{"id":1340,"date":"2010-06-21T13:30:21","date_gmt":"2010-06-21T11:30:21","guid":{"rendered":"http:\/\/blogs.wittwer.fr\/whiler\/?p=1340"},"modified":"2023-03-12T15:03:28","modified_gmt":"2023-03-12T14:03:28","slug":"qr_code","status":"publish","type":"post","link":"https:\/\/blogs.wittwer.fr\/whiler\/2010\/06\/21\/qr_code\/","title":{"rendered":"Cr\u00e9er des codes QR dynamiques dans une application Android"},"content":{"rendered":"

On voit de plus en plus des images comme celle-ci…
\n

<\/a><\/center><\/p>\n

… les codes QR<\/a> !<\/p>\n

Pour en g\u00e9n\u00e9rer, il existe de nombreuses solutions sur internet<\/a>…<\/p>\n

Afin d’optimiser ses applications Android<\/a>W<\/em><\/sup>, il vaudrait mieux avoir des images statiques afin de ne pas consommer de CPU sur les p\u00e9riph\u00e9riques o\u00f9 l’application est d\u00e9ploy\u00e9e… Cependant, on peut parfois avoir besoin d’en g\u00e9n\u00e9rer de fa\u00e7on dynamique…<\/p>\n

Je vous propose dans cet article, une solution assez simple qui fonctionne pour ajouter cette fonctionnalit\u00e9 \u00e0 vos applications.
\n<\/p>\n

Pour l’impl\u00e9menter, j’ai t\u00e9l\u00e9charg\u00e9 la solution Java de Kazuhiko Arase<\/a>, et je l’ai l\u00e9g\u00e8rement modifi\u00e9e pour qu’elle fonctionne avec le SDK d’Android<\/a> :
\nEntre autre, la fa\u00e7on de modifier les pixels<\/a> d’une image en m\u00e9moire<\/a>…<\/p>\n

Avant :<\/p>\n

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<\/div><\/td>
    public<\/span> BufferedImage<\/span><\/a> createImage(<\/span>int<\/span> cellSize, int<\/span> margin)<\/span> throws<\/span> IOException<\/span><\/a> {<\/span>
\n       
\n        int<\/span> imageSize =<\/span> getModuleCount(<\/span>)<\/span> *<\/span> cellSize +<\/span> margin *<\/span> 2<\/span>;<\/span>
\n
\n        BufferedImage<\/span><\/a> image =<\/span> new<\/span> BufferedImage<\/span><\/a>(<\/span>imageSize, imageSize, BufferedImage<\/span><\/a>.TYPE_INT_RGB<\/span>)<\/span>;<\/span>
\n
\n        for<\/span> (<\/span>int<\/span> y =<\/span> 0<\/span>;<\/span> y <<\/span> imageSize;<\/span> y++<\/span>)<\/span> {<\/span>
\n
\n            for<\/span> (<\/span>int<\/span> x =<\/span> 0<\/span>;<\/span> x <<\/span> imageSize;<\/span> x++<\/span>)<\/span> {<\/span>
\n
\n                if<\/span> (<\/span>margin <=<\/span> x &&<\/span> x <<\/span> imageSize -<\/span> margin
\n                        &&<\/span> margin <=<\/span> y &&<\/span> y <<\/span> imageSize -<\/span> margin)<\/span> {<\/span>
\n                           
\n                    int<\/span> col =<\/span> (<\/span>x -<\/span> margin)<\/span> \/<\/span> cellSize;<\/span>
\n                    int<\/span> row =<\/span> (<\/span>y -<\/span> margin)<\/span> \/<\/span> cellSize;<\/span>
\n   
\n                    if<\/span> (<\/span>isDark(<\/span>row, col)<\/span> )<\/span> {<\/span>
\n                        image.setRGB<\/span>(<\/span>x, y, 0x000000)<\/span>;<\/span>
\n                    }<\/span> else<\/span> {<\/span>
\n                        image.setRGB<\/span>(<\/span>x, y, 0xffffff)<\/span>;<\/span>
\n                    }<\/span>
\n
\n                }<\/span> else<\/span> {<\/span>
\n                    image.setRGB<\/span>(<\/span>x, y, 0xffffff)<\/span>;<\/span>
\n                }<\/span>
\n            }<\/span>
\n        }<\/span>
\n
\n        return<\/span> image;<\/span>
\n    }<\/span><\/div><\/td><\/tr><\/tbody><\/table><\/div>\n

Apr\u00e8s :<\/p>\n

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<\/div><\/td>
    public<\/span> Bitmap createImage(<\/span>int<\/span> cellSize, int<\/span> margin, int<\/span> cForeground, int<\/span> cBackground, int<\/span> cMargin)<\/span> throws<\/span> IOException<\/span><\/a> {<\/span>
\n        int<\/span> imageSize =<\/span> getModuleCount(<\/span>)<\/span> *<\/span> cellSize +<\/span> margin *<\/span> 2<\/span>;<\/span>
\n
\n        Bitmap image =<\/span> Bitmap.createBitmap<\/span>(<\/span>imageSize, imageSize, Bitmap.Config<\/span>.ARGB_8888<\/span>)<\/span>;<\/span>
\n
\n        for<\/span> (<\/span>int<\/span> y =<\/span> 0<\/span>;<\/span> y <<\/span> imageSize;<\/span> y++<\/span>)<\/span> {<\/span>
\n
\n            for<\/span> (<\/span>int<\/span> x =<\/span> 0<\/span>;<\/span> x <<\/span> imageSize;<\/span> x++<\/span>)<\/span> {<\/span>
\n
\n                if<\/span> (<\/span>margin <=<\/span> x &&<\/span> x <<\/span> imageSize -<\/span> margin
\n                        &&<\/span> margin <=<\/span> y &&<\/span> y <<\/span> imageSize -<\/span> margin)<\/span> {<\/span>
\n                           
\n                    int<\/span> col =<\/span> (<\/span>x -<\/span> margin)<\/span> \/<\/span> cellSize;<\/span>
\n                    int<\/span> row =<\/span> (<\/span>y -<\/span> margin)<\/span> \/<\/span> cellSize;<\/span>
\n   
\n                    if<\/span> (<\/span>isDark(<\/span>row, col)<\/span> )<\/span> {<\/span>
\n                      image.setPixel<\/span>(<\/span>x, y, cForeground)<\/span>;<\/span>
\n                    }<\/span> else<\/span> {<\/span>
\n                      image.setPixel<\/span>(<\/span>x, y, cBackground)<\/span>;<\/span>
\n                    }<\/span>
\n
\n                }<\/span> else<\/span> {<\/span>
\n                  image.setPixel<\/span>(<\/span>x, y, cMargin)<\/span>;<\/span>
\n                }<\/span>
\n            }<\/span>
\n        }<\/span>
\n        return<\/span> image;<\/span>
\n    }<\/span><\/div><\/td><\/tr><\/tbody><\/table><\/div>\n

Vous pouvez t\u00e9l\u00e9charger le code source depuis ce lien : Code source<\/a><\/p>\n

Sur la page suivante, je vais vous montrer comment l’utiliser pour faire une impl\u00e9mentation des plus simples…
\n
\nJe commence par cr\u00e9er un nouveau projet :
\n

\"Nouveau<\/a>

Nouveau projet Android<\/p><\/div>
\nPuis j’importe le code source du zip<\/a> dans ce projet :
\n

\"Importer<\/a>

Importer une archive<\/p><\/div>
\n

\"Archive<\/a>

Archive import\u00e9e<\/p><\/div>
\nLe projet contient ainsi les fichiers n\u00e9cessaires \u00e0 la g\u00e9n\u00e9ration des codes QR. Je vous invite \u00e0 lire le fichier readme.txt concernant les licences associ\u00e9es.
\n

\"Le<\/a>

Le projet est pr\u00eat<\/p><\/div>
\nJ’ajoute un composant dans la mise en page de l’application g\u00e9n\u00e9r\u00e9e par d\u00e9faut qui affichera mon code QR :
\n

\"Ajout<\/a>

Ajout d'un ImageButton<\/p><\/div>
\nJ’ajoute la cha\u00eene de caract\u00e8res qui contient le texte \u00e0 afficher dans le code QR, dans le cas pr\u00e9sent, une adresse Web :
\n

\"Ajout<\/a>

Ajout d'une ressource textuelle<\/p><\/div>
\nTout est pr\u00eat, il suffit d’appeler les m\u00e9thodes n\u00e9cessaires pour g\u00e9n\u00e9rer et afficher le code QR dans le composant pr\u00e9c\u00e9demment ajout\u00e9 :
\n

\"Code<\/a>

Code source<\/p><\/div><\/p>\n

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<\/div><\/td>
    public<\/span> void<\/span> onCreate(<\/span>Bundle savedInstanceState)<\/span> {<\/span>
\n        super<\/span>.onCreate<\/span>(<\/span>savedInstanceState)<\/span>;<\/span>
\n        setContentView(<\/span>R.layout<\/span>.main<\/span>)<\/span>;<\/span>
\n        imgBtnQR =<\/span> (<\/span>ImageButton)<\/span> findViewById(<\/span>R.id<\/span>.ImgBtnLink<\/span>)<\/span>;<\/span>
\n        try<\/span> {<\/span>
\n          \/\/ G\u00e9n\u00e8re les donn\u00e9es en fonction de ma ressource<\/span>
\n          QRCode qrc =<\/span> QRCode.getMinimumQRCode<\/span>(<\/span>getString(<\/span>R.string<\/span>.MonLien<\/span>)<\/span>, ErrorCorrectLevel.L<\/span>)<\/span>;<\/span>
\n          \/\/ D\u00e9finit la taille<\/span>
\n          int<\/span>[<\/span>]<\/span> iSizeMargin =<\/span> {<\/span>4<\/span>, 4<\/span>}<\/span>;<\/span>
\n          \/\/ G\u00e9n\u00e8re l'image du code QR<\/span>
\n          Bitmap bmp =<\/span> qrc.createImage<\/span>(<\/span>
\n              iSizeMargin[<\/span>0<\/span>]<\/span>, iSizeMargin[<\/span>1<\/span>]<\/span>,
\n              getResources(<\/span>)<\/span>.getColor<\/span>(<\/span>android.R<\/span>.color<\/span>.black<\/span>)<\/span>,
\n              getResources(<\/span>)<\/span>.getColor<\/span>(<\/span>android.R<\/span>.color<\/span>.white<\/span>)<\/span>)<\/span>;<\/span>
\n          \/\/ D\u00e9finit l'image dans la mise en page<\/span>
\n          imgBtnQR.setImageBitmap<\/span>(<\/span>bmp)<\/span>;<\/span>
\n        }<\/span> catch<\/span> (<\/span>Exception<\/span><\/a> e)<\/span> {<\/span>
\n          Log.w<\/span>(<\/span>"QRCodeError"<\/span>, e)<\/span>;<\/span>
\n        }<\/span>  
\n    }<\/span><\/div><\/td><\/tr><\/tbody><\/table><\/div>\n

Il ne reste plus qu’\u00e0 lancer l’\u00e9mulateur pour v\u00e9rifier le r\u00e9sultat :
\n

\"Test<\/a>

Test dans l'\u00e9mulateur<\/p><\/div><\/p>\n

Le code QR a \u00e9t\u00e9 effectivement\/correctement g\u00e9n\u00e9r\u00e9 ! \"(y)\" <\/p>\n","protected":false},"excerpt":{"rendered":"

On voit de plus en plus de codes QR !<\/p>\n

Pour en g\u00e9n\u00e9rer, il existe de nombreuses solutions sur internet\u2026<\/p>\n

Afin d\u2019optimiser ses applications Android, il vaudrait mieux avoir des images statiques afin de ne pas consommer de CPU sur les p\u00e9riph\u00e9riques o\u00f9 l\u2019application est d\u00e9ploy\u00e9e\u2026 Cependant, on peut parfois avoir besoin d\u2019en g\u00e9n\u00e9rer de fa\u00e7on dynamique\u2026<\/p>\n

Je vous propose dans cet article, une solution assez simple qui fonctionne pour ajouter cette fonctionnalit\u00e9 \u00e0 vos applications…<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_links_to":"","_links_to_target":""},"categories":[132],"tags":[158,27,108],"class_list":["post-1340","post","type-post","status-publish","format-standard","hentry","category-android","tag-android","tag-coloration-syntaxique","tag-script"],"_links":{"self":[{"href":"https:\/\/blogs.wittwer.fr\/whiler\/wp-json\/wp\/v2\/posts\/1340","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.wittwer.fr\/whiler\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.wittwer.fr\/whiler\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.wittwer.fr\/whiler\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.wittwer.fr\/whiler\/wp-json\/wp\/v2\/comments?post=1340"}],"version-history":[{"count":2,"href":"https:\/\/blogs.wittwer.fr\/whiler\/wp-json\/wp\/v2\/posts\/1340\/revisions"}],"predecessor-version":[{"id":6387,"href":"https:\/\/blogs.wittwer.fr\/whiler\/wp-json\/wp\/v2\/posts\/1340\/revisions\/6387"}],"wp:attachment":[{"href":"https:\/\/blogs.wittwer.fr\/whiler\/wp-json\/wp\/v2\/media?parent=1340"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.wittwer.fr\/whiler\/wp-json\/wp\/v2\/categories?post=1340"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.wittwer.fr\/whiler\/wp-json\/wp\/v2\/tags?post=1340"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}