[Android] ScalableImageView

/*
 * Stan 2013/04/25
 * ver 2.0.8
 */
package com.stan.libs.imageview.scalable;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Matrix;
import android.graphics.PointF;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.view.View;
import android.widget.ImageView;

/*
 * @author: Stan
 */
public class StanScalableImageView extends ImageView {

private Matrix matrix = new Matrix();

// mode can be in one of these 3 states
private static final int NONE = 0;
private static final int DRAG = 1;
private static final int ZOOM = 2;
private int mode = NONE;

private static final int CLICK = 3;

// Remember some things
private PointF last = new PointF();
private PointF start = new PointF();
private float minScale = 1f;// default
private float maxScale = 3f;// default
private float minScaleTemp;// measure
private float maxScaleTemp;// measure
private float[] m;
private float redundantXSpace, redundantYSpace;
private float width, height;
private float nowScale = 1f;
private float origWidth, origHeight, imageWidth, imageHeight,
redundantWidth, redundantHeight;
private boolean fit = false;

private ScaleGestureDetector mScaleDetector;

public StanScalableImageView(Context context) {
super(context);
initStanScalableImageView(context);
}

public StanScalableImageView(Context context, AttributeSet attrs) {
super(context, attrs);
initStanScalableImageView(context);
}

public StanScalableImageView(Context context, AttributeSet attrs,
int defStyle) {
super(context, attrs, defStyle);
initStanScalableImageView(context);
}

private void initStanScalableImageView(Context context) {
super.setScaleType(ScaleType.CENTER);
mScaleDetector = new ScaleGestureDetector(context, new ScaleListener());
matrix.setTranslate(1f, 1f);
m = new float[9];
setImageMatrix(matrix);
setScaleType(ScaleType.MATRIX);
setOnTouchListener(new DragListener());
}

@Override
public void setImageBitmap(Bitmap bitmap) {
super.setImageBitmap(bitmap);
imageWidth = bitmap.getWidth();
imageHeight = bitmap.getHeight();
}

@Override
public void setImageDrawable(Drawable drawable) {
super.setImageDrawable(drawable);
imageWidth = drawable.getIntrinsicWidth();
imageHeight = drawable.getIntrinsicHeight();
}

@Override
public void setImageResource(int resourceID) {
super.setImageResource(resourceID);
imageWidth = getResources().getDrawable(resourceID).getIntrinsicWidth();
imageHeight = getResources().getDrawable(resourceID)
.getIntrinsicHeight();
}

public void setMaxZoom(float x) {
this.maxScale = x;
}

public void setMinZoom(float x) {
this.minScale = x;
}

public void setFit(boolean fit) {
this.fit = fit;
}

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
width = MeasureSpec.getSize(widthMeasureSpec);
height = MeasureSpec.getSize(heightMeasureSpec);
float scale;
if (fit) {
float scaleX = (float) width / (float) imageWidth;
float scaleY = (float) height / (float) imageHeight;
scale = Math.min(scaleX, scaleY);
matrix.setScale(scale, scale);
} else {
scale = 1;
}
minScaleTemp = minScale * scale;
maxScaleTemp = maxScale * scale;

setImageMatrix(matrix);
nowScale = scale;

// Center the image
redundantHeight = (scale * (float) imageHeight);
redundantWidth = (scale * (float) imageWidth);
redundantYSpace = (float) height - (scale * (float) imageHeight);
redundantXSpace = (float) width - redundantWidth;
redundantYSpace /= (float) 2;
redundantXSpace /= (float) 2;

matrix.getValues(m);
float x = m[Matrix.MTRANS_X];
float y = m[Matrix.MTRANS_Y];
matrix.postTranslate(redundantXSpace - x, redundantYSpace - y);

origWidth = width - 2 * redundantXSpace;
origHeight = height - 2 * redundantYSpace;
setImageMatrix(matrix);
}

private class DragListener implements OnTouchListener {

@Override
public boolean onTouch(View v, MotionEvent event) {
mScaleDetector.onTouchEvent(event);
matrix.getValues(m);
float x = m[Matrix.MTRANS_X];
float y = m[Matrix.MTRANS_Y];
PointF curr = new PointF(event.getX(), event.getY());

switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
last.set(event.getX(), event.getY());
start.set(last);
if (nowScale * imageWidth > width * 1.05
|| nowScale * imageHeight > height * 1.05) {
mode = DRAG;
}
break;
case MotionEvent.ACTION_MOVE:
float deltaX = curr.x - last.x;
float deltaY = curr.y - last.y;
if (mode == DRAG) {
float scaleWidth = Math.round(imageWidth * nowScale);
float scaleHeight = Math.round(imageHeight * nowScale);
// x
if (scaleWidth < width) {
deltaX = redundantXSpace - x
- (imageWidth * nowScale - redundantWidth) / 2;
} else {
if (deltaX > 0 && x + deltaX > 0) {
deltaX = -x;
} else if (deltaX < 0
&& x + deltaX + scaleWidth < width) {
deltaX = width - x - scaleWidth;
}
}
// y
if (scaleHeight < height) {
deltaY = redundantYSpace - y
- (imageHeight * nowScale - redundantHeight)
/ 2;
} else {
if (deltaY > 0 && y + deltaY > 0) {
deltaY = -y;
} else if (deltaY < 0
&& y + deltaY + scaleHeight < height) {
deltaY = height - y - scaleHeight;
}
}
matrix.postTranslate(deltaX, deltaY);
last.set(curr.x, curr.y);
}
break;

case MotionEvent.ACTION_UP:
mode = NONE;
int xDiff = (int) Math.abs(curr.x - start.x);
int yDiff = (int) Math.abs(curr.y - start.y);
if (xDiff < CLICK && yDiff < CLICK)
performClick();
break;

case MotionEvent.ACTION_POINTER_UP:
mode = NONE;
break;
}
setImageMatrix(matrix);
invalidate();
return true;
}
}

private class ScaleListener extends
ScaleGestureDetector.SimpleOnScaleGestureListener {
@Override
public boolean onScaleBegin(ScaleGestureDetector detector) {
mode = ZOOM;
last.set(detector.getFocusX(), detector.getFocusY());
start.set(last);
return true;
}

@Override
public boolean onScale(ScaleGestureDetector detector) {
float mScaleFactor = detector.getScaleFactor();
float origScale = nowScale;
nowScale *= mScaleFactor;
if (nowScale > maxScaleTemp) {
nowScale = maxScaleTemp;
mScaleFactor = maxScaleTemp / origScale;
} else if (nowScale < minScaleTemp) {
nowScale = minScaleTemp;
mScaleFactor = minScaleTemp / origScale;
}
if (origWidth * nowScale <= width
|| origHeight * nowScale <= height) {
matrix.postScale(mScaleFactor, mScaleFactor, width / 2,
height / 2);
} else {
matrix.postScale(mScaleFactor, mScaleFactor,
detector.getFocusX(), detector.getFocusY());
}
matrix.getValues(m);
float x = m[Matrix.MTRANS_X];
float y = m[Matrix.MTRANS_Y];
float scaleWidth = Math.round(imageWidth * nowScale);
float scaleHeight = Math.round(imageHeight * nowScale);
if (nowScale < origScale) {
if (x > 0 && x + scaleWidth > width) {
matrix.postTranslate(-x, 0);
} else if (x < 0 && x + scaleWidth < width) {
matrix.postTranslate(width - x - scaleWidth, 0);
} else if (x > 0 && x + scaleWidth < width) {
matrix.postTranslate((width - scaleWidth) / 2 - x, 0);
}
if (y > 0 && y + scaleHeight > height) {
matrix.postTranslate(0, -y);
} else if (y < 0 && y + scaleHeight < height) {
matrix.postTranslate(0, height - y - scaleHeight);
} else if (y > 0 && y + scaleHeight < height) {
matrix.postTranslate(0, (height - scaleHeight) / 2 - y);
}
}

PointF curr = new PointF(detector.getFocusX(), detector.getFocusY());
float deltaX = curr.x - last.x;
float deltaY = curr.y - last.y;
last.set(curr.x, curr.y);
// x
if (scaleWidth < width) {
deltaX = redundantXSpace - x
- (imageWidth * nowScale - redundantWidth) / 2;
return true;
} else {
if (deltaX > 0 && x + deltaX > 0) {
deltaX = -x;
} else if (deltaX < 0 && x + deltaX + scaleWidth < width) {
deltaX = width - x - scaleWidth;
}
}
// y
if (scaleHeight < height) {
deltaY = redundantYSpace - y
- (imageHeight * nowScale - redundantHeight) / 2;
return true;
} else {
if (deltaY > 0 && y + deltaY > 0) {
deltaY = -y;
} else if (deltaY < 0 && y + deltaY + scaleHeight < height) {
deltaY = height - y - scaleHeight;
}
}
matrix.postTranslate(deltaX, deltaY);
return true;
}
}
}

[Android] Gallery Scroll One Image At A Time

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34

public class ScrollOneImageAtATimeGallery extends Gallery { public ScrollOneImageAtATimeGallery(Context context) { super(context); } public ScrollOneImageAtATimeGallery(Context context, AttributeSet attrs) { super(context, attrs); } public ScrollOneImageAtATimeGallery(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); } private boolean isScrollingLeft(MotionEvent e1, MotionEvent e2) { return e2.getX() > e1.getX(); } @Override public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) { int kEvent; if (isScrollingLeft(e1, e2)) { // Check if scrolling left kEvent = KeyEvent.KEYCODE_DPAD_LEFT; } else { // Otherwise scrolling right kEvent = KeyEvent.KEYCODE_DPAD_RIGHT; } onKeyDown(kEvent, null); return true; } }

[Android] unlimit auto marquee TextView

code:

package com.stan.libs.textview;

import android.content.Context;
import android.util.AttributeSet;
import android.widget.TextView;

public class AlwaysMarqueeTextView extends TextView {

 public AlwaysMarqueeTextView(Context context) {
 super(context);
 }

 public AlwaysMarqueeTextView(Context context, AttributeSet attrs) {
 super(context, attrs);
 }

 public AlwaysMarqueeTextView(Context context, AttributeSet attrs, int defStyle) {
 super(context, attrs, defStyle);
 }

 @Override
 public boolean isFocused() {
 return true;
 }
}

Call by xml and set attributes:

android:ellipsize="marquee"
android:marqueeRepeatLimit="marquee_forever"
android:singleLine="true"

[Android] single line TextView auto reszie text size to match area height

Sometimes we want use a single line text witch can just match the height of TextView.
In http://developer.android.com/guide/practices/screens_support.html#screen-independence told us use dimen to adjust text size in different screen size, but we cant really achieve our goal by this way.

Search by Google can find http://stackoverflow.com/questions/5033012/auto-scale-textview-text-to-fit-within-bounds, but this TextView is set to avoid text size out of display bound,
，so I modified the code to make it:

PS. Because it's base on  "for", for better performance.
 I suggest that you also use dimen to set the default value.

package com.stan.libs.textview;

import android.content.Context;
import android.text.Layout.Alignment;
import android.text.StaticLayout;
import android.text.TextPaint;
import android.util.AttributeSet;
import android.util.TypedValue;
import android.widget.TextView;

public class AutoResizeToFillHeightTextView extends TextView {

 // Minimum text size for this text view
 public static final float MAX_TEXT_SIZE = 999;
 public static final float MIN_TEXT_SIZE = 8;

 // Interface for resize notifications
 public interface OnTextResizeListener {
  public void onTextResize(TextView textView, float oldSize, float newSize);
 }

 // Registered resize listener
 private OnTextResizeListener mTextResizeListener;

 // Flag for text and/or size changes to force a resize
 private boolean mNeedsResize = false;

 // Text size that is set from code. This acts as a starting point for
 // resizing
 private float mTextSize;

 // Temporary upper bounds on the starting text size
 private float mMaxTextSize = MAX_TEXT_SIZE;

 // Lower bounds for text size
 private float mMinTextSize = MIN_TEXT_SIZE;

 // Text view line spacing multiplier
 private float mSpacingMult = 1.0f;

 // Text view additional line spacing
 private float mSpacingAdd = 0.0f;

 // Default constructor override
 public AutoResizeToFillHeightTextView(Context context) {
  this(context, null);
 }

 // Default constructor when inflating from XML file
 public AutoResizeToFillHeightTextView(Context context, AttributeSet attrs) {
  this(context, attrs, 0);
 }

 // Default constructor override
 public AutoResizeToFillHeightTextView(Context context, AttributeSet attrs,
   int defStyle) {
  super(context, attrs, defStyle);
  mTextSize = getTextSize();
 }

 /**
  * If the text view size changed, set the force resize flag to true
  */
 @Override
 protected void onSizeChanged(int w, int h, int oldw, int oldh) {
  if (w != oldw || h != oldh) {
   mNeedsResize = true;
  }
 }

 /**
  * Register listener to receive resize notifications
  * 
  * @param listener
  */
 public void setOnResizeListener(OnTextResizeListener listener) {
  mTextResizeListener = listener;
 }

 /**
  * Override the set text size to update our internal reference values
  */
 @Override
 public void setTextSize(float size) {
  super.setTextSize(size);
  mTextSize = getTextSize();
 }

 /**
  * Override the set text size to update our internal reference values
  */
 @Override
 public void setTextSize(int unit, float size) {
  super.setTextSize(unit, size);
  mTextSize = getTextSize();
 }

 /**
  * Override the set line spacing to update our internal reference values
  */
 @Override
 public void setLineSpacing(float add, float mult) {
  super.setLineSpacing(add, mult);
  mSpacingMult = mult;
  mSpacingAdd = add;
 }

 /**
  * Set the upper text size limit and invalidate the view
  * 
  * @param maxTextSize
  */
 public void setMaxTextSize(float maxTextSize) {
  mMaxTextSize = maxTextSize;
  requestLayout();
  invalidate();
 }

 /**
  * Return upper text size limit
  * 
  * @return
  */
 public float getMaxTextSize() {
  return mMaxTextSize;
 }

 /**
  * Set the lower text size limit and invalidate the view
  * 
  * @param minTextSize
  */
 public void setMinTextSize(float minTextSize) {
  mMinTextSize = minTextSize;
  requestLayout();
  invalidate();
 }

 /**
  * Return lower text size limit
  * 
  * @return
  */
 public float getMinTextSize() {
  return mMinTextSize;
 }

 /**
  * Reset the text to the original size
  */
 public void resetTextSize() {
  if (mTextSize > 0) {
   super.setTextSize(TypedValue.COMPLEX_UNIT_PX, mTextSize);
  }
 }

 /**
  * Resize text after measuring
  */
 @Override
 protected void onLayout(boolean changed, int left, int top, int right,
   int bottom) {
  if (changed || mNeedsResize) {
   int widthLimit = (right - left) - getCompoundPaddingLeft()
     - getCompoundPaddingRight();
   int heightLimit = (bottom - top) - getCompoundPaddingBottom()
     - getCompoundPaddingTop();
   resizeText(widthLimit, heightLimit);
  }
  super.onLayout(changed, left, top, right, bottom);
 }

 /**
  * Resize the text size with default width and height
  */
 public void resizeText() {
  int heightLimit = getHeight() - getPaddingBottom() - getPaddingTop();
  int widthLimit = getWidth() - getPaddingLeft() - getPaddingRight();
  resizeText(widthLimit, heightLimit);
 }

 /**
  * Resize the text size with specified width and height
  * 
  * @param width
  * @param height
  */
 public void resizeText(int width, int height) {
  CharSequence text = getText();
  // Do not resize if the view does not have dimensions or there is no
  // text
  if (text == null || text.length() == 0 || height <= 0 || width <= 0
    || mTextSize == 0) {
   return;
  }

  // Get the text view's paint object
  TextPaint textPaint = getPaint();

  // Store the current text size
  float oldTextSize = textPaint.getTextSize();
  // If there is a max text size set, use the lesser of that and the
  // default text size
  float targetTextSize = mMaxTextSize > 0 ? Math.min(mTextSize,
    mMaxTextSize) : mTextSize;

  // Get the required text height
  int textHeight = getTextHeight(text, textPaint, width, targetTextSize);

  // Until we either fit within our text view or we had reached our min
  // text size, incrementally try smaller sizes
  while (textHeight > height && targetTextSize > mMinTextSize) {
   targetTextSize = Math.max(targetTextSize - 2, mMinTextSize);
   textHeight = getTextHeight(text, textPaint, width, targetTextSize);
  }

  // Until we either fit within our text view or we had reached our max
  // text size, incrementally try bigger sizes
  while (textHeight < height && targetTextSize < mMaxTextSize) {
   targetTextSize = Math.min(targetTextSize + 2, mMaxTextSize);
   textHeight = getTextHeight(text, textPaint, width, targetTextSize);
  }

  // Some devices try to auto adjust line spacing, so force default line
  // spacing
  // and invalidate the layout as a side effect
  textPaint.setTextSize(targetTextSize);
  setLineSpacing(mSpacingAdd, mSpacingMult);

  // Notify the listener if registered
  if (mTextResizeListener != null) {
   mTextResizeListener.onTextResize(this, oldTextSize, targetTextSize);
  }

  // Reset force resize flag
  mNeedsResize = false;
 }

 // Set the text size of the text paint object and use a static layout to
 // render text off screen before measuring
 private int getTextHeight(CharSequence source, TextPaint paint, int width,
   float textSize) {
  // Update the text paint object
  paint.setTextSize(textSize);
  // Measure using a static layout
  StaticLayout layout = new StaticLayout(source, paint, width,
    Alignment.ALIGN_NORMAL, mSpacingMult, mSpacingAdd, true);
  return layout.getHeight();
 }
}