlightEnabled");
            setFlashlightEnabled = proxy.getMethod("setFlashlightEnabled", boolean.class);
        }
        catch(Exception e) {
            throw new Exception("LED could not be initialized");
        }
    }

    public boolean isEnabled() {
        try {
            return getFlashlightEnabled.invoke(svc).equals(true);
        }
        catch(Exception e) {
            return false;
        }
    }

    public void enable(boolean tf) {
        try {
            setFlashlightEnabled.invoke(svc, tf);
        }
        catch(Exception e) {}
    }
}