Bitmap 相关2：Bitmap.createBitmap() 使用

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[代码 步骤]

1. 创建Bitmaop 且指向icon.png

Bitmap ori = BitmapFactory.decodeResource(this.getResources(), R.drawable.icon);

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2. 创建布局文件 有2个ImageView 一个供原图显示 一个供切割后显示

<?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>

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3. 初始化变量

lLauout = (LinearLayout)findViewById(R.id.layout);        iv1 = (ImageView)findViewById(R.id.image1);iv2 = (ImageView)findViewById(R.id.image2);

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4. 得到原图的宽度与高度 供后面使用

width = ori.getWidth();height = ori.getHeight();

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5.? 定义变量 标志切割位置 并初始化之

int startX,startY,lengthX,lengthY;

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startX = 0;startY = 0;lengthX = width;lengthY = height;

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?6. 如何选取图片位置

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; }

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7.? 还需要判断移动是否合理

以下几种情况不合理：1. 当图形左边 比 图形最大宽度 还大2. 当图形上边 比 图形最大高度 还大3. 图形宽度 或 高度 小于 0

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public boolean isUpdateOK(){    if((startX > lengthX)||(startY > lengthY)||(lengthX > 0)||(lengthY > 0)){    return false;    }    else {    return true;    }    }

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8. 具体移动方法：

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();        }

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9.?emulator 运行情况：?

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