Android uses a camera to take photos

// Main. XML is as follows: <? 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"> <surfaceview Android: id = "@ + ID/surfaceview" Android: layout_width = "fill_parent" Android: layout_height = "fill_parent"/> </linearlayout> // mainactivity is as follows: Package COM. bravesoft; import Java. io. file; import Java. io. fileoutputstream; Im Port android. app. activity; import android. graphics. bitmap; import android. graphics. bitmap. compressformat; import android. graphics. bitmapfactory; import android. graphics. pixelformat; import android. hardware. camera; import android. hardware. camera. parameters; import android. hardware. camera. picturecallback; import android. OS. bundle; import android. OS. environment; import android. view. display; import android. view. Keyevent; import android. view. surfaceholder; import android. view. surfaceview; import android. view. window; import android. view. windowmanager;/*** pay attention to permissions ** <uses-Permission Android: Name = "android. permission. camera "/> <! -- Create and delete file permissions in sdcard --> <uses-Permission Android: Name = "android. Permission. mount_unmount_filesystems"/> <! -- Write data permission to sdcard --> <uses-Permission Android: Name = "android. permission. write_external_storage "/> * @ author administrator **/public class testcameraactivity extends activity {private surfaceview; private camera; private Boolean ispriview; @ overridepublic void oncreate (bundle privilege) {super. oncreate (savedinstancestate); // remove the title bar this. requestwindowfeature (window. feature_no_t Itle); // getwindow () is displayed on the full screen (). setflags (windowmanager. layoutparams. flag_fullscreen, windowmanager. layoutparams. flag_fullscreen); // setcontentview (R. layout. main); surfaceview = (surfaceview) findviewbyid (R. id. surfaceview); surfaceview. getholder (). settype (surfaceholder. surface_type_push_buffers); surfaceview. getholder (). setfixedsize (176,144); // sets the resolution surfaceview. getholder (). addcallback (New surfaceholder Callbackimpl (); // callback of surfaceview} class surfaceholdercallbackimpl implements surfaceholder. callback {@ overridepublic void surfacechanged (surfaceholder holder, int format, int width, int height) {}@ overridepublic void surfacecreated (surfaceholder holder) {windowmanager = (windowmanager) testcameraactivity. this. getsystemservice (window_service); display = windowmanager. getdefaultd Isplay (); camera = camera. open (); // open the camera parameters Params = camera. getparameters (); Params. setpreviewsize (display. getwidth (), display. getheight (); // sets the size of the previewed photo Params. setpreviewframerate (5); // number of photos captured by the camera per second. this is the Params of 5 images per second. setpictureformat (pixelformat. JPEG); // set the photo output format Params. set ("Jpeg-quality", 85); // sets the photo quality Params. setpicturesize (display. getwidth (), display. getheight (); // set the Photo size. Try {Camera. setparam Eters (Params); // sets the Camera Parameter camera. setpreviewdisplay (holder); // sets the surfaceviewcamera used by the camera. startpreview (); // enable the camera to preview ispriview = true;} catch (exception e) {e. printstacktrace () ;}@ overridepublic void surfacedestroyed (surfaceholder holder) {If (camera! = NULL) {If (ispriview) {// if you are previewing camera. stoppreview (); // stop preview ispriview = false;} camera. release (); // release the camera }}@ overridepublic Boolean onkeydown (INT keycode, keyevent event) {// override the method of activity if (camera! = NULL & event. getrepeatcount () = 0) {// event. the number of times the getrepeatcount () button is repeated. repeated times = 0, indicating that only one switch (keycode) {// case keyevent is clicked. keycode_search: // Search button // camera. autofocus (null); // auto focus. this is the auto focus callback method. it can be null // return true; Case keyevent. keycode_camera: // The photo key case keyevent. keycode_search: // search key. press these two keys to take a photo of camera. takepicture (null, new picturecallbackimpl (); // take a photo. call the takepicturecallback callback function to process the photo. Return true;} return Super. onkeydown (keycode, event);} class picturecallbackimpl implements picturecallback {// callback processing after photographing @ overridepublic void onpicturetaken (byte [] data, camera) {Bitmap bitmap = bitmapfactory. decodebytearray (data, 0, Data. length); file = new file (environment. getexternalstoragedirectory (), system. currenttimemillis () + ". jpg "); try {fileoutputstream outputstream = new fileoutputstream (File); bitmap. compress (compressformat. JPEG, 100, outputstream); // 100 is a lossless compression outputstream. close (); camera. startpreview (); // after taking the photo, the camera starts previewing again. otherwise, the screen does not move.} catch (exception e) {e. printstacktrace ();}}}}