/*
* Copyright (C) 2013 Peng fei Pan <sky@xiaopan.me>
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package me.xiaopan.sketch.feature;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.os.Build;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.View;
import android.view.animation.DecelerateInterpolator;
import android.widget.Scroller;
import me.xiaopan.sketch.SLog;
import me.xiaopan.sketch.SketchImageView;
/**
* 显示按下状态，按下后会在ImageView上显示一个黑色半透明的蒙层，松手后小时
*/
public class ShowPressedFunction extends SketchImageView.Function {
private static final int DEFAULT_PRESSED_STATUS_COLOR = 0x33000000;
protected String logName = "ShowPressedFunction";
private View view;
private ImageShapeFunction imageShapeFunction;
protected int touchX;
protected int touchY;
protected int pressedStatusColor = DEFAULT_PRESSED_STATUS_COLOR;
protected int rippleRadius;
protected boolean allowShowPressedStatus;
protected boolean animationRunning;
protected Paint pressedStatusPaint;
protected GestureDetector gestureDetector;
protected boolean showRect;
public ShowPressedFunction(View view, ImageShapeFunction imageShapeFunction) {
this.view = view;
this.imageShapeFunction = imageShapeFunction;
this.gestureDetector = new GestureDetector(view.getContext(), new PressedStatusManager());
}
@Override
public boolean onTouchEvent(MotionEvent event) {
if (view.isClickable()) {
gestureDetector.onTouchEvent(event);
switch (event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_CANCEL:
case MotionEvent.ACTION_OUTSIDE:
allowShowPressedStatus = false;
view.invalidate();
break;
}
}
return false;
}
@Override
public void onDraw(Canvas canvas) {
if (allowShowPressedStatus || animationRunning || showRect) {
boolean applyMaskClip = imageShapeFunction.getClipPath() != null;
if (applyMaskClip) {
canvas.save();
try {
canvas.clipPath(imageShapeFunction.getClipPath());
} catch (UnsupportedOperationException e) {
SLog.e(logName, "The current environment doesn't support clipPath has shut down automatically hardware acceleration");
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
view.setLayerType(View.LAYER_TYPE_SOFTWARE, null);
}
e.printStackTrace();
}
}
if (pressedStatusPaint == null) {
pressedStatusPaint = new Paint();
pressedStatusPaint.setColor(pressedStatusColor);
pressedStatusPaint.setAntiAlias(true);
}
if (allowShowPressedStatus || animationRunning) {
canvas.drawCircle(touchX, touchY, rippleRadius, pressedStatusPaint);
} else if (showRect) {
canvas.drawRect(view.getPaddingLeft(), view.getPaddingTop(), view.getWidth() - view.getPaddingRight(), view.getHeight() - view.getPaddingBottom(), pressedStatusPaint);
}
if (applyMaskClip) {
canvas.restore();
}
}
}
public void setPressedStatusColor(int pressedStatusColor) {
this.pressedStatusColor = pressedStatusColor;
if (pressedStatusPaint != null) {
pressedStatusPaint.setColor(pressedStatusColor);
}
}
private class PressedStatusManager extends GestureDetector.SimpleOnGestureListener implements Runnable {
private boolean showPress;
private Scroller scroller;
private Runnable cancelRunnable;
public PressedStatusManager() {
scroller = new Scroller(view.getContext());
}
@Override
public void run() {
animationRunning = scroller.computeScrollOffset();
if (animationRunning) {
rippleRadius = scroller.getCurrX();
view.post(this);
}
view.invalidate();
}
@Override
public boolean onDown(MotionEvent event) {
if (!scroller.isFinished()) {
scroller.forceFinished(true);
view.removeCallbacks(this);
animationRunning = false;
view.invalidate();
}
touchX = (int) event.getX();
touchY = (int) event.getY();
showPress = false;
return false;
}
@Override
public void onShowPress(MotionEvent e) {
allowShowPressedStatus = true;
showPress = true;
startAnimation(1000);
}
@Override
public void onLongPress(MotionEvent e) {
super.onLongPress(e);
}
@Override
public boolean onSingleTapUp(MotionEvent e) {
if (!showPress) {
showRect = true;
view.invalidate();
if (cancelRunnable == null) {
cancelRunnable = new Runnable() {
@Override
public void run() {
showRect = false;
view.invalidate();
}
};
}
view.postDelayed(cancelRunnable, 200);
}
return super.onSingleTapUp(e);
}
private void startAnimation(int duration) {
if (scroller == null) {
scroller = new Scroller(view.getContext(), new DecelerateInterpolator());
}
scroller.startScroll(0, 0, computeRippleRadius(), 0, duration);
view.post(this);
}
/**
* 计算涟漪的半径
*
* @return 涟漪的半径
*/
private int computeRippleRadius() {
// 先计算按下点到四边的距离
int toLeftDistance = touchX - view.getPaddingLeft();
int toTopDistance = touchY - view.getPaddingTop();
int toRightDistance = Math.abs(view.getWidth() - view.getPaddingRight() - touchX);
int toBottomDistance = Math.abs(view.getHeight() - view.getPaddingBottom() - touchY);
// 当按下位置在第一或第四象限的时候，比较按下位置在左上角到右下角这条线上距离谁最远就以谁为半径，否则在左下角到右上角这条线上比较
int centerX = view.getWidth() / 2;
int centerY = view.getHeight() / 2;
if ((touchX < centerX && touchY < centerY) || (touchX > centerX && touchY > centerY)) {
int toLeftTopDistance = (int) Math.sqrt((toLeftDistance * toLeftDistance) + (toTopDistance * toTopDistance));
int toRightBottomDistance = (int) Math.sqrt((toRightDistance * toRightDistance) + (toBottomDistance * toBottomDistance));
return toLeftTopDistance > toRightBottomDistance ? toLeftTopDistance : toRightBottomDistance;
} else {
int toLeftBottomDistance = (int) Math.sqrt((toLeftDistance * toLeftDistance) + (toBottomDistance * toBottomDistance));
int toRightTopDistance = (int) Math.sqrt((toRightDistance * toRightDistance) + (toTopDistance * toTopDistance));
return toLeftBottomDistance > toRightTopDistance ? toLeftBottomDistance : toRightTopDistance;
}
}
}
}