NekoX/TMessagesProj/src/main/java/org/telegram/ui/Components/SlideChooseView.java

package org.telegram.ui.Components;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.DashPathEffect;
import android.graphics.Paint;
import android.os.Bundle;
import android.text.TextPaint;
import android.view.MotionEvent;
import android.view.View;
import android.view.accessibility.AccessibilityNodeInfo;

import org.telegram.messenger.AndroidUtilities;
import org.telegram.ui.ActionBar.Theme;

public class SlideChooseView extends View {

    private final SeekBarAccessibilityDelegate accessibilityDelegate;

    private Paint paint;
    private Paint linePaint;
    private TextPaint textPaint;
    private int lastDash;

    private int circleSize;
    private int gapSize;
    private int sideSide;
    private int lineSize;

    private int dashedFrom = -1;

    private boolean moving;
    private boolean startMoving;
    private float startX;

    private int startMovingPreset;

    private String[] optionsStr;
    private int[] optionsSizes;

    private int selectedIndex;

    private Callback callback;

    public SlideChooseView(Context context) {
        super(context);

        paint = new Paint(Paint.ANTI_ALIAS_FLAG);
        textPaint = new TextPaint(Paint.ANTI_ALIAS_FLAG);
        linePaint = new Paint(Paint.ANTI_ALIAS_FLAG);
        linePaint.setStrokeWidth(AndroidUtilities.dp(2));
        linePaint.setStrokeCap(Paint.Cap.ROUND);
        textPaint.setTextSize(AndroidUtilities.dp(13));

        accessibilityDelegate = new IntSeekBarAccessibilityDelegate() {
            @Override
            protected int getProgress() {
                return selectedIndex;
            }

            @Override
            protected void setProgress(int progress) {
                setOption(progress);
            }

            @Override
            protected int getMaxValue() {
                return optionsStr.length - 1;
            }

            @Override
            protected CharSequence getContentDescription(View host) {
                return selectedIndex < optionsStr.length ? optionsStr[selectedIndex] : null;
            }
        };
    }

    public void setCallback(Callback callback) {
        this.callback = callback;
    }

    public void setOptions(int selected, String... options) {
        this.optionsStr = options;
        selectedIndex = selected;
        optionsSizes = new int[optionsStr.length];
        for (int i = 0; i < optionsStr.length; i++) {
            optionsSizes[i] = (int) Math.ceil(textPaint.measureText(optionsStr[i]));
        }
        requestLayout();
    }

    public void setDashedFrom(int from) {
        dashedFrom = from;
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        float x = event.getX();
        if (event.getAction() == MotionEvent.ACTION_DOWN) {
            getParent().requestDisallowInterceptTouchEvent(true);
            for (int a = 0; a < optionsStr.length; a++) {
                int cx = sideSide + (lineSize + gapSize * 2 + circleSize) * a + circleSize / 2;
                if (x > cx - AndroidUtilities.dp(15) && x < cx + AndroidUtilities.dp(15)) {
                    startMoving = a == selectedIndex;
                    startX = x;
                    startMovingPreset = selectedIndex;
                    break;
                }
            }
        } else if (event.getAction() == MotionEvent.ACTION_MOVE) {
            if (startMoving) {
                if (Math.abs(startX - x) >= AndroidUtilities.getPixelsInCM(0.5f, true)) {
                    moving = true;
                    startMoving = false;
                }
            } else if (moving) {
                for (int a = 0; a < optionsStr.length; a++) {
                    int cx = sideSide + (lineSize + gapSize * 2 + circleSize) * a + circleSize / 2;
                    int diff = lineSize / 2 + circleSize / 2 + gapSize;
                    if (x > cx - diff && x < cx + diff) {
                        if (selectedIndex != a) {
                            setOption(a);
                        }
                        break;
                    }
                }
            }
        } else if (event.getAction() == MotionEvent.ACTION_UP || event.getAction() == MotionEvent.ACTION_CANCEL) {
            if (!moving) {
                for (int a = 0; a < 5; a++) {
                    int cx = sideSide + (lineSize + gapSize * 2 + circleSize) * a + circleSize / 2;
                    if (x > cx - AndroidUtilities.dp(15) && x < cx + AndroidUtilities.dp(15)) {
                        if (selectedIndex != a) {
                            setOption(a);
                        }
                        break;
                    }
                }
            } else {
                if (selectedIndex != startMovingPreset) {
                    setOption(selectedIndex);
                }
            }
            if (callback != null) {
                callback.onTouchEnd();
            }
            startMoving = false;
            moving = false;
        }
        return true;
    }

    private void setOption(int index) {
        selectedIndex = index;
        if (callback != null) {
            callback.onOptionSelected(index);
        }
        invalidate();
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, MeasureSpec.makeMeasureSpec(AndroidUtilities.dp(74), MeasureSpec.EXACTLY));
        int width = MeasureSpec.getSize(widthMeasureSpec);
        circleSize = AndroidUtilities.dp(6);
        gapSize = AndroidUtilities.dp(2);
        sideSide = AndroidUtilities.dp(22);
        lineSize = (getMeasuredWidth() - circleSize * optionsStr.length - gapSize * 2 * (optionsStr.length - 1) - sideSide * 2) / (optionsStr.length - 1);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        textPaint.setColor(Theme.getColor(Theme.key_windowBackgroundWhiteGrayText));
        int cy = getMeasuredHeight() / 2 + AndroidUtilities.dp(11);

        for (int a = 0; a < optionsStr.length; a++) {
            int cx = sideSide + (lineSize + gapSize * 2 + circleSize) * a + circleSize / 2;
            if (a <= selectedIndex) {
                int color = Theme.getColor(Theme.key_switchTrackChecked);
                paint.setColor(color);
                linePaint.setColor(color);
            } else {
                int color = Theme.getColor(Theme.key_switchTrack);
                paint.setColor(color);
                linePaint.setColor(color);
            }
            canvas.drawCircle(cx, cy, a == selectedIndex ? AndroidUtilities.dp(6) : circleSize / 2, paint);
            if (a != 0) {
                int x = cx - circleSize / 2 - gapSize - lineSize;
                int width = lineSize;
                if (dashedFrom != -1 && a - 1 >= dashedFrom) {
                    x += AndroidUtilities.dp(3);
                    width -= AndroidUtilities.dp(3);
                    int dash = width / AndroidUtilities.dp(13);
                    if (lastDash != dash) {
                        float gap = (width - dash * AndroidUtilities.dp(8)) / (float) (dash - 1);
                        linePaint.setPathEffect(new DashPathEffect(new float[]{AndroidUtilities.dp(6), gap}, 0));
                        lastDash = dash;
                    }
                    canvas.drawLine(x + AndroidUtilities.dp(1), cy, x + width - AndroidUtilities.dp(1), cy, linePaint);
                } else {
                    if (a == selectedIndex || a == selectedIndex + 1) {
                        width -= AndroidUtilities.dp(3);
                    }
                    if (a == selectedIndex + 1) {
                        x += AndroidUtilities.dp(3);
                    }
                    canvas.drawRect(x, cy - AndroidUtilities.dp(1), x + width, cy + AndroidUtilities.dp(1), paint);
                }
            }
            int size = optionsSizes[a];
            String text = optionsStr[a];

            if (a == 0) {
                canvas.drawText(text, AndroidUtilities.dp(22), AndroidUtilities.dp(28), textPaint);
            } else if (a == optionsStr.length - 1) {
                canvas.drawText(text, getMeasuredWidth() - size - AndroidUtilities.dp(22), AndroidUtilities.dp(28), textPaint);
            } else {
                canvas.drawText(text, cx - size / 2, AndroidUtilities.dp(28), textPaint);
            }
        }
    }

    @Override
    public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {
        super.onInitializeAccessibilityNodeInfo(info);
        accessibilityDelegate.onInitializeAccessibilityNodeInfoInternal(this, info);
    }

    @Override
    public boolean performAccessibilityAction(int action, Bundle arguments) {
        return super.performAccessibilityAction(action, arguments) || accessibilityDelegate.performAccessibilityActionInternal(this, action, arguments);
    }

    public int getSelectedIndex() {
        return selectedIndex;
    }

    public interface Callback {
        void onOptionSelected(int index);

        default void onTouchEnd() {

        }
    }
}