Android Flashlight Implementation

Android phones have a lot of applications for flashlights, but some don't.

It was later discovered that the preview was opened in addition to setting the camera device's Flashmode to torch:

Here's the code:

Mainactivity.java

Package Com.android.flashlight;import Android.app.activity;import Android.os.bundle;import Android.view.motionevent;import Android.widget.imageview;public class Mainactivity extends Activity{private Flashlightsurface msurface;private ImageView mimageview;private Boolean Isflashlighton = false; @Overrideprotected void OnCreate (Bundle savedinstancestate) {super.oncreate (savedinstancestate); Setcontentview (R.layout.main); Contants.logi ("Mainactivity:oncreate ()"); msurface = (flashlightsurface) Findviewbyid (R.id.surfaceview); MImageView = (ImageView) Findviewbyid (r.id.image);} @Overridepublic boolean ontouchevent (Motionevent event) {if (motionevent.action_up = = Event.getaction ()) { Contants.logi ("Mainactivity:ontouchevent (): Action_up"), if (Isflashlighton) {Msurface.setflashlightswitch (false); Isflashlighton = False;mimageview.setimageresource (R.drawable.flashlight_off);} Else{msurface.setflashlightswitch (true); Isflashlighton = True;mimageview.setimageresource (R.drawable.flashlight_ on);}} Return SupeR.ontouchevent (event);}} 

Flashlightsurface.java

Package Com.android.flashlight;import Android.content.context;import Android.graphics.pixelformat;import Android.hardware.camera;import Android.util.attributeset;import Android.view.surfaceholder;import Android.view.surfaceview;public class Flashlightsurface extends Surfaceview implements surfaceholder.callback{ Private Surfaceholder mholder;private Camera mcameradevices;private camera.parameters mparameters;public Flashlightsurface (context context, AttributeSet Attrs) {Super (context, attrs); Contants.logi ("Flashlightsurface"); Mholder = This.getholder (); Mholder.addcallback (this); Mholder.settype ( Surfaceholder.surface_type_push_buffers);} @Overridepublic void Surfacechanged (surfaceholder holder, int format, int width,int height) {contants.logi (" Surfacechanged "); mparameters = Mcameradevices.getparameters (); if (mparameters! = null) Mparameters.setpictureformat ( PIXELFORMAT.JPEG); mparameters.setpreviewsize (480); Mparameters.setpicturesize (320, 480); Mcameradevices.setparameters (mparameters); MCAmeradevices.startpreview ();} @Overridepublic void surfacecreated (Surfaceholder holder) {contants.logi ("surfacecreated"); try {mcameradevices = Camera.open (); Mcameradevices.setpreviewdisplay (Mholder);} catch (Exception e) {if (mcameradevices! = null) mcameradevices.release (); mcameradevices = null;}} @Overridepublic void surfacedestroyed (Surfaceholder holder) {contants.logi ("surfacedestroyed"); if (mcameradevices = = NULL) Return;mcameradevices.stoppreview (); Mcameradevices.release (); mcameradevices = null;} /** * Set the switch status of the flashlight * @param on:true is turned on, false turns off */public void Setflashlightswitch (Boolean on) {if (mcameradevices = = null) r Eturn;if (mparameters = = null) {mparameters = Mcameradevices.getparameters ();} if (ON) {Mparameters.setflashmode (contants.flash_mode_torch);} Else{mparameters.setflashmode (Contants.flash_mode_off);} Contants.logi ("Setflashlightswitch-----------------" + on); Mcameradevices.setparameters (mparameters);}}

Layout file Main.xml

<?xml version= "1.0" encoding= "Utf-8"?> <relativelayout   xmlns:android= "http://schemas.android.com/apk /res/android "      android:layout_width=" fill_parent "      android:layout_height=" fill_parent ">    < Com.android.flashlight.FlashlightSurface        android:id= "@+id/surfaceview"        android:layout_width= "Fill_ Parent "      android:layout_height=" fill_parent "        ></com.android.flashlight.FlashlightSurface>    <imageview         android:id= "@+id/image"        android:layout_width= "fill_parent"      android:layout_height= " Fill_parent "    android:src=" @drawable/flashlight_off "    android:background=" #FFFFFFFF "        />    </RelativeLayout>

It was obvious that a preview had been opened, but the picture was covered and invisible. Otherwise the flash does not light.

There's a demo:http://download.csdn.net/detail/liu_zhen_wei/4801779 here.

Contains widgets form widgets usage and flashlight implementation, after installation, add the form widget (flashlight) to the desktop and then click on the widget to open the flashlight interface

Click on the interface to enable/disable the flashlight.