Take a photo using camera

Android uses camera to control the photo taking. It is relatively simple to use camera, and you can proceed with the following steps:

The following is an example:

Activity:

Package COM. home. activity; import Java. io. file; import Java. io. fileoutputstream; import android. app. activity; import android. app. alertdialog; import android. content. context; import android. content. dialoginterface; import android. content. res. configuration; import android. graphics. bitmap; import android. graphics. bitmap. compressformat; import android. graphics. bitmapfactory; import android. graphics. pixelformat; Im Port android. hardware. camera; import android. hardware. camera. parameters; import android. hardware. camera. picturecallback; import android. OS. bundle; import android. OS. environment; import android. view. surfaceholder; import android. view. surfaceholder. callback; import android. view. surfaceview; import android. view. view; import android. view. view. onclicklistener; import android. view. window; import android. view. windo Wmanager; import android. widget. button; import android. widget. edittext; import android. widget. imageview; import COM. home. camera. r; public class testcameraactivity extends activity {private surfaceview sview; private surfaceholder sholder; // screen width and height private int screenwidth and screenheight; // define the camera private camera used by the system; // whether the camera is in preview status. true: preview status; false: Private Boolean ispreview; private button playbt N; @ overrideprotected void oncreate (bundle savedinstancestate) {super. oncreate (savedinstancestate); // sets the full screen requestwindowfeature (window. feature_no_title); getwindow (). setflags (windowmanager. layoutparams. flag_fullscreen, windowmanager. layoutparams. flag_fullscreen); setcontentview (R. layout. main); windowmanager WM = (windowmanager) getsystemservice (context. window_service); // obtain the screen width and height screenwidth = WM. getdefa Ultdisplay (). getwidth (); screenheight = WM. getdefadisplay display (). getheight (); playbtn = (button) findviewbyid (R. id. main_btn); // obtain the surfaceview component sview = (surfaceview) findviewbyid (R. id. main_sview); // obtain surfaceholdersholder = sview of surfaceview. getholder (); // Add a callback listener for sholder. addcallback (New callback () {@ overridepublic void surfacechanged (surfaceholder holder, int format, int width, int height) {}@ Overridepublic void surfacecreated (surfaceholder holder) {// enable and initialize the camera initcamera () ;}@ overridepublic void surfacedestroyed (surfaceholder holder) {// If camera is not null, release the camera if (camera! = NULL) {If (ispreview) {Camera. stoppreview (); camera. release (); camera = NULL ;}}}); // set the surfaceview itself to not maintain the buffer sholder. settype (surfaceholder. surface_type_push_buffers);}/*** initialize the camera */private void initcamera () {If (! Ispreview) {Camera = camera. open ();} If (camera! = NULL &&! Ispreview) {try {parameters = camera. getparameters (); // set the flashlight to the automatic status parameters. setflashmode (parameters. flash_mode_auto); camera. setparameters (parameters); // set the size of the previewed photo parameters. setpreviewsize (screenwidth, screenheight); // you can specify four parameters per second. setpreviewframerate (4); // sets the image format parameters. setpictureformat (pixelformat. JPEG); // set the quality of the JPG photo parameters. set ("Jpeg-quality", 85); // set the Photo size parameters. setpic Turesize (screenwidth, screenheight); // use surfaceview to display the camera image. setpreviewdisplay (sholder); // if it is a portrait screen if (this. getresources (). getconfiguration (). orientation! = Configuration. orientation_landscape) {Camera. setdisplayorientation (90);} else {Camera. setdisplayorientation (0);} // start previewing camera. startpreview (); // Auto Focus camera. autofocus (null); ispreview = true;} catch (exception e) {e. printstacktrace () ;}} playbtn. setonclicklistener (New onclicklistener () {@ overridepublic void onclick (view v) {If (camera! = NULL) {// take a photo of camera. takepicture (null, null, my‑callback) ;}}) ;}picturecallback my‑callback = new picturecallback () {@ overridepublic void onpicturetaken (final byte [] data, camera) {// create a bitmap final Bitmap bitmap = bitmapfactory based on the data obtained from the image. decodebytearray (data, 0, Data. length); // load save. view savedialog = getlayoutinflater (). inflate (R. layout. save, null); Final edittext photoname = (edittext) savedialog. findviewbyid (R. id. save_et_name); imageview showview = (imageview) savedialog. findviewbyid (R. id. save_image); // display the showview. setimagebitmap (Bitmap); // The savedialog component new alertdialog is displayed in the displayed dialog box. builder (testcameraactivity. this ). setview (savedialog ). setpositivebutton ("save", new dialoginterface. onclicklistener () {@ overridepublic void onclick (dialoginterface dialog, int which) {// create a file = new file (environment. getexternalstoragedirectory (), photoname. gettext (). tostring () + ". jpg "); fileoutputstream outstream = NULL; try {// open the output stream outstream of the specified file = new fileoutputstream (File); // output the bitmap to the specified file. compress (compressformat. JPEG, 100, outstream); outstream. close ();} catch (exception e) {e. printstacktrace ();}}}). setnegativebutton ("cancel", null ). show (); // preview camera again. stoppreview (); camera. startpreview (); ispreview = true ;}};}

The layout XML of the activity is a photo button and surfaceview component, which is omitted
Dialog Box layout XML:

<? XML version = "1.0" encoding = "UTF-8"?> <Linearlayout xmlns: Android = "http://schemas.android.com/apk/res/android" Android: layout_width = "match_parent" Android: layout_height = "match_parent" Android: Orientation = "vertical"> <linearlayout Android: layout_width = "match_parent" Android: layout_height = "wrap_content" Android: Orientation = "horizontal"> <textview Android: layout_width = "wrap_content" Android: layout_height = "wrap_content" Android: TEXT = "Enter the photo name"/> <edittext Android: Id = "@ + ID/save_et_name" Android: layout_width = "match_parent" Android: layout_height = "wrap_content" Android: layout_marginleft = "10dp" Android: singleline = "true"/> </linearlayout> <imageview Android: Id = "@ + ID/save_image" Android: layout_width = "wrap_content" Android: layout_height = "wrap_content"/> </linearlayout>

Add the following permissions:

<! -- Write permission to the external memory card --> <uses-Permission Android: Name = "android. Permission. write_external_storage"/> <! -- Add the photo permission --> <uses-Permission Android: Name = "android. Permission. Camera"/> <! -- Added the camera's additional functions --> <uses-feature Android: Name = "android. hardware. camera "/> <uses-feature Android: Name =" android. hardware. camera. autofocus "/> <! -- Add the flashlight permission --> <uses-Permission Android: Name = "android. Permission. Flashlight"/>

In addition, you can use the shortcut key on your mobile phone to call back the onkeydown () method.