Java tutorial
/* * Copyright (C) 2015 Quinn Chen * * 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 com.dean.phonesafe.ui; import android.animation.Animator; import android.animation.AnimatorListenerAdapter; import android.animation.ValueAnimator; import android.animation.ValueAnimator.AnimatorUpdateListener; import android.content.Context; import android.content.res.TypedArray; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.graphics.Rect; import android.graphics.RectF; import android.os.Bundle; import android.os.Looper; import android.os.Parcelable; import android.support.v4.view.MotionEventCompat; import android.util.AttributeSet; import android.view.MotionEvent; import android.view.View; import android.view.ViewGroup; import android.view.animation.AccelerateDecelerateInterpolator; import com.dean.phonesafe.R; public class SlideSwitch extends View { public static final int SHAPE_RECT = 1; public static final int SHAPE_CIRCLE = 2; private static final int RIM_SIZE = 1; private static final int DEFAULT_COLOR_THEME = Color.parseColor("#ff00ee00"); // 3 attributes private int color_theme; private boolean isOpen; private int shape; // varials of drawing private Paint paint; private Rect backRect; private Rect frontRect; private RectF frontCircleRect; private RectF backCircleRect; private int alpha; private int max_left; private int min_left; private int frontRect_left; private int frontRect_left_begin = RIM_SIZE; private int eventStartX; private int eventLastX; private int diffX = 0; private boolean slideable = true; private SlideListener listener; public interface SlideListener { public void open(); public void close(); } public SlideSwitch(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); listener = null; paint = new Paint(); // paint.setAntiAlias(true); //?Xml? TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.slideswitch); color_theme = a.getColor(R.styleable.slideswitch_themeColor, DEFAULT_COLOR_THEME); isOpen = a.getBoolean(R.styleable.slideswitch_isOpen, false); shape = a.getInt(R.styleable.slideswitch_shape, SHAPE_RECT); a.recycle(); } public SlideSwitch(Context context, AttributeSet attrs) { this(context, attrs, 0); } public SlideSwitch(Context context) { this(context, null); } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); int width; int height; //? ViewGroup.LayoutParams layoutParams = getLayoutParams(); width = layoutParams.width; height = layoutParams.height; if (width == ViewGroup.LayoutParams.MATCH_PARENT || width == ViewGroup.LayoutParams.WRAP_CONTENT) width = measureDimension(280, widthMeasureSpec);//?? if (height == ViewGroup.LayoutParams.MATCH_PARENT || height == ViewGroup.LayoutParams.WRAP_CONTENT) height = measureDimension(140, heightMeasureSpec);//?? if (shape == SHAPE_CIRCLE) { if (width < height) width = height * 2; } setMeasuredDimension(width, height); initDrawingVal(); } public void initDrawingVal() { int width = getMeasuredWidth(); int height = getMeasuredHeight(); backCircleRect = new RectF(); frontCircleRect = new RectF(); frontRect = new Rect(); backRect = new Rect(0, 0, width, height); min_left = RIM_SIZE; if (shape == SHAPE_RECT) max_left = width / 2; else max_left = width - (height - 2 * RIM_SIZE) - RIM_SIZE; if (isOpen) { frontRect_left = max_left; alpha = 255; } else { frontRect_left = RIM_SIZE; alpha = 0; } frontRect_left_begin = frontRect_left; } public int measureDimension(int defaultSize, int measureSpec) { int result; int specMode = MeasureSpec.getMode(measureSpec); int specSize = MeasureSpec.getSize(measureSpec); if (specMode == MeasureSpec.EXACTLY) { result = specSize; } else { result = defaultSize; // UNSPECIFIED if (specMode == MeasureSpec.AT_MOST) { result = Math.min(result, specSize); } } return result; } @Override protected void onDraw(Canvas canvas) { if (shape == SHAPE_RECT) { paint.setColor(Color.GRAY); canvas.drawRect(backRect, paint); paint.setColor(color_theme); paint.setAlpha(alpha); canvas.drawRect(backRect, paint); frontRect.set(frontRect_left, RIM_SIZE, frontRect_left + getMeasuredWidth() / 2 - RIM_SIZE, getMeasuredHeight() - RIM_SIZE); paint.setColor(Color.WHITE); canvas.drawRect(frontRect, paint); } else { // draw circle int radius; radius = backRect.height() / 2 - RIM_SIZE; paint.setColor(Color.GRAY); backCircleRect.set(backRect); canvas.drawRoundRect(backCircleRect, radius, radius, paint); paint.setColor(color_theme); paint.setAlpha(alpha); canvas.drawRoundRect(backCircleRect, radius, radius, paint); frontRect.set(frontRect_left, RIM_SIZE, frontRect_left + backRect.height() - 2 * RIM_SIZE, backRect.height() - RIM_SIZE); frontCircleRect.set(frontRect); paint.setColor(Color.WHITE); canvas.drawRoundRect(frontCircleRect, radius, radius, paint); } //?? //? paint.setStrokeWidth(2); paint.setAlpha(alpha); paint.setStyle(Paint.Style.STROKE); float gap = backRect.width() - frontRect.width(); float left = frontRect.left - gap + frontRect.width() / 2; canvas.drawLine(left, backRect.height() / 4, left, backRect.height() / 4 * 3, paint); //?? paint.setAlpha(255 - alpha); left = frontRect.left + gap + frontRect.width() / 2; canvas.drawCircle(left, backRect.height() / 2, frontRect.width() / 5, paint); // paint.setStyle(Paint.Style.FILL); } @Override public boolean onTouchEvent(MotionEvent event) { if (slideable == false) return super.onTouchEvent(event); int action = MotionEventCompat.getActionMasked(event); switch (action) { case MotionEvent.ACTION_DOWN: eventStartX = (int) event.getRawX(); break; case MotionEvent.ACTION_MOVE: eventLastX = (int) event.getRawX(); diffX = eventLastX - eventStartX; int tempX = diffX + frontRect_left_begin; tempX = (tempX > max_left ? max_left : tempX); tempX = (tempX < min_left ? min_left : tempX); if (tempX >= min_left && tempX <= max_left) { frontRect_left = tempX; alpha = (int) (255 * (float) tempX / (float) max_left); invalidateView(); } break; case MotionEvent.ACTION_UP: int wholeX = (int) (event.getRawX() - eventStartX); frontRect_left_begin = frontRect_left; boolean toRight; toRight = (frontRect_left_begin > max_left / 2 ? true : false); if (Math.abs(wholeX) < 10) { toRight = !toRight; } moveToDest(toRight); break; default: break; } return true; } /** * draw again */ private void invalidateView() { if (Looper.getMainLooper() == Looper.myLooper()) { invalidate(); } else { postInvalidate(); } } public void setSlideListener(SlideListener listener) { this.listener = listener; } public void moveToDest(final boolean toRight) { ValueAnimator toDestAnim = ValueAnimator.ofInt(frontRect_left, toRight ? max_left : min_left); toDestAnim.setDuration(500); toDestAnim.setInterpolator(new AccelerateDecelerateInterpolator()); toDestAnim.start(); toDestAnim.addUpdateListener(new AnimatorUpdateListener() { @Override public void onAnimationUpdate(ValueAnimator animation) { frontRect_left = (Integer) animation.getAnimatedValue(); alpha = (int) (255 * (float) frontRect_left / (float) max_left); invalidateView(); } }); toDestAnim.addListener(new AnimatorListenerAdapter() { @Override public void onAnimationEnd(Animator animation) { if (toRight) { isOpen = true; if (listener != null) listener.open(); frontRect_left_begin = max_left; } else { isOpen = false; if (listener != null) listener.close(); frontRect_left_begin = min_left; } } }); } public void setState(boolean isOpen) { this.isOpen = isOpen; initDrawingVal(); invalidateView(); if (listener != null) if (isOpen == true) { listener.open(); } else { listener.close(); } } public boolean getState() { return this.isOpen; } public void setShapeType(int shapeType) { this.shape = shapeType; } public void setSlideable(boolean slideable) { this.slideable = slideable; } @Override protected void onRestoreInstanceState(Parcelable state) { if (state instanceof Bundle) { Bundle bundle = (Bundle) state; this.isOpen = bundle.getBoolean("isOpen"); state = bundle.getParcelable("instanceState"); } super.onRestoreInstanceState(state); } @Override protected Parcelable onSaveInstanceState() { Bundle bundle = new Bundle(); bundle.putParcelable("instanceState", super.onSaveInstanceState()); bundle.putBoolean("isOpen", this.isOpen); return bundle; } }