android 图片放大?皇д?2,android 圆形图片带拖拽效果，点击事件

因为项目需要，，要做一个圆形的头像。可以在屏幕拖拽的效果。找了很多资料。

写了类似的效果。但是写完就废弃，换界面了。很无奈。。先留下来。以后用

public class Module_CircleImageView extends ImageView {

private static final ScaleType SCALE_TYPE = ScaleType.CENTER_CROP;

private static final Bitmap.Config BITMAP_CONFIG = Bitmap.Config.ARGB_8888;

private static final int COLORDRAWABLE_DIMENSION = 1;

private static final int DEFAULT_BORDER_WIDTH = 0;

private static final int DEFAULT_BORDER_COLOR = Color.WHITE;

private final RectF mDrawableRect = new RectF();

private final RectF mBorderRect = new RectF();

private final Matrix mShaderMatrix = new Matrix();

private final Paint mBitmapPaint = new Paint();

private final Paint mBorderPaint = new Paint();

private int mBorderColor = DEFAULT_BORDER_COLOR;

private int mBorderWidth = DEFAULT_BORDER_WIDTH;

private Bitmap mBitmap;

private BitmapShader mBitmapShader;

private int mBitmapWidth;

private int mBitmapHeight;

private float mDrawableRadius;

private float mBorderRadius;

private boolean mReady;

private boolean mSetupPending;

private int lastX,lastY;//��ʼλ��

private int screenWidth,screenHeight;//��Ļ�߿�

private boolean isMove;//�Ƿ���Ҫ�ƶ�

private boolean isclick;//�Ƿ��ǵ���¼�

private OnclickListener listener;//�Լ�д�ļ����¼�

private Context context;

public Module_CircleImageView(Context context) {

super(context);

this.context = context;

init();

}

public Module_CircleImageView(Context context, AttributeSet attrs) {

this(context, attrs, 0);

this.context = context;

init();

}

public void init(){

DisplayMetrics dm = getResources().getDisplayMetrics();

screenWidth = dm.widthPixels;

screenHeight = dm.heightPixels - 50;

}

public Module_CircleImageView(Context context, AttributeSet attrs, int defStyle) {

super(context, attrs, defStyle);

super.setScaleType(SCALE_TYPE);

TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.CircleImageView, defStyle, 0);

mBorderWidth = a.getDimensionPixelSize(R.styleable.CircleImageView_border_width, DEFAULT_BORDER_WIDTH);

mBorderColor = a.getColor(R.styleable.CircleImageView_border_color, DEFAULT_BORDER_COLOR);

a.recycle();

mReady = true;

if (mSetupPending) {

setup();

mSetupPending = false;

}

}

@Override

public ScaleType getScaleType() {

return SCALE_TYPE;

}

@Override

public void setScaleType(ScaleType scaleType) {

if (scaleType != SCALE_TYPE) {

throw new IllegalArgumentException(String.format("ScaleType %s not supported.", scaleType));

}

}

@Override

protected void onDraw(Canvas canvas) {

if (getDrawable() == null) {

return;

}

canvas.drawCircle(getWidth() / 2, getHeight() / 2, mDrawableRadius, mBitmapPaint);

canvas.drawCircle(getWidth() / 2, getHeight() / 2, mBorderRadius, mBorderPaint);

}

@Override

protected void onSizeChanged(int w, int h, int oldw, int oldh) {

super.onSizeChanged(w, h, oldw, oldh);

setup();

}

public int getBorderColor() {

return mBorderColor;

}

public void setBorderColor(int borderColor) {

if (borderColor == mBorderColor) {

return;

}

mBorderColor = borderColor;

mBorderPaint.setColor(mBorderColor);

invalidate();

}

public int getBorderWidth() {

return mBorderWidth;

}

public void setBorderWidth(int borderWidth) {

if (borderWidth == mBorderWidth) {

return;

}

mBorderWidth = borderWidth;

setup();

}

@Override

public void setImageBitmap(Bitmap bm) {

super.setImageBitmap(bm);

mBitmap = bm;

setup();

}

@Override

public void setImageDrawable(Drawable drawable) {

super.setImageDrawable(drawable);

mBitmap = getBitmapFromDrawable(drawable);

setup();

}

//设置是否可移动

public void setMove(boolean isMove){

this.isMove = isMove;

}

//因为重写了ontouch方法。所有重定义了点击事件

public void setClickListener(OnclickListener listener){

this.listener = listener;

}

@Override

public boolean onTouchEvent(MotionEvent event) {

if(!isMove)

return false;

switch (event.getAction()) {

case MotionEvent.ACTION_DOWN:

if(listener!=null)

isclick = true;

lastX = (int) event.getRawX();

lastY = (int) event.getRawY();

break;

case MotionEvent.ACTION_UP:

int enddx = (int) event.getRawX() - lastX;

int enddy = (int) event.getRawY() - lastY;

if((Math.abs(enddx)<3||Math.abs(enddy)<3)&&isclick){

listener.onclick(this);

return true;

}

break;

case MotionEvent.ACTION_MOVE:

int dx = (int) event.getRawX() - lastX;

int dy = (int) event.getRawY() - lastY;

int left = getLeft() + dx;

int top = getTop() + dy;

int right = getRight() + dx;

int bottom = getBottom() + dy;

if(Math.abs(dx)>3||Math.abs(dy)>3){

isclick=false;

}

// ���ò��ܳ���

if (left < 0) {

left = 0;

right = left + getWidth();

}

if (right > screenWidth) {

right = screenWidth;

left = right - getWidth();

}

if (top < 0) {

top = 0;

bottom = top + getHeight();

}

if (bottom > screenHeight-dip2px(this.getContext(),102)) {

bottom = screenHeight-dip2px(this.getContext(),102);

top = bottom - getHeight();

}

layout(left, top, right, bottom);

lastX = (int) event.getRawX();

lastY = (int) event.getRawY();

break;

}

return true;

}

/**

* 根据手机的分辨率从 dp 的单位 转成为 px(像素)

*/

public static int dip2px(Context context, float dpValue) {

final float scale = context.getResources().getDisplayMetrics().density;

return (int) (dpValue * scale + 0.5f);

}

@Override

public void setImageResource(int resId) {

super.setImageResource(resId);

mBitmap = getBitmapFromDrawable(getDrawable());

setup();

}

private Bitmap getBitmapFromDrawable(Drawable drawable) {

if (drawable == null) {

return null;

}

if (drawable instanceof BitmapDrawable) {

return ((BitmapDrawable) drawable).getBitmap();

}

try {

Bitmap bitmap;

if (drawable instanceof ColorDrawable) {

bitmap = Bitmap.createBitmap(COLORDRAWABLE_DIMENSION, COLORDRAWABLE_DIMENSION, BITMAP_CONFIG);

} else {

bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), BITMAP_CONFIG);

}

Canvas canvas = new Canvas(bitmap);

drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());

drawable.draw(canvas);

return bitmap;

} catch (OutOfMemoryError e) {

return null;

}

}

private void setup() {

if (!mReady) {

mSetupPending = true;

return;

}

if (mBitmap == null) {

return;

}

mBitmapShader = new BitmapShader(mBitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);

mBitmapPaint.setAntiAlias(true);

mBitmapPaint.setShader(mBitmapShader);

mBorderPaint.setStyle(Paint.Style.STROKE);

mBorderPaint.setAntiAlias(true);

mBorderPaint.setColor(mBorderColor);

mBorderPaint.setStrokeWidth(mBorderWidth);

mBitmapHeight = mBitmap.getHeight();

mBitmapWidth = mBitmap.getWidth();

mBorderRect.set(0, 0, getWidth(), getHeight());

mBorderRadius = Math.min((mBorderRect.height() - mBorderWidth) / 2, (mBorderRect.width() - mBorderWidth) / 2);

mDrawableRect.set(mBorderWidth, mBorderWidth, mBorderRect.width() - mBorderWidth, mBorderRect.height() - mBorderWidth);

mDrawableRadius = Math.min(mDrawableRect.height() / 2, mDrawableRect.width() / 2);

updateShaderMatrix();

invalidate();

}

private void updateShaderMatrix() {

float scale;

float dx = 0;

float dy = 0;

mShaderMatrix.set(null);

if (mBitmapWidth * mDrawableRect.height() > mDrawableRect.width() * mBitmapHeight) {

scale = mDrawableRect.height() / (float) mBitmapHeight;

dx = (mDrawableRect.width() - mBitmapWidth * scale) * 0.5f;

} else {

scale = mDrawableRect.width() / (float) mBitmapWidth;

dy = (mDrawableRect.height() - mBitmapHeight * scale) * 0.5f;

}

mShaderMatrix.setScale(scale, scale);

mShaderMatrix.postTranslate((int) (dx + 0.5f) + mBorderWidth, (int) (dy + 0.5f) + mBorderWidth);

mBitmapShader.setLocalMatrix(mShaderMatrix);

}

//因为重写了ontouch方法。所有重定义了点击事件

public interface OnclickListener{

public void onclick(View v);

}

}

留着以后用。可能有很多冗余的地方。以后再改了。