Android implements bitmap clipping

We can't always rely on bitmapfactory to tell you how to intercept a part from BITMAQP to create a new bitmap
The system will have a default PNG image: Icon.png But the outermost part of the picture will be white. Now, for example, how to intercept because the outer layer is white, so I used *.9.png as its boundary.

Create BITMAOP and point to Icon.png

<span style= "FONT-SIZE:12PX;" >bitmap ori = Bitmapfactory.decoderesource (This.getresources (), R.drawable.icon);  </span>

Create a layout file There are 2 ImageView one for the original image display one for cutting after display

<?xml version= "1.0" encoding= "Utf-8"?> <linearlayout  xmlns:android= "http://schemas.android.com/apk/ Res/android "      android:orientation=" vertical "      android:layout_width=" fill_parent "      android:layout_ height= "Fill_parent"      android:id= "@+id/layout"      >  <imageview android:layout_width=        "Wrap_ Content "       android:layout_height=" wrap_content "       android:id=" @+id/image1 "      android:layout_gravity=" Center_horizontal "      />  <imageview        android:layout_width=" wrap_content "       android:layout_ height= "Wrap_content"       android:id= "@+id/image2"      android:layout_gravity= "center"      />  </ Linearlayout>  

Initialize Variables

Llauout = (linearlayout) Findviewbyid (r.id.layout);            Iv1 = (ImageView) Findviewbyid (r.id.image1);  Iv2 = (ImageView) Findviewbyid (r.id.image2);  

get the width and height of the original image for later use

<span style= "FONT-SIZE:12PX;" >width = Ori.getwidth ();  Height = ori.getheight ();  </span>

define a variable to mark the cut position and initialize it

<span style= "FONT-SIZE:12PX;" ><span class= "keyword" style= "Font-family:monaco, ' Dejavu Sans mono ', ' bitstream Vera Sans Mono ', Consolas, ' Courie R New ', monospace; line-height:18px; Color:rgb (127, 0, 85); Font-weight:bold; " >int</span><span style= "Font-family:monaco, ' Dejavu Sans mono ', ' bitstream Vera Sans Mono ', Consolas, ' Couri Er New ', monospace; line-height:18px; " > startx,starty,lengthx,lengthy; </span></span>

<span style= "Font-family:monaco, ' Dejavu Sans mono ', ' bitstream Vera Sans Mono ', Consolas, ' Courier New ', monospace; line-height:18px; " ></span>

<span style= "FONT-SIZE:12PX;" >startx = 0;  Starty = 0;    Lengthx = width;  lengthy = height;  </span>

How to choose a picture locationfunction Prototypes: Bitmap.createbitmap (Bitmap source, int x, int y, int width, int height)

Method 1: Adjust the parameters continuously: X,y,width,heighy
Method 2: Use the navigation key to control the above 4 variables respectively
Navigation key left: x
navigation key right: Width
on the navigation key: Y
under Navigation key: Height
bring it closer to the center of the picture and press the move fixed distance

public boolean OnKeyDown (Int. keycode, KeyEvent msg) {                    switch (keycode) {case          keyevent.keycode_dpad_left:              Updateleft ();              break;                        Case Keyevent.keycode_dpad_right:              updateright ();              break;          Case KEYEVENT.KEYCODE_DPAD_UP:              updateup ();              break;          Case Keyevent.keycode_dpad_down:              updatedown ();              break;          Case Keyevent.keycode_dpad_center:              showresult ();              break;          }                    return false;      }  

also need to determine whether the movement is reasonable

The following situations are unreasonable:
1. When the left side of the graph is larger than the maximum width
2. When the top of the graph is larger than the maximum height
3. Graphic width or height less than 0

public Boolean Isupdateok () {          if (StartX > lengthx) | | (Starty > lengthy) | | (Lengthx > 0) | | (lengthy > 0)) {              return false;          }          else {              return true;          }      }  

Specific Moving methods

public void Updateleft () {StartX + = step;          Lengthx = Width-startx;                    lengthy = Height-starty;                            if (Isupdateok ()) {target1.recycle ();                            Target1 = Bitmap.createbitmap (Ori,startx, Starty, Lengthx, lengthy);                            Iv2.setimagebitmap (TARGET1);          Setcontentview (llauout);          }} public void Updateup () {starty + = step;          Lengthx = Width-startx;                    lengthy = Height-starty;                            if (Isupdateok ()) {target1.recycle ();                            Target1 = Bitmap.createbitmap (Ori,startx, Starty, Lengthx, lengthy);                            Iv2.setimagebitmap (TARGET1);          Setcontentview (llauout);                    }} public void Updateright () {lengthx-= step;                            if (Isupdateok ()) {target1.recycle (); Target1 = Bitmap.createbiTMap (Ori,startx, Starty, Lengthx, lengthy);                            Iv2.setimagebitmap (TARGET1);          Setcontentview (llauout);                    }} public void Updatedown () {lengthy-= step;                            if (Isupdateok ()) {target1.recycle ();                            Target1 = Bitmap.createbitmap (Ori,startx, Starty, Lengthx, lengthy);                            Iv2.setimagebitmap (TARGET1);          Setcontentview (llauout);          }} public void Showresult () {Alertdialog.builder ab = new Alertdialog.builder (this);                    Alertdialog Adialog; Ab.setmessage ("StartX:" +startx+ "\ n" + "Starty:" +starty+ "\ n" + "LENGTHX:" +lengthx+ "\ n" + "lengthy:" +lengthy). Settitle          ("Show result"). Show ();;            Adialog = Ab.create ();                Adialog.show ();   }

Emulator operating conditions: