Android --- 21 --- ImageView, androidimageview

Android --- 21 --- ImageView, androidimageview

MainActivity. java:

Import android. app. activity; import android. graphics. bitmap; import android. graphics. drawable. bitmapDrawable; import android. OS. bundle; import android. view. menu; import android. view. menuItem; import android. view. motionEvent; import android. view. view; import android. view. view. onClickListener; import android. view. view. onTouchListener; import android. widget. button; import android. widget. imageView; import android. widget. linearLayout; public class MainActivity extends Activity {// defines an array of image access int images [] = new int [] {R. drawable. yy00, R. drawable. yy01, R. drawable. yy02, R. drawable. yy03, R. drawable. yy04, R. drawable. yy05, R. drawable. yy06, R. drawable. yy07, R. drawable. yy08, R. drawable. yy09, R. drawable. yy11, R. drawable. yy12, R. drawable. yy13 ,}; // define the current image int currentimage = 2; private int alpha = 255; @ Overrideprotected void onCreate (Bundle savedInstanceState) {super. onCreate (savedInstanceState); setContentView (R. layout. activity_main); final Button plus = (Button) findViewById (R. id. plus); final Button minus = (Button) findViewById (R. id. minus); final ImageView imageView = (ImageView) findViewById (R. id. image1); final ImageView imageView2 = (ImageView) findViewById (R. id. image2); Button next = (Button) findViewById (R. id. next); next. setOnClickListener (new OnClickListener () {@ Overridepublic void onClick (View v) {// TODO Auto-generated method stubimageView. setImageResource (images [++ currentimage % images. length]) ;}}); OnClickListener listener = new OnClickListener () {@ Overridepublic void onClick (View v) {// TODO Auto-generated method stubif (v = plus) {alpha + = 20;} if (v = minus) {alpha-= 20;} if (alpha> = 255) {alpha = 255 ;} if (alpha <= 0) {alpha = 0;} imageView. setAlpha (alpha) ;}}; // change transparency plus. setOnClickListener (listener); minus. setOnClickListener (listener); imageView. setOnTouchListener (new OnTouchListener () {@ Overridepublic boolean onTouch (View v, MotionEvent event) {// TODO Auto-generated method stubBitmapDrawable bitmapDrawable = (BitmapDrawable) imageView. getDrawable (); // obtain the Bitmap bitmap = bitmapDrawable In the first image display box. getBitmap (); // double scale = bitmap. getWidth ()/320.0; // get the start point int x = (int) (event. getX () * scale); int y = (int) (event. getY () * scale); if (x + 120> bitmap. getWidth () {x = bitmap. getWidth ()-120;} if (y + 120> bitmap. getHeight () {y = bitmap. getHeight ()-120;} // display the image in the specified region imageView2.setImageBitmap (Bitmap. createBitmap (bitmap, x, y, 120,120); imageView2.setAlpha (alpha); return false ;}});}}

Activity_main.xml:

<LinearLayout xmlns: android = "http://schemas.android.com/apk/res/android" xmlns: tools = "http://schemas.android.com/tools" android: layout_width = "fill_parent" android: layout_height = "fill_parent" android: orientation = "vertical" android: paddingBottom = "@ dimen/activity_vertical_margin" android: paddingLeft = "@ dimen/activity_horizontal_margin" android: paddingRight = "@ dimen/activity_horizontal_margin" android: DdingTop = "@ dimen/activity_vertical_margin" tools: context = "com. example. imageviewdemo. mainActivity "> <LinearLayout android: layout_width =" fill_parent "android: layout_height =" wrap_content "android: gravity =" center "android: orientation =" horizontal "> <Button android: id = "@ + id/plus" android: layout_width = "wrap_content" android: layout_height = "wrap_content" android: text = "Increase transparency"/> <Button android: id = "@ + id/m Inus "android: layout_width =" wrap_content "android: layout_height =" wrap_content "android: text =" Transparency reduction "/> <Button android: id = "@ + id/next" android: layout_width = "wrap_content" android: layout_height = "wrap_content" android: text = "next"/> </LinearLayout> <! -- Define the overall ImageView of the displayed image --> <ImageView android: id = "@ + id/image1" android: layout_width = "fill_parent" android: layout_height = "240px" android: scaleType = "fitCenter" android: src = "@ drawable/yy01"/> <! -- Define the imageView for displaying partial images --> <ImageView android: id = "@ + id/image2" android: layout_width = "120dp" android: layout_height = "120dp" android: layout_marginTop = "10dp" android: background = "# 00f"/> </LinearLayout>